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By E. Bonsall, J. J. Brummer, A. R. Graham

"A method and device are described for sampling diamond-drill core by cutting a continuous fillet of constant cross section from the cylindrical surface of the core throughout appropriate sample lengths. The apparatus employs a tapered, abrasive-set, cutting wheel, the conical cutting surface of which projects slightly into a rectangular core-guiding trough set parallel to the axis of rotation. The depth of fillet and thus the amount of sample per unit length can be regulated by adjusting the core guides. The freshly cut fillet itself, by engaging in a guide beyond the cutting wheel, acts to prevent rotation of the core during operation of the device.The cuttings which form the sample are normally collected in a tray below the cutting-wheel and appear at about 80 per cent -100 mesh. They require little or no further treatment or comminution before analysis. Speed, economy and convenience of sampling are thus greatly increased as compared with conventional sampling by im-1>act breaking or sawing, followed by crushing, grinding and sub division for assayAssays from fillets (about 1/20 the cross-sectional area of the core) and from 180-degree segments, from the same ninety-three core-samples, representing 431 feet of nickel-copper mineralization, gave the following results:"

Jan 1, 1968

By Sangjian Zhang, Zhu Xiao, Lairong Xiao, Rushi Chen, Mei Fang, Zhou Li

The copper-graphite metal matrix composites were fabricated by two different production methods: directly sintering with copper and graphite (Cu-Gr composite), and in-situ sintering with cuprous copper and graphite (Cu2O-Gr composite). During the in-situ reaction sintering, a redox reaction occurs at the interface of the Cu2O particles and Gr particles, resulting in the improved physical and mechanical properties of Cu2O-Gr composites. Compared with Cu-Gr composite, Cu2O-Gr composite has a higher compression strength at any given graphite content due to the improved interface bonding and uniformly distributed fine graphite particles in the matrix. Increasing graphite content decreases the mechanical properties of the copper-graphite composites. The compression strength of Cu2O-Gr composite is 50-100 MPa higher than that of Cu-Gr composite. INTRODUCTION Copper-graphite composites have been widely used in industry due to their low density, relatively high strength and hardness, good thermal and electrical conductivity, arc ablation resistance and self- lubrication ability (Grandin & Wiklund, 2018; Han & Xu, 1999; Huang et al., 2017). Electric sliding contact friction pair in the high-speed railway system and motor brush in electric contact components have a very high demand on electrical conductivity and self-lubrication ability of materials. The electric devices need to bear both mechanical load and high electric current. Copper-graphite composites with good mechanical, electric and self-lubrication properties are the best candidates for application in multifunctional electric sliding contact frication components. The relative sliding speed of friction pair is developing towards 100 m/s or even faster, which can withstand the electric flow of more than 800 A, and it is often accompanied with vibration and impact (Guo & Ding, 2008). Conventional wear-resistant materials can no longer meet the current requirements and this promotes the development of copper- graphite composites with excellent comprehensive properties (Ding, Chen, Zhu, Zhang, & Zhou, 2009; Yasar, Canakci, & Arslan, 2007). There are many ways to fabricate copper-graphite composites, mainly including powder metallurgy method, liquid immersion infiltration method, rapid sintering method and electrodeposition method (Kalin & Poljanec, 2018; Kim, Lee, & Han, 2014; Liu et al., 2018; Wang et al., 2018). Each method has its own advantages and disadvantages, and the powder metallurgy method is the most commonly used one due to its simple process, high economic benefit, and industrial production applicability. The common steps of the powder metallurgy method are as follows (Samal, Parihar, & Chaira, 2013): firstly mixing the copper (copper alloy) powders and graphite with a certain ratio, following by die-forming, and then sintering at the high temperature with or without pressure. The advantage of copper-graphite composites is that the graphite distributed in the copper matrix uniformly and it can form a carbon diaphragm preventing the wear of the composite (Fu & He, 2010). However, the bonding strength of the interface between the copper matrix and the graphite is relative low as the combination between them is mechanical interlocking but not metallurgical bonding (Ma et al., 2008). It is meaningful to develop new fabrication technology of copper-graphite composites with better interface bonding, which could provide guidance for the design of copper-graphite composites with excellent comprehensive properties.

Jan 1, 2019

By A. L. Mular

This paper provides a worthwhile contribution to the knowledge needed for calculating and using mathematical models of grinding circuits. The computer search algorithm proposed should remove much of the guesswork as well as reduce computer processing costs and improve the accuracy of estimated parameter values for grinding mill models.

Jan 1, 1970

We describe a new method of characterising the effect of dissolved materials on the rate of coalescence of bubbles in aqueous media. Single bubbles were allowed to rise to meet the surface of an aqueous solution, and the time of persistence between arrival and bursting of bubble was measured as a function of solute concentration. A laser beam was placed just above the surface of the liquid, with a detector in the light path, so that any disturbance at the surface could be seen as a break in the beam. The arrival of a bubble at the surface could be detected from the behaviour of the trace on an oscilloscope, and when the bubble broke, another significant change in the signal could easily be seen. The time between disruptions was reported as the persistence time. The effect of a homologous series of n-alcohols (C1 to C8) on the persistence time was measured, in aqueous solution. It was found that with increasing concentration of a particular solute, the persistence time increased up to a point, and then declined. However the magnitude of the persistence time was found to increase with increasing numbers of carbon atoms in the molecule. Bubbles of 1, 2 and 3 mm diameter were used. Persistence time increased with increasing bubble diameter, the maximum values observed being of order 100 secs. For a given solute, the persistence (drainage) time increased with increasing bubble diameter. The concentration Cmax at which the maximum persistence time was observed, was found to be independent of the bubble size. It decreased uniformly as the carbon number increased, and was well correlated by the function y1/2 (dy /dc) -2 I dc)-2 . There was no apparent correlation with the surface excess at maximum persistence time.

Jan 1, 2006

By A. Hekmat-Ardakan

Conventional hypereutectic Al-Si alloys such as A390 are used principally for the casting of components used in wear applications requiring abrasive resistance such as in engine or compressor blocks. A comprehensive study was undertaken to investigate the potential of improving the mechanical properties of these alloys by the addition of magnesium. A thorough thermodynamic study of the effect of the addition of Mg to the conventional A390 alloy showed that Mg2Si starts to form as a primary phase at 4.2% Mg as well as in the products of the binary and ternary eutectic reactions forming the matrix. Experiments were carried out in producing castings with different cooling and solidification rates of alloys with up to 10% Mg. Mg additions were found to increase the hardness over the as cast alloy due to solid solution strengthening. Also, T6 heat treatment greatly improved the tensile properties of these alloy compositions due to the strengthening effect of the theta-Al2Cu phase. The elongation of these alloys generally decreases marginally with Mg content. The most significant property improvement of the alloys with higher Mg content is the substantial increase in wear resistance. This is attributed to the dispersion of smaller particles of Mg2Si and their coherence with the matrix as compared to the large Si particles in the conventional alloy. A new rheoforming process for A390 is presented that improves the processing of the semi-solid slurry. Structure modification elements were also added to refine the primary and eutectic silicon greatly improving the processing of the semi-solid slurry.

Jan 1, 2011

By G. Morin, F. Chiesa, B. Duchesne

The Quality index is a useful tool allowing to assess the metallurgical quality of aluminium AlSiMg foundry alloys (A356/357). Its value is calculated from the ultimate tensile strength and elongation; it increases with the metallurgical quality of the casting, i.e. with finer dendrites, lower microporosity and inclusion count and lower iron content. This Quality index does not depend on the degree of temper applied during the heat treatment (aging time and temperature). After defining the Quality index, it will be explained how it can be predicted from the knowledge of the local solidification conditions obtained from modelling. The paper will then present four case studies of castings for which the prediction of the Quality index by modelling was made. These case studies from different authors will involve the three most common casting processes used for producing high integrity aluminium castings, namely: sand casting, permanent mould casting and investment casting (lost wax). In all cases, the accuracy of the prediction will be assessed by comparing the predicted Quality index distributions to the experimental values based on the published measured values of the local tensile properties.

Jan 1, 2006

By A. Dubé

Introduction It is common experience that on re-heating a fully martensitic steel below the Ac, point, a softer and tougher structure is formed as the tempering temperature is raised. The mechanism of tempering of plain carbon and low-alloy steels has been the subject of many investigations. In a very comprehensive study, Cohen and associates have recently established three different tempering stages, the last of which reaches completion at about 700°F., with heating rates of 5°F. per minute. This latter stage has been established ta be the carbide-forming stage, so that the steel consists of a mixture of ferrite and carbide, which are the metastable equilibrium phases. Any subsequent changes which take place at higher temperatures below the Ac, point in the absence of graphitization or carbide lattice conversion normally consist of agglomeration of the carbide particles. This naturally results in the softening of the steel. However, in many cases the Ac, point, as determined by dilatometry, thermal analysis, etc., only gives a rough estimate of the temperature where the reaction, ferrite plus carbides to austenite, is initiated. This appears to be especially true in the case of alloy steels in which three phases can co-exist in certain temperature ranges. Bain has given data on the three-phase equilibrium in both manganese and nickel steels. In these steels, the formation of austenite at temperatures just above the AeIL apparently involves the diffusion of the alloying elements to the first pools of austenite, thereby making the process very sluggish. As a consequence, the critical Ac points determined by ordinary methods at normal rates of heating can be quite distant from the true equilibrium Ae temperatures.

Jan 1, 1946

"The Code was developed in 2004 through the Collaboration Agreement between Institution of Mining Engineers of Chile (IIMCh) and the Ministry of Mining (Chile) in Dec 2002. It is an amalgamation of current practices with respect to standards and procedures for exploration prospects, mineral resources, and reserves for the purpose of public reporting. Certification is required to prepare and issue information on mineral assets according to the guidelines that regulate the technical, economic, and environmental aspects that satisfy the conditions set by the Chilean capital and financial markets.The Mineral Resources Committee of the Instititution of Mining Engineers of Chile (IIMCh) is pleased to introduce theCode for the Certification of Exploration Prospects, Mineral Resources and Reserves which is the result of a Collaboration Agreement between the IIMCh and the Ministry of Mining established in December, 2002.This code synthetizes the present practice of the mining industry in regard to standards and procedures applied to exploration prospects, mineral resources, and reserves with the purpose of reporting publicly on financial instruments based on these mine assets in the capital markets. These standards follow general criteria already adopted and applied by capital markets in those countries characterized by a very dynamic and well developed mining sector such as Australia, Canada, Southafrica, United Kingdom, and others. The work done by the Mineral Resources Committee of the IIMCh has had the recognition of the Combined Reserves International Reporting Standards Committee (CRIRSCO) that leads the establishement of an international code in these matters. CRIRISCO is an entity formed by representatives of the countries previously mentioned, a representative of the Society of Mining Engineers of the UStates and a representative of the IIMCh. The Institution thanks the Ministry of Mining, the representatives of these Ministry in the Mineral Resources Committee, and specially the Minister of Mining, Sr. Alfonso Dulanto Rencoret due to the genuine support given to the IIMCh in the preparation of this Code.The Institution also thanks the Superintendencia de Valores y Seguros (SVS) because of the help given continuously to the Committee as well as by the interchange of opinions and suggestions received during the preparation of this document."

Jan 1, 2003

By S. E. Daniel

"Due diligence reviews are an essential part of mineral property acquisitions. One of the primary reasons to complete an environmental review prior to exploration property acquisition is to assess the potential environmental liability. It is critical to identify the potential reclamation costs or existing environmental liability associated with the exploration property. A review of the existing condition of the property and its history can allow prioritization of exploration targets and ease future expenditures for historic damages. IntroductionIn Canada and some other jurisdictions, the purchaser of a property is assumed to know, and is (in the absence of deceit or fraud) financially responsible for, what is purchased. A plea of ignorance, at least from the perspective of environmental liability, is not an acceptable excuse to avoid responsibility (Nelson, 1994). Therefore, if an exploration company (for the purposes of this paper, any organization conducting exploration work) purchases a property that has environmental contamination, the new owner is liable for the cost to reclaim the site to an acceptable level. The cost to reclaim the site is the environmental liability. The new owner is responsible for existing environmental liability of the property, even if the exploration company’s personnel were not aware of the problem. In simplest terms, buyers beware. Therefore, in order to protect the exploration company’s interests, the exploration manager should determine the characteristics of the property of interest prior to purchase or other involvement, and exercise due diligence.The term “due diligence” is often used in the mining industry. To ensure clarity, in this paper’s context, the author has chosen to use the following meaning: “… due diligence is used to describe a detailed data review, generally in connection with the purchase or sale of a mineral property, the approval of a large capital expenditure, or the borrowing of a large sum of money” (Smith, 1997).Directors of the exploration company are held liable for the decisions made, unless they have relied in good faith on,“…a written report of the auditor, or a report of a lawyer, accountant, engineer, appraiser, or other person whose profession lends credibility to a statement made by any such person” (OBCA, 1994)."

Jan 1, 2003

By J. L. Barton, R. A. Murray

"This paper looks at how Syncrude Canada Ltd. is utilizing the Conveyor Belt Monitoring technology developed and patented by the Australian CSIRO and licensed to Syncrude by Conveyor Belt Monitoring of North America, Inc. The technology involves magnetizing the steel cables in the conveyor belts and detecting the fields produced by breaks, gaps or cable ends using special sensors which feed the signals into a multi- channel recorder to provide permanent traces of the various events taking place in the steel cable belts.The data is analyzed and combined with existing belt audit programs, to assist in predicting belt life, change-out criteria and belt design, belt loading and construction. All of these applications of the CBM technology leads to better utilization of resources and forms an integral part of the conveying system reliability program."

Jan 1, 1992

By D. A. Wheeler, Rémi Tremblay

"INTRODUCTIONDuring the last few years, through Column Flotation Company of Canada ltd, the Centre de Recherches minérales has worked on the column flotation of coal, phosphate, feldspar, talc, graphite, copper, lead-zinc and diamond ores. The operating companies and prospective deposits were located in Canada and in other countries. Since these projects were financed by the concerned mining companies, all results remain confidential unless we obtain permission to publish. Three companies have graciously allowed us to use their information which I will describe in this text. These are the Polkowice copper mine in Poland, the North Coast Industries ltd graphite deposit and a talc company which preferred to remain anonymous. I will also describe our 2 inch column which was used for all tests. Data is also given on how to scale-up the 2 inch column to industrial size.Figure 1 presents a schematic of a flotation column. Feed, at a controlled rate and pulp density, enters at about 1/4 of the height of the column from the top. A controlled rate of air is bubbled into the bottom of column through a fine-holed sparger. The column volume between the feed point and the top of the sparger is called the recovery zone. Tailings, at a controlled rate, always slightly greater than the feed rate, discharges from the bottom of the column. This difference in feed and tailings flowrates is called the bias. The floated mineral is carried through the recovery zone on air bubbles which rise into the cleaning zone which is that column volume between the feed point and the overflow at the top. As the bubbles rise in this zone they are washed of gangue material by wash water which enters over the top of the froth layer. The froth layer is maintained at a given depth during flotation but this depth will depend on the froth cleanliness, for quite a bit of cleaning by wash water is accomplished in this layer."

Jan 1, 1988

By S. P. Lowe

Flotation testing of Flin Flon ore was started in the Denver laboratory of Complex Ores Recoveries Co. in March, 1926. There had been a considerable amount of flotation testing previously which had shown possibilities of success, and it was felt that, with the increased knowledge of flotation and the comparatively new reagents then available, flotation held out the best prospects for a successful commercial treatment of this ore. There remained available for this experimental work a small amount of the rejects from a thorough sampling of the mine and some ore from the mine dump.

Jan 1, 1930

By R. Lasmanis

"Washington State's diverse geological setting is reflected by its several types of porphyry Cu-Mo deposits. All are associated with calc-alkaline intrusions, and they range in age from Jurassic to Miocene.The largest is the Mount Tolman Mo-Cu deposit located in the Omineca Belt. It contains 2.18 billion tonnes of material averaging 0.093% MoS2 and 0.09% Cu. There are intermediate-size Mesozoic deposits in the Intermontane Belt. The Cascade volcanic arc hosts small- to medium-Tertiary deposits. Among these, of particular interest is the Sunrise breccia pipe, which has been explored over a vertical distance of 1000 m. It contains reserves of 64.6 million tonnes averaging 0.319% Cu and 0.071% MoS2 with significant tungsten values. The Glacier Peak deposits have potential resources of 1.7 billion tonnes averaging 0.334% Cu and more than 0.015% MoS2 and also contain tungsten. The Margaret deposit can be classified as a porphyry Cu-Au type; it has reserves of 200 million tonnes averaging 0.434% Cu, 0.0175% MoS2> 0.27 g!t Au and 1.92 g!t Ag. Drill intercepts of the North Fork deposit also show significant gold values.Mineralization and hydrothermal alteration of these deposits are typical of porphyry deposits, although some differences can be noted. The Mount Tolman molybdenum deposit contains topaz alteration zones and is transitional between a plutonic type and a Climax-type molybdenum system. Other deposits, such as the Kelsey, Mazama, North Fork, and Margaret, are low-sulphide systems that contain significant amounts of magnetite."

Jan 1, 1995

By J. L. Jambor, E. J. Reardon, E. C. Appleyard, J. A. Cherry

Abstract- Since the 1957 initiation of deposition of mill tailings at the Heath Steele mine, New Brunswick, periodic detailed studies of the tailings geochemistry and mineralogy have been con­ ducted, thereby providing a unique opportunity to examine the geochernical evolution of a sulfide- rich mine-tailings impoundment. When deposited, the tailings contained about 85 wt% sulfide minerals, 1 wt% to 3 wt% carbonate minerals, and 12 wt% to 14 wt% aluminosilicate minerals. Mineralogical examination of samples of the tailings from deep in the impoundment indicates that little oxidation occurred prior to tailings deposition. The mill process-water deposited with the tailings was neutral to slightly basic and contained low concentrations of Cu, Pb, Zn and As. Sampling of the tailings five years after deposition indicated that sulfide-oxidation reactions, occurring near the tailings surface, had decreased the tailings-water pH and increased the concentrations of Fe, SOi-, Cu, Zn and Pb (up to 10 000 mg/L, 25 000 mg/L, 2.5 mg/L, 200 mg/L, and 4.5 mg/L, respectively) . In 1975, ten years after decommissioning, the tailings could be divided into three zones: an upper oxidation zone in which sulfide oxidation is actively occurring, a hardpan layer, 15 cm to 20 cm thick, composed of tailings cemented by secondary Fe minerals, and an underlying reduction zone in which the tailings are relatively tinoxidized (Boorman and Watson, 1976). Chemical analyses indicated the presence of low-pH waters containing very high concentrations of SO42- , Fe, and other metals (up to 63 600 mg/L SO42-, 28 600 mg/L Fe, 10 mg/L Pb, 600 mg/L Cu and 4000 mg/L Zn), suggesting that there was a period of intense sulfide oxidation between five and ten years after tailings deposition. More recent sampling, conducted some 20 years after the end of tailings deposition, indicates that relatively little change has occurred in the last ten years, thereby suggesting that the hardpan layer has provided an impediment to the downward movement of dissolved constituents . Analyses of the tailings solids show increased accumulations of many metals at or near the depth of the hardpan layer. Evaluations of the long-term evolution of the tailings can be enhanced by comparison of descriptions of the tailings with descriptions of the gossan that overlay the massive­ sulfide orebody prior to mining. At Heath Steele, this comparison suggests that many of the mechanisms controlling the distribution of metals in the tailings will probably persist over geologic time.

Jan 1, 1992

By Linda Hodgson

1. Introduction ?Northgate Minerals Corporation is a mid-tier gold and copper producer with mining operations, development projects and exploration properties in Canada and Australia. ?Kemess Mine is Northgate?s principal operation. Where in the world is Kemess? ?Kemess is located in north-central British Columbia,430 kilometres northwest of Prince George. ?The Kemess South complex consists of an open-pit mine, a 52,000 tonnes per day mill and various ancillary support facilities including maintenance shops and housing for Kemess' 340 full-time employees.

May 1, 2010

By T. A. Lloyd

"This paper indicates the extent to which Canadian coal mine operators have taken advantage of developments in the science and technology of coal that would allow them to better satisfy changing market demands through improving the properties of their products. At some mines, no attempt is made to alter the coal from its as-mined condition, but at most mines grading into various size ranges and hand-cleaning of lump sizes is undertaken.Over-all, Canada Jags behind most of the other major world coal producers in the proportion of its coals being processed in wash plants. To some extent, this is due to the fact that a high proportion of the coal production satisfies market demands without such treatment. On the other hand, a few of the coal mines in Canada, which produce about 25 per cent of the nation's total coal output, have in operation some of the most modern coal beneficiating equipment available, including jigs, flotation cells, water cyclones, centrifuges, disc filters and thermal dryers."

Jan 1, 1968

By T. Niedoba

Coal as an energetic raw material is characterized by many features that determine its quality. The data concerning coal are usually treated as independent values, despite the fact that this kind of approach is not always appropriate. In the paper the dependencies between sulfur contents and volatile components in coal and particle size and density were analyzed. The method of ordinary kriging is applied to experimental data to describe this relationship; this method can be used for particles of any size and density. An example of the application of this technique is presented for energetic coal Type 31, originating from one of the Polish hard coal mines in Upper Silesia. Results from ordinary kriging are in good agreement with experimental results. Similar analyses can be performed for other properties of coal material, such as ash content, Roga number, and moisture. On the basis of the data obtained by ordinary kriging, a more comprehensive multidimensional model is described, which can characterize certain deposits or strata from which the analyzed materials originate. This is superior to basing the model only on experimental data, which often is limited by size of the sample. The results obtained by ordinary kriging applied to various types of coal would allow more precise analysis of individual properties of the studied materials and increase the ability to determine significant differences between them. This method can be also applied to other types of mineral raw materials, such as copper ore.

Aug 1, 2013

By R. A. Campbell

Pig iron and silicospiegeleisen were produced experimentally from a very low-grade manganiferous iron ore from Steep Rock, Ontario, by a two-stage electric smelting process. The most favourruble operating conditions were determined for each stage. Cement clinker then was made by calcining the slag from the second stage of smelting, with additional limestone and alumina. (This slag would normally be a waste material). The cement clinker produced had the composition of commercial Portland cement, and met the physical test requirements of the Canadian Standards Association Specification A5-1951 for normal Portland cement as well as could be expected for a material produced on .such a small scale.

Jan 1, 1958

By M. Aljarrah

The phase equilibria in the Mg-Al-Ca system was investigated experimentally by differential scanning calorimetry (DSC) and X-ray diffraction (XRD) techniques similarly the Mg-Al-Sr system has been studied using DSC and XRD as well as scanning electron microscopy/energy dispersive spectrometer (SEM/EDS) and quantitative electron probe micro-analysis (EPMA). A new ternary solid solution MgxAl4,xSr was confirmed in Mg-Al-Sr system, which is a substitutional solid solution of Mg atoms in Al4Sr. Maximum solubilities of 21.3 at.% Al in Mg17Sr2 and 11.4 at.% Al in Mg were observed. It was also noticed that Mg38Sr9 dissolved 12.5 at.% Al. In the Mg-Al-Ca ternary system, one of the invariant transformations predicted by thermodynamic modeling was verified experimentally and found to occur at 512°C with composition close to 10.8 at.% Ca, 79.5 at.% Mg and 9.7 at.% Al. A ternary solid solution (Mg,Al)2Ca was confirmed where large solid solubility of Al in Mg2Ca was observed.

Jan 1, 2006

By J. S. Phipps, D. R. Skuse

"Aqueous slurries of fine particle size calcium carbonate are used in a diverse range of end-use products. In many cases, the end-use performance is governed by the fineness of the particle size distribution. In turn, the maximum fineness of the particle size distribution is primarily determined by the efficiency of the dispersants used during the production process. Here, we report the sodium polyacrylate mediated dispersion of calcite and kaolin. Firstly, we report a colloid chemical description of the dispersant behaviour and attribute the stabilization to both steric and electrostatic mechanisms. Secondly, we describe how the understanding developed in the first part of the study can be utilized to produce more effective dispersant systems which allow the preparation of added value, higher solids and finer particle size calcium carbonate slurry products. IntroductionConcentrated aqueous dispersions of fine particulate kaolin and calcium carbonate are used extensively in the coating of paper. Currently, more than 10 Mt of such dispersions are used annually in North America and Europe alone, and worldwide consumption is growing at around 3% per year.Generally, paper is coated to enhance its visual appearance. Firstly, coatings improve the optical properties of the blank sheet, i.e., its brightness (or whiteness), opacity and gloss. Secondly, they improve the physical properties of the sheet that will influence the quality of the final printed image, such as surface smoothness, porosity, and ink absorption. In order to achieve these aims economically, paper coatings must be applied at high speeds and with minimal drying costs.Kaolin and calcium carbonate pigments are the major components of most paper coating formulations. Particle size distributions are chosen to maximize the optical benefits that they confer, and to allow the production of formulations that can be easily pumped, handled and coated. Coating pigments are generally produced and transported as slurries, and so it is important to obtain dispersions with the highest possible solids content, both to minimize drying costs and the quantity of water transported. This paper examines the dispersant technology that is currently used in the industry and the mechanisms by which it functions, and illustrates ways in which this technology has developed and could be further improved in the future."

Jan 1, 2003