Search Documents

By Bruno A. Fichna

Longwall mining offers low cost potential for coal with high capital investment. As opposed to two shifts-per-day operation in most long- walls, Saarberg Mines in Germany increase utilization of capital by operating their longwalls around the clock. Differentiation between capital and operating costs, corrective maintenance versus preventive maintenance, improved roof conditions, and economical life of equipment was investigated. A surprisingly high degree of improvement was attained. Capital costs at Saarberg longwall coal mines have been reduced through a step-by-step research and trial program. This reduction was particularly influenced by the high performance pilot longwalls at the Ensdorf mine. The following presentation shows data and figures of those longwalls. End results were 40% reduction in capital costs, which could contribute favorably to investment decisions in the coal industry in a supply side economics environment.

Jan 1, 1982

At Namdeb, submerged beaches are earmarked for sampling and future mining and various sampling configurations are tested for optimality through the use of spatial simulations. For the creation of these virtual orebodies, basic statistics and variograms are needed, but in this specific instance no data exists from which the necessary parameters can be determined. The best that can be done is to use proxy data from onshore beaches, with adaptations where needed. The reworking of raised beaches during periods of rising and falling sea levels in some cases destroyed the internal beach structures, and it is very difficult to determine the variograms. A method is proposed whereby simulated annealing is used to adjust the sample locations to align the data pertaining to beach crests or cliff lines, thus improving the variogram structure along the shoreline in the direction of the highest geological continuity.

Jan 1, 2014

By S W. Kingman, D Whit, I S. Lowndes

The use of compressive crushing equipment such as gyratory crushers within minerals processing plants can potentially generate large quantities of dust. Remedies to this problem include the retrofitting of shrouds, enclosures, local exhaust ventilation (LEV) systems and water suppression systems. The single or combined application of these systems must be optimised to ensure they operate efficiently. It is desirable that the future design planning of such facilities include integrated dust suppression and/or removal systems to ensure material delivery rates are maintained and the welfare of the workforce is protected. The characteristic release of dust and the disturbance to the surrounding ventilation airflow is investigated by the construction and solution of computational fluid dynamic (CFD) models validated by data obtained from scale experiments. A 3D computational model was constructed using the FluentTM CFD software to represent the background ventilation regime within an underground crushing installation. The falling ore is represented as a continuum granular fluid falling under gravity from the raised bed of the dump truck. Transient path lines are computed to simulate the updraft airflow generated by the tipping process and indicate the dispersion path of any entrained dust. The relationships between the falling ore material, the displaced air and the shear induced flow are determined by an analysis of the computed volume/mass flow rates predicted across the crusher opening. An analysis of the airflow patterns predicted by the CFD simulation models indicates strong shear flows induced between the tipped material and the surrounding airflow in the vicinity of the crusher during tipping, and a strong influence of the background ventilation regime on the path taken by this shear flow. Scale experimental studies were conducted to characterise the induced shear flow and visualise the potential entrainment and transport of dust. An analysis of these experiments is presented.

Jan 1, 2005

By Robert A. Jankowski, J. Drew Potts

The Bureau has identified several ventilation techniques and a water spray application for reducing auger mining dust levels. The dust control methods all work by improving air quantity or flow patterns at the face. Section airflow is maximized by reducing air leakage between entries. Sealing stoppings with brushed- on mortar, containing fiberglass additives, reduces leakage. Heading airflow is maximized by properly installing the brattice curtain and keeping the area between the curtain and rib free from obstructions. The brattice curtains should be hung at least 1.7 m (5.5 ft) from the ribs in 7.9 m (26 ft) wide entries and kept less than 4.6 m (15 ft) from the face. A tight curtain seal is created by using the mine air pressure to force the curtain against the timbers, roof and floor of the mine. Using both a blowing curtain and an exhausting curtain will isolate some face workers from dusty air. The Bureau designed, auger clearer spray system, can be used to force heading air across the active face. Laboratory tests indicate that the auger clearer spray system can increase face velocities by more than 0.5 m/sec (100 ft/min), while using less than 0.13 l/sec (2.0 gal/min) of water.

Jan 1, 1989

By Jerry R. Riding

Metallurgical process methods have seen dramatic improvement over the past fifty years. As these improvements have come about, more and more emphasis has been placed on obtaining accurate and rapid analysis of the metallurgical processes. Well-defined conventional laboratory analysis procedures which have proven to be reliable were developed early in the mineral industry's history; however, these conventional procedures, which have not changed appreciably in fifty years, have the serious drawback that they are too slow to be of appreciable value in automatic control of the processes. For example, the assay results normally become available to a mill operator from eight to twenty-four hours after a sample is taken. Since the desired mineral separation can only be made while the minerals are in the flotation circuit, conventional assay results provide information similar to postmortem reports. Consequently, using conventional procedures, the mill is operated with information from an earlier period of time, which may not reflect current conditions. In recent years there has been a steady increase in the volume of required samples. At the same time, labor, material, and overhead costs have continued to rise causing the cost per assay to reach an alarming level. This rising cost per assay, plus the increasing demand for rapid analysis necessary for control, has caused the mining and metal processing industries to look toward other techniques to solve these problems As a result, X-ray fluorescence which can provide on-stream analysis necessary for control, as well as perform numerous laboratory assays at lower cost and at a much greater speed than conventional methods, has gained wide-spread attention. In addition, multichannel X-ray fluorescent instruments are now available which have been perfected to the point where the analysis of the most important chemical constituents is available within one minute after a sample is presented to the X-ray analyzer. Because of these obvious advantages, extensive use is being made today of X-ray analysis in the mining industry to analyze slags, ores, and mineral content of rocks. The results are used to make quick decisions for both mining and beneficiation of metals. For example, X-ray systems which provide rapid on-stream analysis of the slurries at desired points Fn metallurgical processes have recently been developed. The successful application of these systems has moved the milling process a step closer to fully automatic control.

Jan 1, 1969

By B. G. Cousins, L. Racine, R. S. MacPhail

"FLEX 31 is a chemically enhanced sodium isopropyl xanthate that has shown improved collection properties over SIPX for copper-bearing and copper-activated minerals. Characteristics such as improvement of recoveries with lower dosages and high pyrite and pyrrhotite rejection capabilities have all been exhibited by FLEX 31.The most improved results have been seen insphalerite flotation. Plant trial work carried out in the zinc circuit at the Louvicourt Concentratorin northern Quebec has produced data showing superior grade and recoveries from rougher concentrates that previously had not been attain-able with other reagents effectively. The improvement over SIPX adds up to an almost$1,000,000 annual improvement on the mine’s bottom line at present zinc prices.IntroductionSodium Isopropyl Xanthate (SIPX) is one of the most popular flotation chemicals on the market today. Somewhat more specific than amyl xanthates, SIPX is used in a variety of ores like copper/zinc, lead/zinc, arsenopyrite/pyrite, and many others (Melis et al., 1991). An investigation carried out by Tennants Research Technology Applications (TRTA), a division of Charles Tennant & Co. (Canada) Ltd., produced a chemically enhanced SIPX that has shown all the advantages of normal SIPX along with improved recoveries of copper and copper activated minerals. The new product has been named FLEX 31. Currently, FLEX 31 is manufactured at the Prospec Chemicals, another division of Charles Tennant & Co. (Canada) Ltd.A large amount of laboratory testing pro-grams have been carried out with FLEX 31 todate (MacPhail and Cousins, 1995; Cousins and MacPhail, 1996). One of the minerals that has a defnite affinity to improved fotation is sphalerite (ZnS). Once activated with copper sulphate, sphalerite has produced some of the most spectacular test work when FLEX 31 is compared directly to SIPX. Plant trials of FLEX31 at Aur Louvicourt Inc. carried out in 1995show that FLEX 31 is far superior to SIPX for activated sphalerite flotation."

Jan 1, 1997

By Robert MacPhail, Louis Racine, Bret G. Cousins

"Sodium Isopropyl Xanthate is employed in a wide variety of sulphide flotation procedures due to the specificity over other xanthates and the cost savings over other sulphide collectors such as thionocarbamates, xanthogen formates and dithiophosphates. An investigation carried out by Tennants Research Technology Applications (TRTA), has produced a chemically enhanced SIPX that has shown all the advantages of normal SIPX along with improved recoveries.Currently, FLEX 31 is manufactured at the Prospec Chemicals xanthate plant in Fort Saskatchewan, Alberta, Canada. Prospec, founded in 1983, produces approximately 4500 tonnes of xanthates per year and is presently undergoing expansion to produce approximately 6000 tonnes. The proprietary process for FLEX 31 is a new addition to plant operations that include the production of xanthates, thionocarbamates and xanthogen formates.This paper will cover the testwork on the zinc flotation circuit at the Louvicourt Mine in Val d'Or, Quebec. This testwork indicated that FLEX 31 could replace SIPX due to the ability of the FLEX to improve zinc flotation kinetics without adversely affecting final concentrate grade. FLEX has presently replaced SIPX in the zinc circuit at Louvicourt.BackgroundThe Louvicourt deposit is hosted by greenschist facies Archean volcanic rocks located in the southeast portion of the Abitibi Greenstone Belt. In the Val d'Or area, the volcanic rocks form an east-west striking, steeply dipping and south-facing sequence composed of thick mafic and ultramafic flows of the Lower Malartic Group.The joint venture has three partners-Aur Louvicourt Inc. (30%), Novicourt Inc. (45%) and Teck Corp (25%). Aur Resources holds 30% interest through Aur Louvicourt, a wholly owned subsidiary and is the operator of the project. Novicourt Inc. is 60.9% held by Noranda.Approximately 75% to 85% of Louvicourt's revenue comes from the sale of copper; 10% from gold (in the copper concentrate); 7% from zinc and 3% from silver (also in the copper concentrate) The copper at Louvicourt is fairly ""fast floating"". About 60% of the copper in the ore can be concentrated in the first flotation cells with feed grades of approximately 4% copper.The initial testwork and pilot trials had indicated that it would be difficult to achieve zinc grades over 52% and recoveries would have to be kept at a level amenable to salable concentrate grades. The actual mill results, with a fine regrind, achieved zinc grades of 55% to 56% at about 75% recovery."

Jan 1, 1996

By M Darby, B Burdett, F Lovell

The results of the process control improvement project aimed at improving the quality of Australian Bulk MineralsÆ (ABM) iron ore pellets produced by four vertical shaft furnaces are very positive. These results are achieved through process stabilisation and optimisation, improvement in process monitoring and taking early corrective actions when operating variables were outside the target ranges. A number of benefits are obtained from this project. These benefits include: More consistent and improved pellet quality. The average cold compression strength (CCS) value of pellets produced during the eight-month trial is 260 kg/pellet, which is 16 kg/pellet higher than that produced during the 12 months prior to the trial (244 kg/pellet). Reduction in the heat input by eight per cent, from 727 MJ/tonne to 668 MJ/tonne. Reduction in bentonite rate by six per cent, from 7.1 kg/tonne to 6.7 kg/tonne. Increase in the furnace throughput rate by four per cent and additional production of 10 000 tonnes per annum through process stabilisation. Better understanding of the process behaviour. This knowledge is valuable not only for setting the target operating conditions but also for developing the ABM expert system to control the process.

Jan 1, 2005

By Robert S. MacPhail, Chilombo Henry, Arnold Kabamba, David Mukelebai, Suresh Thirunagari, Bukali Victor, Yoram Kapai, Chomba Leonard, Kanna Amarasingham

"FLEX 31 is a chemically enhanced sodium isopropyl xanthate. Developed by Charles Tennant & Co (Canada) Ltd and has shown improved collection properties over SIPX for sulphide minerals flotation. Improvement of recoveries, grades, faster kinetics, lower dosages, high pyrite and pyrrhotite rejection capabilities have all been exhibited by FLEX 31. Recent plant trial carried out in the copper circuit at one of the largest copper mine in Zambia shown over US $ 2.00 Million annual improvement on the bottom line over SIPX at current copper prices. Data produced also showed superior grade and recoveries from rougher concentrates that previously had not been attainable with other reagents effectively. Flex 31 has also shown positive outcomes with zinc, Copper/Zinc, arsenopyrite and copper/molybdenum ores.IntroductionSodium Isopropyl Xanthate (SIPX) is one of the most popular flotation chemicals on the market today. Somewhat more specific than amyl xanthate, SIPX is used in a variety of ores like copper/zinc, lead/zinc, arsenopyrite/pyrite, and many others (Melis et al., 1991). An investigation carried out by the research division of Charles Tennant & Company (Canada) Limited has produced a chemically enhanced SIPX. This product has shown all the advantages of normal SIPX along with improved recoveries of copper and copper activated minerals. The product was named “FLEX 31”."

Jan 1, 2016

By E. Gybbon Spilsbury

(Pittsburg meeting, March, 1910.) THE recovery of gold and silver from their ores by means of the cyanide process has been so successful in the last few years that any radical improvement would seem impossible; yet the appliance to which I wish to call attention in this paper is really a radical departure from the methods now in general use. The most modern and approved of these, known as the all-sliming method, depends for its success on the grinding of the. ore so fine that practically 90 per cent. of it will pass through a 200-mesh screen. The slimes thus produced are then agitated and aerated in tanks of various types. The main object of this treatment is to insure such a thorough admixture of the pulp and solution that every particle of the ore is surrounded by a volume of solution sufficient to insure the dissolving of the whole of the gold- and silver-content. In addition, in order to expedite the action of the cyanide, and to oxidize such elements as would, if left in their active state, become cyanicides, air is blown in under pressure. In the Pachuca tank, this air is the active and sole means of agitation. The chief objections to all the methods off agitation used heretofore are the expense of operating and maintaining the mechanical devices for keeping the pulp in suspension, and the length of time required to obtain a fairly complete extraction. of the values. These objections are inherent to any method of agitation effecting a circulation of the pulp and the solution together, by giving the whole mass a circular movement, as in the low-tank system, or a vertical circulation, as in the Pachuca-tank system. In both methods, the particles of ore are kept traveling in the same direction as the solution, and with very little difference of speed; so that, while the whole mass is in

May 1, 1910

By B K. Da, S A. Balaji, G P. Roy, T K. Dutta

The raw material handling complex at the Durgapur steel plant provides iron ore, crushed coke and flux to two sinter plants. Either some facilities were not envisaged or not properly designed before the project stage which caused problems during operation of the plant. The absence of an in situ roll turning facility, used to increase maintenance activities for disassembly, transportation of rolls to central machine shop and assembly of rolls, led to decreased crusher availability and increased activities for the maintenance crew. The provision of a smaller vibro feeder/screen in place of a suitable sized screen caused jamming of the screen deck, adversely affecting screening efficiency and the crushing index of crushed coke. Some design modifications and developmental work was undertaken, such as the development and installation of an in situ roll turning facility in the existing limited space, achieving low feed (0.1 - 0.2 mm/rev), lower cutting speed of 30 - 40 m/minute for 350 BHN hard roll, which was also a difficult engineering challenge to bring within the tolerable limit of vibration. This was successfully achieved. Modifications to the screen deck, introduction of differential speed crushing and modification to the vibro screen and vibro feeder for uniform distribution of feed have been incorporated. These innovative design modifications to the in situ roll turning have led to a drastic decrease in maintenance activities and an improvement in the crushing index. Modifications to the screen have resulted in the elimination of jamming and improved screening. Modifications to the vibro screen before the primary crushers and to the vibro feeder before the secondary crushers have prevented excessive wear in the central portion of rolls, ultimately leading to increased roll life. Incorporation of differential speed crushing has resulted in an increased crushing index and decreased generation of micro fines. All the above modifications have led to distinct improvements in equipment availability, increased roll life and a decrease in maintenance activities and improvement in crushed coke granulametry, ultimately resulting in improved productivity and quality of iron ore agglomeration at the sinter plant. The innovative design modifications mentioned above are discussed in detail in this paper.

Jan 1, 2005

By Sib N. Mukherjee

Main ventilation fans are used in all the mines and they run continuously 24 hours a day and 365 days in a year. Any improvement in their performance can lead to considerable power saving. The basic principle for selection, operations, and related measures are discussed in brief in the paper. The contributions of different elements of mine fan on its performance are discussed in brief. The means to improve efficiency of a running fan is also discussed and the importance of saving even 1 Kwh is elaborated. It is found that the cost of the energy saved may even permit a replacement fan to be procured in a few years time.

May 1, 2007

By R. Shiva Kumar, G. Sreedhar, S. Sharma

Some of the Indian origin iron ore deposits located in Bellary, Karnataka province are having peculiar characteristics of Iron ore deposits (Hematite) having Iron above 64% and 30-40% lump (-30+6mm) recovery which are not suitable to use in blast furnace due to not meeting the specification of Tumbler Index and Abrasion Index. In general for high grade Iron ores, process flow sheet involves crushing and screening (dry/wet). In the contest of high grade Iron ores located at Bellary sector of Karnataka state in India, lump generated from this process could not attain the required physical properties (Tumbler Index, Abrasion Index) and metallurgical properties , even though the grade of the lump ore is above 64% Fe. Washing techniques like Drum scrubber and Log washer play major role in improving the metallurgical properties of Iron ore lumps by removing the light and hard layers of clay, silica coated over the lumps. In this study the effects were compared of drum scrubbing and log washing on iron ore lumps. It is found that by incorporating simple washing technique i.e. drum scrubbing or log washing, Tumbler Index of Iron ore Lumps could be increased from 74% to 78% which is acceptable for use in Blast furnace. From the Drum scrubber and Log washer tests, it is clear that Log washers have an edge over Drum scrubber in removing hard coated clay on surface of Lumps. This simple washing technique facilitate us to utilize the lumps directly in blast furnace and eliminate the unnecessary crushing and grinding of the ore so as to meet the specifications of Sinter fines and pellet feed.

Jan 1, 2014

By Cuim R., M. L. Li

Fankou Lead-Zinc Mine produced pyrite concentrate (P.C.) from the zinc tailings by rougher and scavenger flotation before 2010, with the averaged S grade of 40.54% at recovery of 79.34% ( to the feed of S circuit). On the one hand, the economic value of P.C. increases with its purity, on the other hand, when the S grade of P.C. feed to sulfuric acid manufacturer is over 47%, the pyrite cinder can reach a high Fe grade of 62% which can be directly sold as iron concentrate. On this background, engineers in Fankou Mine set the P.C. with S grade of 47% as target. The direct way to reach that goal was to clean the rougher P.C.. Lots of cleaning flotation tests were conducted and the compromised strategy was to produce two ranks P.C. with the S grade of 47% and 38% at the recovery of 44.20% and 36.17%, respectively. The dual-product flowsheet was successfully industrialized in 2010. In order to further improve the quality of P.C., gravity separation was introduced into the flowsheet. The numerical simulation and separation tests were performed to evaluate the beneficiation and classification performance of hydrocyclone as it treated the rougher P.C.. It was shown that the underflow of hydrocyclone could addressed the S grade of 47%, and the finer size overflow could also be enriched to P.C. with S grade of 47% by flotation, due to the contained pyrite with well liberation. That is to say, with the ingenious addition of hydrocyclone to treat the rough P.C., single P.C. with S grade of 47% could be achieved. The new flotation-gravity separation flowsheet was commissioned to produce the high quality P.C. at the end of 2013. The averaged S grade is 47.20% at recovery of 82.26% in 2014. The two steps flowsheet improvement maximizes the enterprise benefits and leads to simple utilization of Fe in pyrite in downstream industry.

Jan 1, 2018

By Juliano Braz Possatti, Arnaldo Carneiro Salles, Cleudson dos Santos Rego, Leandro de Lucas Mendes

The increase in customer demand for steels with higher surface requirements, associated with the need to increase ArcelorMittal Tubarão's HSM productivity, it was necessary the development of controls and actions to reduce scale losses within the scenario of high productivity. This article describes the path followed by the hot strip mill team in order to reduce the occurrence and severity of scales.

Oct 10, 2019

By Takashi Sasaoka

Indonesia is the second largest coal exporter to Japan, accounting for about 30 M tons annually. They produced about 150 M tons in 2005, over 99% of which being from open-cut mines [1]. However, the conditions of surface mining are becoming worse each year: the stripping ratio is increasing, approaching the economic ratio and the infrastructure for coal transportation from inland mining areas is insufficient for such intense mining operations. To meet the demand for coal in Indonesia and the rest of the world, underground mines have to be developed. At present, there are only five small underground mines, three of which are old and the other two have only recently begun mining operations [2]. However, severe ground control problems have been occurring regularly, roof falls in particular. At a new mine developed from the highwall, a large bolted roof fall occurred at the heading face, killing two miners. Unfortunately, mining engineers and/or miners in this mine do not have a lot of experiences, expertise and know-how concerning the operations of underground coal mines. Since 2001, Japan has started a ?five-year plan for coal technology transfer? to fill Japan?s moral obligation as the largest coal importer in the world. The research team for this accident was organized and the on-site investigation was conducted in order to find the cause of this accident and make the solution. This paper describes the roof fall accident at the mine, discusses its causes and mechanism and suggests the introduction of some techniques for improving the current support system considering the strata and stress conditions by means of field observation and finite element modeling.

Jan 1, 2007

By Rameshwar Sah, Somasekhar Pitchika, Akhil Singh, Seenivasan Rajiah, C. B. Dayanand, G. Balachandran

In the sintering of iron ores, the partial substitution of anthracite coal for coke breeze has been considered to be an effective way of reducing emissions and improvement in sintering properties. In the present study, the combustion characteristics of the anthracite coal and coke breeze were investigated and its influence on product sinter quality and sinter flue gases is being monitored. Pot trials are carried out with different coke breeze ratios, 0%, 40%, 50%, 60%, and 100%. It is found that as the percentage of anthracite coal is increased from 0 to 100%, the sintering time decreased from 24 to 20 min, and the productivity increased from 2.25 to 2.60 t/h/m2. Up to 60% anthracite coal substitution Tumbler index (+ 6.3 mm%), Product yield (+ 5 mm%), and fines generation (− 5 mm%) is found 62.29%, 85.17%, and 15.33%; moreover, hematite ( Fe2O3), magnetite ( Fe3O4), calcium ferrite phases ( CaFe2O4, CaFe3O5), and Silico ferrite of calcium and aluminum (SFCA) are major mineral phases found during microstructural analysis of product sinter. Keywords Sintering · Anthracite coal · Combustion rate · Productivity

Jun 2, 2022

"In mechanized mining, poor equipment efficiency (availability, utilization, productivity, and quality) can endanger the success of the operation. This case study will show how an initiative to improve equipment performance developed into a comprehensive turnaround plan for the mine that placed it in the forefront of performance achievement.As part of a company-wide review process, poor overall equipment effectiveness (OEE) was identified as a major reason for the mine not achieving its targets. A project to improve the OEE identified eight improvement areas (elements) that contributed significantly to the poor performances. Measurement metrics were determined for these elements, followed by determination of baseline and target (improved) key performance indicators (KPIs). Cost savings associated with the improved efficiencies were calculated and tracked throughout the project. The mine team determined the specific actions required to achieve the target KPI in each element. These were individually developed and managed like mini-projectswith allocated responsibilities for delivery. The paper will indicate how this OEE improvement initiative triggered an improvement in almost all sections of the mine. Soon after launch, the initiative gathered momentum as the KPIs starting to improve. A visible tracking system exists at the mine and each employee can see the improvements and feel the success. The original eight elements were extended by five more, and the mini-projects grew as participants saw the success of the initiative.This paper concludes that through management and worker involvement, visible measurement and controls, and carefully chosen improvement elements, the mine was turned around. It is now achieving and exceeding its targets, and employee relations and motivation as well as safety have improved considerably. All of these achievements are reflected in the bottom line."

Jan 1, 2016

By N. Sahay

Improvement in work place environment by conventional methods viz., installation of higher capacity fan, fans in parallel operation or booster fan is a risky proposition in many coal mines in India because of difficult geo-mining condition such as shallow depth, multi seam workings having thin parting and inter connected goaves one above the other. The situation is further worsened if the mines have fire affected sealed off area connected to different ventilation circuits. On many occasions circulation of more air quantity by increasing fan pressure have resulted in initiation of spontaneous heating. To address these problems, authors have made some improvement in conventional Dynamic Balancing of Pressure Technique and worked out few ventilation schemes which are aimed for neutralization of pressure differential across sealed off area at the same time having improvement in ventilation in the mine. The excess pressure differential across sealed off area is mainly caused by introduction of higher capacity fan. Similar situation prevailed in one of the mines of Jharia Coalfield, India. The problem was solved by application of the above technique. In this paper, brief description of the technique, the problem in the mine, results of investigation, computer simulation studies of various schemes and methodology adopted for implementation of the technique in the mine have been discussed in some detail. Keywords: Dynamic Balancing of Pressure Technique, Spontaneous heating, Work place environment.

Jan 1, 2003

By A. Ferreira Morgado

The sodium smectitic clays (bentonites), have more industrial applications in that class of mineral, a driving force to obtain this mineral. In Brazil, there are several occurrences of smectitic clays, unfortunately they are polycationic, with a distribution of several exchangeable cations, where the cation sodium occurs in minor quantity. In this work, the original polycationic smectitic clay was firstly proper characterized and then treated with sodium carbonate obtaining homoionic sodium smectitic clay. The rheological tests in the optimized sodium smectitic clay showed good results for drilling fluids, typical of a sodium bentonite ones.

Jan 1, 1999