This document summarizes research on using paste fills technology for backfilling underground mines in Estonia's oil shale industry. The oil shale industry produces large amounts of waste rock that could be used for backfilling. Laboratory tests and theoretical investigations were conducted to determine the suitability of limestone and dolostone aggregates from Estonian oil shale mines as backfill materials. Analysis showed that limestone aggregates best meet the parameters for paste fills technology in Estonian conditions, including having a porosity of 40-50%, uniformity coefficient below 4, and flakiness index below 11%. The aggregates from Estonian oil shale mines are therefore suitable for use as backfill materials.
A review on utilization of mine waste on black cotton soileSAT Journals
Abstract Mine wastes are one of the chronic waste concerns. The volume of solid waste generated during mining process, is one of the main pollution concern. The presence of high concentration of heavy metals and acid producing mineral phases can endanger the environment if management of these wastes are not addressed properly. Mine wastes have numerous ecological effects viz Air, Land and Water. There is a great difficulty in finding space for the storage of wastes generated in enormous quantity. The review of past studies indicated that 50 to 60% of mine waste by volume can be used as coarse grained particle and 10 to 15% by volume as fine aggregate. Despite quite a lot of attempts to diminish the amount of waste, mine waste remains one of world’s largest waste streams. Black cotton soil on the other hand is problematic due to the presence of momtmorillonite that imparts high swell- shrink potentials. These soils are very hard when dry but loose strength completely when wet. Pavement surface on poor soil subgrade show early distress causing pavement failure. The present study examines the utilization of these wastes as stabilizers for black cotton soil for unpaved road construction. Keywords: Mine Waste, slag aggregate, Solid Waste Materials, Iron Ore slag
This document summarizes research on the potential use of mine water from abandoned oil shale mines in Estonia as a source of geothermal energy. Underground mining of oil shale over the past 90 years has created large underground voids that have filled with stable temperature water. The researchers created a 3D model of the mined areas and calculated the volume of mine water. Their analysis shows the mine water could be used for large heat pump stations to provide winter heating. The first pilot heat pump using mine water began operating in 2011. Using this renewable geothermal energy source could reduce heating costs.
perfomance and evaluation of limestone mine in gujratjyotiranavasiya
This project focuses on evaluating surface mining methods used in limestone mines in Gujarat, India. It illustrates the excavation methods and compares the merits and limitations of windrowing and direct loading. The document also discusses the geology of the limestone deposits, describes the machinery used including surface miners and loaders, and analyzes problems that can occur such as those related to weathering, reserves, and equipment damage.
Selective Comminution of Concrete Waste and Recovery of the Concrete Constitu...LOESCHE
Using a Loesche VRM, trials were carried out in order to determine the extent to which the constituents of concrete waste could be made suitable by a special recycling process for use as a substitute for the natural rock fraction in components. In this process, the employment of suitable separation equipment played a crucial role.
HEAVY EQUIPMENT EFFICIENCY, PRODUCTIVITY AND COMPATIBILITY OF COAL MINE OVERB...IAEME Publication
A mining activity starts with clearing the land from plants and overburden
stripping. The purpose of this study is to analyze the value of work efficiency,
productivity, and compatibility of heavy equipment in overburden work. This research
employs a descriptive method and includes a case study, then the data were obtained
from observations. The research results found that the value of workload efficiency is
74.63% and the value of conveyance is 58.37%; while the productivity of loading
equipment is 5,055 BCM/hour and conveyance is 5,189 BCM/hour; furthermore, the
match factor level of the equipment is 0.65. However, the match factor level is still
below the standard. Thus, further research is required to determine the appropriate
strategy to make the equipment's match factor level equal to one
use of stabilized block in housing projectSiddik Siddi
civil engineers would like it. its the ppt based on use of stabilized block in housing project,, used easy English..easy to understand and good toipic for easy guys
Strength characteristic of expansive soil admixed with flyash and limeNabam Budh
This document discusses a study on improving the strength and compressibility of expansive soil stabilized with fly ash and lime. The objectives were to determine basic soil properties, amounts of fly ash and lime for stabilization, and to increase strength and stability while reducing costs. Testing included compaction, unconfined compression, and consolidation tests on mixtures of expansive soil, fly ash, and lime. Results showed that adding fly ash decreased plasticity and increased dry density, while lime decreased dry density but increased optimum moisture content. Peak strength increased with fly ash and lime content up to optimal amounts of 10% fly ash and 3-5% lime. Consolidation testing was in progress. The study concluded that fly ash and lime improved soil properties
Ways of Utilization of Dust from Cement PlantsYogeshIJTSRD
The article discusses the properties of crushed stone lime asphalt concrete and the conditions for obtaining a high quality road surface during its application. The results of the study of replacing mineral powder in crushed stone asphalt concrete with dust, dust from cement plants and dust from pyrite slag, as well as a study of the stability of the quality of bitumen in time to normal and high temperatures are described. However, the selected areas of using cement plant dust cannot be considered particularly promising, since in the above methods, cement plant dust is easily replaced by chalk and limestone. In this regard, it is more promising to use dust from cement plants to obtain nitrogen calcium fertilizers, mainly containing calcium nitrate. Xidirova Yulduz Xo’janazarovna | Rosilov Mansur Sirgievich | Badalova N "Ways of Utilization of Dust from Cement Plants" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-3 , April 2021, URL: https://www.ijtsrd.com/papers/ijtsrd40001.pdf Paper URL: https://www.ijtsrd.com/engineering/chemical-engineering/40001/ways-of-utilization-of-dust-from-cement-plants/xidirova-yulduz-xo’janazarovna
A review on utilization of mine waste on black cotton soileSAT Journals
Abstract Mine wastes are one of the chronic waste concerns. The volume of solid waste generated during mining process, is one of the main pollution concern. The presence of high concentration of heavy metals and acid producing mineral phases can endanger the environment if management of these wastes are not addressed properly. Mine wastes have numerous ecological effects viz Air, Land and Water. There is a great difficulty in finding space for the storage of wastes generated in enormous quantity. The review of past studies indicated that 50 to 60% of mine waste by volume can be used as coarse grained particle and 10 to 15% by volume as fine aggregate. Despite quite a lot of attempts to diminish the amount of waste, mine waste remains one of world’s largest waste streams. Black cotton soil on the other hand is problematic due to the presence of momtmorillonite that imparts high swell- shrink potentials. These soils are very hard when dry but loose strength completely when wet. Pavement surface on poor soil subgrade show early distress causing pavement failure. The present study examines the utilization of these wastes as stabilizers for black cotton soil for unpaved road construction. Keywords: Mine Waste, slag aggregate, Solid Waste Materials, Iron Ore slag
This document summarizes research on the potential use of mine water from abandoned oil shale mines in Estonia as a source of geothermal energy. Underground mining of oil shale over the past 90 years has created large underground voids that have filled with stable temperature water. The researchers created a 3D model of the mined areas and calculated the volume of mine water. Their analysis shows the mine water could be used for large heat pump stations to provide winter heating. The first pilot heat pump using mine water began operating in 2011. Using this renewable geothermal energy source could reduce heating costs.
perfomance and evaluation of limestone mine in gujratjyotiranavasiya
This project focuses on evaluating surface mining methods used in limestone mines in Gujarat, India. It illustrates the excavation methods and compares the merits and limitations of windrowing and direct loading. The document also discusses the geology of the limestone deposits, describes the machinery used including surface miners and loaders, and analyzes problems that can occur such as those related to weathering, reserves, and equipment damage.
Selective Comminution of Concrete Waste and Recovery of the Concrete Constitu...LOESCHE
Using a Loesche VRM, trials were carried out in order to determine the extent to which the constituents of concrete waste could be made suitable by a special recycling process for use as a substitute for the natural rock fraction in components. In this process, the employment of suitable separation equipment played a crucial role.
HEAVY EQUIPMENT EFFICIENCY, PRODUCTIVITY AND COMPATIBILITY OF COAL MINE OVERB...IAEME Publication
A mining activity starts with clearing the land from plants and overburden
stripping. The purpose of this study is to analyze the value of work efficiency,
productivity, and compatibility of heavy equipment in overburden work. This research
employs a descriptive method and includes a case study, then the data were obtained
from observations. The research results found that the value of workload efficiency is
74.63% and the value of conveyance is 58.37%; while the productivity of loading
equipment is 5,055 BCM/hour and conveyance is 5,189 BCM/hour; furthermore, the
match factor level of the equipment is 0.65. However, the match factor level is still
below the standard. Thus, further research is required to determine the appropriate
strategy to make the equipment's match factor level equal to one
use of stabilized block in housing projectSiddik Siddi
civil engineers would like it. its the ppt based on use of stabilized block in housing project,, used easy English..easy to understand and good toipic for easy guys
Strength characteristic of expansive soil admixed with flyash and limeNabam Budh
This document discusses a study on improving the strength and compressibility of expansive soil stabilized with fly ash and lime. The objectives were to determine basic soil properties, amounts of fly ash and lime for stabilization, and to increase strength and stability while reducing costs. Testing included compaction, unconfined compression, and consolidation tests on mixtures of expansive soil, fly ash, and lime. Results showed that adding fly ash decreased plasticity and increased dry density, while lime decreased dry density but increased optimum moisture content. Peak strength increased with fly ash and lime content up to optimal amounts of 10% fly ash and 3-5% lime. Consolidation testing was in progress. The study concluded that fly ash and lime improved soil properties
Ways of Utilization of Dust from Cement PlantsYogeshIJTSRD
The article discusses the properties of crushed stone lime asphalt concrete and the conditions for obtaining a high quality road surface during its application. The results of the study of replacing mineral powder in crushed stone asphalt concrete with dust, dust from cement plants and dust from pyrite slag, as well as a study of the stability of the quality of bitumen in time to normal and high temperatures are described. However, the selected areas of using cement plant dust cannot be considered particularly promising, since in the above methods, cement plant dust is easily replaced by chalk and limestone. In this regard, it is more promising to use dust from cement plants to obtain nitrogen calcium fertilizers, mainly containing calcium nitrate. Xidirova Yulduz Xo’janazarovna | Rosilov Mansur Sirgievich | Badalova N "Ways of Utilization of Dust from Cement Plants" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-3 , April 2021, URL: https://www.ijtsrd.com/papers/ijtsrd40001.pdf Paper URL: https://www.ijtsrd.com/engineering/chemical-engineering/40001/ways-of-utilization-of-dust-from-cement-plants/xidirova-yulduz-xo’janazarovna
An Experimental Study on Stabilization Modification of Locally Available Expa...YogeshIJTSRD
Expansive soils are produced from the break down of basic igneous rocks where seasonal variation of weather is extreme. In India, these soils are normally derived from the weathering of basalt rocks. Also, these soil deposits are derived from various other types of rocks including very old sedimentary depositsin the present research, an attempt has been made to study the stabilization of the local soils high and low expansive having low bearing strength from two different parts of Bhopal by mixing independently with dolochar and fly ash plentily available in Bhopal in the proportions from 5 up to 30 by dry weight of the mixture with increment of 5 with and without lime The experimental programme conducted in this study is comprised of index tests, compaction tests, shear tests, unconfined compressive strength tests, CBR tests and consolidation tests in conformity with approved standards on soil alone and also on stabilised soils to evaluate their individual swelling, compaction, strength, compressibility and drainage characteristics. With addition of fly ash or dolochar, the L.L. and P.I. of soils gradually decreases with the increase of fly ash or dolochar contents. Maximum decrease is observed at 30 fly ash or 30 dolochar content Addition of fly ash or dolochar decreases the free swell index FSI of soil, maximum decrease being observed at fly ash or dolochar content of 30 . Addition of lime to the above mixtures, reduces FSI further. The FSI of soil 1 with 30 fly ash or dolochar content is reduced by 100 and 85 for soil fly ash and soil dolochar mixture respectively at 4 lime content. CBR of soil fly ash or soil dolochar increases with the increase of fly ash or dolochar content. The maximum increase being observed at 30 fly ash or dolochar content. At 30 fly ash content, the 4 days soaked CBR of soil 1 and soil 2 increase by 126 and 117 respectively, whereas, the 4 days soaked CBR of soil 1 and soil 2 at 30 dolochar content increase by 154 and 163 respectively. Sakshi Jaiswal | Prof. Nitesh Kushwah "An Experimental Study on Stabilization/Modification of Locally Available Expansive Soil using Industrial Wastes" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-5 , August 2021, URL: https://www.ijtsrd.com/papers/ijtsrd43834.pdf Paper URL: https://www.ijtsrd.com/engineering/civil-engineering/43834/an-experimental-study-on-stabilizationmodification-of-locally-available-expansive-soil-using-industrial-wastes/sakshi-jaiswal
The document describes an experimental study that aimed to stabilize expansive soil for sub-grade road construction using mixtures of marble dust, rice husk ash, and cement. Laboratory tests found that the soil samples had high plasticity indexes, free swell indexes, and low CBR values, indicating highly expansive soils. Stabilization was achieved by adding different proportions of the mixtures. CBR values increased as cement content increased, while plasticity decreased. Mixtures containing 8% rice husk ash or cement met Ethiopian road standards. The study demonstrated stabilized expansive soils can effectively be used for sub-grade construction when treated with the tested mixtures.
1. The document presents the results of an experimental study to stabilize expansive soils from Jimma, Ethiopia using mixtures of pumice and lime for subgrade road construction.
2. Laboratory tests found that the pumice contained high levels of silicon dioxide and aluminum oxide meeting standards for pozzolanic materials. Mixing lime and pumice reduced the plasticity index and increased the strength of expansive soils as measured by their California Bearing Ratio.
3. The optimum mix ratio found was 7% lime and 3% pumice, which decreased plasticity and increased the maximum dry density and bearing capacity of the soils making them suitable for use as subgrade material.
This document discusses different surface mining methods. It describes strip mining, terrace mining, and open-pit mining. Strip mining is used for relatively horizontal deposits with thin overburden. Terrace mining uses multiple benches when overburden is too thick for waste to be dumped in the pit. Open-pit mining is used for steeply dipping, pipe-shaped or irregular deposits where waste must be dumped outside the excavation area. Examples of each method are provided.
Mine planning process A Madowe SAIMM paperAlfred Madowe
This document provides background information on Letseng Diamonds (Pty) Ltd, an open-pit diamond mine located in Lesotho. It summarizes that Letseng mines two kimberlite pipes containing low-grade ore, employs conventional open-pit mining methods, and utilizes dense media separation and X-ray sorting in its processing plants. The mine planning process involves pit optimization and design using various software packages to determine the optimal pit design and schedule. Key inputs to the process include geological models, costs, diamond prices, and operational constraints.
IRJET- Study on Impact of Soil Stabilization using Lime, Brick Powder and Tam...IRJET Journal
This study evaluated the effectiveness of natural materials like tamarind kernel powder, lime, and brick powder for soil stabilization. Black cotton soil samples were mixed with varying proportions of these materials and their engineering properties were tested. Results showed that adding 35% brick powder and 5% lime improved the soil's properties the most, increasing maximum dry density and decreasing optimum moisture content. Tamarind kernel powder on its own also improved the soil when added at 2-8%, but a combination of 8% tamarind kernel powder and 10% lime worked better than tamarind kernel powder alone. The study concluded that lime, brick powder, and tamarind kernel powder can effectively stabilize soil in an eco-friendly manner.
Durability Studies on Concrete and Comparison with Partial Replacement of Cem...IJERA Editor
This research work describes the feasibility of using the Rice Husk Ash (RHA) and Sugarcane Bagasse Ash
(SCBA) waste in concrete production as a partial replacement of cement. This present work deals with the effect
on strength and mechanical properties of concrete using RHA and SCBA instead of cement. The cement has
been replaced by rice husk ash, accordingly in the range of 0%, 5%, 10%, 15%, and 20% by weight. Concrete
mixtures with RHA, were produced, tested and compared in terms of compressive strengths with the
Conventional concrete. These tests were carried out to evaluate the mechanical properties for the test results of
7, 28, 60, 90 days for compressive strengths in normal water and in MgSO4 solution of 1%, 3% and 5%. Also
the durability aspect for rice husk ash concrete for sulphate attack was tested. Similarly the above tests were also
performed for SCBA. The result indicates that the RHA and SCBA improve concrete durability. Finally the test
results for RHA and SCBA were compared. Key words: Rice Husk Ash, Sugarcane Bagasse Ash, Concrete,
M35 grade concrete, cubes, cylinders, MgSO4, durability.
IRJET- An Experimental Study on Stabilization of Black Cotton Soil by Using B...IRJET Journal
The document presents the results of an experimental study on stabilizing black cotton soil using burnt brick dust. Black cotton soil is problematic for construction due to its expansive properties when wet, resulting in poor soil strength and engineering properties. Laboratory tests were conducted on black cotton soil samples with the addition of 0%, 10%, 15%, and 20% burnt brick dust to evaluate their swelling potential, liquid limit, plastic limit, compaction characteristics, California Bearing Ratio (CBR), and unconfined compressive strength (UCS). The results showed that with the addition of burnt brick dust, the swelling potential, liquid limit, and plastic limit of the soil decreased while the maximum dry density increased and optimum moisture content decreased. CBR and
EVALUATING THE ENGINEERING PROPERTIES OF SANDY BRICKS MADE WITH DUNE SANDS, J...IAEME Publication
The document evaluates the engineering properties of sandy bricks made with dune sands in Jeddah, Saudi Arabia through an experimental study. Dune sands cover around 30% of Saudi Arabia and represent a potential local source of fine aggregates for construction. Physical and mechanical tests were conducted on dune sand samples and crushed fine aggregates. The results showed that dune sands met chemical stability requirements and could be used as up to 70% of fine aggregates in sand-cement bricks based on compressive strength tests. Using a mixture of dune sand and crushed aggregates improved the gradation properties over using dune sand alone.
An open pit mine is an excavation made at the surface of the ground to extract ore throughout the life of the mine. Large quantities of waste rock must be excavated and relocated to access and mine the ore deposit. The planning of an open pit mine aims to exploit the mineral deposit at the lowest cost while maximizing profits, through optimizing the physical design and scheduling of ore and waste extraction. Ore and waste materials are removed in successive layers called benches, with several benches potentially in operation simultaneously at different elevations in the open pit mine.
Environmental Factors Affecting Dimensional Stone QuarryingSushant Kumar
This document summarizes a study on the use of stone waste materials in construction. It finds that up to 30% replacement of natural aggregates with stone chips in concrete is economically viable and reduces waste. Stone waste can also be used to make floor finishes, bricks, tiles, and composites. The document also examines using vetiver grass to rehabilitate mine tailings and stabilize dump yard slopes, noting its strong root system and tolerance of various soil conditions.
IRJET- An Experimental Investigation on Concrete Manufactured by Partial Repl...IRJET Journal
This document discusses an experimental investigation into producing concrete by partially replacing m-sand (manufactured sand) with waste foundry sand and adding a polycarboxylate ether superplasticizer. Tests were conducted on standard cubes and cylinders to determine the mechanical properties of the concrete mixtures at 7, 14, and 28 days. The results showed that compressive and split tensile strength increased when replacing m-sand with 10-20% waste foundry sand but decreased with 25-30% replacement. Overall, the study aims to develop a more sustainable and low-cost concrete using an industrial waste material.
This document summarizes a research paper published in the International Journal of Advanced Research in Engineering and Technology. The paper studies the use of rice husk ash in cement mortar.
The document begins with background on the need for alternative binders to ordinary cement due to its high cost and environmental impact. It then discusses the potential of rice husk ash as a pozzolanic material and binder. The rest of the document reviews previous research conducted on using rice husk ash to produce cementitious materials and as a partial replacement for cement in concrete and mortar. Several methods for producing cement from rice husk ash are described, and their strengths and recommended applications provided. The document concludes by summarizing studies conducted on rice
M sand difference between river sand and m sand & Manufactured sand- properti...Denish Jangid
Manufactured sand (M-Sand) is produced by crushing granite stone in impact crushers. It is a substitute for river sand in concrete construction. M-Sand has cubical shapes with grounded edges and is washed and graded to less than 4.75mm. It is used as river sand deposits are being depleted and M-Sand addresses issues like availability, transportation costs, and quality variations in river sand. M-Sand improves the strength, durability, and workability of concrete while reducing construction defects and costs. It is a more sustainable alternative to river sand for concrete.
The document discusses a study that evaluated the performance of asphalt concrete mixes containing granular volcanic ash as a partial replacement for conventional aggregate. Four mix designs were tested with 0%, 10%, 20%, and 30% volcanic ash content by total aggregate weight. Testing showed that mixes with up to 20% volcanic ash met Marshall design specifications. Mixes with volcanic ash required slightly more asphalt but had comparable stability to the control mix. Additional testing found that mixes with 10% volcanic ash performed optimally in terms of resistance to stripping, creep, fatigue life, and resilience. The study aims to utilize volcanic ash waste in road construction and reduce related environmental and disposal impacts.
UTILIZATION OF SUGARCANE BAGASSE ASH AS A SUPPLEMENTARY CEMENTITIOUS MATERIAL...IAEME Publication
In developing countries, accumulation of unmanaged agricultural waste has resulted in an increased environmental concern. Recycling of such agricultural wastes is the viable solution not only to pollution problem, but also the problem of land filling. In view of utilization of agricultural waste in concrete and mortar, the present paper reviews, utilization of sugarcane bagasse ash (SCBA) in different compositions that were added to the raw material at different levels to develop
sustainable concrete and mortar. Various physico-mechanical properties of the concrete and mortar incorporating sugarcane bagasse ash are reviewed and recommendations are suggested as the outcome of the study.
Effect of sugarcane bagasse ash on strength properties of concreteeSAT Journals
Abstract The present study focuses on the utilization of Sugarcane Bagasse Ash as replacement material for cement in concrete production. Sugarcane Bagasse ash contains high amorphous silica content and aluminium ion. For experimental investigations, Sugarcane bagasse ash and its chemical properties are obtained from KCP sugar factory, Andhra Pradesh. Ordinary Portland cement was partly replaced by sugarcane bagasse ash in the ratio of 0%, 5%, 10%, 15%, 20% and 25% by weight and the influence of Sugarcane bagasse ash as a partial replacement material has been examined on fresh concrete tests by Compaction factor test and Slump cone test as well as on hardened concrete with tests for Compressive strength, Split tensile strength, Flexural strength and Modulus of Elasticity. The results indicate that inclusion of Sugarcane Bagasse Ash in concrete up to 20% level significantly enhanced the strength of concrete. The highest strength was obtained at 10% Sugarcane bagasse ash replacement level. Keywords: Sugarcane Bagasse Ash, By-Product, Amorphous Silica and Strength
Research on inter locking stabilised soil bricks (i.s.s.b.) a literature surveyeSAT Journals
Abstract This article present a literature study of research & development on Interlocking Stabilised Soil Bricks. The different developed
conceptional design for interlocking systems of blocks which is used for construction of brick walls described and various working
principles related to the Interlocking Stabilised Soil Bricks systems concepts are outlined. This is followed by & overviewed of
research work that has been related to I.S.S.B. by several research articles. The research work under taken which is received
categorised according to proposed I.S.S.B. systems concepts ( types of materials, of moulds, various compacting equipments,
economical consideration & others as per section 3 to 5 based on basis of this literature study, recommendation for future work.
Keywords: - Literature review, Interlocking Stabilised Soil Bricks, ISSB, Bricks, Soil, Laterite Soil, Sand
IRJET- Soil Stabilization by using Waste Material - Brick DustIRJET Journal
This document discusses using brick dust to stabilize black cotton soil for construction purposes. Black cotton soil is problematic for construction due to its high shrink-swell potential and low strength. The authors investigate using brick dust as an additive to improve the engineering properties of black cotton soil. They describe the properties of the untreated black cotton soil and brick dust. Laboratory tests are conducted to determine if brick dust improves the strength and reduces the volume change of black cotton soil. The results indicate whether brick dust is effective at stabilizing black cotton soil for construction applications.
This document is the ORCID profile page of Ingo Valgma, which contains information about his ORCID ID, other researcher IDs, education, employment, and works. It provides a centralized way to identify Ingo Valgma and link his research activities and outputs. The profile lists over 20 publications he has authored related to oil shale resources, mining, water quality and vegetation restoration in Estonia.
The document discusses Estonia's oil shale resources and how estimates of mineable reserves are calculated based on energy content. Currently, the minimum energy content used to define reserves is 35 GJ/m2. However, with new solid-heat carrier technology for producing oil, the cutoff grade could be lower, increasing mineable reserves. This technology can process raw run-of-mine shale whereas existing lump shale processing requires higher grade separated shale. Using the new technology and eliminating separation could lower production costs and increase capacity, making additional reserves economically viable. The authors use modeling to estimate how oil yields and potential reserves may increase under the new approach.
An Experimental Study on Stabilization Modification of Locally Available Expa...YogeshIJTSRD
Expansive soils are produced from the break down of basic igneous rocks where seasonal variation of weather is extreme. In India, these soils are normally derived from the weathering of basalt rocks. Also, these soil deposits are derived from various other types of rocks including very old sedimentary depositsin the present research, an attempt has been made to study the stabilization of the local soils high and low expansive having low bearing strength from two different parts of Bhopal by mixing independently with dolochar and fly ash plentily available in Bhopal in the proportions from 5 up to 30 by dry weight of the mixture with increment of 5 with and without lime The experimental programme conducted in this study is comprised of index tests, compaction tests, shear tests, unconfined compressive strength tests, CBR tests and consolidation tests in conformity with approved standards on soil alone and also on stabilised soils to evaluate their individual swelling, compaction, strength, compressibility and drainage characteristics. With addition of fly ash or dolochar, the L.L. and P.I. of soils gradually decreases with the increase of fly ash or dolochar contents. Maximum decrease is observed at 30 fly ash or 30 dolochar content Addition of fly ash or dolochar decreases the free swell index FSI of soil, maximum decrease being observed at fly ash or dolochar content of 30 . Addition of lime to the above mixtures, reduces FSI further. The FSI of soil 1 with 30 fly ash or dolochar content is reduced by 100 and 85 for soil fly ash and soil dolochar mixture respectively at 4 lime content. CBR of soil fly ash or soil dolochar increases with the increase of fly ash or dolochar content. The maximum increase being observed at 30 fly ash or dolochar content. At 30 fly ash content, the 4 days soaked CBR of soil 1 and soil 2 increase by 126 and 117 respectively, whereas, the 4 days soaked CBR of soil 1 and soil 2 at 30 dolochar content increase by 154 and 163 respectively. Sakshi Jaiswal | Prof. Nitesh Kushwah "An Experimental Study on Stabilization/Modification of Locally Available Expansive Soil using Industrial Wastes" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-5 , August 2021, URL: https://www.ijtsrd.com/papers/ijtsrd43834.pdf Paper URL: https://www.ijtsrd.com/engineering/civil-engineering/43834/an-experimental-study-on-stabilizationmodification-of-locally-available-expansive-soil-using-industrial-wastes/sakshi-jaiswal
The document describes an experimental study that aimed to stabilize expansive soil for sub-grade road construction using mixtures of marble dust, rice husk ash, and cement. Laboratory tests found that the soil samples had high plasticity indexes, free swell indexes, and low CBR values, indicating highly expansive soils. Stabilization was achieved by adding different proportions of the mixtures. CBR values increased as cement content increased, while plasticity decreased. Mixtures containing 8% rice husk ash or cement met Ethiopian road standards. The study demonstrated stabilized expansive soils can effectively be used for sub-grade construction when treated with the tested mixtures.
1. The document presents the results of an experimental study to stabilize expansive soils from Jimma, Ethiopia using mixtures of pumice and lime for subgrade road construction.
2. Laboratory tests found that the pumice contained high levels of silicon dioxide and aluminum oxide meeting standards for pozzolanic materials. Mixing lime and pumice reduced the plasticity index and increased the strength of expansive soils as measured by their California Bearing Ratio.
3. The optimum mix ratio found was 7% lime and 3% pumice, which decreased plasticity and increased the maximum dry density and bearing capacity of the soils making them suitable for use as subgrade material.
This document discusses different surface mining methods. It describes strip mining, terrace mining, and open-pit mining. Strip mining is used for relatively horizontal deposits with thin overburden. Terrace mining uses multiple benches when overburden is too thick for waste to be dumped in the pit. Open-pit mining is used for steeply dipping, pipe-shaped or irregular deposits where waste must be dumped outside the excavation area. Examples of each method are provided.
Mine planning process A Madowe SAIMM paperAlfred Madowe
This document provides background information on Letseng Diamonds (Pty) Ltd, an open-pit diamond mine located in Lesotho. It summarizes that Letseng mines two kimberlite pipes containing low-grade ore, employs conventional open-pit mining methods, and utilizes dense media separation and X-ray sorting in its processing plants. The mine planning process involves pit optimization and design using various software packages to determine the optimal pit design and schedule. Key inputs to the process include geological models, costs, diamond prices, and operational constraints.
IRJET- Study on Impact of Soil Stabilization using Lime, Brick Powder and Tam...IRJET Journal
This study evaluated the effectiveness of natural materials like tamarind kernel powder, lime, and brick powder for soil stabilization. Black cotton soil samples were mixed with varying proportions of these materials and their engineering properties were tested. Results showed that adding 35% brick powder and 5% lime improved the soil's properties the most, increasing maximum dry density and decreasing optimum moisture content. Tamarind kernel powder on its own also improved the soil when added at 2-8%, but a combination of 8% tamarind kernel powder and 10% lime worked better than tamarind kernel powder alone. The study concluded that lime, brick powder, and tamarind kernel powder can effectively stabilize soil in an eco-friendly manner.
Durability Studies on Concrete and Comparison with Partial Replacement of Cem...IJERA Editor
This research work describes the feasibility of using the Rice Husk Ash (RHA) and Sugarcane Bagasse Ash
(SCBA) waste in concrete production as a partial replacement of cement. This present work deals with the effect
on strength and mechanical properties of concrete using RHA and SCBA instead of cement. The cement has
been replaced by rice husk ash, accordingly in the range of 0%, 5%, 10%, 15%, and 20% by weight. Concrete
mixtures with RHA, were produced, tested and compared in terms of compressive strengths with the
Conventional concrete. These tests were carried out to evaluate the mechanical properties for the test results of
7, 28, 60, 90 days for compressive strengths in normal water and in MgSO4 solution of 1%, 3% and 5%. Also
the durability aspect for rice husk ash concrete for sulphate attack was tested. Similarly the above tests were also
performed for SCBA. The result indicates that the RHA and SCBA improve concrete durability. Finally the test
results for RHA and SCBA were compared. Key words: Rice Husk Ash, Sugarcane Bagasse Ash, Concrete,
M35 grade concrete, cubes, cylinders, MgSO4, durability.
IRJET- An Experimental Study on Stabilization of Black Cotton Soil by Using B...IRJET Journal
The document presents the results of an experimental study on stabilizing black cotton soil using burnt brick dust. Black cotton soil is problematic for construction due to its expansive properties when wet, resulting in poor soil strength and engineering properties. Laboratory tests were conducted on black cotton soil samples with the addition of 0%, 10%, 15%, and 20% burnt brick dust to evaluate their swelling potential, liquid limit, plastic limit, compaction characteristics, California Bearing Ratio (CBR), and unconfined compressive strength (UCS). The results showed that with the addition of burnt brick dust, the swelling potential, liquid limit, and plastic limit of the soil decreased while the maximum dry density increased and optimum moisture content decreased. CBR and
EVALUATING THE ENGINEERING PROPERTIES OF SANDY BRICKS MADE WITH DUNE SANDS, J...IAEME Publication
The document evaluates the engineering properties of sandy bricks made with dune sands in Jeddah, Saudi Arabia through an experimental study. Dune sands cover around 30% of Saudi Arabia and represent a potential local source of fine aggregates for construction. Physical and mechanical tests were conducted on dune sand samples and crushed fine aggregates. The results showed that dune sands met chemical stability requirements and could be used as up to 70% of fine aggregates in sand-cement bricks based on compressive strength tests. Using a mixture of dune sand and crushed aggregates improved the gradation properties over using dune sand alone.
An open pit mine is an excavation made at the surface of the ground to extract ore throughout the life of the mine. Large quantities of waste rock must be excavated and relocated to access and mine the ore deposit. The planning of an open pit mine aims to exploit the mineral deposit at the lowest cost while maximizing profits, through optimizing the physical design and scheduling of ore and waste extraction. Ore and waste materials are removed in successive layers called benches, with several benches potentially in operation simultaneously at different elevations in the open pit mine.
Environmental Factors Affecting Dimensional Stone QuarryingSushant Kumar
This document summarizes a study on the use of stone waste materials in construction. It finds that up to 30% replacement of natural aggregates with stone chips in concrete is economically viable and reduces waste. Stone waste can also be used to make floor finishes, bricks, tiles, and composites. The document also examines using vetiver grass to rehabilitate mine tailings and stabilize dump yard slopes, noting its strong root system and tolerance of various soil conditions.
IRJET- An Experimental Investigation on Concrete Manufactured by Partial Repl...IRJET Journal
This document discusses an experimental investigation into producing concrete by partially replacing m-sand (manufactured sand) with waste foundry sand and adding a polycarboxylate ether superplasticizer. Tests were conducted on standard cubes and cylinders to determine the mechanical properties of the concrete mixtures at 7, 14, and 28 days. The results showed that compressive and split tensile strength increased when replacing m-sand with 10-20% waste foundry sand but decreased with 25-30% replacement. Overall, the study aims to develop a more sustainable and low-cost concrete using an industrial waste material.
This document summarizes a research paper published in the International Journal of Advanced Research in Engineering and Technology. The paper studies the use of rice husk ash in cement mortar.
The document begins with background on the need for alternative binders to ordinary cement due to its high cost and environmental impact. It then discusses the potential of rice husk ash as a pozzolanic material and binder. The rest of the document reviews previous research conducted on using rice husk ash to produce cementitious materials and as a partial replacement for cement in concrete and mortar. Several methods for producing cement from rice husk ash are described, and their strengths and recommended applications provided. The document concludes by summarizing studies conducted on rice
M sand difference between river sand and m sand & Manufactured sand- properti...Denish Jangid
Manufactured sand (M-Sand) is produced by crushing granite stone in impact crushers. It is a substitute for river sand in concrete construction. M-Sand has cubical shapes with grounded edges and is washed and graded to less than 4.75mm. It is used as river sand deposits are being depleted and M-Sand addresses issues like availability, transportation costs, and quality variations in river sand. M-Sand improves the strength, durability, and workability of concrete while reducing construction defects and costs. It is a more sustainable alternative to river sand for concrete.
The document discusses a study that evaluated the performance of asphalt concrete mixes containing granular volcanic ash as a partial replacement for conventional aggregate. Four mix designs were tested with 0%, 10%, 20%, and 30% volcanic ash content by total aggregate weight. Testing showed that mixes with up to 20% volcanic ash met Marshall design specifications. Mixes with volcanic ash required slightly more asphalt but had comparable stability to the control mix. Additional testing found that mixes with 10% volcanic ash performed optimally in terms of resistance to stripping, creep, fatigue life, and resilience. The study aims to utilize volcanic ash waste in road construction and reduce related environmental and disposal impacts.
UTILIZATION OF SUGARCANE BAGASSE ASH AS A SUPPLEMENTARY CEMENTITIOUS MATERIAL...IAEME Publication
In developing countries, accumulation of unmanaged agricultural waste has resulted in an increased environmental concern. Recycling of such agricultural wastes is the viable solution not only to pollution problem, but also the problem of land filling. In view of utilization of agricultural waste in concrete and mortar, the present paper reviews, utilization of sugarcane bagasse ash (SCBA) in different compositions that were added to the raw material at different levels to develop
sustainable concrete and mortar. Various physico-mechanical properties of the concrete and mortar incorporating sugarcane bagasse ash are reviewed and recommendations are suggested as the outcome of the study.
Effect of sugarcane bagasse ash on strength properties of concreteeSAT Journals
Abstract The present study focuses on the utilization of Sugarcane Bagasse Ash as replacement material for cement in concrete production. Sugarcane Bagasse ash contains high amorphous silica content and aluminium ion. For experimental investigations, Sugarcane bagasse ash and its chemical properties are obtained from KCP sugar factory, Andhra Pradesh. Ordinary Portland cement was partly replaced by sugarcane bagasse ash in the ratio of 0%, 5%, 10%, 15%, 20% and 25% by weight and the influence of Sugarcane bagasse ash as a partial replacement material has been examined on fresh concrete tests by Compaction factor test and Slump cone test as well as on hardened concrete with tests for Compressive strength, Split tensile strength, Flexural strength and Modulus of Elasticity. The results indicate that inclusion of Sugarcane Bagasse Ash in concrete up to 20% level significantly enhanced the strength of concrete. The highest strength was obtained at 10% Sugarcane bagasse ash replacement level. Keywords: Sugarcane Bagasse Ash, By-Product, Amorphous Silica and Strength
Research on inter locking stabilised soil bricks (i.s.s.b.) a literature surveyeSAT Journals
Abstract This article present a literature study of research & development on Interlocking Stabilised Soil Bricks. The different developed
conceptional design for interlocking systems of blocks which is used for construction of brick walls described and various working
principles related to the Interlocking Stabilised Soil Bricks systems concepts are outlined. This is followed by & overviewed of
research work that has been related to I.S.S.B. by several research articles. The research work under taken which is received
categorised according to proposed I.S.S.B. systems concepts ( types of materials, of moulds, various compacting equipments,
economical consideration & others as per section 3 to 5 based on basis of this literature study, recommendation for future work.
Keywords: - Literature review, Interlocking Stabilised Soil Bricks, ISSB, Bricks, Soil, Laterite Soil, Sand
IRJET- Soil Stabilization by using Waste Material - Brick DustIRJET Journal
This document discusses using brick dust to stabilize black cotton soil for construction purposes. Black cotton soil is problematic for construction due to its high shrink-swell potential and low strength. The authors investigate using brick dust as an additive to improve the engineering properties of black cotton soil. They describe the properties of the untreated black cotton soil and brick dust. Laboratory tests are conducted to determine if brick dust improves the strength and reduces the volume change of black cotton soil. The results indicate whether brick dust is effective at stabilizing black cotton soil for construction applications.
This document is the ORCID profile page of Ingo Valgma, which contains information about his ORCID ID, other researcher IDs, education, employment, and works. It provides a centralized way to identify Ingo Valgma and link his research activities and outputs. The profile lists over 20 publications he has authored related to oil shale resources, mining, water quality and vegetation restoration in Estonia.
The document discusses Estonia's oil shale resources and how estimates of mineable reserves are calculated based on energy content. Currently, the minimum energy content used to define reserves is 35 GJ/m2. However, with new solid-heat carrier technology for producing oil, the cutoff grade could be lower, increasing mineable reserves. This technology can process raw run-of-mine shale whereas existing lump shale processing requires higher grade separated shale. Using the new technology and eliminating separation could lower production costs and increase capacity, making additional reserves economically viable. The authors use modeling to estimate how oil yields and potential reserves may increase under the new approach.
The document discusses oil shale mining-related research in Estonia. It notes that efficiency of oil shale usage depends mainly on mining technology. Current topics being investigated include backfilling mines, mechanical extraction of shale, and digital modeling of mining processes. The document advocates for further developing mechanical extraction methods like continuous miners to increase oil yield and productivity compared to current room and pillar mining techniques. Overall the research aims to identify best available technologies for sustainable and environmentally-friendly underground mining in Estonia.
The document discusses mining waste reduction methods through several pilot projects in different Baltic Sea Region countries. The Estonian project involves a mobile unit for processing mining waste into construction aggregates. The Swedish project develops a process for extracting valuable and hazardous metals from mining and metal waste. The Finnish project tests recycling mine waste by constructing a mobile module to grind and classify materials for potential use in wastewater purification. The Polish project produces artificial aggregate from mineral processing waste for construction using an agglomeration process. Overall the projects aim to promote sustainable waste management and resource recovery in the mining industry through knowledge sharing and demonstration of technologies across the Baltic Sea Region.
The document summarizes a study on the influence of water discharging from oil shale and limestone mining sites on water balance and quality in the Toolse River in Estonia from 2005-2009. Water is pumped from underground mines and quarries to keep the mining areas dry. This pumped water is directed to sedimentation ponds and then discharged into the Toolse River, increasing its flow. Water quality in the river was analyzed at various points and complied with standards except for higher total phosphorus levels downstream. The mining activities lower local groundwater levels and affect flows in the Toolse River and regional aquifers.
This document summarizes a study of mine blasts at the Aru-Lõuna Limestone Quarry in Estonia using seismology and mining engineering methods. Around 120 blasts are conducted at the quarry annually to produce limestone for cement production, but seismic monitoring stations only detect a few events. The study examined 12 seismic events registered between 2010-2012 that were located as resulting from blasts at the quarry. Factors like explosive type and amount, blast design, and local geology that could influence vibration intensity were investigated. While blast details did not consistently explain detected vs undetected events, improving data sharing between quarry operators and seismologists may help better understand local seismic activity from mining.
1. This document discusses applying risk assessment concepts in the Estonian mining industry. It notes that 80% of mining operations in Estonia are underground mines that present various safety and environmental risks.
2. The document recommends using risk assessment methods like failure mode and effect analysis to evaluate risks in mining operations. It also suggests establishing acceptable and tolerable risk criteria adapted to the Estonian context.
3. Specific risks addressed include roof and wall stability in underground mines, transportation accidents, and environmental impacts. The document concludes that introducing risk assessment practices could help improve safety and environmental protection in Estonian mines.
Valgma possibilities for mitigating negative effects of noise and dust caused...Ingo Valgma
This document summarizes research on mitigating the negative effects of noise and dust from extracting peat, sand, and gravel. Measurements of dust and noise were taken at extraction sites in Estonia. For peat extraction, dust levels were between 0.002-0.448 mg/m3 and noise levels averaged 58 dB at sites. Preserving surrounding forests at least 50 meters wide was found to effectively reduce dust and noise impacts. Modeling showed dust dispersed to only 300 meters from sites and noise decreased below limits within inhabited areas. Mitigation methods recommended preserving bordering forests and controlling vehicle speeds and loads to minimize dust.
This document summarizes research on reducing oil shale losses during mining operations in Estonia. It finds that oil shale utilization losses can reach up to 70% depending on the mine and methods used. The researchers analyzed various extraction, crushing, separation and processing methods used in Estonia's oil shale mines. These included selective blasting, longwall mining, surface mining, mechanical shovel extraction, and fine separation technologies. Test results showed that surface miners can achieve productivities over 500 tonnes per hour with cutting speeds around 0.05-0.12 meters per second. Overall losses were highest (over 30%) in the deepest underground mine due to weak rock layers and increased depth. The researchers aim to further reduce losses through optimizing
Abstract. Oil shale utilisation losses reach 70% in some cases. These are closely related to legislation, backfilling and waste rock usage. Much smaller sections include production of oil, electricity and chemicals in which most of the research and development is performed today. Current urgent topics for investigating, testing and developing of oil shale mining related questions are backfilling, mechanical extracting of shale, fine separation, selective separation and optimised drilling and blasting. Reducing oil shale losses will be more actual in the future, because the depth of mining increases and the taxes for resource and pollutants are increasing as well.
Environmental impact and potential use of coal fly ash andsub economical quar...LcNguyn140
This document summarizes a study that evaluated mixing sub-economical coal fly ash with quarry fines to form an aggregate that could be used as a partial substitute for sand in concrete. Coal fly ash and quarry fines are both industrial byproducts that are currently stockpiled due to high disposal costs. The study found that coal fly ash was effective at reducing leaching of potentially harmful trace elements from the quarry fines. Concrete containing the aggregate mixture displayed better mechanical properties compared to standard concrete. The results suggest that this method could provide an economically viable use for the coal fly ash and quarry fines byproducts from two major industries.
This document summarizes research on backfilling technologies for underground oil shale mines in Estonia. It discusses how backfilling mine voids with waste rock and ash can reduce environmental impacts by decreasing surface disposal needs. Studies included modeling mine spaces, testing fill materials, and evaluating technological schemes. Laboratory tests showed lower ash mixtures had higher strength. Mine tests indicated warming from large mixtures improved hardening. Overall the research aims to determine if backfilling is technically feasible under local mining conditions.
The document discusses mining waste reduction methods through several pilot projects in different countries in the Baltic Sea Region. The Estonian project involves a mobile unit for processing mining waste like oil shale waste rock into construction aggregates. The Swedish project aims to recover valuable and hazardous metals from mining and metal processing waste through a leaching and extraction process. The Finnish project involves a mobile module for testing the recycling of mining waste by grinding and classifying the material for potential use as an adsorbent. The Polish project develops artificial aggregates from mining waste for construction use through an agglomeration process. The overall goal is to promote sustainable waste management and resource efficiency in the mining industry through knowledge sharing between countries in the region.
Abstract — Mining waste reduction methods include all
mining processes beginning from resource distribution until
final yield in the plant. For comparing and testing possibilities of
mine waste reduction cooperation project has been set up aiming
to create a transnational network with regional networks. The
activities carried out on the regional and transnational level will
secure better access to knowledge, state-of-the-art technologies
and good practice to Small and Medium Enterprises active in
the mineral waste management & prevention sector. The project
addresses all the waste management challenges and
opportunities, which face the Baltic Sea Region mining industry,
which should be understood as extending to all forms of
extraction of natural non-renewable resources. The project
activities will be facilitated by the commitment to participate by
an additional 15 associated organizations representing mining
industry stakeholder associations and/or national government
bodies.
Karu improvement-of-technologies-for-mining-waste-managementMäeinstituut Ttü
This document summarizes a study on improving mining waste management technologies in the Baltic Sea region. It discusses how mining waste is generated and located. The main goals of mining waste management are to minimize waste production and maximize the use of best available technologies. The study examines different methods for reducing mining waste, such as testing various waste processing methods and choosing the most practical for each site. Specifically, the study describes designing pilot plants to process mining waste into aggregates for construction and to extract valuable metals. The document also analyzes the sources and standards for mining waste in Estonia, including waste from oil shale and limestone mining. Future research will focus on more environmentally friendly mining and utilizing old waste heaps as new raw materials.
Karu improvement-of-technologies-for-mining-waste-managementIngo Valgma
This document summarizes a study on improving mining waste management technologies in the Baltic Sea region. It addresses challenges related to large volumes of waste produced from mining activities and aims to identify solutions. The study examines 48 waste heaps in Estonia to characterize their composition and potential for re-use. Pilot projects are proposed to test constructing a mobile unit for processing waste into aggregates and extracting valuable metals. The goals are reducing waste and developing opportunities to use old waste as a resource. Additionally, the document analyzes specifications that result in high waste production from limestone and dolostone mining and evaluates composition of sand and gravel deposits to identify suitable quarry locations. Future work will focus on more environmentally friendly mining methods and determining how
Karu improvement-of-technologies-for-mining-waste-managementIngo Valgma
This document summarizes a study on improving mining waste management technologies in the Baltic Sea region. It identifies 48 mining waste sites in Estonia containing over 76 million cubic meters of waste rock and analyzes their characteristics. The study aims to locate waste heaps, analyze waste reduction methods, and find ways to use waste as a product. Two potential solutions explored are 1) constructing a mobile unit to process waste into aggregate for construction industries and 2) a pilot plant to extract valuable metals from waste. The document discusses standards for aggregates used in road construction that contribute to high waste production. It analyzes the composition of sand and gravel deposits to identify suitable mining locations. Future research will focus on environmentally friendly mining methods and determining how to
IRJET- Assessment of Slope Stability in Opencast Coal Mines using SoftwareIRJET Journal
This document discusses using FLAC/Slope software to analyze slope stability in an open cast coal mine. It summarizes the software's ability to model different failure mechanisms and assess slope stability through numerical modeling. The study area contains three coal seams within barakar sandstone formations. Geo-mechanical testing of the lithologies was performed to obtain properties like density and shear strength for the slope stability analysis. Parametric studies show slope angle significantly impacts stability, with steeper angles reducing stability.
IRJET- Experimental Study on Concrete Properties using Treated Waste Foundry ...IRJET Journal
This document summarizes an experimental study on the properties of concrete using treated waste foundry sand. Foundry sand is a byproduct of metal casting industries that is often dumped as waste. The study biologically treats the foundry sand using the fungus Aspergillus Niger to remove heavy materials. Concrete mixtures were made by partially replacing natural sand with treated waste foundry sand at levels of 10%, 20%, 30%, 40%, and 50%. The properties of the hardened concrete made with partial replacement were then tested.
Chemical Specifications for Raw Materials Used in The Kufa Cement Industry in...Jameel Tawfiq
This paper aims to provide background information on raw materials included in the cement industry that have chemically examined. The raw materials entering the factory examined, which include stone, crude oil, iron dust, sand, and gypsum, as it found that the total carbonate ratio is 89 percent as a weight ratio and the sulfide is smaller or equal to 1 percent as a weight ratio, and the magnesium carbonate is smaller or equal to 3 percent. For iron dust with sand, the total carbonates of the mixture were smaller or equal to 85 percent, and magnesium carbonate was smaller or equal to 3 percent. Silica oxide also examined in the sand were the results of the examination were greater than 85 percent. For sulfide oxide smaller than 1 percent, as well as for iron dust, the proportion of oxide Ferric is higher than 55 percent, the percentage of alumina oxide is less than 10 percent, silica oxide is less than 20 percent, as well as for crude oil, as it contains less than 4 percent of sulfide oxide, as well as primary and secondary gypsum examination, and it found that sulfide oxide is greater than 31 percent if the gypsum is Secondary and greater than 42 percent if the gypsum is primary. Materials are non-soluble smaller than 8 percent if it was secondary gypsum and less than 5 percent if the primary gypsum. Where these models examined and analyzed, and the storage location of the models examined were determined.
Behaviour of Lustrous Carbon Additives in Green Sand Castingijtsrd
The advent of High Volume, High Density and High Pressure Moulding Lines has changed the logistics of Molding Techniques and selection of additives significantly. Having 4 main ingredients, Base Sand, Bentonite, Lustrous Carbon Additives and Water, the properties of the Sand Mold resulting from this simple mixture to deliver target casting quality is complexly variable. Sand Control is an Art' as any foundry man will willingly emphasize. It is well accepted that no two foundry sand systems are the same. Even a single foundry Unit or foundry group having two or more molding lines, along with separate Sand preparation lines, whether in the same campus or in different locations, sand preparation and sand parameters will normally differ in each sand loop The role of quality in additives has therefore become even more important than when one could feel' the sand and make changes accordingly. Now, additives and ingredients have to be engineered precisely for the application with assured reproducibility in chemistry, grain fineness and other parameters. Pawan Prakash | Bhasker Shrivastava "Behaviour of Lustrous Carbon Additives in Green Sand Casting" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-4 | Issue-1 , December 2019, URL: https://www.ijtsrd.com/papers/ijtsrd29807.pdf Paper URL: https://www.ijtsrd.com/engineering/civil-engineering/29807/behaviour-of-lustrous-carbon-additives-in-green-sand-casting/pawan-prakash
Utilization of estremoz marbles sawing sludge in ceramic industry prelimin...Alexander Decker
This document summarizes a study on utilizing marble sawing sludge waste from the Estremoz marble industry in Portugal in ceramic mixtures. The study characterized the chemical composition of local clay and marble sludge. Mixtures with 2.5-20% sludge were prepared and evaluated. Incorporating sludge reduced plasticity but improved dimensional stability during drying and firing. Fired samples with up to 15% sludge showed increased strength due to reactions forming calcium phases, though porosity and absorption also increased. Preliminary results suggest sludge can be promisingly used in ceramics at 2.5-15% without significant processing changes.
Study on Effect of Fly Ash on Strength Characteristics of Black Cotton SoilIRJET Journal
This document summarizes a study on the effect of adding fly ash on the strength characteristics of black cotton soil. Black cotton soil is problematic for construction due to its high plasticity and shrink-swell potential. The study involved mixing black cotton soil with varying percentages of fly ash (0%, 10%, 20%, 30%, 40%, 50%) and testing the mixtures to determine the impact on soil properties. The tests showed that with increasing fly ash content, the liquid limit, plastic limit and plasticity index of the soil decreased, while optimum moisture content and maximum dry density increased, indicating improved engineering behavior. The differential free swell and California Bearing Ratio, measures of swelling potential and load-bearing capacity, also improved with higher fly ash
The document discusses possibilities for selective mining of kukersite oil shale in Estonia based on tests and studies. It finds that:
1) Selective and high selective mining methods have the potential to increase oil shale yield and decrease losses compared to traditional full seam extraction.
2) Productivity analyses show that surface miners can extract oil shale and limestone layers at rates of 591-736 tonnes per hour, depending on the material.
3) Sieving and particle size analyses found that selective mining produced oil shale particles predominantly between 0-400 mm in size, suitable for further processing.
Karu future of_oil_shale_mining_technology_in_estoniaMäeinstituut Ttü
The document summarizes research on future oil shale mining technology in Estonia. It finds that as mining conditions worsen and environmental taxes increase, higher quality oil shale with more homogeneous material properties will be required. One solution is selective mining and backfilling to decrease environmental impacts and opposition from local communities. Tests of selective surface mining and continuous underground mining show promise and establish criteria for evaluating and selecting the best available technologies for sustainable oil shale extraction in Estonia.
This document summarizes research on agricultural and industrial applications of fly ash from lignite combustion power plants in Greece. Chemical and mineralogical characterization of the fly ash revealed that it has an average grain size of a few to 200 micrometers, with glassy and spherical parts. Leaching experiments showed certain elements like sulfur, calcium, and potassium are mobile in the fly ash, while others like silicon, iron and magnesium exhibit low mobility. Preliminary results found that adding 5% fly ash to acidic soil can increase the pH to suitable levels for agriculture. The research aims to develop sustainable uses of fly ash in constructions, environment and agriculture applications.
IRJET- Application of Waste Plastic and Foundry Sand in Concrete BlocksIRJET Journal
This document discusses using waste plastic and foundry sand in concrete blocks to address environmental issues. It aims to partially replace fine sand in concrete mixes with processed plastic waste to tackle plastic waste and low recycling rates. Foundry sand produced from metal casting industries is also considered as a replacement as its improper disposal causes problems. The study will examine properties like slump, compressive strength, flexural strength, splitting tensile strength and elastic modulus of concrete blocks with replacements of plastic waste and foundry sand. Previous research found increased compressive strengths with foundry sand replacements up to 50% and normal workability with plastic replacements up to 20%. This research will provide an environmentally friendly way to utilize waste materials in construction.
This document summarizes research on surface mining technologies that can be used in zones of tectonic disturbances within the Estonian oil shale deposit. The researchers analyzed the geological conditions and determined the uniaxial compressive strength of rocks using indirect testing methods. A variety of excavation methods were considered, including digging, ripping, blasting, and hydraulic breaking. The researchers proposed feasible mining technologies for different zones based on the rock characteristics and strength parameters. Restrictions related to nearby inhabitation were also taken into account when assessing the appropriate excavation methods.
Similar to Pastarus paste-fills-technology-in-condition-of-estonian-oil-shale-mine (20)
This document contains 20 links from various search engines and websites searching for "Ingo Valgma CV". The links include search results from Google, Bing, Yahoo, and others. Several links also point directly to Ingo Valgma's blog and CV hosted on other websites. The document appears to be collecting search results and links related to finding an online CV for Ingo Valgma from different search tools and sources.
Temple of Asclepius in Thrace. Excavation resultsKrassimira Luka
The temple and the sanctuary around were dedicated to Asklepios Zmidrenus. This name has been known since 1875 when an inscription dedicated to him was discovered in Rome. The inscription is dated in 227 AD and was left by soldiers originating from the city of Philippopolis (modern Plovdiv).
THE SACRIFICE HOW PRO-PALESTINE PROTESTS STUDENTS ARE SACRIFICING TO CHANGE T...indexPub
The recent surge in pro-Palestine student activism has prompted significant responses from universities, ranging from negotiations and divestment commitments to increased transparency about investments in companies supporting the war on Gaza. This activism has led to the cessation of student encampments but also highlighted the substantial sacrifices made by students, including academic disruptions and personal risks. The primary drivers of these protests are poor university administration, lack of transparency, and inadequate communication between officials and students. This study examines the profound emotional, psychological, and professional impacts on students engaged in pro-Palestine protests, focusing on Generation Z's (Gen-Z) activism dynamics. This paper explores the significant sacrifices made by these students and even the professors supporting the pro-Palestine movement, with a focus on recent global movements. Through an in-depth analysis of printed and electronic media, the study examines the impacts of these sacrifices on the academic and personal lives of those involved. The paper highlights examples from various universities, demonstrating student activism's long-term and short-term effects, including disciplinary actions, social backlash, and career implications. The researchers also explore the broader implications of student sacrifices. The findings reveal that these sacrifices are driven by a profound commitment to justice and human rights, and are influenced by the increasing availability of information, peer interactions, and personal convictions. The study also discusses the broader implications of this activism, comparing it to historical precedents and assessing its potential to influence policy and public opinion. The emotional and psychological toll on student activists is significant, but their sense of purpose and community support mitigates some of these challenges. However, the researchers call for acknowledging the broader Impact of these sacrifices on the future global movement of FreePalestine.
This presentation was provided by Rebecca Benner, Ph.D., of the American Society of Anesthesiologists, for the second session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session Two: 'Expanding Pathways to Publishing Careers,' was held June 13, 2024.
How Barcodes Can Be Leveraged Within Odoo 17Celine George
In this presentation, we will explore how barcodes can be leveraged within Odoo 17 to streamline our manufacturing processes. We will cover the configuration steps, how to utilize barcodes in different manufacturing scenarios, and the overall benefits of implementing this technology.
This document provides an overview of wound healing, its functions, stages, mechanisms, factors affecting it, and complications.
A wound is a break in the integrity of the skin or tissues, which may be associated with disruption of the structure and function.
Healing is the body’s response to injury in an attempt to restore normal structure and functions.
Healing can occur in two ways: Regeneration and Repair
There are 4 phases of wound healing: hemostasis, inflammation, proliferation, and remodeling. This document also describes the mechanism of wound healing. Factors that affect healing include infection, uncontrolled diabetes, poor nutrition, age, anemia, the presence of foreign bodies, etc.
Complications of wound healing like infection, hyperpigmentation of scar, contractures, and keloid formation.
Gender and Mental Health - Counselling and Family Therapy Applications and In...PsychoTech Services
A proprietary approach developed by bringing together the best of learning theories from Psychology, design principles from the world of visualization, and pedagogical methods from over a decade of training experience, that enables you to: Learn better, faster!
A Visual Guide to 1 Samuel | A Tale of Two HeartsSteve Thomason
These slides walk through the story of 1 Samuel. Samuel is the last judge of Israel. The people reject God and want a king. Saul is anointed as the first king, but he is not a good king. David, the shepherd boy is anointed and Saul is envious of him. David shows honor while Saul continues to self destruct.
CapTechTalks Webinar Slides June 2024 Donovan Wright.pptxCapitolTechU
Slides from a Capitol Technology University webinar held June 20, 2024. The webinar featured Dr. Donovan Wright, presenting on the Department of Defense Digital Transformation.
2. Pastarus J.-R., Shommet J., Valgma I., Väizene V., Karu V. PASTE FILLS TECHNOLOGY IN CONDITION
OF ESTONIAN OIL SHALE MINE
sequence of the Ediacaran and Paleozoic sedimentary
rocks with age between 600Ma and 359Ma in Estonia
[2]. In the Harjumaa County there are being registered
16 carbonate stone deposits, four of them:
Vasalemma, Harku, Nabala, and Väo are listed as
deposits of all-country importance [21].
solid spheres of equal diameters the cubic and
rhombohedral pacing is possible (see Fig. 1) [1].
A
B
III BACKFILL TECHNOLOGY
In Estonian oil shale industry a wide assortment of
fill materials is available [6][7]. The whole processing
of oil shale from mining up to energy and oil
generates large amount of different waste:
Separation of limestone from the raw oil shale
generates large amounts of waste, which consists in
82...94 % of limestone and 6...18 % of oil shale
residues. These are stockpiled in form of cones (55 m
height) and total area of these piles is about 3.5 km2.
Limestone production is about 6.5 Mt per year.
1. The Estonian Thermal Power Plants use two
different oil shale combustion technologies:
pulverized firing (PF) and circulating fluidized bed
combustion (CFBC) technology. The compositional
and morphological variation between PF and CFBC
ashes [3] are principally controlled by firing
temperature
differences
between
combustion
technologies, and by grain size difference of oil shale
fuel. From the point of chemistry ash from oil shale
combustion is very similar to cement (with exception
in alkalinity) and there is no significant difference
between the potential environmental impacts from the
side of oil shale ash. About 4 km2 of the landfill are
occupied with ash ponds. Annual production is about
5 Mt. The determination of different ashes parameters
demands supplementary investigations and is under
construction.
2. In modern backfill technologies paste fills are
preferred [4][5]. It requires carefully selected grainsize distribution of solid particles and is able to flow
without sedimentation in pipes by low water content
(10...30 %). In this case backfill slurry has several
benefits:
Mixtures are able to set with lower or without
presence of additional binders.
Shorter binding times and better mechanical
properties.
Drainage and processing of bleed water eliminated.
Consequently, at a first approximation the
limestone aggregates properties determine the
behavior of backfill. Oil shale waste rock (limestone)
is produced during extraction as reject material from
separation plant and material from crushing and sizing
operations in aggregate production. It became clear
that production of aggregate produces large amount of
non-commercial aggregate [13].
IV GEOMETRICAL PARAMETERS OF AGGREGATES
The porosity of fill material consists of the void
spaces between solid fragments. If the fragments are
Fig. 1. Packing of the solid fragments [1], A – cubic packing; B –
rhombohedal packing
These two configurations represent the extremes of
porosity for arrangements of equidimensional sphere
with each sphere touching all neighboring spheres.
The porosity of well-rounded backfill materials, which
have been sorted so that they are all about the same
size, is independent of the particle size and falls in the
range of about 25.95% to 47.65%, depending upon the
packing [1]. If a backfill contains a mixture of grain
sizes, the porosity will be lowered. In this case the
smaller particles can fill the void spaces between the
larger ones. The wider the range of grain sizes, the
lower the resulting porosity.
In addition to grain-size sorting, the porosity of
material is affected by the shape of the grains [1].
Well-rounded grains may be almost perfect spheres,
but many grains are very irregular. Sphere-shaped
grains will pack more tightly and have less porosity
than particles of other shapes. The orientation of the
particles, if they are not spheres, also influence
porosity.
This phenomenon determines the bearing capacity
of backfill/pillar. Conformation of getting theoretical
result demands supplementary investigations of in situ
conditions.
A. Uniformity Coefficient
The uniformity coefficient of a material is a
measure of how well or poorly sorted it is. It is
presented by following formula[1]:
Cu d 60 / d10
(1)
where Cu – uniformity coefficient; d60 – grain size
that is 60% finer by weight; d10 – the grain size that is
10% finer by weight.
A sample with a uniformity coefficient less than 4
is well sorted, if it is more than 6 it is poorly sorted
[1].
The grain-size distribution curve and uniformity
coefficients for aggregate sizes 4/16, 16/32 and 32/63
mm have been determined. Fig. 2 demonstrates the
183
3. Pastarus J.-R., Shommet J., Valgma I., Väizene V., Karu V. PASTE FILLS TECHNOLOGY IN CONDITION
OF ESTONIAN OIL SHALE MINE
grain-size distribution curve for aggregate size 16/32
mm, mine Estonia.
determination of the applicability of limestone
aggregates as backfill material. The results of
investigations are presented in Table 2.
TABLE 2
OIL SHALE WASTE ROCK (AGGREGATES) PARAMETERS
Parameter
Measured
values
Recommended
values
Porosity of fill material, %
40 - 50
26 -48
Uniformity coefficient
1-2
<4, well sorted
Flakiness index, %
2 - 11
<35
In conclusion, it is visible that the aggregates from
oil shale mining waste rock can be used as a material
for backfilling the underground mined area. As long
as Estonian oil shale mines are located near to the
backfill required areas, other aggregates of limestone
and dolostone not suitable because of the location.
Fig. 2. Grain-size distribution curve. Aggregate size 16/32 mm,
mine Estonia
Investigation showed that uniformity coefficient for
all aggregate sizes is less than 4. For limestone and
dolostone uniformity coefficient is less than 3.
Consequently, the above mentioned aggregates are
well sorted and they satisfy the paste fills requirement.
B. Shape of the Coarse Aggregate
Flakiness Index is the percentage by weight of
particles in it, whose least dimension is less than 0.6
of its mean dimension. Flaky particles may have
adverse effect on concrete mix. For instance, flaky
particles tend to lower the workability of concrete mix
which may impair the long-term durability. The
results of flakiness index investigation in Estonian oil
shale mines and open casts are presented in Table 1.
TABLE 1
FLAKINESS INDEX OF WASTE ROCK AGGREGATE
Flakiness index Fl (average), %
Aggregate size,
mm
Mine
Estonia
Open cast
Aidu
Tondi-Väo Kareda
limestone dolostone
deposit
deposit
4/16
9
6
11
5*
16/32
6
3
7
4
32/63
4
2
10
10
*produced and tested aggregate 8/16 mm
Investigation showed that the flakiness index
depends on aggregate size for limestone aggregates of
Estonian oil shale mines. If the aggregate size
increases, the flakiness index decreases. In general,
the flakiness index of produced aggregates does not
exceed 35% and that depends on type of crushers and
number of crushing stages [12]. If the flakiness index
is less than 50% the negative influence on the strength
parameters of backfill is negligible.
V AGGREGATE PARAMETERS FOR BACKFILLING
VI RESULTS
In Estonian oil shale industry a wide assortment of
fill materials is available. In modern backfill
technologies paste fills are preferred. It required
careful selection of limestone aggregates as a
component part in fill mixture and is able to flow
without sedimentation in pipes by low water content.
The general parameters for paste fills technology are
porosity, uniformity coefficient and shape of coarse
aggregate. Getting results based on large amount of
theoretical investigations and of in situ experiments.
Porosity of fill material determines the amount of
power plant ash in mixture. Theoretically it is between
26 and 48% depending on packing of the solid
fragments. In real conditions, the fill material contains
a mixture of different grain sizes and shapes.
Investigation of in situ conditions showed that it is in
range of 40 – 50%, which guarantees optimum
amount of ash in mixture.
Strength parameters of backfill are determined by
uniformity coefficient of aggregates. It is calculated,
using grain-size distribution curve. Investigation
showed that uniformity coefficient is less than 4.
Consequently, all the aggregates are well sorted.
Shape of coarse aggregate influences on long term
durability of mixture and it is presented by flakiness
index. Laboratory tests showed that flakiness index for
all aggregate sizes is up to 11. If the flakiness index is
less than 35%, the negative influence on the strength
parameters of backfill is negligible.
Analysis showed that limestone aggregates suit best
for backfill technology in conditions of Estonian oil
shale mines. Usable investigation methods and getting
results are applicable for different aggregates as a
component part in fill mixture.
VII ACKNOWLEDGEMENTS
Estonian Science Foundation grants No. 8123
(2010-2013) “Backfill and waste management in
A complex method, including laboratory tests and
theoretical
investigations,
were
made
for Estonian oil shale industry” – mi.ttu.ee/ETF8123, SA
Archimedes project No. 3.2.0501.11-0025 (2012 –
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4. Pastarus J.-R., Shommet J., Valgma I., Väizene V., Karu V. PASTE FILLS TECHNOLOGY IN CONDITION
OF ESTONIAN OIL SHALE MINE
2015) “Sustainable and environmentally acceptable oil
shale mining” – mi.ttu.ee/etp, SA Archimedes project
No. 3.2.0501.10-0002 (2011-2014) “Basics of new
utilization process for oil shale combustion solid
waste” and Doctoral School of Energy and
Geotechnology II, DAR8130/1.2.0401.09-0082 –
mi.ttu.ee/doktorikool supported the research.
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