The technique that a kind of coal preparation plant's thickener underflow directly prepares water-coal-slurry
Technical field
The present invention relates to the technique that a kind of coal preparation plant's thickener underflow directly prepares water-coal-slurry, belong to coal preparation with
Clean utilization field.
Background technology
Coal washing is not only currently to improve the effective important method of Coal Quality, and is to reduce pollution that caused by coal burning,
Improve the ecological environment most economical effective technological approaches.Floating tail-coal(Coal slime)It is the principal by product of coal preparation plant, there is moisture
The features such as content is high, fine size, and fraction of particle is more, and ash content is high and viscosity is big, inconvenience is brought to comprehensive utilization.With ring
The raising of consciousness and Coal Quality requirement is protected, slurry of coal washing plant often occurs unsalable.According to statistics, current national coal slime annual emissions
It more than 200,000,000 tons, but because its moisture is high, can not directly utilize, and meet current and lose, air-dry and fly upward, transport difficult, cause to select
Coal works overwhelming majority coal slime is stacked on the spot.Coal slime bulk deposition not only waste of resource, environment is polluted, can also have a strong impact on coal washery
Normal production.Therefore, the processing of coal slime and problem of complex utilization are urgently to be resolved hurrily.
At present, the utilization ways of coal slime mainly include:Coal combustion generates electricity, coal mud water slurry technology, slime briquette technology
Etc., wherein coal mud water slurry technology is widely adopted, and achieves preferable effect.However, current coal mud water slurry
Technology is generally using the technological process shown in Fig. 1:Floating tail-coal first passes around coal preparation plant's thickener concentration, thickener underflow
Slime filter cake is obtained after filter press is further dehydrated, then using slime filter cake as raw material, is prepared using the processes such as stirring are sized mixing
Water-coal-slurry.In this technical process, because cohesive force is big between coal slime particle, the easy plate of the filter cake that coal slime raw material is formed after press filtration
Form block, therefore often needed using equipment strong stirrings such as mixers in follow-up water-coal-slurry preparation process(Sometimes even also need to
Broken and powder-grinding process)To disperse slime filter cake, to prepare even particle size distribution, slurry performance is stable, disclosure satisfy that defeated
Send the water-coal-slurry product with requirement.
Such as document 1(The clay standby water-coal-slurry experimental study of low grey high combustion value coal, clean coal technology, 2009,16(2):45-
48)Need to carry out grinding to coal slime using processes such as crushing, rod millings;Patent(Application number:200710015400.X)There is provided
Coal mud water slurry productive technology needs to carry out grinding to coal slime using ball mill and intense stirring device and disperseed, to prepare
The preferable water-coal-slurry of paste-forming properties;And patent(Application number:200810095266.3)What is provided uses primary slime and sulfomethylated lignin
Sour sodium powder prepares water-coal-slurry and then pinches mud mixer to primary slime using twin shaft(Dry powder)Carry out after disperseing, then pass through strong stirring
Device carries out twice dispersing processing to its slurry.Obviously, the preparation technology of above-mentioned coal mud water slurry is relatively complicated, and runs
Equipment is more, and input is big, substantially increases the production cost of water-coal-slurry.
On the other hand, 65% or so is typically about according to the requirement of water-coal-slurry mobility and stability, the concentration of water-coal-slurry,
And the general moisture content of coal slime after press filtration is about 20-30%, water-coal-slurry flow difficulties are directly used as, it is defeated to be very easy to blocking
Pipeline is sent, therefore is required in later stage coal mud water slurry preparation process plus substantial amounts of water and a small amount of(About 1%)Dispersant and stabilizer
(As shown in Figure 1), slurry is uniform to be formed, and the water-coal-slurry with preferable mobility and stability.And in floating tail-coal
In processing procedure, thickener underflow is precisely in order to remove most moisture in coal slime, if therefore directly through press filtration operation
Coal mud water slurry is prepared using thickener underflow, can not only reduce the press filtration process in floating tail-coal processing procedure, is simplified
Tail coal handling process, reduce production cost, and can reduce using after press filtration coal slime prepare water-coal-slurry during because of filter cake group
Coalesce and disperse difficulty caused by block, reduce stirring(Even broken, grinding)The abrasion of equipment, and then simplify coal mud water slurry
Preparation technology.
In addition, for ease of the rapid subsidence of floating tail-coal, coal preparation plant often adds a certain amount of flocculant to add in thickener
The sedimentation of fast coal slime is excluded together with water it in follow-up filter-press dehydration process with improving thickening efficiency, but this part medicine
Agent has good facilitation in water-coal-slurry preparation process to the stability for improving water-coal-slurry.Therefore, according to thickener
Underflow effectively can also improve water-coal-slurry product to prepare water-coal-slurry using the flocculant added during coal slime concentration and settlement
Stability, so as to reduce production cost.
The content of the invention
The purpose of the present invention is exactly first through filter-press dehydration and after for coal slime in existing coal mud water slurry productive technology
Continuous pulping process, which adds a large amount of water, to be disperseed, complex process, and slime filter cake is easily reunited blocking after high energy consumption and press filtration
Cause the problems such as flocculant does not make full use of in difficulties in dispersion, thickener, propose a kind of coal preparation plant's thickener underflow without
Filter-press dehydration and be used directly to prepare water-coal-slurry technique.The present invention is thickener bottom after the concentrated machine of floating tail-coal is concentrated
Stream is handled without filter-press dehydration, and is sent directly into hydrocyclone and is carried out classification processing, and qualified thin material is delivered to coal slurry and stirred
Mix bucket and dispersant, stabilizer and fine coal powder(Sulphur-fixing agent can be also added if necessary)It is well mixed to prepare water-coal-slurry, and for attached
Near Industrial Stoves burning, thick material are then again introduced into hydraulic classiciation system after wet ball mill fine grinding.The present invention is not only
The handling process of floating tail-coal in existing coal preparation plant can be simplified, reduce the production cost of coal mud water slurry, and can be effective
Solves the problems such as occupation of land and environmental pollution that coal preparation plant brings because coal slime is stacked;The final high value added utilization for realizing coal slime,
Increase the economic benefit of enterprise.
The purpose of the present invention can be realized by following technique measures.
The technique that a kind of coal preparation plant's thickener underflow provided by the present invention directly prepares water-coal-slurry mainly includes raw material standard
Standby, water-coal-slurry modulation and finished product conveying three-procedure, are comprised the following steps that:
A, raw material prepares:By floating tail-coal after thickener concentrates, overflow enters coal preparation plant's circulation circulation profit
With its underflow is then sent directly into hydrocyclone group by Pulp pump I and carries out high-effective classifying;After classification is handled, granularity is less than
75 μm of qualified material is directly entered coal slurry agitator by overfall, and granularity is more than 75 μm of thick materials then via hydrocyclone
Group underflow sand removing hole is sent into wet ball mill and carries out fine grinding;Slurry after fine grinding by Pulp pump II return hydrocyclone group with
The raw material mixing that Pulp pump I conveys carries out classification again and handled, so that can meet into the material in coal slurry agitator
Water-coal-slurry granularity requirements, be advantageous to improve the stability of follow-up water-coal-slurry finished product, to ensure that the material into coal slurry agitator is expired
Sufficient water-coal-slurry granularity requirements, effectively avoid " running thick " phenomenon.
B, water-coal-slurry is modulated:In coal slurry agitator, according to the inlet amount and water of qualified material in step a in the unit interval
The quality requirement of coal slurry, the dispersant and stabilizer medicament of water-coal-slurry total amount 0.6 ~ 1.0% are added using automatic medicine adding apparatus, and
Fine coal powder is incorporated, wherein, the allocation ratio X of fine coal powder is according to formula:X=(M1C1-M2C2)/M1Calculate, wherein M1Produced for water-coal-slurry
The total amount of product, C1For the concentration requirement of water-coal-slurry product, M2For the inlet amount of qualified material, C2For the solid concentration of qualified material;
In water-coal-slurry modulated process, the incorporation by regulating and controlling fine coal powder can effectively adjust water coal slurry concentration and final water-coal-slurry product
Caloric value;After above-mentioned material and well mixed additive, slurry is sent into mechanical stirring device by Pulp pump III
It is standby in slurry can.
C, finished product conveys:The water-coal-slurry finished product in slurry can is delivered in Industrial Stoves using high speed shear pump and efficiently fired
Burn, the high speed shearing emulsification effect of shear pump can further improve the uniformity and stability of water-coal-slurry, after being advantageous to
Continuous conveying and burning.
Concentration of solid particles is 40 ~ 60% in underflow described in step a of the present invention;Dispersant described in step b is polycarboxylic-acid
Composite dispersing agent, stabilizer are Polyacrylamide stabilizer;The mass ratio of the dispersant and stabilizer is 1 ~ 4: 1.
Compared with existing coal mud water slurry productive technology, beneficial effects of the present invention are as follows:
(1)Thickener underflow without filter-press dehydration handle is directly used as prepare water-coal-slurry, can not only eliminate coal slime because
Press filtration and caused reunion caking phenomenon, reduce the energy expenditure and equipment in follow-up coal mud water slurry preparation process(Such as stirring
Machine or broken, grinding machine)Abrasion;And the handling process of floating tail-coal can be simplified, substantially reduce the operation of coal preparation plant into
This.
(2)The flocculant for making full use of the floating agent contained in thickener underflow and tail coal concentration process to add, suitably
The dispersiveness and stability of adjustment water-coal-slurry can produce the coal mud water slurry with good paste-forming properties, greatly reduce water-coal-slurry
The dosage of additive, effectively reduce the production cost of coal mud water slurry.
(3)According to user to caloric value and the requirement of pollutant emission, regulation can be passed through in water-coal-slurry modulated process
The combustion heat value and Pollutant emission concentration of the incorporation appropriate regulation water-coal-slurry product of fine coal powder and sulphur-fixing agent, entirely produce work
Skill strong adaptability, the controlling of quality of water-coal-slurry product is easy, can meet the needs of different user.
Brief description of the drawings
Fig. 1 is the coal mud water slurry preparation technology flow of prior art.
Fig. 2 is the process chart of the present invention.
Sequence number in accompanying drawing:1st, thickener, 2, Pulp pump I, 3, hydrocyclone group, 4, wet ball mill, 5, Pulp pump II,
6th, coal slurry agitator, 7, cleaned coal powder cabin, 8, belted electronic balance, 9, automatic medicine adding apparatus, 10, Pulp pump III, 11, slurry can, 12,
High speed shear pump, 13, Industrial Stoves.
Embodiment
The present invention is below with reference to embodiment(Fig. 2)It is described in further detail:
Embodiment 1
The invention will be further described by taking Shenhua Group coal preparation plant thickener underflow as an example:
The floating tail-coal of Shenhua Group coal preparation plant belongs to low grey coal slime, and content of ashes is about 30%, and caloric value is
13.5MJ/kg.After the concentrated machine 1 of coal preparation plant's floating tail-coal concentrates, overflow returns to coal preparation plant's circulation and utilized, its underflow
(Concentration of solid particles is about 50%, and microfine of the granularity less than 75 μm accounts for the 82% of solid amount in solid particle)Via slurry
Pump I 2 is sent directly into hydrocyclone group 3 and carries out high-effective classifying.After classification is handled, granularity is less than 75 μ in hydrocyclone group 3
M qualified material(Account for the 82% of solid amount, it is assumed that thickener underflow is classified completely)Coal slurry stirring is directly entered by overfall
Bucket 6, and granularity is more than 75 μm of thick materials(Account for the 18% of solid amount)Then it is sent into via the underflow sand removing hole of hydrocyclone group 3
Wet ball mill 4 carries out fine grinding.Slurry after fine grinding returns to hydrocyclone group 3 by Pulp pump II 5 and conveyed with Pulp pump I 2
Raw material mixing carry out again classification handle.
In the coal slurry agitator 6 with high-speed rotating impeller, according to qualified material 24.6m3/ h inlet amount(Assuming that water
The specified disposal ability of power cyclone group is 30m3/ h, 82% qualified material all enter coal slurry agitator 6, and its by overfall
Concentration is identical with feed thickness)With the quality requirement of water-coal-slurry(The solid concentration requirement of water-coal-slurry is 66%), essence in the unit interval
Coal dust addition M can then pass through formula:(M+24.6m3/h×1500kg/m3)×66%-(24.6m3/h×1500kg/m3)×
50%=M is calculated.
24.6m in formula3/ h be coal slurry agitator 6 in unit interval feed volume, 1500kg/m3It is assumed that coal slurry stirs
The density fed in bucket 6, the inlet amount M of qualified material2For 24.6m3/h×1500kg/m3;66% is water-coal-slurry product requirement
Solid concentration C1, 50% is the solid concentration C of qualified material in coal slurry agitator 62。
By being calculated, the addition M of fine coal powder is about in the unit interval:17364.7kg/h and according to fine coal powder
Allocation ratio calculation formula X=(M1C1-M2C2)/M1, the allocation ratio X for calculating fine coal powder is about 32%(Water-coal-slurry total amount in formula
M1=M+M2=17364.7kg/h +24.6m3/h×1500kg/m3=54264.7kg/h, is calculated with the unit interval, and dispersant with
The quality of stabilizer is ignored).
Uniformly added into coal slurry agitator 6 via belted electronic balance 8 by cleaned coal powder cabin 7 a certain amount of(Pass through calculating
The addition of fine coal powder in the unit interval drawn)Fine coal powder(The control of fine coal powder delivery rate is 17364.7kg/h), and utilize
Automatic medicine adding apparatus 9 adds the polycarboxylic-acid composite dispersing agent and Polyacrylamide stabilizer of water-coal-slurry total amount 0.8% or so
(The ratio of dispersant and stabilizer is 1.5:1).After above-mentioned material and well mixed additive, it will be expected by Pulp pump III 10
Slurry is sent into standby in the slurry can 11 with mechanical stirring device.Finally, using high speed shear pump 12 by the water in slurry can 11
Coal slurry finished product, which is delivered in the Industrial Stoves 13 about outside 5km, to burn, and after testing, its caloric value is up to 11.12MJ/kg, and water coal
Starch mobility(Shear rate is 100s-1When, viscosity 948mPas)And have good stability, comply fully with national water-coal-slurry skill
Art standard(GB/T18855-2008), the combustion requirements of general industry kiln can be met.
Embodiment 2
The invention will be further described by taking Henan coal preparation plant of derived energy chemical group thickener underflow as an example:
The floating tail-coal of Henan coal preparation plant of derived energy chemical group belongs to middle grey coal slime, and content of ashes is about 40%, caloric value
For 12.1MJ/kg.After the concentrated machine 1 of coal preparation plant's floating tail-coal concentrates, overflow returns to coal preparation plant's circulation and utilized, its bottom
Stream(Concentration of solid particles is about 53%, and microfine of the granularity less than 75 μm accounts for the 78% of solid amount in solid particle)Via slag
Stock pump I 2 is sent directly into hydrocyclone group 3 and carries out high-effective classifying.After classification is handled, granularity is less than in hydrocyclone group 3
75 μm of qualified material(Account for the 78% of solid amount, it is assumed that thickener underflow is classified completely)Coal slurry is directly entered by overfall
Agitator 6, and granularity is more than 75 μm of thick materials(Account for the 22% of solid amount)Then via the underflow sand removing hole of hydrocyclone group 3
It is sent into wet ball mill 4 and carries out fine grinding.Slurry after fine grinding returns to hydrocyclone group 3 and Pulp pump I 2 by Pulp pump II 5
The raw material mixing of conveying carries out classification again and handled.
In the coal slurry agitator 6 with high-speed rotating impeller, according to qualified material 23.4m3/ h inlet amount(Assuming that water
The specified disposal ability of power cyclone group is 30m3/ h, 78% qualified material all enter coal slurry agitator 6, and its by overfall
Concentration is identical with feed thickness)With the quality requirement of water-coal-slurry(The solid concentration requirement of water-coal-slurry is 65%), essence in the unit interval
Coal dust addition M can then pass through formula:(M+23.4m3/h×1500kg/m3)×65%-(23.4m3/h×1500kg/m3)×
53%=M is calculated.
23.4m in formula3/ h be coal slurry agitator 6 in unit interval feed volume, 1500kg/m3It is assumed that coal slurry stirs
The density fed in bucket 6, the inlet amount M of qualified material2For 23.4m3/h×1500kg/m3;65% is water-coal-slurry product requirement
Solid concentration C1, 53% is the solid concentration C of qualified material in coal slurry agitator 62。
By being calculated, the addition M of fine coal powder is about in the unit interval:12034.3kg/h and according to fine coal powder
Allocation ratio calculation formula X=(M1C1-M2C2)/M1, the allocation ratio X for calculating fine coal powder is about 25.5%(Water-coal-slurry is total in formula
Measure M1=M+M2=12034.3kg/h +23.4m3/h×1500kg/m3=47134.3kg/h, is calculated with the unit interval, and dispersant
Ignored with the quality of stabilizer).
Uniformly added into coal slurry agitator 6 via belted electronic balance 8 by cleaned coal powder cabin 7 a certain amount of(By calculating
The addition of fine coal powder in the unit interval gone out)Fine coal powder(The control of fine coal powder delivery rate is 12034.3kg/h)With solid sulphur
Agent(Account for the 0.2% of water-coal-slurry total amount), and utilize the polycarboxylic-acid of the addition water-coal-slurry of automatic medicine adding apparatus 9 total amount 0.9% or so
Composite dispersing agent and Polyacrylamide stabilizer(The ratio of dispersant and stabilizer is 1:1).When above-mentioned material and additive
, will be standby in slurry can 11 of the slurry feeding with mechanical stirring device by Pulp pump III 10 after well mixed.Finally, utilize
Water-coal-slurry finished product in slurry can 11 is delivered in Industrial Stoves 13 by high speed shear pump 12 to burn, and after testing, its caloric value can
Up to 10.65MJ/kg, and water-coal-slurry mobility(Shear rate is 100s-1When, viscosity 748mPas)And have good stability, it is complete
Meet national COAL-WATER SLURRY TECHNOLOGY standard entirely(GB/T18855-2008), the combustion requirements of general industry kiln can be met.