EP0201338A2 - Production d'un combustible charbon-eau - Google Patents

Production d'un combustible charbon-eau Download PDF

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Publication number
EP0201338A2
EP0201338A2 EP86303504A EP86303504A EP0201338A2 EP 0201338 A2 EP0201338 A2 EP 0201338A2 EP 86303504 A EP86303504 A EP 86303504A EP 86303504 A EP86303504 A EP 86303504A EP 0201338 A2 EP0201338 A2 EP 0201338A2
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EP
European Patent Office
Prior art keywords
coal
flotation
refuse
ash
dewatering
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP86303504A
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German (de)
English (en)
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EP0201338A3 (fr
Inventor
Ralph D. Daley
Kevin E. Redinger
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Babcock and Wilcox Co
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Babcock and Wilcox Co
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Filing date
Publication date
Application filed by Babcock and Wilcox Co filed Critical Babcock and Wilcox Co
Publication of EP0201338A2 publication Critical patent/EP0201338A2/fr
Publication of EP0201338A3 publication Critical patent/EP0201338A3/fr
Withdrawn legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/32—Liquid carbonaceous fuels consisting of coal-oil suspensions or aqueous emulsions or oil emulsions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
    • B03D1/00—Flotation
    • B03D1/02—Froth-flotation processes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03B—SEPARATING SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS
    • B03B9/00—General arrangement of separating plant, e.g. flow sheets
    • B03B9/005—General arrangement of separating plant, e.g. flow sheets specially adapted for coal
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/32—Liquid carbonaceous fuels consisting of coal-oil suspensions or aqueous emulsions or oil emulsions
    • C10L1/326—Coal-water suspensions

Definitions

  • the invention relates to a method and apparatus for producing coal-water fuel (CWF) on a commercial scale which uses a unique application of conventional, commercially available equipment.
  • CWF coal-water fuel
  • Individual unit operations in the invention include coal crushing, rod milling, sieve bend screening, froth flotation, vacuum filtration, refuse dewatering, and ball milling. These have been practiced in the coal preparation and minerals beneficiation industries for many years.
  • the invention also uses a reverse flotation operation.
  • the size reduction unit operations; crushing, rod milling, and ball milling, are common in mineral processing plants, e.g. copper and molybdenum ore concentration operations. Rod and ball milling are not found in conventional coal beneficiation operations. Current practice is to avoid the production of fine coal, primarily because of the inefficiency of conventional fine coal cleaning operations.
  • Froth flotation is a commercially proven technique for reducing, the ash content of feed coal.
  • most conventional coal flotation applications only ten to twenty percent of the total plant feed is passed through the flotation circuit.
  • the entire feed stream may be directed to the flotation circuit depending on coal characteristics.
  • Separation of the flotation feed into coarse and fine streams (split feed) has been demonstrated to improve the performance of the flotation circuit.
  • Several commercial operations do practice split feed flotation, but this is not common. Separate flotation of coarse coal was first performed about 1960 at the pipeline plant of Hanna Coal Company in Cadiz, Ohio.
  • the Kerr McGee Company has also installed split feed flotation for processing 0.589mm (28 mesh) x 0 raw coal in their newest 1200 TPH preparation plant-Multiple stage or "rougher-cleaner" flotation has been practiced in the coal industry for over 20 years.
  • the first rougher-cleaner circuits in the coal industry in the United States were designed and installed in 1963 at three plants of Bethlehem Mines Corporation in Washington County, Pennsylvania.
  • the rougher-cleaner flotation circuits were designed for 60 TPH of 0.589mm (28 mesh) x 0 coal.
  • a method of producing coal-water fuel from raw coal characterised by the steps of:- breaking up the raw coal to form liberated granular coal;
  • apparatus for producing coal-water fuel from raw coal characterised by:- a crusher for receiving the raw coal and crushing it;
  • the invention is thus drawn to a method and apparatus for the production of coal-water fuel (CWF) on a commercial scale and using a unique combination of unit operations which, in and of themselves, are conventional.
  • the individual unit operations include coal crushing, rod milling, sieve bend screening, froth flotation, vacuum filtration, refuse dewatering, and ball milling, as well as a reverese flotation operation.
  • the operations include the production of fine particles through staged size reduction in the rod and ball mill circuits which is not a common practice in the coal industry. Neither is the complexity in scope of the froth flotation circuit found in this industry.
  • the beneficiation circuit is also positioned between the size reduction devices.
  • Integration of a coal beneficiation circuit in the inventive process provides the capability of reducing the ash and sulphur content of the raw coal. This capability expands the potential supply of acceptable raw coal feedstocks and provides for the possibility of supplying various quality fuels to meet specific customer requirements.
  • the process extends the commonly accepted limitations of conventional coal beneficiation operations. This is possible because the fine grinding required for CWF production also results in liberation of undesirable mineral matter and pyritic sulphur from the raw coal. Production of a coal-water fuel also eliminates the need for thermal drying of the ground coal and the subsequent handling and storage problems associated with fine, dry coal.
  • the invention can provide a method and arrangement of existing apparatus for producing a coal-water fuel comprising a crushing and primary grinding step and equipment for liberating undesirable components of the coal, a conventional froth flotation step and equipment for pyrite removal, a dewatering step and equipment for concentrating the solids content, a slurry preparation step and equipment for controlling particle size distribution and a refuse dewatering and water clarification step and equipment. While the individual function circuits remain constant in the various embodiments of the invention, individual items of the equipment can be substituted. Thus in an operating plant, parallel equipment would be installed and process piping arranged so that individual units could be by-passed in the event of equipment failure or for alternative product preparation.
  • the apparatus shown in Figure 1 is producing coal-water fuel and comprises six functional circuits. These are a crushing and primary grinding circuit generally designated 2, a froth flotation circuit for ash and pyritic sulphur reduction designated 4, a product dewatering circuit designated 6 for establishing a selected solids content, a slurry preparation circuit designated 8 for producing a desirable particle size distribution in the fuel, and a refuse dewatering and water clarification circuit designated 10 for treating refuse from one or more of the other functional circuits and for clarifying water from those circuits and for reuse in the CWF production process.
  • a crushing and primary grinding circuit generally designated 2
  • a froth flotation circuit for ash and pyritic sulphur reduction designated 4 for establishing a selected solids content
  • a slurry preparation circuit designated 8 for producing a desirable particle size distribution in the fuel
  • a refuse dewatering and water clarification circuit designated 10 for treating refuse from one or more of the other functional circuits and for clarifying water from those circuits and for reuse in the CWF production process
  • Figure 2 shows another embodiment of the invention with a crushing circuit 22, a froth flotation circuit 24, a reverse flotation circuit 26, a dewatering circuit 28, a slurry preparation circuit 30 and a refuse treatment circuit 32.
  • Raw coal arriving at a plant is sampled and stored in separate piles (not shown) if desired. Coal would be moved from the piles to one of several raw coal storage bins one of which is shown at 202 in Figure 2. Separate feeders on each bin would permit blending of coals ahead of the process to meet specific feed requirements.
  • the crushed coal flows by gravity to the primary wet grinding operation at 106.
  • This wet grinding operation serves several important functions: (1) it ensures a consistent coal particle size distribution to downstream processes independent of the raw coal size distribution, (2) it creates highly active, freshly ground coal surface sites for subsequent froth flotation processing, (3) it inhibits surface oxidation of the newly produced active coal sites, and (4) it acts as an efficient wetting/mixing/conditioning device.
  • the first ( Figure 2) is a conventional closed circuit wet ball milling process.
  • the mill product is pumped to a hydrocyclone classifier 208.
  • the sieve bend overproduct is returned to the mill 206 for regrinding, and the pyrite enriched underproduct is directed to a refuse thickener 284 in the circuit 32.
  • Cyclone overflow is directed to the froth flotation circuit 24. This type of circuit may be useful for coals containing a relatively high. amount of coarse pyrite contamination.
  • Open circuit rod milling is a second alternative (not shown).
  • the rod mill alternative would be expected to provide a narrower size distribution, i.e. fewer ultrafine particles, while still producing the minus 0.589mm (28 mesh) product. Reducing the amount of ultrafine particles should improve the performance of the froth flotation circuit.
  • the minus 0.589mm (28 mesh) product from the grinding circuit 22 may be directed to either the froth flotation circuits 24, 26, forming a beneficiation circuit, or possibly to a vacuum filtration system 229 for dewatering in circuit 28 as feed to the slurry preparation circuit 30.
  • the latter option will be used if the coal is of sufficient quality to meet customer specifications without further ash or sulphur reduction. This option may be used if a pre-cleaned coal is chosen for feed to the process.
  • the performance of the flotation process is dependent to some extent on the distribution of particle sizes present in the feed, as are all beneficiation techniques. Flotation kinetics and optimal cell operating conditions are particle size dependent. Therefore, close control of particle size may be required to improve selectivity and, hence, ash rejection and coal recovery.
  • the flotation feed may be split into coarse and fine fractions depending on the characteristics of the coal being processed. This choice involves determination of the feed size distribution, to predict the mass flows to each circuit, and analysis of the flotation behaviour of individual size fractions. Note that the grinding mill may be controlled to adjust the product size distribution.
  • the grinding circuit product can be classified using a two-stage sieve bend arrangement 212.
  • the first stage sieve bend is designed to separate the feed stream into 0.589 x 0.295 mm (28 x 48 mesh) at 214 or 0.589 x 0.208mm (28 x 65 mesh) and minus 0.295mm (48 mesh) or minus 0.208mm (65 mesh) products at 216,.
  • the actual size differentiation will be determined by the characteristics of the coal being processed. Screening inefficiencies will result in some carry-over of fine material with the sieve bend overproduct.
  • This overproduct can be passed over a second sieve bend (not shown, but again designed for a 0.295 or 0.208mm (48 or 65 mesh) cut to improve removal of the fine material. Water sprays are needed on this second sieve bend to improve screening efficiency. The coarse and fine fractions are collected in separate sumps for pumping to the appropriate multistage flotation circuit.
  • Multistage flotation involves retreating the froth product for further ash and sulphur reduction.
  • at least one flotation stage 218-223 would be necessary.
  • the actual number of stages required depends on the measured froth product quality and characteristics of the coal being processed. Generally, each successive stage is operated to provide an increasingly higher quality product. Physically, the stages are located at different levels in the plant so that the froth product from one stage may be gravity fed to the next. Note that no recycling of the high ash, high sulphur tailings products is intended. These products are directed to the refuse dewatering and water clarification circuit 32 (dash lines).
  • Each stage comprises one or more individual flotation cells.
  • the froth from each cell may be collected separately so that product quality can be closely monitored and controlled. If necessary, the froth may be sprayed with water to remove any loosely held middlings particles.
  • Flotation reagents will be added directly to the flotation cells or to a conditioning tank ahead of the cells.
  • An alcohol or glycol frother such as methyl amyl alcohol (or methy isobutyl carbinol), will be used to produce a selective, stable froth.
  • fuel oil No. 2 or No. 6
  • alternative flotation promoters will be added to improve coal recovery.
  • the actual reagent package required will be coal specific and must be identified by laboratory research for each appliction of the process.
  • Separation of the grinding circuit product into coarse and fine streams may or may not be required, depending on the characteristics of the coal being processed.
  • the froth products from these cells may or may not require retreatment in the cleaner stage 219. Additionally, chemical reagents may be added to the remainder of the rougher cells to float as much material as possible. These froth products may be directed to coarse-cleaner flotation 219. The quality of the froth product from the last rougher cell may be substantially lower than that from previous cells. This low grade middlings product may be passed over a sieve bend, (not shown in the Figure) with the overproduct returned to the crushing circuit 22 for regrinding and the underproduct directed to the refuse dewatering circuit 32.
  • the appropriate froths from the rougher stage 218 may be fed to the cleaner stage 219. Water is added to the rougher cell froth launders 218 to dilute the feed to the cleaner stage 219 to approximately 10% solids by weight. the purpose of this stage is to produce a final clean coal product in terms of ash and sulphur content and carbon yield. Pyrite depressing reagents, such as CaO, KMnO 4 , or K 2 Cr 2 O 7 , may be added to the flotation cells to improve sulphur reduction. The coarse cleaner froth products flow to the vacuum filter feed sump 228. As in the rougher stage, the froth from the last cell may need to be screened and returned to the grinding mill 206. The cleaner tailings are directed to the refuse dewatering circuit 32.
  • the underflow from the classification of the grinding circuit product on line 216 (typically 0.295mm (48 mesh) x 0 or 0.208mm (65 mesh) x 0) flows directly to the fine coal rougher flotation feed sump.
  • the feed solids content of the fine coal rougher circuit 221 is less than that of the coarse rougher 218, probably on the order of 5 to 7% solids. This lower solids content is a result of most of the water from the grinding circuit product (at 50% solids) passing through the sieve bend 212 with the fine coal. It would be impractical to include a dewatering device at this location in the process. Therefore, the fine coal rougher flotation unit 221 must handle all of this water.
  • the dilute feed is beneficial to flotation performance, but may increase the size or number of flotation cells required.
  • the froth products from all of the fine rougher cells 221 may be cleaned at 222 and then recleaned at 223 at about 10% solids by weight to remove ash and as much sulphur as possible.
  • the actual number of flotation stages will be dependent on the characteristics of the coal being processed. The sulphur reduction at this point will essentially be limited to particle sizes between 48 and 150 mesh.
  • the tailings from all of the stages are directed to the refuse disposal and water treatment circuit - 32 for dewatering and water clarification.
  • the reverse flotation circuit 26 is operated to reject fine pyritic sulphur and maximize fine coal recovery. Reverse flotation is not applicable for ash reduction, nor is it efficient for separation of plus 0.147mm (100 mesh) pyrite. Consequently, the reverse flotation circuit must be preceded by conventional coal flotation in circuit 24.
  • the inventive process includes a two-stage 226, 227 reverse flotation circuit for reducing the sulphur content of the fine coal froth.
  • This froth product at 20% to 25% solids by weight, must be conditioned to prepare the particle surfaces for coal depression and pyrite flotation.
  • the actual reagents and reagent quantities used are characteristic of the particular coal being processed. Additionally, the tank contents must be adjusted to a pH of 4. This acidic condition helps to remove certain chemical groups from the pyrite particle surfaces rendering them more hydrophobic. Dilution to 15% to 20% solids may be required prior to feeding this conditioned slurry to the rougher reverse flotation unit 226.
  • the rougher reverse flotation stage 226 produces a high sulphur froth and a corresponding low sulphur clean coal tailings product.
  • the reverse flotation rougher tails are directed to the clean coal dewatering circuit 28.
  • the froth from the last few cells in the rougher unit 226 may contain excessive amounts of carbon. To recover this carbon, the rougher froth will be retreated in a cleaner stage 227.
  • the high sulphur froth product from the reverse flotation cleaner stage 227 may be passed over a sieve bend to (not shown) remove coarse coal/pyrite particles containing a significant amount of carbon.
  • the overproduct would then be directed to the crushing circuit 22 for regrinding and liberation of the pyrite particles.
  • the sieve bend underproduct would flow to the refuse disposal and water treatment circuit 32 for dewatering and water clarification.
  • the reverse flotation cleaner tails may be considered a coal middlings product which can be returned to the reverse flotation rougher feed 226. This product could also be sent back to the crushing circuit 22 for regrinding.
  • the clean coal dewatering circuit 28 must be designed to provide a closely controlled, high solids content feed to the slurry preparation circuit 30.
  • the approximately 25%. solids feed to the disc filter 229 must be dewatered to approximately 75% to 78% solids.
  • This feed is comprised of the conventional coal flotation froth products and the reverse flotation tailings products. Should the beneficiation circuits 24 and 26 be by-passed, , the crushing circuit 22 product will be sent directly to the disc filter feed sump 228.
  • the filter feed sump 228 serves as a storage and mix tank for the filter feed. Laboratory experience indicates that the froth from the flotation circuit 24 products should break up fairly easily under mild agitation. A consistent filter feed at maximum solids concentration aids filter performance.
  • a filter vacuum must be mainained at a constant, high level. Dual-stage vacuum pumps are required to maintain vacuum with ground coals of varying filter cake porosity. A second means of maintaining a high vacuum is to ensure that the filter tub remains full. Filter rotation speed and, hence, production of filter cake, is controlled to match the tonnage of clean coal product from the froth flotation circuits. However, coal flotation products would be pumped to the filter at a rate higher than the operating filter capacity so that a steady overflow back to the filter feed sump 228 is provided. This overflow results in a constant flotation product level in the filter tub of the vacuum disc filter 229. A snap blow feature should be included for a good cake discharge.
  • the importance of the dewatering circuit 28 to coal-water fuel production cannot be overemphasized.
  • the solids content of the dewatered product must be kept as high as possible to provide some degree of flexibility in the subsequent slurry production circuit 30.
  • the slurry preparation circuit 30 consists of a second grinding step at 230 to produce the optimal particle size distribution. Slurry rheology is controlled in two sets of high sheer mixer tanks 232 in series; the first for viscosity control, the second for controlling slurry stability. Note that the slurry preparation system 30, like the flotation systems 24 and 26, includes the necessary chemical handling, storage and metering equipment (not shown).
  • the dewatered, clean coal filter cake from the vacuum disc filter 229 falls directly onto a belt conveyor through plastic lined chutes. Conveyor belt scales are used to provide an accurate measurement of the feed rate to the grinding mill 230.
  • the cake drops into a ball mill screw feeder where a portion of the chemical dispersant reagent, pH adjustment chemicals, and any required dilution water will also be added (dotted line).
  • the regrind ball mill 230 is operated in a high solids mode (70% to 78% solids by weight). Consistent control of the product particle size distribution is achieved by controlling the viscosity of the mill coal-water slurry via the addition of chemical based dispersants.
  • the regrind ball mill operating variables, including ball size distribution, ball charge loading, and mill speed, are chosen to maximize product throughput and minimize power consumption. since the ball mill is a very efficient mixer, the need for sophisticated solids takedown mechanical mixers is eliminated.
  • the semi-finished coal-water slurry from the mill will have a viscosity ranging from 1.5 to 4 Pa.S (1500 to 4000 centipoise) and a solids content of 70% to 75%.
  • This slurry is pumped to a viscosity process blend tank (not shown) equipped with low speed, high efficiency impeller mixers where the remaining chemical based dispersants are added to lower the slurry viscosity to approximately 0.5 to 2 Pa.S (500 to 2000 centipoise).
  • the product from the viscosity process blend tank (not shown) is pumped to a high frequency vibrating screen 231 for removal of oversize material 0.295mm (+48 mesh particles).
  • the amount of oversize material is projected to be less than 3% by weight and will be recycled to the ball mill 230 feed fro additional grinding.
  • This vibrating screen is an external classifier which forms a closed grinding circuit to provide control of the maximum particle size.
  • the vibrating screen 231 underflow will flow by gravity to a stabilizer process blend tank 232 for final slurry preparation.
  • a chemical stabilizer to inhibit particle settling and caustic chemical for pH adjustment may be added to the blend tank to obtain final product quality. All of the chemicals used in slurry preparation are commercially available, environmentally acceptable, and can be readily obtained from existing chemical suppliers.
  • the final coal-water fuel (CWF) product at 240 is pumped from the stabilizer process blend tank to storage tanks. These storage tanks are insulated and equipped with mixers to ensure product homogeneity. The product can be transferred from the storage tanks for shipment by tanker truck, rail or barge.
  • the refuse dewatering and water clarification circuit 32 is designed to prepare the plant refuse for environmentally acceptable disposal and to provide clean process water for reuse in the plant. Any contamination of recirculating water can adversely affect product quality. Therefore, proper performance of this system must be ensured to maintain overall process performance and product quality.
  • All of the process rejects including tailings from the conventional froth flotation circuits 24, froth from the rougher reverse flotation operation 26, and filtrate from the vacuum disc filter 229, flow by gravity to a static thickener 284.
  • the thickener provides a fairly quiescent environment in which solid particles may settle out, leaving a clarified water layer. This thickener overflow is returned to the plant water supply system for recycling to the process. Fresh makeup water must also be added to the water supply system.
  • Thickener underflow at approximately 25% to 30% solids by weight, is pumped to a belt filter press 286 for further dewatering.
  • the belt filter press was selected because of its ability to handle ultra fines and clay slimes.
  • the belt press filtrate is returned to the static thickener 284.
  • the dewatered refuse filter cake 60% to 80% solids by weight, is transferred to an external storage pile by a belt conveyor for subsequent landfill disposal.
  • the ponds To protect the CWF production process against shutdown in the event of an upset in any portion of the refuse dewatering and water clarification circuit, several ponds will be constructed at the plant site.
  • the ponds also provide storage for excess plant water, supply process makeup water on a continuing or intermittent basis, and provide a receiving basin for thickener drainage during schedule and unscheduled plant shutdowns.
  • the inventive process offers several advantages for both slurry production and coal beneficiation. These advantages may be broadly categorized as resulting from the modular design or attributed to operating flexibility.
  • the invention evolved through consideration of distinct unit operations to address specific functional needs such as ash and pyritic sulphur liberation, ash reduction, pyritic sulphur removal, dewatering, and slurry preparation. This approach resulted in a modular structure which should permit:
  • the invention has been designed to permit a high degree of operating flexibility to respond to variations in feed coal quality and customer product specifications. a few examples of flexibility include:
  • the inventive CWF production process is unique in that it specifically addresses the problem of fine particle pyritic sulphur removal.
  • the degree of primary grinding required for liberation of the mineral matter and pyritic sulphur contaminants from the coal matrix is dependent on the nature and distribution of these contaminants.
  • the contaminants in the Pittsburgh seam coal are more finely disseminated than those charactertistic of the Upper Freeport seam coal. Therefore, the Pittsburgh seam coal must be ground finer to attain the desired liberation.
  • the size distribution of the final coal-water fuel product represents a limit to the amount of grinding permitted at this stage. Flotation feed particle size distributions produced by rod milling in the laboratory are presented in Figure 3 and Figure 4.
  • the froth flotation circuits examined included multiple stage coal flotation and reverse flotation. Significant reductions in the ash and sulphur contents of the feed were achieved with high recoveries of the combustible material as shown in the following table.
  • the froth products from the flotation testing were dewatered using a filter leaf test kit. A range of filtration cycle characteristics and vacuum pressures were investigaged. The tests indicated that dewatered cake solids contents ranging from 68% to 77% solids could be obtained from the fine particle flotation products.
  • the dewatered froth products were mixed with chemical reagents and ground in a laboratory batch ball mill to produce stable coal water slurries.
  • the slurry characteristics are indicated in the following table:

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  • Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Liquid Carbonaceous Fuels (AREA)
  • Solid Fuels And Fuel-Associated Substances (AREA)
  • Separation Of Solids By Using Liquids Or Pneumatic Power (AREA)
  • Crushing And Grinding (AREA)
  • Processing Of Solid Wastes (AREA)
EP86303504A 1985-05-10 1986-05-08 Production d'un combustible charbon-eau Withdrawn EP0201338A3 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US73255085A 1985-05-10 1985-05-10
US732550 1985-05-10

Publications (2)

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EP0201338A2 true EP0201338A2 (fr) 1986-11-12
EP0201338A3 EP0201338A3 (fr) 1987-11-11

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EP (1) EP0201338A3 (fr)
JP (1) JPS61261395A (fr)
KR (1) KR930011073B1 (fr)
CN (1) CN86103216A (fr)
AU (1) AU5717786A (fr)
BR (1) BR8602037A (fr)
CA (1) CA1297674C (fr)
ES (2) ES8705912A1 (fr)
IL (1) IL78789A (fr)
IN (1) IN165645B (fr)
ZA (1) ZA863374B (fr)

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CN108001744A (zh) * 2017-12-21 2018-05-08 山东金朗生物科技有限公司 右旋糖酐生物大分子成品自动收集粉碎包装系统及方法

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CN101734809B (zh) * 2009-12-18 2012-02-01 吴爱华 高效低能耗的尾矿干排工艺
CN103952206A (zh) * 2014-05-14 2014-07-30 许宁 一种固态燃料燃烧前的降灰脱硫方法
CN105665124B (zh) * 2016-04-13 2019-05-28 中国矿业大学 高连生体高灰高硫煤分选制浆一体化工艺
CN107267236A (zh) * 2017-06-27 2017-10-20 深圳瑞科天启科技有限公司 一种利用煤或煤矸石生产高热值水煤浆的工艺及采用该工艺的煤气化工艺

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Cited By (5)

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Publication number Priority date Publication date Assignee Title
WO2009016668A2 (fr) 2007-08-02 2009-02-05 Mario Mazza Procédé de traitement de charbon avec une teneur élevée en impuretés pour obtenir un mélange combustible purifié utilisable à la place du mazout dans les centrales électriques actuelles
WO2009016668A3 (fr) * 2007-08-02 2009-07-16 Mario Mazza Procédé de traitement de charbon avec une teneur élevée en impuretés pour obtenir un mélange combustible purifié utilisable à la place du mazout dans les centrales électriques actuelles
US20100187090A1 (en) * 2007-08-02 2010-07-29 Mario Mazza Method for processing coal with a high content of impurities to obtain a purified fuel mixture utilizable in place of fuel oil in present-day power plants
CN108001744A (zh) * 2017-12-21 2018-05-08 山东金朗生物科技有限公司 右旋糖酐生物大分子成品自动收集粉碎包装系统及方法
CN108001744B (zh) * 2017-12-21 2024-04-30 山东金洋药业有限公司 右旋糖酐生物大分子成品自动收集粉碎包装系统及方法

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IL78789A0 (en) 1986-08-31
IL78789A (en) 1990-04-29
ES8705912A1 (es) 1987-05-16
ES8800076A1 (es) 1987-10-16
KR860009106A (ko) 1986-12-20
JPH0412911B2 (fr) 1992-03-06
KR930011073B1 (ko) 1993-11-20
IN165645B (fr) 1989-12-02
ES557422A0 (es) 1987-10-16
JPS61261395A (ja) 1986-11-19
CN86103216A (zh) 1986-12-17
BR8602037A (pt) 1987-01-06
CA1297674C (fr) 1992-03-24
EP0201338A3 (fr) 1987-11-11
ES554805A0 (es) 1987-05-16
AU5717786A (en) 1986-11-13
ZA863374B (en) 1987-05-27

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