1. Illumination is vitally important in mining as it is always dark underground. Lighting allows miners to work safely and efficiently.
2. The main challenges for lighting underground are the dark, absorbent surfaces and restricted spaces that make even illumination difficult. Special equipment is also needed to avoid sparking in mines with flammable gases.
3. Modern cap lamps provide portable, helmet-mounted lighting for miners using rechargeable lead-acid or alkaline batteries. They aim to distribute light safely and minimize shadows and glare in hazardous underground conditions.
This document discusses lighting in mines and light physics concepts. It provides details on various types of lamps used in mines including acetylene lamps, flameproof safety torches, and electric cap lamps. It describes the layout of a lamp room and issues that may occur with cap lamps. Lighting arrangements and illumination levels for mines are also covered. Discharge lamps and fluorescent tubes for mine lighting are discussed. Testing for gas accumulation and percentage in mines using safety lamps is summarized.
The document discusses different types of ventilation systems used in mines: boundary, central, and combined. The boundary system uses unidirectional airflow from intake to return shafts located at the mine boundaries, requiring minimal ventilation control. It is most efficient but limited by mine size. The central system uses bidirectional airflow in parallel roadways separated by stoppings, allowing ventilation of larger areas but with greater airflow leakage.
This document discusses two mining methods: step mining and post-pillar mining. Step mining involves creating horizontal floors to allow equipment use for deposits that are too steeply inclined. Post-pillar mining uses regularly spaced pillars to extract inclined deposits between 20-55 degrees and allows filling of the mined space. It also discusses considerations for gallery dimensions, pillar dimensions and configurations, recovery strategies, equipment used, and operational aspects of board and pillar mining.
The document discusses underground metal mining methods. It describes operations like exploration, development, and mining of ore from a stope. Stoping methods are classified based on support as naturally supported, artificially supported, or caved stopes. Naturally supported methods include room and pillar mining and sublevel stoping. Artificially supported methods include shrinkage stoping and cut and fill stoping. Caved stope methods include sublevel caving and block caving. Parameters to consider when choosing a stoping method include geo-mechanical conditions, ore reserves and grades, costs, productivity, and available equipment.
The document provides information on various underground transport methods used in mines, including:
1) Rope haulage systems like direct rope haulage, main and tail rope haulage, and endless rope haulage.
2) Locomotive haulage using diesel, electric, or compressed air locomotives.
3) Conveyor systems like belt and chain conveyors.
4) Gravity or self-acting haulage which uses the weight of loaded carts to pull empty carts uphill.
1. Centrifugal pumps work by using centrifugal force to convert mechanical energy into hydraulic energy to move liquids through piping systems. They are the most common type of pumping machinery.
2. The main parts of a centrifugal pump are the impeller, casing, suction pipe with foot valve, and delivery pipe. Liquid enters at the center of the rotating impeller and is thrown outward by centrifugal force, converting kinetic energy into pressure energy.
3. Efficiency can be increased in multistage centrifugal pumps, which connect multiple impellers in series or parallel, allowing high heads or large discharges to be developed. Characteristic curves show the relationships between operating parameters.
This document discusses various techniques for raising, which is the vertical or steeply inclined excavation that connects different levels in underground mines. The key raising techniques discussed include open raising using drilling and blasting in short lengths, compartment method which divides the raise into sections, Alimak raise climber which uses a rack and pinion mechanism, longhole raising using long parallel drill holes, drop raising which uses large diameter blast holes, Jora hoist with a caged platform, and raise borers which drill and ream a circular raise without explosives. The Alimak raise climber is noted as generally the best adopted technique, first used in India in 1972.
This document discusses lighting in mines and light physics concepts. It provides details on various types of lamps used in mines including acetylene lamps, flameproof safety torches, and electric cap lamps. It describes the layout of a lamp room and issues that may occur with cap lamps. Lighting arrangements and illumination levels for mines are also covered. Discharge lamps and fluorescent tubes for mine lighting are discussed. Testing for gas accumulation and percentage in mines using safety lamps is summarized.
The document discusses different types of ventilation systems used in mines: boundary, central, and combined. The boundary system uses unidirectional airflow from intake to return shafts located at the mine boundaries, requiring minimal ventilation control. It is most efficient but limited by mine size. The central system uses bidirectional airflow in parallel roadways separated by stoppings, allowing ventilation of larger areas but with greater airflow leakage.
This document discusses two mining methods: step mining and post-pillar mining. Step mining involves creating horizontal floors to allow equipment use for deposits that are too steeply inclined. Post-pillar mining uses regularly spaced pillars to extract inclined deposits between 20-55 degrees and allows filling of the mined space. It also discusses considerations for gallery dimensions, pillar dimensions and configurations, recovery strategies, equipment used, and operational aspects of board and pillar mining.
The document discusses underground metal mining methods. It describes operations like exploration, development, and mining of ore from a stope. Stoping methods are classified based on support as naturally supported, artificially supported, or caved stopes. Naturally supported methods include room and pillar mining and sublevel stoping. Artificially supported methods include shrinkage stoping and cut and fill stoping. Caved stope methods include sublevel caving and block caving. Parameters to consider when choosing a stoping method include geo-mechanical conditions, ore reserves and grades, costs, productivity, and available equipment.
The document provides information on various underground transport methods used in mines, including:
1) Rope haulage systems like direct rope haulage, main and tail rope haulage, and endless rope haulage.
2) Locomotive haulage using diesel, electric, or compressed air locomotives.
3) Conveyor systems like belt and chain conveyors.
4) Gravity or self-acting haulage which uses the weight of loaded carts to pull empty carts uphill.
1. Centrifugal pumps work by using centrifugal force to convert mechanical energy into hydraulic energy to move liquids through piping systems. They are the most common type of pumping machinery.
2. The main parts of a centrifugal pump are the impeller, casing, suction pipe with foot valve, and delivery pipe. Liquid enters at the center of the rotating impeller and is thrown outward by centrifugal force, converting kinetic energy into pressure energy.
3. Efficiency can be increased in multistage centrifugal pumps, which connect multiple impellers in series or parallel, allowing high heads or large discharges to be developed. Characteristic curves show the relationships between operating parameters.
This document discusses various techniques for raising, which is the vertical or steeply inclined excavation that connects different levels in underground mines. The key raising techniques discussed include open raising using drilling and blasting in short lengths, compartment method which divides the raise into sections, Alimak raise climber which uses a rack and pinion mechanism, longhole raising using long parallel drill holes, drop raising which uses large diameter blast holes, Jora hoist with a caged platform, and raise borers which drill and ream a circular raise without explosives. The Alimak raise climber is noted as generally the best adopted technique, first used in India in 1972.
Mining Machinery Learning Material for DEegree and DiplomaBhaskar Naidu
This document provides curriculum information for a mining and mine surveying course. It includes chapter summaries on topics like transport of ore, winding in shafts, wire ropes, mine pumps, coal cutting machines, and electric power supply in mines. Sample questions are provided for each chapter, covering areas like types of rope haulage systems, attachments used for endless rope haulage, power requirements for haulage systems, and safety devices. Diagrams illustrate components like driving pulleys, surge wheels, and rope clips used for haulage. Tensioning arrangements like fixed, mobile, and gradient operated systems are also summarized.
TYPES OF VENTILATION SYSTEMS IN MINES - CENTRAL BOUNDARY U W ZANIL KUMAR KUDIRE
The document discusses five main types of mine ventilation systems: boundary, central, U, W, and Z. The boundary system has intake and return shafts located at the mine boundaries and allows unidirectional air flow. It requires minimal ventilation controls and has high efficiency. The central system has intake and return shafts located centrally and uses parallel airways separated by stoppings, allowing opposite air flows. It allows quicker development but has lower efficiency due to leakage. The U, W, and Z systems refer to specific configurations used for longwall mining where intake and return airways are arranged around the advancing longwall face.
Development and depillaring with continuous minerSafdar Ali
This document provides information about online test series, study materials and video lectures for various mining exams conducted in India. It also provides contact details for ordering mining books and for queries. The document discusses various continuous mining systems like longwall mining and room and pillar mining. It provides details about first workings, typical development layout, pillar extraction methods like split and fender mining and lift mining using breaker line supports. Equipment used in continuous miner panels like continuous miners, shuttle cars, feeder breakers and their specifications are also summarized.
This document discusses different types of fans used in mine ventilation. It describes centrifugal fans and axial flow fans, which are classified based on their location as main fans, auxiliary fans, or booster fans. Booster fans are large underground fans installed in series with main fans to boost air pressure. The document also discusses the components, operation, and blade types of centrifugal and axial fans. Maintaining reliable and energy efficient ventilation fans is important due to the high operating costs of powering them.
This document discusses roof support in underground coal mines. There are two main types of roof support: intrinsic supports like roof bolts that are installed within the roof, and standing supports like timber props that are installed between the roof and floor. Timber supports are commonly used in Indian coal mines due to low cost and availability, though metal supports offer higher load capacity. A case study examines how roof bolts were used with a specific layout and spacing in the Tandshi coal mine in India. Proper roof support is necessary to prevent roof collapse and protect miners from rock falls.
The basic principle of BG method is to be extract thick coal seams by drilling and blasting of roof and sides of gallery, which are driven at the bottom at the bottom of the seam at regular intervals.
Blasting gallery method is the appropriate method for the extraction of thick seam.
BLASTING OF RING HOLES PRODUCTION PER RING BLAST EXPLAINED
Method of working of continuous miner in underground coalSafdar Ali
The document discusses the method of working of a continuous miner in underground coal mining. It describes how a continuous miner continuously extracts coal from the working face using a cutting drum and conveyor system. It then discusses the different types of continuous miners and their main components. The summary is:
The document discusses the use of continuous miners for underground coal extraction. It describes how continuous miners use a rotating cutting drum and conveyor system to continuously extract coal from the working face. Different types of continuous miners are discussed along with their main components like the cutting head, loading mechanism, and conveyor system. Problems encountered and solutions implemented at various mining panels are also summarized.
pillar design in coal mines, different pillar design approaches, salmon versus sheorey formulae, panel stability, diffrent approaches, local mine stiffness
This document contains 61 multiple choice questions related to mining engineering. The questions cover topics such as blasting, explosives, ventilation, safety, surveying, geology and mining methods. Correct answer options are provided for each question. The purpose seems to be to test knowledge of key concepts and terminology in mining engineering.
The document discusses the design of pillars in underground coal mining. It notes that pillar failure can be gradual or sudden, with sudden failures causing disasters. Statutory guidelines exist for pillar dimensions but have limitations. The author proposes a modified formula to calculate pillar load that includes a dynamic load factor to account for loads during pillar extraction. Pillar strength is typically estimated using empirical formulas that the author critiques. The author suggests experience and site conditions be considered to better estimate pillar strength for ensuring stability of underground workings.
Bucket wheel excavators are large continuous mining machines used for soft to semi-hard materials like clay, sand, gravel, and coal. They have a large wheel with buckets that removes material in a continuous process. The largest bucket wheel excavators can be over 90 meters tall and 240 meters long, with a 21-meter diameter wheel. They are commonly used in strip mining and lignite mining to continuously remove overburden and deliver large volumes of material.
Natural ventilation in mines occurs due to temperature differences between the downcast and upcast shafts. It is a less effective method of ventilation than mechanical ventilation using fans. The natural ventilating pressure (NVP) can be determined through thermodynamic analysis of the pressure-volume indicator diagram of the mine ventilation system, which models it as a heat engine. Other practical methods also exist for estimating the NVP based on pressure and airflow measurements with the fan running and stopped.
1. Long hole drilling and blasting techniques are key to achieving high production rates in underground metal mines.
2. Precise long hole drilling allows for larger sublevel spacing and vertical crater retreat (VCR) mining which improves efficiency and productivity.
3. In VCR mining, parallel long holes are drilled and charged in horizontal slices which are blasted in a spherical pattern for effective fragmentation. Drilling is completed before slice blasting begins.
This document discusses various types of gases and dusts found in mines. It describes five common gas mixtures called damps: white damp (CO and air), black damp (CO2, N2 and air), stink damp (H2S and air), after damp (CO, CO2, CH4, O2, N2 and H2), and fire damp (methane and air). It also discusses mine dusts and provides a classification system for dusts based on their health hazards and explosion properties, including fiberogenic, carcinogenic, toxic, radioactive, and explosive dusts.
The document summarizes key details about Load Haul Dump (LHD) machines used in underground mining. LHDs are specialized loading machines that transport rock and ore long distances underground. They are available with either diesel or electric power sources. The internal components of LHDs include a diesel or electric motor, hydraulic systems, and safety features like fire suppression. External components are buckets for loading rock, mechanisms for dumping loads, and heavy duty tires. LHDs transport rock long distances underground in a cycle of loading, hauling, and dumping to remove ore efficiently from mines.
The document discusses the components and functioning of a flame safety lamp used for detecting methane gas in coal mines. It has an outer wire gauge and inner wire gauge to prevent flame from passing through, with a bonnet to protect the wire gauge. Fuels like kerosene and solvent are used. It works on the principle of preventing a flame from passing through the wire mesh to detect concentrations of methane gas and oxygen deficiencies through accumulation and percentage tests.
mine environment engineering
Intrinsic safety and flameproof apparatus in mines
research and development on explosions in mines
prevention of explosion in mines
In this ppt you will get all information regarding shaft sinking. Like what is permanent lining and temporary lining. How to decide shape of shaft, drilling blasting, support, lighting in shaft. Use of shaft and skips.
Criteria for selection of Board and pillar for multiple seamsAsim kumar Satapathy
So the main purpose of this project is to focus on the selection criteria of Bord and Pillar workings without compromising the safety factor in multiple seam.
This document discusses the Bord and Pillar method of coal mining. It involves leaving pillars of coal as support during initial mining, allowing for around 20% output. Later, the pillars can be extracted to increase output to 60%. The document focuses on the process of depillaring, or extracting the remaining coal from the pillars. This involves techniques like depillaring with stowing, where the emptied areas are filled with incombustible materials to control subsidence. Principles of safe pillar extraction are outlined, along with case studies and conclusions that depillaring must be done scientifically and safely according to regulations.
The document discusses several types of batteries used in automotive electrical systems, including their working principles and chemical reactions. It provides details on aluminium-air batteries, noting their high energy density but issues with high anode cost and non-rechargeability. It also summarizes sodium-sulfur batteries, nickel-cadmium batteries, alkaline batteries, and discusses maintainable versus maintenance-free battery designs as well as common battery problems like physical damage, undercharging, and sulphation.
This document describes how to build a simple hydrogen fuel cell and discusses its potential use in fuel cell vehicles. It contains instructions to construct a basic hydrogen fuel cell using platinum wire electrodes, a battery clip, and a glass of water. Touching a 9-volt battery to the clip causes electrolysis, splitting the water into hydrogen and oxygen bubbles at the electrodes. The document also provides a brief overview of the redox reactions that power fuel cells, noting hydrogen splits to protons and electrons at the anode while oxygen, protons, and electrons combine to form water at the cathode. Fuel cells use catalysts to increase the reaction rate and an electrolyte to selectively permit ion passage between electrodes. The goal is to develop hydrogen fuel
Mining Machinery Learning Material for DEegree and DiplomaBhaskar Naidu
This document provides curriculum information for a mining and mine surveying course. It includes chapter summaries on topics like transport of ore, winding in shafts, wire ropes, mine pumps, coal cutting machines, and electric power supply in mines. Sample questions are provided for each chapter, covering areas like types of rope haulage systems, attachments used for endless rope haulage, power requirements for haulage systems, and safety devices. Diagrams illustrate components like driving pulleys, surge wheels, and rope clips used for haulage. Tensioning arrangements like fixed, mobile, and gradient operated systems are also summarized.
TYPES OF VENTILATION SYSTEMS IN MINES - CENTRAL BOUNDARY U W ZANIL KUMAR KUDIRE
The document discusses five main types of mine ventilation systems: boundary, central, U, W, and Z. The boundary system has intake and return shafts located at the mine boundaries and allows unidirectional air flow. It requires minimal ventilation controls and has high efficiency. The central system has intake and return shafts located centrally and uses parallel airways separated by stoppings, allowing opposite air flows. It allows quicker development but has lower efficiency due to leakage. The U, W, and Z systems refer to specific configurations used for longwall mining where intake and return airways are arranged around the advancing longwall face.
Development and depillaring with continuous minerSafdar Ali
This document provides information about online test series, study materials and video lectures for various mining exams conducted in India. It also provides contact details for ordering mining books and for queries. The document discusses various continuous mining systems like longwall mining and room and pillar mining. It provides details about first workings, typical development layout, pillar extraction methods like split and fender mining and lift mining using breaker line supports. Equipment used in continuous miner panels like continuous miners, shuttle cars, feeder breakers and their specifications are also summarized.
This document discusses different types of fans used in mine ventilation. It describes centrifugal fans and axial flow fans, which are classified based on their location as main fans, auxiliary fans, or booster fans. Booster fans are large underground fans installed in series with main fans to boost air pressure. The document also discusses the components, operation, and blade types of centrifugal and axial fans. Maintaining reliable and energy efficient ventilation fans is important due to the high operating costs of powering them.
This document discusses roof support in underground coal mines. There are two main types of roof support: intrinsic supports like roof bolts that are installed within the roof, and standing supports like timber props that are installed between the roof and floor. Timber supports are commonly used in Indian coal mines due to low cost and availability, though metal supports offer higher load capacity. A case study examines how roof bolts were used with a specific layout and spacing in the Tandshi coal mine in India. Proper roof support is necessary to prevent roof collapse and protect miners from rock falls.
The basic principle of BG method is to be extract thick coal seams by drilling and blasting of roof and sides of gallery, which are driven at the bottom at the bottom of the seam at regular intervals.
Blasting gallery method is the appropriate method for the extraction of thick seam.
BLASTING OF RING HOLES PRODUCTION PER RING BLAST EXPLAINED
Method of working of continuous miner in underground coalSafdar Ali
The document discusses the method of working of a continuous miner in underground coal mining. It describes how a continuous miner continuously extracts coal from the working face using a cutting drum and conveyor system. It then discusses the different types of continuous miners and their main components. The summary is:
The document discusses the use of continuous miners for underground coal extraction. It describes how continuous miners use a rotating cutting drum and conveyor system to continuously extract coal from the working face. Different types of continuous miners are discussed along with their main components like the cutting head, loading mechanism, and conveyor system. Problems encountered and solutions implemented at various mining panels are also summarized.
pillar design in coal mines, different pillar design approaches, salmon versus sheorey formulae, panel stability, diffrent approaches, local mine stiffness
This document contains 61 multiple choice questions related to mining engineering. The questions cover topics such as blasting, explosives, ventilation, safety, surveying, geology and mining methods. Correct answer options are provided for each question. The purpose seems to be to test knowledge of key concepts and terminology in mining engineering.
The document discusses the design of pillars in underground coal mining. It notes that pillar failure can be gradual or sudden, with sudden failures causing disasters. Statutory guidelines exist for pillar dimensions but have limitations. The author proposes a modified formula to calculate pillar load that includes a dynamic load factor to account for loads during pillar extraction. Pillar strength is typically estimated using empirical formulas that the author critiques. The author suggests experience and site conditions be considered to better estimate pillar strength for ensuring stability of underground workings.
Bucket wheel excavators are large continuous mining machines used for soft to semi-hard materials like clay, sand, gravel, and coal. They have a large wheel with buckets that removes material in a continuous process. The largest bucket wheel excavators can be over 90 meters tall and 240 meters long, with a 21-meter diameter wheel. They are commonly used in strip mining and lignite mining to continuously remove overburden and deliver large volumes of material.
Natural ventilation in mines occurs due to temperature differences between the downcast and upcast shafts. It is a less effective method of ventilation than mechanical ventilation using fans. The natural ventilating pressure (NVP) can be determined through thermodynamic analysis of the pressure-volume indicator diagram of the mine ventilation system, which models it as a heat engine. Other practical methods also exist for estimating the NVP based on pressure and airflow measurements with the fan running and stopped.
1. Long hole drilling and blasting techniques are key to achieving high production rates in underground metal mines.
2. Precise long hole drilling allows for larger sublevel spacing and vertical crater retreat (VCR) mining which improves efficiency and productivity.
3. In VCR mining, parallel long holes are drilled and charged in horizontal slices which are blasted in a spherical pattern for effective fragmentation. Drilling is completed before slice blasting begins.
This document discusses various types of gases and dusts found in mines. It describes five common gas mixtures called damps: white damp (CO and air), black damp (CO2, N2 and air), stink damp (H2S and air), after damp (CO, CO2, CH4, O2, N2 and H2), and fire damp (methane and air). It also discusses mine dusts and provides a classification system for dusts based on their health hazards and explosion properties, including fiberogenic, carcinogenic, toxic, radioactive, and explosive dusts.
The document summarizes key details about Load Haul Dump (LHD) machines used in underground mining. LHDs are specialized loading machines that transport rock and ore long distances underground. They are available with either diesel or electric power sources. The internal components of LHDs include a diesel or electric motor, hydraulic systems, and safety features like fire suppression. External components are buckets for loading rock, mechanisms for dumping loads, and heavy duty tires. LHDs transport rock long distances underground in a cycle of loading, hauling, and dumping to remove ore efficiently from mines.
The document discusses the components and functioning of a flame safety lamp used for detecting methane gas in coal mines. It has an outer wire gauge and inner wire gauge to prevent flame from passing through, with a bonnet to protect the wire gauge. Fuels like kerosene and solvent are used. It works on the principle of preventing a flame from passing through the wire mesh to detect concentrations of methane gas and oxygen deficiencies through accumulation and percentage tests.
mine environment engineering
Intrinsic safety and flameproof apparatus in mines
research and development on explosions in mines
prevention of explosion in mines
In this ppt you will get all information regarding shaft sinking. Like what is permanent lining and temporary lining. How to decide shape of shaft, drilling blasting, support, lighting in shaft. Use of shaft and skips.
Criteria for selection of Board and pillar for multiple seamsAsim kumar Satapathy
So the main purpose of this project is to focus on the selection criteria of Bord and Pillar workings without compromising the safety factor in multiple seam.
This document discusses the Bord and Pillar method of coal mining. It involves leaving pillars of coal as support during initial mining, allowing for around 20% output. Later, the pillars can be extracted to increase output to 60%. The document focuses on the process of depillaring, or extracting the remaining coal from the pillars. This involves techniques like depillaring with stowing, where the emptied areas are filled with incombustible materials to control subsidence. Principles of safe pillar extraction are outlined, along with case studies and conclusions that depillaring must be done scientifically and safely according to regulations.
The document discusses several types of batteries used in automotive electrical systems, including their working principles and chemical reactions. It provides details on aluminium-air batteries, noting their high energy density but issues with high anode cost and non-rechargeability. It also summarizes sodium-sulfur batteries, nickel-cadmium batteries, alkaline batteries, and discusses maintainable versus maintenance-free battery designs as well as common battery problems like physical damage, undercharging, and sulphation.
This document describes how to build a simple hydrogen fuel cell and discusses its potential use in fuel cell vehicles. It contains instructions to construct a basic hydrogen fuel cell using platinum wire electrodes, a battery clip, and a glass of water. Touching a 9-volt battery to the clip causes electrolysis, splitting the water into hydrogen and oxygen bubbles at the electrodes. The document also provides a brief overview of the redox reactions that power fuel cells, noting hydrogen splits to protons and electrons at the anode while oxygen, protons, and electrons combine to form water at the cathode. Fuel cells use catalysts to increase the reaction rate and an electrolyte to selectively permit ion passage between electrodes. The goal is to develop hydrogen fuel
This document provides an overview of different types of batteries, including primary batteries that cannot be recharged, and secondary batteries that can be recharged. It discusses common primary batteries like dry cells and mercury cells. For secondary batteries it covers nickel-cadmium, nickel-metal hydride, lithium-ion, solid state, and molten salt batteries. For each type it provides details on the chemical reactions, components, advantages and disadvantages, and applications. The document is an educational resource on batteries intended to explain their basic functions and characteristics.
The document discusses various types of chemical energy storage batteries. It begins by defining batteries as devices that convert chemical energy to electrical energy through electrochemical reactions. Batteries are then classified as either primary (non-rechargeable) or secondary (rechargeable) batteries. Several common battery types are described in detail, including lead-acid, nickel-cadmium, lithium-ion, sodium-sulfur, and zinc-bromine batteries. Their basic workings, advantages, and disadvantages are summarized. The document also discusses fuel cells as another method of chemical energy storage.
Cells and batteries produce electricity through chemical reactions. Primary cells like zinc-carbon and alkaline cells are disposable, while secondary cells like lead-acid batteries can be recharged. Zinc-carbon cells use zinc and manganese dioxide electrodes with a paste electrolyte, producing 1.5 volts. Alkaline cells last longer with zinc and manganese dioxide electrodes in an alkaline electrolyte. Fuel cells like alkaline fuel cells continuously supply reactants to produce electricity, avoiding energy losses of power stations. Fuel cells may power vehicles as an alternative to combustion engines.
rechargable batteries and lead acid batteryTANISHQBAFNA
Lead-acid batteries were the first rechargeable battery invented in 1859. They work through chemical reactions between lead and lead dioxide electrodes and sulfuric acid electrolyte. Overcharging can produce explosive gases. Lead-acid batteries are used in many applications due to their low cost. Nickel-cadmium batteries were introduced in the 1960s and have higher energy density than lead-acid. They use cadmium and nickel oxide electrodes with an alkaline electrolyte but cadmium is toxic. Nickel metal hydride batteries replaced cadmium with hydrogen-absorbing alloys and have higher energy density than NiCd with no toxicity. Lithium ion batteries have the highest energy density of any rechargeable battery due to lith
BATTERY.pptx presentation Introduction to Electric vehiclesAlistairPinto
Batteries contain chemical energy that is converted to electrical energy through redox reactions between positive and negative electrodes separated by an electrolyte. Common battery types for electric vehicles include lead-acid, nickel-cadmium, nickel-metal hydride, lithium-ion, and lithium polymer. These differ in materials used for electrodes and electrolytes, as well as their energy densities, costs, and environmental impacts. Lithium-ion batteries currently dominate the electric vehicle market due to their high energy density and lack of memory effect.
This presentation discusses lead acid batteries. It describes lead acid batteries as a type of secondary cell that can be recharged through a reversible chemical reaction. The document outlines the construction of lead acid batteries, including their lead and sulfuric acid components, plastic case, lead plates coated in lead dioxide and spongy lead, and separator. It also explains the four stages of the battery's working: charged, discharging, discharged, and recharging.
The document outlines the objectives, methods, workings, and conclusions of a study on solar mobile chargers. The objectives were to study the basic operations of solar mobile chargers, understand their advantages and limitations, and maximize their use. The methods included using components like solar panels, voltage regulators, switches, and resistors. It then discusses how solar panels convert sunlight to electrical energy through the photovoltaic effect and how this powers the mobile charger. In conclusion, solar chargers are portable, emission-free, and help conserve energy, but they are expensive and charge slower than traditional chargers.
The document outlines the objectives, methods, workings, and conclusions of a study on solar mobile chargers. The objectives were to study the basic operations of solar mobile chargers, understand their advantages and limitations, and maximize their use. The methods included using components like solar panels, voltage regulators, switches, and resistors. It then discusses how solar panels convert sunlight to electrical energy through the photovoltaic effect and how this powers the mobile charger. In conclusion, solar chargers are portable, efficient, and environmentally friendly but their costs remain higher than traditional chargers.
Zinc-air batteries use zinc as the anode and oxygen from the air as the cathode. They have a high energy density and range from button cells to applications in electric vehicles. Zinc reacts with hydroxyl ions at the anode to form zincate, releasing electrons. The zincate then decays into zinc oxide and water, which is recycled at the cathode. Reactions produce around 1.35-1.4 volts.
This document summarizes a student paper on paper batteries. It introduces paper batteries as an energy storage device made from carbon nanotubes and cellulose paper. Conventional lithium-ion batteries are described as having disadvantages like corrosion, temperature control issues, and lack of eco-friendliness. Carbon nanotubes and cellulose paper are presented as the key materials used to build paper batteries due to their properties like strength and flexibility. The document outlines the construction and working of paper batteries along with their applications and advantages such as being light weight, flexible, reusable, and non-toxic. It concludes that paper batteries could power small devices now and potentially larger things like cars in the future.
Reel and Umbilical Training for Subsea Hose Reels and Umbilicalswevans1
This document provides an overview of reels and umbilicals used to handle long lengths of cables connecting offshore platforms to subsea equipment. It discusses:
1) The main components of reels, including large drums to store umbilicals, drive trains to power the drums, emergency brakes, and level wind guides.
2) Umbilicals can contain many cores transmitting power, signals, and fluids over long distances. Common cores include hydraulic lines, electrical cables, and fiber optic lines.
3) Proper handling, maintenance, and testing of reels and umbilicals is important for safety and performance. Regular inspections and replacement of worn parts can reduce operational costs over the long run.
Title: Advancements in Electrode Materials for Automotive Batteries: A Comprehensive Review
Abstract:
The automotive industry is rapidly transitioning towards electric propulsion systems to mitigate environmental impacts and reduce dependency on fossil fuels. Central to this shift are advancements in battery technology, particularly in electrode materials, which play a critical role in determining battery performance, energy density, and lifespan. This comprehensive review explores the latest developments in electrode materials for automotive batteries, encompassing lithium-ion, solid-state, and beyond lithium-ion technologies. We delve into the fundamental principles governing electrode material selection, discuss current challenges, and analyze emerging trends such as silicon-based anodes, sulfur cathodes, and solid electrolytes. Through an extensive examination of recent research and commercial developments, we provide insights into the future direction of electrode materials for automotive batteries, highlighting key areas for further research and innovation.
1. Introduction:
- Overview of the importance of electrode materials in automotive batteries
- Transition towards electric vehicles (EVs) and the role of batteries
- Purpose and scope of the review
2. Fundamentals of Battery Electrodes:
- Electrochemical principles underlying battery operation
- Role of electrodes in battery performance
- Requirements for automotive applications: energy density, power density, longevity, and safety
3. Lithium-Ion Batteries:
- Overview of lithium-ion battery architecture
- Current electrode materials: graphite anodes, lithium cobalt oxide (LCO), lithium iron phosphate (LFP), etc.
- Challenges and limitations: capacity degradation, safety concerns, resource availability
- Recent advancements in electrode materials for lithium-ion batteries
4. Beyond Lithium-Ion Batteries:
- Need for higher energy density and sustainability
- Emerging alternatives: lithium-sulfur (Li-S), lithium-air (Li-O2), sodium-ion (Na-ion), potassium-ion (K-ion) batteries
- Electrode materials for non-lithium systems: sulfur cathodes, sodium-ion anodes, etc.
- Comparative analysis of different beyond lithium-ion technologies
5. Silicon-Based Anodes:
- Potential of silicon as a high-capacity anode material
- Challenges: volume expansion, cycling stability, Coulombic efficiency
- Strategies to mitigate silicon anode limitations: nanostructuring, alloying, coatings
- Progress in commercialization and integration into automotive batteries
6. Solid-State Batteries:
- Advantages of solid-state electrolytes over liquid electrolytes
- Materials for solid-state electrolytes: sulfides, oxides, polymers
- Solid-state electrode materials: lithium metal, sulfides, etc.
- Recent breakthroughs in solid-state battery technology and their implications for automotive applications
7. Challenges and Opportunities:
- Scalability
The document discusses the history and development of batteries from ancient times to modern lithium-ion batteries. It covers topics such as the first batteries discovered in ancient Mesopotamia over 2,000 years ago, the invention of rechargeable lead-acid batteries in 1859, and the development and commercialization of lithium-ion batteries starting in the 1990s. It also summarizes the basic workings of lithium-ion batteries and discusses capacity, charging, applications, advantages, limitations, and myths regarding lithium-ion batteries. Research into nanotechnology and new battery materials like silicon is also briefly mentioned to improve performance and safety.
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3. ILLUMINATION
• Illumination is the light incident on the surface of
the object.
• No single factor is of more importance to the
mining industry than lighting.
• Under natural conditions it is always dark below
ground, and all light must be produced
artificially.
Furthermore, mining is a hazardous calling
requiring a continual state of awareness and
ability to recognize danger from many sources
3
4. • Lighting is vitally necessary underground,
and it is usually very important to ensure
that there are no failures , and that the
lamp used is as efficient as possible —
both for safety and for good morale.
4
5. • A man can work efficiently and give satisfactory
results only if he can see
• what he is doing and is not hampered by
inadequate illumination or annoying shadows.
• Lighting has a serious effect upon morale and
plays an important part in improving operating
conditions below ground.
5
6. • emphasis was generally laid upon the economic
factors involved, and lamps were operated as
cheaply as possible.
• The main difficulty arises from the presence
below ground of inflammable gas, which
requires all the lamps and fittings used
to be specially designed to eliminate the risk of
ignition.
• Such equipment and may prohibit the general
use of mains-fed equipment.
6
7. • The second important obstacle is the nature of the
surface surrounding the working places.
• In their natural states these are dark in colour and are
highly absorbent to the light falling upon them.
• Coal absorbs about 95 % of the incident light,
• shale and carboniferous rocks, about 75%; and
• props, etc., about 85%,
• compared with some 40% absorbed by whitewashed
surfaces.
7
8. • The problem is also aggravated by the restricted and
congested nature of the working places.
• The roadways comprise comparatively narrow tunnels
which are not easy to illuminate without glare.
• Coal-faces are frequently low in height and the
• presence of machinery and roof supports, all of which
cast shadows, make even illumination virtually
impossible.
8
9. • The only solution here appears to lie in the
use of larger light sources, but
• the avoidance of undesirable extremes of
light and dark and of glare is difficult, and
the best result can be obtained only by
compromise.
9
10. • One of the principal difficulties in
assessing visibility in mines
• lack of agreed standards and methods of
assessing the parameters involved;
• attempts are to be made to achieve
international agreement on this matter.
10
11. • One adverse effect of insufficient lighting
in mines is the incidence of the eye
disease of miners' nystagmus.
• This is usually evidenced by oscillations of
the eyeballs,
• slow adaptation of the eyes to both light
and dark and other neurotic effects..
• The sufferers also have a marked dislike
for bright light
11
12. • 'portable lighting' includes those systems
which involve units carried by the users,
as distinct from permanent and semi-
permanent fittings requiring a mains
source of power.
12
14. 14
Oil wick lamps improved safety
by containing open flames. Costs
were also lower, and miners
found them easier to use than
candles. Oil wick lamps improved safety
by containing open flames. Costs
were also lower, and miners
found them easier to use than
candles.
15. 15
Carbide lamps
The transition to helmet-mounted
lighting began with the introduction
of the carbide lamp.
The transition to helmet-mounted
lighting began with the introduction
of the carbide lamp.
16. 16
Incandescent Lights
The introduction of the
incandescent lamp eliminated
concerns about open
flames within the mine.
The light from a small, steadily
burning incandescent filament
was much more controllable
than the light from an open
flame. Enclosed within a
directional reflector, it became
the standard, unchanged to
this day.
17. 17
Light Emitting Diodes (LEDs)
• LEDs are semi-conductors; they don't have a filament that will burn out.
•They are illuminate by the movement of electrons in a semiconductor.
18. Cap lamps
• Cap lamp or lamp : The complete lighting set.
• Battery : The electricity storage unit, usually carried
on a belt and consisting of two lead-acid cells.
• Cell : One lead-acid unit consisting of positive and
negative plates, and nominally two volts.
• Headset : The part that normally attaches to the
helmet
18
19. • The lead-acid battery has many advantages over other
rechargeable batteries
• the most important : fairly high power to weight ratio; low
cost; high electrical efficiency : flat discharge voltage
characteristics; simple self-service charging capability;
and finally, the electrolyte is far less dangerous than
that used in alkali batteries,
On the other hand, lead-acid batteries are perhaps more
susceptible to incorrect charging than alkali types,
though if the right method is used overcharging cannot
occur and reliable performance should be obtained
19
20. • Modern lamps have a capacity of over 10
Amp-hours, weigh less than 2.5 Kg, and
are extremely
• reliable if correctly treated
20
21. • Cap lamps are constructed with the bulb carried in a headpiece
affixed to the user's helmet, while the battery, supported by
a belt, is carried on the miner's back.
Headpieces are of plastic or metal, and bulb and reflector
assemblies are of similar design in all types.
Features of the newer models are their compactness and light
weight.
It is important that the weight should be small and the centre of
gravity should be as near to the helmet fixing as possible
• The lens glasses are of armoured glass approved by the
Regulatory authorities, and they must carry an appropriate
marking.
• Lens rings are of metal or plastic and screw or clip into position
21
22. Construction of cap lamps
• A cell in a cap lamp battery consists of three plates held apart by
porous separators and surrounded by a strong shock resistant case
which also serves to contain the acid electrolyte (see Fig. 1a).
• The centre plate is the positive plate which when charged is mainly
lead dioxide (PbO2 ). The construction of modern positive plates is
tubular, each tube — as shown in Fig.— consisting of an antimonial
lead alloy spine (for strength) surrounded by the active material
which is packed as a powder into the outer sleeves that hold it
together.
• The two outer plates are formed from the negative active material,
lead (Pb). These plates are described as being of pasted
construction since part of the manufacturing process consists
of making a paste of lead compounds,
• sulphuric acid, and various additives, which are then formed onto
the basic grids of the plates
• Modern separators are highly absorbent in order to reduce as far as
possible the free electrolyte in the cell, and are now exclusively
synthetic. Their thickness means that the internal resistance of a cell
is fairly high when compared to other types of lead-acid cells - being
about 0.05 ohms
22
25. • The cases of batteries are moulded in hard synthetic rubber or
plastics such as polycarbonate. Incorporated in all capjamp batteries
are topping-up holes and non-spill vents which allow any gas
released during charging to escape, but keep acid inside the cells
even if the battery is inverted.
• The acid electrolyte is approximately 20% sulphuric acid of high
purity, and batteries are normally protected by a two or three
ampere fuse.
• The non-spill vents are only effective if the electrolyte level is
correct.
• Acid leak from the vents may be noted after the battery has been
immersed in water, since the cooling of the air inside the battery
• causes water to be forced in, hence diluting and contaminating the
electrolyte.
• The electrolyte level rises, so leakage occurs, especially during
charging.
• This can be avoided by blocking or covering the vents before
immersion (taking care that any thing used cannot be sucked up into
the battery).
The vents must be cleared before charging.
25
26. The Discharge Process
• A fully charged cell has the positive active material PbO2 , the
negative active material Pb, and the electrolyte at its strongest with
a specific gravity of about 1.29 (pure water has a s.g. of 1.00).
• When put on load — that is, when the lamp is switched on — each
cell will begin to discharge from a starting voltage of nominally 2
volts.
• During discharge, the positive and negative plates are transformed
slowly into lead sulphate (PbSO4) as shown
• The sulphur in this compound must of course come from the
sulphuric acid, so the electrolyte becomes more diluted with the s.g.
dropping eventually to about 1.10 during a normal discharge.
• In general purpose lead-acid batteries the specific gravity is a very
accurate guide to the state of discharge, however in cap lamp
batteries there is very little free electrolyte, and so measuring the
s.g. is not usually a practical proposition.
26
29. • During this process the internal resistance
of a battery rises from about 0.1 to 0.15
ohm, the actual value depending on its
condition and age —
• in general a battery which is old or in bad
condition will have a higher internal
resistance.
29
30. • A typical discharge curve is shown . Batteries should not
normally be discharged below 1.7 volts per cell at which
point the main beam will be noticeably dimmer than full
brightness.
• If discharged below this voltage, the battery should be
recharged as soon as possible as otherwise sulphation
will become pronounced far more quickly than usual.
• In addition sulphation will occur in normal use if a battery
is left in a discharged state for long periods —It will be
seen from the discharge curve that the battery voltage
remains close to 4 volts for most of the time.
• This is an important point as it means that bulbs can be
used close to their optimum operating point for most of
the period of discharge, which makes for high lighting
efficiency.
30
31. Voltage discharge curves of batteries
(a) Lead-acid battery discharging through 0-8 amp (rating) bulb.
(/>) Nickel-cadmium battery discharging through 1 0 amp (rating) bulb
31
32. • It will be seen from the discharge curve that the
battery voltage remains close to 4 volts for most
of the time.
• This is an important point as it means that bulbs
can be used close to their optimum operating
point for most of the period of discharge, which
makes for high lighting efficiency.
• The electrical power efficiency of a lead-acid
battery is extremely high. 75% of the power put
in during charge may be used on discharge,.
• The amp-hour efficiency (Amp-hours
output/Amp-hours input) is even higher —
typically 90%.
• The efficiency and capacity of a battery is
reduced at low temperatures, both being as
much as 10% less at 0°C than at 15°C.
32
33. • Reflectors are generally of anodized aluminium, although treated
plastic reflectors are also in use. The shape of the reflector is
approximately parabolic and the light distribution is determined by
the degree of matting of the reflector surface.
• Generally, a semi-matt finish having a reflector ratio of 25 : 1 *
is deemed suitable for the ordinary workman, but polished
reflectors with ratios of 50 or 100 : 1 are in use for officials and
specialized tradesmen and are increasingly used by men engaged
in mechanical mining operations
• * The reflection ratio of a cap-lamp reflector is the ratio of the
maximum candlepower of the beam (usually at or near the centre) to
the average candle-power over the solid illuminated angle
33
34. • Main bulbs used in cap lamps may have either single or double
filaments, and are filled with krypton; the light output is about
40 lumens.
Some cap-lamp headpieces include a small auxiliary
bulb having a lower current rating than the main bulb, which acts
as a standby in case of failure of the main filament and can be
used to conserve the charge of the battery in an emergency.
• Alternatively, the auxiliary filament may be included in the main
bulb, but it is generally accepted that a second filament is advisable.
• A switch is usually incorporated in the headpiece, to select the
main or pilot filament or the 'off' position.
34
35. • The headpiece must be locked against unauthorized opening
by a magnetic lock, lead seal or special shrouded screw covered
with a wax seal.
• The headpiece is connected to the battery by a cable of specified
design
• The characteristics of the cable are important, since the
performance and the safety of the lamps are dependent upon it.
• very satisfactory cables are available which has an average life of 2-
3 years, dependent upon the severity of the conditions of its use.
• The cable is secured to the headpiece and battery in a variety of
ways in different lamps, but in all cases the arrangement must be
strong enough to withstand a steady pull of 20 kgs.
35
36. Lead-Acid Batteries for Cap
Lamps.
• The lead-acid batteries used with cap lamps are of two types,
differing principally in the design of the positive plates.
One type of battery has tubular positive plates in which the active
material is packed around lead splines and retained by slotted
rubber tubes.
• The other type employs flat positive plates of the pasted-grid type.
The negative plates in both batteries are flat,
the grids being in the form of a lattice.
The separators are highly absorbent, so that there is little free acid
in the battery. The latter feature, coupled with a special venting
arrangement, provides an unspillable battery which 'breathes' to
atmosphere.
• It is possible to charge such batteries without dismantling the lamps
36
37. • The positive and negative plates are
housed in a hard-rubber box which
constitutes the outer container.
• Topping-up with distilled water is
accomplished by removing a filler plug and
gasket on the side of the battery, which
uncovers two holes giving access to the
two cells.
37
38. • A typical discharge curve for a 4-volt lead-
acid cap-lamp battery, supplying a bulb
with a nominal current of 0-8amp, is
shown in Fig.
• The normal working shift is about 8 hours,
so that it will be seen that such a battery
has an ample margin of capacity
38
39. • Battery covers are secured in a relatively
permanent manner, usually by special
shrouded screws with wax seals, since it is
necessary to remove such covers only
every 3-6 months. for maintenace.
39
40. Alkaline Batteries for Cap Lamps.
• The alkaline batteries used in cap-lamps to-day
are
usually of the 3-cell type.
• Two makes of cap lamp incorporate 4-cell
batteries, but they are not widely used.
• The cells are of the nickel-cadmium and nickel-
iron types, the groups and electrolyte being
carried in steel containers sheathed in rubber
sacks.
• The three cells are connected in series and
housed in an outer steel container.
40
41. • The plates may be of the pencil type, in which the active material is
carried in a number of pencil-like tubes,
• or flat, with strip pockets to contain the active material.
• A typical discharge curve for an alkaline cap-lamp battery is
shown in Fig.
• The load applied is the normal current of the appropriate bulb,
namely lamp.
• Again it will be seen that the discharge period can be considerably
longer than a normal working shift of some 8 hours.
• The battery cover houses the contacts, a fuse, a cable lock, the
gassing vents and filler holes.
The gassing vents are normally closed during discharge, so that the
cover, usually secured with a magnetic lock, must be removed for
charging
41
42. Charging of Lead-Acid Batteries for
Cap Lamps.
• Lead-acid cap-lamp batteries are invariably charged in
parallel on a modified constant-voltage system, the low-
voltage d.c.power necessary (at about 5-6 volts) being
obtained from a transformer-rectifier unit.
• Adjustment of the output voltage to suit variations in
mains voltage or load current is achieved by tappings
on the transformer primary.
• The voltage applied to the batteries with this system of
charging is critical to about ±100mV; any larger variation
may cause an excessive total charge with consequent
shorter battery life,
• or may result in the battery not receiving a complete
charge.
42
43. • The taper charge, which is controlled by the
balance between the frame voltage and the
battery e.m.f., should be such that when the
battery is fully charged a small residual current
flows into the battery.
• Such an arrangement is fundamentally
necessary for a full self-service lamproom
system.
• Various methods have been adopted to connect
the lamps to the charging circuit, all of which
must allow the lamps to be perfectly safe against
open sparking in normal usage.
43
44. • The first is a mechanical switching arrangement
with one live contact on the exterior of the
headpiece and the other obscured by a lock
barrel which is turned by a live key on the
charging frame to form the negative feed to the
battery.
• A second mechanical device operates on the
principle of a telephone jack-plug; the socket
arrangement offers obscured contacts on the
battery cover and the plug is on the charging
frame.
44
45. • A further arrangement for charging has two contacts on
the
exterior of the lamp.
• One of these is always live and the other is connected to
the battery through a small metal rectifier, which allows
the charging current to flow into the battery but blocks
any return flow which might be dangerous.
• In one make of lamp the rectifier is housed behind the
reflector in the headpiece, and serves also to convert the
single-phase power into the d.c. power necessary for
charging.
• Another make has the rectifier housed under the battery
cover
45
46. Charging Alkaline Cap-Lamp
Batteries
• Charging of alkaline cap-lamp batteries is by constant
current,
• Numbers of the batteries being connected in series.
• The charging current is prescribed by the manufacturers,
and the period of charge is related to the number of
hours which the lamp has been in use.
• The charging stands are so arranged that they can be
fed with direct current, which may be at 110 volts
or 220 volts.
In older installations, the direct-current supply is
• obtained from motor-generator sets, but in modern
plants mercury-arc rectifiers are used.
46
47. LAMP ROOM
• The l.v. constant-voltage charging employed with lead-acid
batteries permits the use of the 'self-service' system
of lamp-room organization, in which the user himself puts his
lamp on charge and removes it from the rack again when
proceeding to work.
• A typical layout for a lamp-room of this type is shown in Fig..
• The route followed by the men is indicated, and it will be noted that
provision is made for a one-way-traffic system, which is advisable to
avoid congestion when large numbers of men have to pass through
the lamp-room at the same time.
47
48. The advantages of the self-service
system
(a ) The lamps require a minimum amount of handling, which
results in a saving in labour and in less damage to equipment,
particularly to bulbs.
The lamp-room personnel are able to devote themselves to the
important operations necessary to maintain a high safety and
lighting standard.
(b) `The men do not have to queue, which results in more orderly
conduct at change of shift times.
(c) Each man has his own lamp and puts it on charge; he thus
takes a greater interest in it, which results in better
maintenance and less damage.
(d) The size of lamp-room required for self-service is less than for
hand issue 48
49. Lamp rooms for alkaline batteries
• A modified form of self-service sometimes termed 'self-help'
is used in some lamp-rooms with lamps having alkaline batteries.
• In this system the men enter the lamp-room and place their
lamps in convenient storage racks from which the attendants
remove the lamps or batteries for charging, replacing them before
they are required for use again.
• Such a system differs from the self-service scheme for cap lamps
with lead-acid batteries, because, in general, alkaline batteries are
not charged at constant voltage and the lamps must be opened
before the batteries can be put on charge.
• A typical self-help layout is shown in Fig. 5.
49
50. Maintenance of Miners' Lamps
• Serviceability is influenced by design factors, but
good maintenance
• basically depends upon the ability and keenness
of the
• personnel in the lamp-room. Obviously, training
can play a
• predominant part here, and it is pleasing to note
that instructional
• courses for lamp-room employees are being
arranged in many
• parts of the country.
50
51. Relative Performance of Miners'
Lamps
• Through the attention devoted to the design of
batteries, bulbs and switch contacts and to
reflector finish, etc., the performance of miners'
cap-lamps has steadily.
• The best method of assessing the efficiency of a
cap lamp as a light-producing medium is to
consider its light-output/weight ratio,
• i.e. the ratio of the light output from the lamp at
the end of a shift to the weight of the complete
lamp
51
52. DISCHARGE CURVES
Discharge curves of a sulphated battery.
a) initial discharge curve.
b) after a reconditioning charge.
c) after a second reconditioning cha
52