Oil Field Chemicals Chemicals for Production Services

Total Page:16

File Type:pdf, Size:1020Kb

Oil Field Chemicals Chemicals for Production Services Oil Field Chemicals Chemicals for Production Services VIRA BASPAR BARTAR The Chemical and Polymer Company Oil Field Chemicals From production chemicals to drilling chemicals and cementing additives, Vira Baspar Bartar offers the widest product in the oilfield chemical industry, combined with the experience, knowledge and insight to develop quality products and ready-made solutions. We strive to be at the forefront of innovation, with a dedicated team of experts continually introducing new technologies and improving existing products according to the needs of this demanding industry. Chemicals for Production Services Our proven strengths are innovative, sustainable solutions with consistent product quality. Specialty chemicals that impart unique capabilities and functionality are an integral part of our goal.We provides a broad range of high- quality chemicals to help service companies meet their technical challenges in production services. By constantly improving the quality and reliability of our chemical solutions, we help service companies meet the industry’s overall drive for greater efficiency and productivity. Asset Integrity Chemicals Corrosion Inhibitor Biocide H2S Scavenger Multifunctional chemical for hydrotesting Oil / Water Separation Process Chemicals Demulsifier Antifoam Water clarifiers / Deoilers Flow Assurance Chemicals Wax Inhibitor Asphaltene Inhibitor Drag reducing agent Gas hydrate inhibitor Scale inhibitor Asset integrity chemicals A proper plant management is mandatory to reach the life design of the assets. To accomplish the target, it is mandatory to put in place effective measures for risk assessment and control. Our long term experience and know-how allow us to be a trustworthy partner for the development and management of chemical treatments that can be integrated in the asset integrity management strategies to control any kind of corrosion and biofouling, as well as enhance the process and its relevant CAPEX and OPEX. We support our clients in defining the most competitive chemical strategies to the safety and the environment preservation. We supply a range of corrosion Inhibitor, biocide, H2S scavenger and multifunctional chemical for hydrotesting that give our customers the confidence that their assets are protecting. Corrosion Inhibitors Corrosion inhibitors are chemicals that are added to a chemical stream to prevent corrosion, or lower the rate of corrosion so that the processing equipment will have a suitable service lifetime. We produce all types of corrosion inhibitors for the protection of asset in oil and gas production services. Vira Baspar Bartar Co. offers a wide range of innovative corrosion inhibitors for the protection of all types of systems include the following products. 1- Oil/ water soluble corrosion inhibitor for oil field 2- Oil/ water soluble corrosion inhibitor for gas field 3- Gas lift corrosion inhibitor 4- CO2 corrosion inhibitor for sweet oil and gas system 5- Corrosion inhibitors for overhead refineries system Biocide The phenomena of microbiological contamination of the oil and natural gas environment represent a broad issue. The negative effect of microorganisms is primarily associated with the degradation of petroleum hydrocarbons, leading to an increase in oil density, sulfur content and viscosity. These changes cause disruption in oil extraction and processing technology, bringing about significant economic losses. Problems also concern the ways crude oil is stored, products of its processing, drilling fluids, and natural gas. In addition to lowering the content of hydrocarbons in crude oil, adverse activity of micro-organisms causes corrosion of transmission installations (oil and gas pipelines) and the production of undesirable substances (H2S, polymers, organic acids, etc.) that affect the performance of oil and gas. Attempts to eliminate microorganisms involve using chemicals, exhibiting biocidal properties, which besides the physical method is the most popular and most effective technique of eliminating microbiological contamination. Biocide is a chemical substance capable of destroying different forms of living organisms. Some bacteria, like SRB (sulfur reduced bacteria) which forms some algae in crude oil, are harmful for equipments. This will stick on equipment surfaces and reduce performance. Using Biocide helps to get rid of such bacteria and avoid equipment deficiency. The selection of appropriate antibacterial or antifungal agents requires the consideration of factors affecting the efficiency of the process. Vira Baspar Bartar Co. produces a broad spectrum biocide to prevent fouling of bacteria. We recommend the appropriate biocides for use in oil and gas field application. H2S Scavenger The application of sulphide scavengers is a widely adopted practice in production and processing operations in the oil and gas industry. Hydrogen sulfide (H2S) is a very toxic and pungent gas that causes problems in both the upstream and downstream oil and gas industry. The process of removing H2S is known as gas sweetening, by either iron sponge H2S scrubbers (forming iron sulfide) or chemical scavengers. We offer hydrogen sulfide scavengers that can be applied via continuous injection or through batch treatments. The benefits of our product include: Improved safety due to reduced hydrogen sulfide content; Removal of H2S gas from process systems, thereby reducing corrosion; and Maintain asset integrity and reduce the need for replacement equipment. 1 3 3 S .6 p m 92.1 H H Multifunctional chemical for hydrotesting Our precisely and cautiously formulated multifunctional chemical for hydrotesting is commandingly suitable for inhibiting the corrosion from the interior metal surfaces. We make use of finest quality ingredients and chemical compositions to ensure excellent protection from corrosion. These chemicals are highly effective in the amalgamation of oxygen scavengers and biocides. Our formulations effectively prevent pipelines and equipments from corrosion where sea water or sweet water is being utilized. The features of our offered inhibitors are highly miscible in water, accurate composition, precise pH value, excellent corrosion prevention and biodegradable. The multifunctional chemical for hydrotesting is utilized for preventing pipelines, equipments, valves and various other hydrostatic instruments from corrosion. Oil /Water Separation Process Chemicals Oil /water separation by the different gravity of the two phases is a very slow process, but can be accelerated by the assistance of chemicals. The chemicals used are termed demulsifiers, antifoam and water clarifiers /deoilers. We supply a range of demulsifiers, antifoam and water clarifiers /deoilers that give our customers the confidence that their processes are controlling. Demulsifier Emulsion breaking is one of the most complex and situational aspects of oilfield chemistry. Stable emulsions encountered in oil production are normally composed of varying levels of water or brine dispersed in a continuous oil phase. These emulsions are stabilised by compounds occurring naturally in the crude. The severity of the emulsion formed and thus the ease at which it can be broken is dependent on: 1- Physical and chemical properties of the crude oil, 2-Production temperature, 3- Distance between reservoir and topsides, 4- Degree of agitation experienced between reservoir and separator, turbulent flow presence of solids (sand, clay, bacteria, scale, asphaltenes, corrosion product, napthenates) and / or natural surfactants which act to stabilise the emulsion. Demulsifier or emulsion breakers that separates the water from the "water/crude oil" emulsion. Demulsifier additive chemical breaks the crude oil emulsion into crude oil and water. Demulsifiers are key components of production formulations which enable the quick separation of produced water from oil. Separating crude oil from water can be very time critical due to short residence time. Vira Baspar Bartar Co. create the new demulsifier formulation for demulsification of crude oil emulsion. Demulsifier selection by us is normally carried out in the field by our highly experienced bottle testing engineers. A wide selection of demulsifier chemistries are screened individually and in the form of blends. Antifoam Anti-foaming additive suppresses foam when all types of crude oil tanks are being cleaned. Foaming is a function of crude oil type which either permits small gaseous bubbles to be encased in a thin film of crude oil as the gas comes out of the crude oil solution or permits gaseous bubbles as the viscosity and surface tension of the crude oil changes and mechanically unlocks the gas. Anti-foaming additive avoids operational cost increases due to foam induced crude oil supply disruption. Anti-foaming solutions have employed chemicals, heat, or mechanical processes such as settling, agitation, or centrifugal force. Each process provides solutions, but can also create additional problems necessitating further remediation. Vira Baspar anti-foaming additive employs new chemistry to solve the foaming challenge without creating additional problems necessitating further remediation. Silicone-based Vira Baspar defoamers are polymers with silicon backbones. These might be delivered as an oil or a water based emulsion. These are also heavy duty defoamers and are good at both knocking down surface foam and releasing entrained air. Our defoamers are suitable in non-aqueous foaming systems like crude oil and oil refining. Water clarifiers / Deoilers Tightening
Recommended publications
  • Electronic Water Treatment an Alternative Solution to Removing Beerstone and Limescale
    WATER & WASTEWATER solutions Electronic Water Treatment An alternative solution to removing beerstone and limescale By Jan de Baat Doelman, Scalewatcher North America Inc. eer contains 90 percent water and is the most important ingredient in determining its flavor. Water contains B calcium and is the most important mineral to the brewing process. The levels of calcium in local water have determined the type of beer produced. The different types of beer whether a light lager or a porter are for the most part due to the water profiles of the areas that made the styles famous. Calcium is by far the most influential mineral in the brewing process. It reacts with phosphates, forming precipitates that involve the release of hydrogen ions and in turn lowers the pH of the mash. Calcium is the principal mineral of hardness, an unhygienic surface that can harbor microorganisms. An which increases mash acidity and inverts malt phosphate. It unhygienic surface will infect the beer. Beerstone can cause stimulates enzyme activity and improves protein digestion. “off flavors” or shorten the shelf life of beer. In the worst case Calcium also extracts the fine bittering principles of the hop. scenario, undesirable organisms can ruin an entire batch of However, although calcium is the most important ingredient beer, costing time and money to replace. in brewing beer it also has a negative effect on brewing equipment as it creates beerstone and limescale. LIMESCALE Although calcium is an essential ingredient in beer production BEERSTONE it also creates limescale, which has a negative effect on heat Beerstone is calcium oxalate that appears in mash kegs, exchangers, reverse osmosis (RO), pipes and vessels used boiling kegs, tanks and lines.
    [Show full text]
  • Got Scale? Get the Facts!
    EVERPURE® GOT SCALE? GET THE FACTS! “Scale” is anything and everything include hydroxide scale, silica FACT: Water filters alone do solid that is deposited onto surfaces scale, even phosphate scale, plus not remove scale. Water filters that come into contact with water. ordinary dirt, rust, etc. that settle as with scale inhibitors treat water The most important and common sediment and get incorporated into so that scale does not form in type is limescale, but other types other scale types. water-using equipment. DIFFERENT KINDS OF SCALE Limescale is limestone that is first The changes that cause limescale to dissolved from the ground and then precipitate are: caused to re-form later in water- • pH increase (a pH of 8 is ten times using equipment when the water more scale forming than a pH of 7) chemistry changes. It is mostly calcium carbonate (CaCO3), but in • high temperature many places magnesium carbonate • any increase in concentration of may account for up to 1/3 of the total. hardness, TDS, and/or alkalinity Hydroxide Scale is a fluffy, cloud- like “floc” that forms around ions of certain metals at high pH and then settles into a gooey sludge that sometimes acts like a cement. Examples are iron hydroxide floc and aluminum hydroxide floc. Silica Scale is essentially glass, and it forms wherever soluble silica levels above about 15 ppm encounter a heat transfer surface, such as is found in a coffee brewer. Phosphate Scale occurs only if to ortho- (single) phosphate by polyphosphate treatment is flawed. excessive storage temperature, If the dosage is excessive, calcium ordinary calcium phosphate can polyphosphate may precipitate.
    [Show full text]
  • THE CHEMISTRY of LIMESCALE Limescale Can Clog up Your Kitchen Appliances, and Build up on Your Bathroom Surfaces
    THE CHEMISTRY OF LIMESCALE Limescale can clog up your kitchen appliances, and build up on your bathroom surfaces. What actually causes this build up? Here’s a quick look at the chemistry behind limescale formation, chemicals that can help prevent it, and others that help to remove it. WATER HARDNESS WATER SOFTENERS IN OUT CALCIUM IONS SULFATE IONS Na+ Na+ Na+ Na+ O OH 2+ – O O 2+ + 2+ Na Ca Ca + Ca2+ Ca2+ Na+ Na 2+ Mg 2– HCO3 Ca2+ Na+ HO OH + + + + Ca SO4 Na Na Na Na OH MAGNESIUM IONS BICARBONATE IONS ION EXCHANGE RESIN CITRIC ACID ‘Hard water’ is water which contains a large amount of mineral Appliances such as dishwashers can soften water ions, most commonly calcium and magnesium ions. Permanent by passing it through an ion exchange resin. This hard water is mainly due to dissolved calcium and magnesium exchanges scale-causing metal ions in the water for sulfates. Temporary hard water is mainly due to dissolved calcium bicarbonate. Temporary hardness can be removed by boiling the sodium ions. Compounds such as citric acid and sodium water, but permanent hardness cannot. sesquicarbonate can be used to soften laundry water. LIMESCALE & SOAP SCUM 2+ 2– REMOVING LIMESCALE 2+ – O Ca (aq) + 2HCO3 (aq) CaCO3(s) + CO2(aq) + H2O(l) Ca CO3 O O H N S OH HO P OH Calcium bicarbonate can decompose when heated to form insoluble OH 2 H Cl Limescale consists mainly of calcium calcium carbonate – known in this context as limescale – along OH O OH with water and carbon dioxide.
    [Show full text]
  • Fouling 7 01.Pdf
    LIMESCALE By Jan de Baat Doelman ControllingControlling ScaleScale DepositionDeposition andand IndustrialIndustrial FoulingFouling ook at the heating element of a growth of algae and bacteria (bio-fouling), washing machine or dishwasher the consolidation of loose particles (particu- Lin a hard water area and you will late fouling, [e.g., corrosion by products]) see a white encrustation containing hard- and the accumulation of “coke” like deposits ness salts. This is commonly referred to as (chemical reaction fouling). limescale and is an example of domestic fouling. The limescale (calcium carbonate) What Can Go Wrong? that deposits on the heating element will, if Process managers should be concerned untreated, reduce the efficiency of the about fouling. Deposits are an insulating layer machine, induce corrosion of the element on heat transfer surfaces. These deposits lead and ultimately lead to appliance failure. to more power being consumed or to the Industrial fouling poses a far greater installation of heavier duty, more expensive L Treatment options for limescale build-up include problem than in the domestic sector. This heat exchangers to compensate. It is estimat- inhibitor chemicals, descalers, ion exchange, is because huge volumes of fluids are han- ed that 40 percent more energy is needed to physical cleaning, magnets and electronic devices. dled and the systems that contain the fluids heat water in a system fouled with 0.25″ of can become fouled. The quality of water calcium carbonate scale. Scaled boiler tubes to maintain throughput volumes but this is streams used by industry varies widely and mechanically fail as a result of overheating, only a temporary solution to the problem.
    [Show full text]
  • Water Hardness & Limescale
    Water Hardness & Limescale Corrosion Scale "Slight corrosion of iron promotes the precipitation of calcium carbonate (Lime-scale), 2+ since the Fe ions enable the nucleation of CaCO3 at low super-saturations" E.REVAULT, J.BARON, J.LÃ DION, Influence des ions Fe2+ sur le pouvoir entartrant de l'eau. Lime-scale (Hard water) When rain falls through the atmosphere, it takes into solution a certain amount of carbon dioxide making it slightly acidic. This acidity together with the fact that pure water such as rain water is a good solvent causes substances in the ground such as lime stone and chalk to be dissolved. They react with the acidity of the carbonic acid H2CO3 to form soluble salts. These salts exist in the main as either relatively insoluble carbonates or quite soluble bicarbonates of calcium and magnesium. Carbonates are said to be substances which cause "permanent" hardness and bicarbonates cause "temporary hardness". The latter cause most of the problems associated with hard water since the application of heat causes them to break down according to the following equation causing scale. Calcium Bicarbonate plus heat gives Calcium carbonate plus water plus carbon dioxide. Ca (HCO3)2 + HEAT CaCO3 + H2O + CO2 This reverses the original reaction between carbonic acid and the calcium carbonate. The insoluble calcium carbonate is deposited upon heating surfaces and pipes as a result. In the main, chemical methods have been used to combat the expensive and inconvenient problems, which arise as a result of using hard water. Water softeners which use salt to regenerate special resins, which remove calcium ions from water are now less environmentally acceptable, in some countries they have been banned due to the contamination of ground water which contains large amounts of salt effluent from water softeners.
    [Show full text]
  • Big, Bad Limescale
    Commercial WATER Big, Bad Limescale The detrimental effects of hard water & scale on plumbing & water treatment equipment BY SUSAN WHITE imescale caused by hard water can wreak havoc on any type of appliance, system, pipe or valve that water runs through. Due to drought in various parts of the U.S., hard water is becoming Lmore of a nuisance because of constant changes in the water table and groundwater quality. The challenges facing any business involved with maintaining water distribution systems today are extreme. Yearly maintenance and repair costs to water systems add up to many millions of dollars in certain areas of the U.S., and groundwater is only getting harder. According to the U.S. Geological Survey, pat- terns of hardness vary across the U.S. Water hardness is based on major ion chemistry concen- trations, which are relatively stable in groundwater and generally do not change over time. The softest water is found in parts of New England, the South Atlantic/Gulf states, the Pacific Northwest and Hawaii. Moderately hard water is An extreme example of the effects hard water can have on pipe common in rivers in Alaska and Tennessee, the Great Lakes region and the Pacific Northwest. Hard damage boilers, cooling towers, water heaters and using or exposed to the systems. and very hard water is found in some streams in other water-handling equipment. ASHRAE identifies the conditions in a building’s most of the country. The hardest water was mea- High levels of hard water ions such as Ca2+ water system that make it less likely for Legionella sured in streams in Texas, New Mexico, Kansas, and Mg2+ can cause scaly deposits in plumbing, to grow and spread, and recommends mainte- Arizona and California.
    [Show full text]
  • Health Technical Memorandum 04-01: Safe Water in Healthcare Premises Part a on the NHS Website
    This document has been withdrawn. Find Health technical memorandum 04-01: safe water in healthcare premises part A on the NHS website. Department of Health Health Technical Memorandum 04-01: Safe water in healthcare premises Part A: Design, installation and commissioning withdrawn Health Technical Memorandum 04-01 Safe water in healthcare premises Part A: Design, installation and commissioning withdrawn Health Technical Memorandum 04-01: Safe water in healthcare premises: Part A – Design, installation and commissioning withdrawn © Crown copyright 2016 You may re-use this information (not including logos) free of charge in any format or medium under the terms of the Open Government Licence. To view this licence, visit www.nationalarchives.gov.uk/doc/open-government-licence/ or write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or email: [email protected]. This document is available from our website at https://www.gov.uk/government/collections/health-technical-memorandum-disinfection-and­ sterilization iiii Contents Contents Executive summary ...................................................................................................................iv Acknowledgements ..................................................................................................................vii Glossary and abbreviations ......................................................................................................ix 0 Policy and regulatory overview: water safety and the healthcare estate
    [Show full text]
  • Hard & Soft Water
    HARD & SOFT WATER This factsheet was written for teachers and a general audience as part of the BBC ‘Terrific Scientific’ schools initiative. A factsheet for primary school students aged 9-11 is also available on the website: www.geolsoc.org.uk/waterhardness Image Left: Soap bubbles in soft water Image Right: Limescale crust in a kettle after repeated boiling of hard water (© Henna /Wikimedia) Have you ever noticed that tap water tastes different depending on where you are? Have you ever seen a white coating inside your kettle or the shower head, or Hard water: good or bad? found that the shower gel won’t lather up? All these eff ects are caused by differences in the The good : ‘hardness’ of the water. Some minerals in hard water have health benefits, such as those containing calcium, Hard and soft water – the chemistry (good for bones and teeth). Some people think it tastes better. Hard water is water that contains dissolved minerals (the materials that make up rocks) . Water containing less dissolved minerals is known as soft The bad: water. In the UK, both hard and soft tap water is safe to drink. When some hard water is boiled, the dissolved minerals solidify to form a hard Rainwater is naturally soft, but dissolved carbon dioxide gas from the white coating of limescale. This blocks atmosphere makes it slightly acidic. (This should not be confused with pipes and stops kettles working so well. ‘acid rain’, which is much stronger and is caused by different gases). Hard water forms ‘soap scum’ instead of Rainwater soaks into the ground after it falls and then flows slowly lather when soap is added.
    [Show full text]
  • Controlling Scale Deposition
    EDITOR’S EMPHASIS By Jan de Baat Doelman, Scalewatcher North America, Inc. C&I A commercial & industrial article Industrial Fouling Controlling Scale Deposition ook at the heating element of a overheating and cooling tower plates washing machine or dishwasher can collapse due to the weight of scale L in a hard water area and you deposits. Erosion damage can occur as will see a white encrustation containing a result of scale particles breaking loose hardness salts. This commonly is referred and then subsequently impinging upon to as limescale and is an example of other surfaces. domestic fouling. The limescale (calcium carbonate) that deposits on the heating Pipework scale reduces the available cross- element will, if untreated, reduce the section area, and fluids are affected by efficiency of the machine, induce increased pipewall friction. A larger, more corrosion of the element and ultimately power-consuming pump will be required lead to appliance failure. to maintain throughput volumes but this may allow only a temporary solution to Industrial fouling poses a far greater the problem. Plants that need to be shut problem than anything in the domestic down for cleaning cost money. sector. Huge volumes of fouled fluids are handled, and the systems that The formation of a thin uniform layer contain the fluids can become fouled as of scale or wax temporarily can reduce well. The quality of water streams used steel corrosivity, but eventually stagnant by industry varies widely and gives rise conditions develop under the deposit to numerous fouling problems. and electrochemical reactions will algae and bacteria (biofouling) and the layer on heat transfer surfaces.
    [Show full text]
  • FOOD PROCESSING TECHNOLOGY Principles and Practice
    FOOD PROCESSING TECHNOLOGY Principles and Practice Second Edition P. Fellows Director, Midway Technology and Visiting Fellow in Food Technology at Oxford Brookes University Published by Woodhead Publishing Limited Abington Hall, Abington Cambridge CB1 6AH, England Published in North and South America by CRC Press LLC 2000 Corporate Blvd, NW Boca Raton FL 33431 USA First edition 1988, Ellis Horwood Ltd Second edition 2000, Woodhead Publishing Limited and CRC Press LLC ß 2000, P. Fellows The author has asserted his moral rights. Conditions of sale This book contains information obtained from authentic and highly regarded sources. Reprinted material is quoted with permission, and sources are indicated. Reasonable efforts have been made to publish reliable data and information, but the author and the publishers cannot assume responsibility for the validity of all materials. Neither the author nor the publishers, nor anyone else associated with this publication, shall be liable for any loss, damage or liability directly or indirectly caused or alleged to be caused by this book. Neither this book nor any part may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, microfilming, and recording, or by any information storage or retrieval system, without prior permission in writing from the publishers. The consent of Woodhead Publishing Limited and CRC Press LLC does not extend to copying for general distribution, for promotion, for creating new works, or for resale. Specific permission must be obtained in writing from Woodhead Publishing Limited or CRC Press LLC for such copying. Trademark notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation, without intent to infringe.
    [Show full text]
  • Visualized How Hard Is Your Water?
    δ Name: ________________ Period: ____ Water Hardness: Visualized How Hard is Your Water? Hardness and salinity are two properties of water that are partially considered in determining the quality of that water. Although a water’s hardness and its salinity are measures of two different things, they refer to very similar concepts. Hardness refers to the amount of calcium, magnesium, and some other trace metal ions (metal ions that are present in relatively small amounts) in water. Calcium and magnesium are two of the three metals that are typically most abundant in water, so some definitions of water hardness only include those two elements: Calcium and magnesium. The harder any sample of water is, the more calcium and magnesium are present in that water. If a sample has very little calcium or magnesium (which can be accomplished through some filtration methods or by drawing from a water source that is naturally low in calcium and magnesium), that water is said to be soft water. Water that is hard is often referred to as hard water. Despite its name, there is nothing physically “hard” about hard water. Ca Limescale and soap scum are two indicators of hard water. Limescale is a buildup of calcium Calcium carbonate, a salt of calcium and carbonate (which is derived from carbon dioxide that has dissolved in water), that deposits on pipes and other surfaces on which hard water CaCO3 frequently comes into contact. Over time, limescale buildup can shrink the diameter of pipes Calcium Carbonate (like in the pipe pictured at the top of the worksheet).
    [Show full text]
  • Descaling of Water
    Descaling of Water Limescale (consisting of mainly calcium carbonate, plus calcium sulfate, barium sulfate, calcium phosphate, magnesium hydroxide, zinc phosphate, iron hydroxides and silica, dependent on the geographical area) is a problem in heated water systems wherever water is obtained from limestone or chalk countryside. It is formed primarily because the solubility of calcium carbonate decreases with increasing temperature. Limescale is only a problem if calcium carbonate deposits calcite crystals, which may form directly or subsequent to metastable hexagonal and fibrous vaterite crystal formation. Orthorhombic aragonite crystals have a higher density and, although intrinsically harder, are less prone to form hard scale, but are only about one kJ mol-1 less stable [107] and favored at higher temperatures. Properties of crystalline polymorphs of CaCO3 -3 CaCO3 crystal Density, g cm Calcite Trigonal (R3c) 2.701 Aragonite Orthorhombic (Pmcn) 2.904 Vaterite Hexagonal (P63/mmc) 2.560 The mechanism by which the magnetic field produces its effect seems down to the presence of a disordered hydrated CaCO3 aggregates [1954], forming liquid emulsions which may be affected by the magnetic field and so convert into different prenucleation clusters and hence different structures on crystallization [1955]. Once formed, crystals are kinetically (if not thermodynamically) stable for hundreds of hours. By drawing water through a static magnetic field (B ~0.1 T , B~10 T m-1, it has been shown that the initial amount of aragonite formed is significantly increased over calcite in samples with and without the presence of dissolved iron [107], although this aragonite eventually changes to calcite [555]. A separate experiment has shown that drawing a pure solution of calcium carbonate and bicarbonate through static magnets (0.16 T) for 5-30 min increases the precipitate formed on degassing the excess dissolved carbon dioxide [1043].
    [Show full text]