This document discusses mercury removal from natural gas streams. It notes that mercury is naturally present in gas reservoirs and must be removed to protect health, the environment, and equipment. Non-regenerative adsorbents using sulfur are commonly used, but activated carbons can have issues with wet gas streams. Newer mercury removal solutions use engineered alumina-based adsorbents with metal sulfide active phases, which have higher mechanical strength and can handle high pressures and water-saturated gas. The document provides examples of using these solutions and compares their performance to other technologies at upstream locations.
Presentation at the 9th WORLD AQUA CONGRESS on 26th-27th Nov 15PRABHASH GOKARN
Tata Steel operates chromite mines at the Sukinda Valley in Odisha producing chrome ore which is subsequently converted it to Ferro Chrome and sold to customers across the world. A large quantity of water, pumped out from the mining pit and due to rainfall, needs to be handled during the mining operations. Chrome Ore mainly contains tri-valent Chromic oxide and a very small fraction of hexavalent di-chromate. Water coming in contact with chromium ore preferentially leaches out soluble hexavalent chromium from the ore body, as a result, water from the mine contains 0.2 – 4 mg/l of hexavalent chromium against a safe limit of 0.005 mg/l for human consumption; requiring all water to be treated before its release from the mines. Thus, Tata Steel is setting up an additional state of art effluent treatment plant at Sukinda with a capacity of 108 million litres/day; one of the largest in the region; which will be completed by Sept 2015. This paper discusses how the technology for the Effluent Treatment Plant was chosen amongst various alternatives, how the capacity of the plant was decided, the challenges during construction of the said Effluent Treatment Plant that were faced, and how these were successfully tackled. The paper also describes how, because the outlet water is of a better quality than the water from the local water body, the outlet water will be used as the input to the Water Treatment Plant, aiding water consumption and lowering operating cost.
Presentation at the 9th WORLD AQUA CONGRESS on 26th-27th Nov 15PRABHASH GOKARN
Tata Steel operates chromite mines at the Sukinda Valley in Odisha producing chrome ore which is subsequently converted it to Ferro Chrome and sold to customers across the world. A large quantity of water, pumped out from the mining pit and due to rainfall, needs to be handled during the mining operations. Chrome Ore mainly contains tri-valent Chromic oxide and a very small fraction of hexavalent di-chromate. Water coming in contact with chromium ore preferentially leaches out soluble hexavalent chromium from the ore body, as a result, water from the mine contains 0.2 – 4 mg/l of hexavalent chromium against a safe limit of 0.005 mg/l for human consumption; requiring all water to be treated before its release from the mines. Thus, Tata Steel is setting up an additional state of art effluent treatment plant at Sukinda with a capacity of 108 million litres/day; one of the largest in the region; which will be completed by Sept 2015. This paper discusses how the technology for the Effluent Treatment Plant was chosen amongst various alternatives, how the capacity of the plant was decided, the challenges during construction of the said Effluent Treatment Plant that were faced, and how these were successfully tackled. The paper also describes how, because the outlet water is of a better quality than the water from the local water body, the outlet water will be used as the input to the Water Treatment Plant, aiding water consumption and lowering operating cost.
The acidizing is pumping of the acids into the wellbore to remove near well formation damage and other damaging substances, matrix acidizing is applied primarily to remove skin damage that caused by drilling, completion, work over, well killing or injection fluids.
This project is concerned with carbonate reservoirs that exceeded in Kurdistan subsurface formations.
Conduct a case study using real industrial data of Arab-D formation (Ghawar oil field – Saudi Arabia) which has five water wells were treated with 50 gallon of HCl acid The treatment acid was placed with coiled tubing and foam was used as diverter. The foam was made from nitrogen, water and surfactants.
Water injection pressure, injection rate and injection flow meter profiles prior to and after the treatment for the five wells show optimistic results to an acceptable extent
In coiled tubing acid placement, the coiled tubing/borehole annulus is usually filled with acid which allow the acid to be in contact with the entire zone at bottom hole temperature condition. This reduces the degree of diversion effectiveness.
Recommend people who work in carbonate reservoirs they should done their work on petrophysical analysis and the porosity should not have exceeded by the acids
Water pollution is one of the environmental challenges facing the world society. Consequently, the pollutants both domestic and industrial wastewater are identified as an environmental threat. Hydrochar (HC) appears as a cost-effective and eco-friendly solution to this environmental threat. HC is the solid produced from the wet pyrolysis process for biomass that is rich in carbon in a sub-critical liquid phase, called the Hydro-Thermal Carbonization Process (HTC). This review aims to address the possibility of using HC as the most effective solution to the industrial wastewater. HTC has proven a greater yield than dry pyrolysis (30%-60% wt). To date, HC is listed as a promising lower-cost alternate adsorbent for removing wastewater pollutants. In Egypt for example, only few studies have been published investigating the properties of HC and its environmental applications. In this review, we will shed light on the preparation, characterization, and previous studies on the development and recent applications of HC. In addition, we will discuss the challenges to produce HC at a commercial scale. To the best of our knowledge, there is only few research studies addressing the HC production in the Middle East countries. Therefore, the door is still opened for more research on developing production techniques on HC from different biomass, and implementation in various environmental applications
This is a modern STP plant at Nashik Maharashtra. This introductory presentation is meant for medical and other students, organised by PSM/ComMed depts.
Operation & maintenance aspects of a Water treatment plant.Home
Operation and maintenance of a treatment plant is task. This is done to expand the life time of the treatment plant. So its necessary to keep the water treatment plant with a good look after on the hand of operation and also in maintenance both simultaneously. The given slides show some operation and maintenance processes to carry out a water treatment plant.
Flue gas desulfurization is commonly known as FGD and is the technology used for removing sulfur dioxide (SO2) from the exhaust combustion flue gases of power plants that burn coal or oil to produce steam for the turbines that drive their electricity generators.
The acidizing is pumping of the acids into the wellbore to remove near well formation damage and other damaging substances, matrix acidizing is applied primarily to remove skin damage that caused by drilling, completion, work over, well killing or injection fluids.
This project is concerned with carbonate reservoirs that exceeded in Kurdistan subsurface formations.
Conduct a case study using real industrial data of Arab-D formation (Ghawar oil field – Saudi Arabia) which has five water wells were treated with 50 gallon of HCl acid The treatment acid was placed with coiled tubing and foam was used as diverter. The foam was made from nitrogen, water and surfactants.
Water injection pressure, injection rate and injection flow meter profiles prior to and after the treatment for the five wells show optimistic results to an acceptable extent
In coiled tubing acid placement, the coiled tubing/borehole annulus is usually filled with acid which allow the acid to be in contact with the entire zone at bottom hole temperature condition. This reduces the degree of diversion effectiveness.
Recommend people who work in carbonate reservoirs they should done their work on petrophysical analysis and the porosity should not have exceeded by the acids
Water pollution is one of the environmental challenges facing the world society. Consequently, the pollutants both domestic and industrial wastewater are identified as an environmental threat. Hydrochar (HC) appears as a cost-effective and eco-friendly solution to this environmental threat. HC is the solid produced from the wet pyrolysis process for biomass that is rich in carbon in a sub-critical liquid phase, called the Hydro-Thermal Carbonization Process (HTC). This review aims to address the possibility of using HC as the most effective solution to the industrial wastewater. HTC has proven a greater yield than dry pyrolysis (30%-60% wt). To date, HC is listed as a promising lower-cost alternate adsorbent for removing wastewater pollutants. In Egypt for example, only few studies have been published investigating the properties of HC and its environmental applications. In this review, we will shed light on the preparation, characterization, and previous studies on the development and recent applications of HC. In addition, we will discuss the challenges to produce HC at a commercial scale. To the best of our knowledge, there is only few research studies addressing the HC production in the Middle East countries. Therefore, the door is still opened for more research on developing production techniques on HC from different biomass, and implementation in various environmental applications
This is a modern STP plant at Nashik Maharashtra. This introductory presentation is meant for medical and other students, organised by PSM/ComMed depts.
Operation & maintenance aspects of a Water treatment plant.Home
Operation and maintenance of a treatment plant is task. This is done to expand the life time of the treatment plant. So its necessary to keep the water treatment plant with a good look after on the hand of operation and also in maintenance both simultaneously. The given slides show some operation and maintenance processes to carry out a water treatment plant.
Flue gas desulfurization is commonly known as FGD and is the technology used for removing sulfur dioxide (SO2) from the exhaust combustion flue gases of power plants that burn coal or oil to produce steam for the turbines that drive their electricity generators.
The explosion hazard in urea process (1)Prem Baboo
In Urea plant passivation air is used in reactor, stripper and downstream of the all equipments. The reactor liner material used Titanium, Zirconium, SS 316L (urea grade), 2RE-69 and duplex material .except Titanium and Zirconium all stainless steel required more passivation air. In CO2 some quantity of Hydrogen is present about 0.14% to 0.2% . The passivation oxygen and Hydrogen makes explosive mixture. To avoid a fire or explosion in a process vessel is to introduce inert (noncombustible) gases in such a way that there is never a mixture with a combustible concentration in exit of MP vent. Mixtures of fuel, oxygen, and inert gases are not combustible over the entire range of composition. In CO2 stripping process the HP scrubber is the risky vessel and this vessel consisting blanketing sphere, Heat exchanger part and a scrubbing part. With help of triangular diagram that shows the shape of the combustible/noncombustible regions for a typical gaseous mixture of fuel, oxygen, and inert at specified temperature and pressure. Present article how to avoid that combustible rang and how to tackle that gases in CO2 & ammonia stripping process.
The role of material in fertilizers industries with energy savingPremBaboo4
In Fertilizers industries the material plays a very important role. Right material can save energy as well as plant life and wrong selection of material may lead to catastrophic failures and outage of plants & even loss of Human lives, Right selection of material leads to long life of plant. In urea plant very corrosive chemicals are used for urea production. The raw material of urea plant is Ammonia and Carbon Dioxide gas which makes very corrosive chemical ammonium Carbamate. For reduced corrosion passivation air is used in reactor as well as stripper according to material of selection different quaintly of air is used. Controlled and less quantity of passivation air is required for Titanium and Zirconium material and hence saving of energy because the huge amount of ammonia is waste with venting of inerts, i.e. saving of energy and environments also. Passivation oxygen given in CO2 is directly proportional to ammonia losses in MP section. This paper intended how to increase life of urea reactor liner and energy saving with low passivation air and high N/C ratio, Ammonia is the noncorrosive and ammonia to CO2 Ratio is an important parameter for process optimization occurring less losses and less explosion probability in urea reactor because it affects the amount of produced urea and corrosion to the material in the reactor. Generally we are using urea reactor liner 316L (urea grade), now adopted 2RE69 for large capacity plant (world largest) and Duplex stainless steel.
Study of the Sulfur Trioxide Generation Mechanism and Control Method Using We...inventionjournals
In coal fired power plant, especially using sulfur content fossil fuels, much attention in recently paid to sulfur trioxide and sulfuric acid mist emission, because conventional desulfurization system should not be removed, which is installed to meet air quality standard for sulfur dioxide. Sulfur trioxide is highly reactive with water vapor and generally convert to sulfuric acid mist in atmosphere. Sulfuric acid is very fine under-submicron sized particulate matter or droplets. Recently sulfur trioxide cause air pollution and public health, discussion comes out, especially in the United States and Japan, that regulations and guideline should be enlarge the sulfur dioxide to sulfur trioxide and sulfuric acid. Moreover most countries reinforce sulfur oxides emission regulations or guidelines from coal-fired power plant. In this study, focusing that how to control the sulfur trioxide and sulfuric acid mist. Sulfuric acid mist found depending on the flue gas temperature. Generation and conversion rate of sulfur trioxide were measured according to temperature. The absorbent was selected to remove sulfur trioxide and sulfuric acid using wet type desulfurization system which the most proven technology at this moment.
The Role of Material in Fertilizers IndustrieswithEnergy saving.pdfPremBaboo4
In Fertilizers industries the material plays a
very important role. Right material can save
energy as well as plant life and wrong
selection of material may lead to
catastrophic failures and outage of plants &
even loss of Human lives, Right selection of
material leads to long life of plant. In urea
plant very corrosive chemicals are used for
urea production. The raw material of urea
plant is Ammonia and Carbon Dioxide gas
which makes very corrosive chemical
ammonium Carbamate. For reduced
corrosion passivation air is used in reactor as
well as stripper according to material of
selection different quaintly of air is used.
Controlled and less quantity of passivation
air is required for Titanium and Zirconium
material and hence saving of energy because
the huge amount of ammonia is waste with
venting of inerts, i.e. saving of energy and
environments also. Passivation oxygen
given in CO2 is directly proportional to
ammonia losses in MP section. This paper
intended how to increase life of urea reactor
liner and energy saving with low passivation
air and high N/C ratio, Ammonia is the
noncorrosive and ammonia to CO2 Ratio is
an important parameter for process optimization occurring less losses and less
explosion probability in urea reactor because
it affects the amount of produced urea and
corrosion to the material in the reactor.
Generally we are using urea reactor liner
316L (urea grade), now adopted 2RE69 for
large capacity plant (world largest) and
Duplex stainless steel.
REVIEW PAPER ON BAUXITE RESIDUE CHARACTERISTICS, DISPOSAL &UTILIZATIONijiert bestjournal
Worldwide bauxite residue disposal areas contain an estimated 2.7 billion tonnes of residue,
increasing by approximately 120 million tonnes per annum. Presently, it is stored on land or in
ocean near alumina refineries. However, its high alkalinity is a potential pollution to water; land
and air of close proximity .meanwhile high cost are associated with a large area of land needed
for storage of residue. In this paper focuses on process of waste generation, its characteristics,
conventional disposal method & bauxite residue utilization in building material glass ceramics,
concrete, bricks, phosphate removal etc.
REMOVAL OF CADMIUM CD (II) AND SILVER AG (I) FROM AQUEOUS SOLUTIONS BY NANO A...IAEME Publication
The extent of removal of heavy metal ions (cadmium and silver) in single and binary system by adsorption on alumina has been investigated. Adsorption experiments were performed in continues flow technique (fixed bed) from synthetic solutions using alumina as adsorbent. Several experimental parameters that affect the extent of adsorption of the metal ions of interest have been investigated such as adsorbent bed depth and concentration of the adsorbate with different contact time. The percent of removal efficiency was also been studied. pH of the system used equal =6.5, temperature =25ºC. This work proposes a cost-effective method for the efficient removal of Cd (II) and Ag (I) from aqueous solutions.
Discussion on Urea Product Quality by Prem Baboo.pdfPremBaboo4
Dear friends today we will discuss on urea product quality. What are the factors on which urea product quality depends? How to improve urea product quality. Urea produced by prilling and granulation rout. In India Prilling is very popular and other countries Granulation rout is adopted. There are some merits and demerits are prilling and granulation routs. Different types of question with their answers
Experience of material in fertilizers industriesPrem Baboo
Materials plays very important role in any industry. Selection of material is vital at design stage itself ,Wrong selection of material may lead to catastrophic failures and outage of plants & even loss of Human lives, Right selection of material leads to long life of plant. In the latest plants specialty 2 RE-69 materials are used for liner. The actual reactor has been constructed using a variety of materials, e.g. Zirconium, Vessel inside a protective liner. This paper intended study Material in urea plant in different vessels and equipment design. In Primary reformer numbers of materials are modified such as micro alloy are also used in tubes.
Waterman Engineers Australia offers scrubbers for controlling air pollution, which are used in industrial operations to remove dangerous pollutants such as sulfur dioxide, nitrogen oxides, and particulate matter from exhaust gases before releasing them into the atmosphere. The most common types of scrubbers are wet scrubbers, dry scrubbers, and electrostatic precipitators. Flue gas desulfurization (FGD) scrubbers are wet scrubbers used to remove sulfur dioxide from industrial and power plant flue gases. Packed tower gas scrubbers and packaged scrubbers are also effective at removing a wide range of pollutants. However, scrubbers produce trash that requires proper disposal and require energy to operate. Using scrubbers in conjunction with other strategies like pollution prevention and source reduction can help reduce emissions to the minimum.
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
Contact with Dawood Bhai Just call on +92322-6382012 and we'll help you. We'll solve all your problems within 12 to 24 hours and with 101% guarantee and with astrology systematic. If you want to take any personal or professional advice then also you can call us on +92322-6382012 , ONLINE LOVE PROBLEM & Other all types of Daily Life Problem's.Then CALL or WHATSAPP us on +92322-6382012 and Get all these problems solutions here by Amil Baba DAWOOD BANGALI
#vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore#blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #blackmagicforlove #blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #Amilbabainuk #amilbabainspain #amilbabaindubai #Amilbabainnorway #amilbabainkrachi #amilbabainlahore #amilbabaingujranwalan #amilbabainislamabad
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
Water billing management system project report.pdfKamal Acharya
Our project entitled “Water Billing Management System” aims is to generate Water bill with all the charges and penalty. Manual system that is employed is extremely laborious and quite inadequate. It only makes the process more difficult and hard.
The aim of our project is to develop a system that is meant to partially computerize the work performed in the Water Board like generating monthly Water bill, record of consuming unit of water, store record of the customer and previous unpaid record.
We used HTML/PHP as front end and MYSQL as back end for developing our project. HTML is primarily a visual design environment. We can create a android application by designing the form and that make up the user interface. Adding android application code to the form and the objects such as buttons and text boxes on them and adding any required support code in additional modular.
MySQL is free open source database that facilitates the effective management of the databases by connecting them to the software. It is a stable ,reliable and the powerful solution with the advanced features and advantages which are as follows: Data Security.MySQL is free open source database that facilitates the effective management of the databases by connecting them to the software.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
We have compiled the most important slides from each speaker's presentation. This year’s compilation, available for free, captures the key insights and contributions shared during the DfMAy 2024 conference.
Harnessing WebAssembly for Real-time Stateless Streaming PipelinesChristina Lin
Traditionally, dealing with real-time data pipelines has involved significant overhead, even for straightforward tasks like data transformation or masking. However, in this talk, we’ll venture into the dynamic realm of WebAssembly (WASM) and discover how it can revolutionize the creation of stateless streaming pipelines within a Kafka (Redpanda) broker. These pipelines are adept at managing low-latency, high-data-volume scenarios.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
RAT: Retrieval Augmented Thoughts Elicit Context-Aware Reasoning in Long-Hori...
Spe 171881-ms
1. SPE-171881-MS
Mercury Removal Units Operation at Front-end Location
Clotilde JUBIN, and Olivier DUCREUX, Axens
Copyright 2014, Society of Petroleum Engineers
This paper was prepared for presentation at the Abu Dhabi International Petroleum Exhibition and Conference held in Abu Dhabi, UAE, 10–13 November 2014.
This paper was selected for presentation by an SPE program committee following review of information contained in an abstract submitted by the author(s). Contents
of the paper have not been reviewed by the Society of Petroleum Engineers and are subject to correction by the author(s). The material does not necessarily reflect
any position of the Society of Petroleum Engineers, its officers, or members. Electronic reproduction, distribution, or storage of any part of this paper without the written
consent of the Society of Petroleum Engineers is prohibited. Permission to reproduce in print is restricted to an abstract of not more than 300 words; illustrations may
not be copied. The abstract must contain conspicuous acknowledgment of SPE copyright.
Abstract
Mercury is present as elemental mercury in natural gas reservoirs and has to be removed in the natural gas
processing plants to protect health, environment and equipment. The mercury removal options are mainly
non-regenerative products. The adsorption mechanism is a chemical reaction between mercury and the
sulfur of the active phase to form non-hazardous and very stable cinnabar phase.
The trend is to implement mercury removal vessels the closest to the production wells to minimize
mercury contaminations in natural gas plants. This up-front location implies adsorbents able to remove
mercury from high operating pressure water saturated natural gas. Metal sulphide active phase adsorbents
have been developed for this purpose.
This paper will present examples of commercial application with existing mercury removal solutions
to illustrate the benefits available from use of the new technology focused on engineered alumina based
products. A case study based on performances comparison with different solutions at up-front locations
will be presented.
Reason of Mercury Removal
Mercury (Hg) is a natural contaminant found in earth’s crust where its concentration can range from 10
to 20 000 ppb. Mercury is thus released into the environment from a variety of natural sources, including
volcanic, geothermal activities or wildfires; but also from anthropogenic activities. A total of approxi-
mately 2000 metric tons of mercury is estimated to be released each year from fossil fuel combustion or
metal production [1]. For instance, natural gas production frequently generates hydrocarbon streams
containing traces level of mercury [2], especially in Southeast of Asia where Hg concentration can reach
up to 300 ppb. Though these levels are rather low, impact on industrial equipment and human health can
be serious [3-4]. For instance, mercury has a strong ability to form amalgams with Al-based alloys used
in LNG (Liquefied Natural Gas) cryogenic exchangers leading to corrosion issues (refer to Figure 1) and
potential industrial disaster like the one encountered in 1973 in Skikda in Algeria [5]. For this reason, a
mercury limit of 10 ng/Nm3
has been established as specification upstream of liquefaction in LNG plants.
In addition, mercury is harmful for human health and numerous incentives have been issued to control
and limit its emission from anthropogenic sources [1]. Suitable personal protective equipment is required
during maintenance work. The European Union Scientific Committee on Occupational Exposure Limits
2. proposes 0.02 mg/m3
as mercury limit in inhaled air
during 8-hours time-weighted average and 0.01
mg/l in blood as biological limit values [6].
Hence, mercury removal is an ongoing issue and
natural gas streams are usually decontaminated us-
ing guard beds protecting downstream equipment.
The mercury is removed in industrial units by
streams circulation through a mercury fixed bed
adsorbent. The main available products on the mar-
ket are non-regenerative products. These guard beds
can be located at different locations in the natural
gas processing chain: either downstream of dryers
or upstream of acid gas removal unit.
Existing Mercury Removal Technologies
The most common approach for mercury removal solutions is non-regenerative adsorbents.
For many years operators have been using the reaction between mercury and elemental Sulfur (S) [6]
to remove mercury from natural gas, downstream of dryers. The sulfur is deposited on a support, typically
carbon, and the resulting captive mass is used in a fixed bed reactor.
The typical mercury adsorption mechanism is a chemical reaction between mercury and sulfur of the
adsorbent active phase, leading to the most stable solid form of mercury called cinnabar (HgS). The
chemical reaction involve is non-reversible and can be depicted here below:
Mercury is chemically bond with sulfur to form mineral cinnabar (HgS) within the porosity of the
adsorbent. Sulfur is either under elemental form (S) or under metal sulphide form (MxSy). Mercury is thus
immobilized in a non-hazardous form and guard beds are designed to decrease traces level of Hg down
to 10 ng/Nm3
. This process is now established as the industry norm.
However, the activated carbons (elemental sulfur deposited on carbons) suffer from many drawbacks
such as possible sulfur loss during mercury removal operation and are prone to capillary condensation for
wet gas [7], in case of location upstream of the drying section. Activated carbon has a very high surface
area and very small pore size (average pore size Ͻ 20 angstrom). This makes it a very effective adsorbent
but also makes it very susceptible to capillary condensation of water and/or C5ϩ compounds. This
restricts access of mercury to the sulphur and increases the length of the Mass Transfer Zone in the vessel.
In addition, the capillary condensation leads to pressure drop issues.
Because of problems with capillary condensation, these beds are located at the final stage of
purification downstream of the molecular sieve dryers even if this location is not the ideal one as only part
of the mercury arriving in the plant is removed (mercury is also released into the acid gas, the regeneration
gas and the condensed water). Furthermore a pressure drop is introduced into the final stages of
processing. Thus, sulfur impregnated carbon can only be used on dry gas.
Axens was pioneer in the development of an alumina-based adsorbent for mercury removal with the
launching of first CMG product in early 70’s. Intensive R&D leads to improvement of these adsorbents
now named AxTrap™ 200 Series adsorbents. These adsorbents consist on a finely dispersed active phase
firmly linked to the alumina carrier thanks to a proven manufacturing process.
Other mercury technologies have been launched in the 90’s. These products are called ‘bulk metal
sulphides’. These guard bed adsorbents include a metal sulphide active phase and a binder to make the
shape of the adsorbent. The main drawback of these adsorbents is linked to this binder addition which is
Figure 1—Picture showing the effect of amalgam formation on alumi-
num-based cryogenic heat-exchangers
2 SPE-171881-MS
3. responsible of lack mechanical properties during their operation. Figures 2 compare the both metal
sulphide active phase technologies.
The main benefit of the alumina carrier is its robustness. Alumina carriers offer very high and stable
mechanical resistance and do not generate any dust, even under drastic operating conditions with high
operating pressure and water saturated streams.
Moreover, this technology does not include any binder: there is no risk of fines formation, in case of
free water presence,
In addition, there is no risk of loss of sulfur by sublimation or dissolution. All sulfur species are
securely bound thanks to the metal and this kind of adsorbents can be used also for liquid hydrocarbons
purification.
Some regenerative solutions based on mercury physisorption exist on the market. These adsorbents are
located in the same vessel as the molecular sieve dedicated to the drying. Nevertheless, part of the mercury
can be desorbed during the regeneration step leading to mercury presence in regeneration gas. Conse-
quently, a non-regenerative adsorbent has to be implemented on the regeneration gas. In addition, this
product has to be replaced at the same time as the mole sieve for drying which has generally a shorter life
time than the mercury removal adsorbent itself.
Mercury Removal Challenges
Since the beginning of the 2000’s, the trend is to implement mercury removal vessel the closest as possible
to the production wells in order to avoid mercury accumulation in the process pipes or in the effluents
(acid gas from the acid gas removal unit, dryers regeneration gas, condensed water from dryers
regeneration gas). At this location the natural gas is at its dew point which implies frequent or permanent
liquids entrainments (water and hydrocarbons) in these operating conditions. As a consequence, activated
carbons cannot be used at this location thus it was a necessity to develop high and stable mechanical
resistance products which are able to remove mercury on water saturated streams and at high operating
pressure.
Inorganic routes including a metal sulphide as active phase have been investigated to ensure active
phase stability in such operation. In addition, metal sulphide based on alumina presents a very high
mechanical resistance in particular in case of water presence.
One way to avoid operating problems is to optimize the interaction between the alumina carrier and the
active phase deposited within the solid. For instance, pore size distribution can be tuned to avoid capillary
condensation issues and the nature of the active phase and mineral support can be adequately chosen to
obtain strongly bound and finely dispersed mercury-reactive nanoparticles.
As enounced, the mercury adsorption reaction on a metal sulphide can be depicted with:
Figure 2—Mercury Removal Technologies with a metal sulphide active phase a) ‘bulk technology’ and b) ‘supported technology’
SPE-171881-MS 3
4. The limitation factor of this mechanism is neither the thermodynamic nor the reaction kinetic but the
mercury diffusion. There are different diffusion types: diffusion of mercury to the adsorbent external
surface, diffusion of the mercury through the gas film around the adsorbent particle and the mercury
diffusion inside the adsorbent particle as depicted on Figure 3.
The adsorbent particle shape and size can be both tuned to enhance the mercury external diffusion. The
alumina carrier porosity can be tailored to optimize the mercury adsorption efficiency, avoiding capillary
condensation in gas phase and enhancing the access for the mercury to the active sites as modelled on
Figures 4. The optimization of the alumina carrier porous profile helps the mercury to diffuse all along
the adsorbent bead.
The diffusion of the mercury contained in the gas phase can be impacted by the presence of liquids.
In case of liquid carry-overs, liquids will fill the porosity and block the access of mercury to the active
sites leading to a broadening of the Mass Transfer Zone inside the vessel. The curve b) of Figure 5
represents the mercury diffusion across an optimized adsorbent bed in absence of any liquid whereas the
curve a) represents the same but in case of some liquid carry-overs. The saturation capacity of the product
is remaining the same but because of diffusion issues, the mercury breakthrough will occur before the
expected life time in case of liquids carry-overs (curve a) of Figure 5). This highlights the crucial impact
of diffusion on mercury removal performances and shows that a short life time can be observed even with
a capacitive adsorbent.
Figure 3—Different kinds of mercury diffusion to active sites
Figure 4—Mercury trapping modelling a) over a standard adsorbent and b) in AxTrap™
200 Series optimized bead
4 SPE-171881-MS
5. Results of a Case Study on Water Saturated Gas Stream
A documented Industrial fixed bed column case study will be presented during the conference to show the
differences between the two existing metal sulphide technologies and to explain why alumina supported
based adsorbents is the suitable technology for mercury removal at up-front location.
The chosen case concerns a natural gas Floating, Production Storage and Offloading (FPSO) in South
East Asia Area, but other similar examples happened elsewhere, in both offshore and onshore plants where
the MRU is located upstream of the molecular sieves dryers. In this present case, MRU is located
downstream of a coalesce without any superheater.
Mercury Removal Performances with ‘bulk metal sulphides’
The end-user of the project chose first the ‘bulk metal sulphide technology’ with the proposed adsorber’s
design.
The unit has been designed to handle feed flowrate: 450 MMSCFD, mercury inlet concentration: 500
g/Nm3
, operating temperature: 30°C and operating pressure: 50 bar a.
Since the beginning of the first adsorbent’s load, the mercury outlet specification was not met. Indeed,
the mercury outlet concentration was higher than 1 g/Nm3
after only 2 weeks in operation. In addition,
the operators faced pressure drop issues after only 80 days in operation (pressure drop higher than 1 bar).
Fifteen batches of different ‘bulk metal sulphides’ were tested and same results were obtained. It appeared
that on water saturated natural gas stream, under high pressure (50 bar), frequent free water and/or liquid
entrainment occurred, even if a coalescer is installed. The lack of mercury removal performances and the
high observed pressure drop have been explained by the ‘bulk metal sulphides’ weakness. In case of free
water upsets, the destruction of the link between the binder and the active phase is possible. Accumulation
of fines on the bed was observed and cementation of the product occurred. The adsorbent unloading
operation was very difficult to perform as a jackhammer was required.
Mercury Removal Performances with ‘supported metal sulphides’
Axens adsorbents were loaded in the mercury removal vessel for the first time in October 2011.
For this first load, a high capacitive AxTrap 271 adsorbent was proposed. This product is under beads
shape with a 3 mm average diameter.
The pressure drop was lower than 1 bar specification and was very stable without any fines generation.
The 1 g/Nm3
mercury outlet specification was achieved during 20 days. This has been depicted on
Figure 6.
Figure 5—Mercury diffusion profiles a) in case of liquid carry over and b) without liquid carry-over
SPE-171881-MS 5
6. The observed performances were improved as the life time was a little bit increased and the pressure
drop met the specification (pressure drop was ca. 0.3 bar). Nevertheless, the mercury removal perfor-
mances were lower than expected and this lack of performances was attributed to some liquid carry-overs.
Spent product samples were easily unloaded and the analyzed revealed clearly that only a small part
of the active sites have been used.
Axens studied the way to increase the adsorbent lifetime with improving the mercury access to the
active sites. This was possible thanks to 1) modelling tools developed from industrial experience and pilot
tests and 2) different types of tailored alumina based adsorbents. The investigated ways to improve the
diffusion of mercury to active sites is to favour both external and internal diffusions of mercury as
described on Figure 3.
As a consequence, Axens decided to select AxTrap 273, an adsorbent with a smaller particle size and
with a higher porous volume in order to improve respectively the extra particles and the intra particles
diffusion.
Figure 7 represents the porous distribution of two AxTrap 271 and AxTrap 273 adsorbents. Both
adsorbents have an opened porosity without any pores lower than 10 nm (no microporosity). The total
porous volume of AxTrap 273 is higher than the one of AxTrap 271. This is due to:
1. The presence of smallest pores in case of AxTrap 273. AxTrap 273 smallest pores median diameter
is in the 10 nm range whereas AxTrap 271 smallest pores median diameter is in the range of 30
nm median diameter; and
2. The presence of macropores in case of AxTrap 273 (median diameter higher than 100 nm).
Finally, AxTrap 273 has a higher total porous volume than AxTrap 271 and presents a bimodal porous
distribution (mesopores and macropores) while AxTrap 271 has only a monomodal porous distribution
(mesopores). Furthermore, due to a higher total porous volume, AxTrap 273 is less dense than AxTrap
271.
At the same time, the way to improve extra particle diffusion was studied. It is important to highlight
that the proposed AxTrapTM
products were very stable and generated a low pressure drop in operation (ca.
Figure 6—Mercury removal performances with AxTrap 271
6 SPE-171881-MS
7. 0.3 bar with 3 mm average diameter beads). As a consequence, some pressure drop margins existed and
the replacement with AxTrap 273 in small beads has been investigated.
Thanks to our modeling tools, the predicted performances have been simulated with the real operating
conditions (see Figure 8). The results of these simulations shows a sharper mass transfer zone (between
1 and 2.5 meters of the bed’s height), associated with a longer saturation zone (between 0 and 1 meter)
and thus, a better use of the mercury removal bed with AxTrap 273. Loading of AxTrap 273 1.4-2.8 mm
adsorbent seemed to be a very good way to improve the mercury removal performances of the unit, to
optimize the dynamic adsorption capacity.
Figure 7—Comparison of Porous Distributions of AxTrap 271 and AxTrap 273
Figure 8—Modeling of mercury adsorption profiles versus bed height with a) AxTrap 271 and b) AxTrap 273 small beads
SPE-171881-MS 7
8. Finally, AxTrap 273 1.4-2.8 mm was loaded in the unit and the life time was very significantly
increased: the mercury outlet concentration was on specification during more than 160 days (Figure 9)
instead of 20 days with AxTrap 271 (Figure 6).
This product has been replaced many times and the better run reached 220 days in operation (Refer to
Figure 10) after minimizing the liquid’s upsets. This shows that the mercury removal performances
prediction can be difficult to foresee, due to the difficulty to know the real amount of liquids presents
upstream of the Mercury Removal Units in a “front-end” configuration. Nevertheless, the mercury
removal performances have been notably enhanced, after the simulation study with AxTrap 273 solution.
Figure 9—Improvement of mercury removal performances with AxTrap 273
Figure 10—Improvement of mercury removal performances with AxTrap 273 small beads
8 SPE-171881-MS
9. The observed pressure drop versus feed flow rate diagram is presented on Figure 11.
The observed pressure drop has been below the specification and very stable since the first day in
operation, as shown on Figure 12.
Thanks to this very robust adsorbent and its diffusion transfer properties optimization, the unit
performances have been highly increased fom 14 days with ‘bulk metal sulphides’ technology to 220 days
with ‘alumina supported metal sulphides’ technology. In addition, the pressure drop issues have been
solved.
Figure 11—Monitored pressure drop versus feed flowrate with AxTrap 273 small beads
Figure 12—Flowrate normalised pressure drop with AxTrap 273 small beads
SPE-171881-MS 9
10. Conclusion
The mercury removal vessels are now located in a “front-end” location in the natural gas treatment chain
in order to minimize mercury contamination along the natural gas processing chain. As a consequence,
operating conditions are more drastic with higher operating pressure and water over-saturated streams.
Thus, very stable and liquid resistant adsorbents are required. Furthermore, presence of free water leads
to diffusion issues with a broadening mass transfer zone and therefore a premature mercury breakthrough.
In these conditions, Alumina supported metal sulphides allow to radically improve mercury removal
performances compared to other technologies thanks to 1) the higher mechanical resistance and 2) both
tailored adsorbent particle and porosity. The external and the internal diffusion of mercury to active sites
diffusion can be improved with respectively, an optimized particle size and can be made easier with an
opened porosity. Pore size distribution has to be tuned to avoid capillary condensation issues.
This kind of adsorbents is very robust due to the alumina carrier, a very well-known product for drying
application. In addition, the interaction between the carrier and the active phase is optimized, leading to
very stable products.
This paper shows clearly that it is not efficient to have only very capacitive adsorbents in these high
pressure and water saturated conditions. These materials have to be very robust and to be designed such
as to maximize the active sites accessibility for optimizing the mercury dynamic adsorption capacity. In
parallel, the development of very powerful modeling tools help a lot to manage an optimization study and
to improve the performances of mercury removal units.
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