CN1098127C - Deep physical coal deliming and desulphurizing technology - Google Patents

Abstract

The present invention discloses a physical depth ash desulfurizing coal preparation process for coal. The disseminated grain size of inorganic mineral substances in coal is very small so that low ash head coal can not be prepared by conventional coal preparation methods. In the process, depth pulverization is carried out for coal as raw materials by an energy saving stirring superfine grinding machine until organic combustible bodies are fully dissociated from inorganic mineral substances; low -ash and sulfur head coal grains in coal slurry after dissociation form flocs through emulsified non-polar oil and the action of high shearing and stirring of a floc generator, the flocs are separated by foam flotation, and the separated head coal flocs are dried and dehydrated by a filter press and molding heating power. Low ash and sulfur head coal products are finally obtained, and a process flow is illustrated in attached drawings.

Description

Deep physical coal deliming and desulphurizing technology

The present invention relates to a kind of coal physical method degree of depth deliming and desulphurizing coal preparation technique.

Because the disseminated grain size of inorganic mineral is very thin in the coal, Zhong Guo coking coal particularly, be difficult to therefrom to select ash content with the coal preparation method of routine and be lower than 6% low ash extract coal, even some coal can be selected this low ash extract coal with the high sink float of sharpness of separation, but its clean coal yield descends significantly, and is uneconomical.Be lower than 1% ultra clean coal and can't realize especially and will select ash content with physical method.In addition, the pyritous disseminated grain size in many kind coals also is very thin, and this pyrite is difficult to effectively remove with conventional coal preparation method equally.

For indivedual coals; after the ultra-fine grinding of raw coal process; can select ash content with the method for oil aggregation and be lower than 1% ultra clean coal; but because the oil consumption height can't be put to industrial production. the U.S. once used the bridging agent of pentane as the oil aggregation method, though can reduce the medicine consumption by reclaiming bridging agent, because the danger of potential blast; whole system must seal; and blanketing with inert gas, sorting cost height, its pilot scale line is removed.

Can produce ash content with chemical method and be lower than 1% ultra clean coal, but because of the need strong acid and strong base, cost height and contaminated environment also can't be applied to industrial production.

Describe the implementation of degree of depth deliming and desulphurizing task of the present invention in detail below in conjunction with accompanying drawing.For granularity greater than the feed coal of 2mm (as the gravity treatment cleaned coal, in the gravity treatment coal etc.), earlier through in small, broken bits to less than giving people's ultra-fine grinding mill behind the 2mm.If the granularity of feed coal can directly be given people's ultra-fine grinding mill less than 2mm (as floatation clean coal, floating tail-coal and sedimentation basin coal slime etc.).Organic flammable body and inorganic mineral that feed coal is milled in ultra-fine grinding mill wherein fully dissociate, again the product water behind the mill is made into the coal slurry that weight concentration is 5-10%, (0.5 kilogram-10 kilograms amount adds the non-polar oil through emulsification by feed coal per ton, if will select the cleaned coal of low sulphur content, then to add the pyrite inhibitor, in order further to reduce cleans ash, add dispersant to alleviate of the covering of high plaster pledge, coal slurry is given the floc sedimentation generator of people's high shear rate coal grain surface.Under the non-polar oil and high shear stirring action of emulsification, the purer coal particle through dissociateing relies on its natural hydrophobicity, overcomes the electrostatic repulsion between the coal grain and forms floc sedimentation, utilizes conventional froth flotation that floc sedimentation is sorted out from the grey tail coal of height then.Be provided with if in individual selected link, to satisfy the requirement of different final cleans ash.The cleaned coal of selecting takes shape in dry link again with the filter press dehydration in order further to reduce the moisture of cleaned coal, to have increased.

The technology of this invention is different from present froth flotation, oil aggregation choosing or selectivity floc sedimentation sorting process on separating mechanism.Though the dosage of conventional froth flotation is approaching with this technology, its can't sorting through the feed coal behind the ultra-fine mill.The oil aggregation choosing is that the cleaned coal particle of low ash forms closely knit little under the parcel of non-polar oil, and little granule is to use screen filtration with separating of the grey tail coal of height.Though this method can the fine beans of sorting, its dosage can't be accepted economically up to feed coal 20-50 kilogram per ton.The flocculant that selectivity wadding gang of bandits adopts is a macromolecule organic, big and loose many of the floc sedimentation that the floc sedimentation of its formation forms than technology of the present invention, so its mechanical entrapment to the grey tail coal of height is serious, sharpness of separation is low.

The present invention is the sorting process of inorganic mineral in a kind of deep removal coal, it is characterized in that: at first will fully dissociate feed coal ultra-fine grinding organic flammable body and inorganic mineral in the coal, the mean particle size D after the pulverizing [4.3] is 4 μ m-100 μ m.By adding the non-polar oil of emulsification, the non-polar oil consumption is feed coal 0.5kg-10kg per ton, and applies high shear forces, makes microfine low ash extract coal wherein form floc sedimentation, sub-elects the cleaned coal floc sedimentation with conventional froth flotation again.

Characteristics of the present invention are: 1. adopted low energy consumption to stir the ultra-fine feed coal that grinds of mill, inorganic mineral and the organic flammable body that embedding cloth is very thin in the feed coal fully dissociated.For

Select low grey low-sulfur cleaned coal and created condition; 2. utilize the natural hydrophobicity of coal to add the invigoration effect of non-polar oil, under the high shear stirring action, make the microfine cleaned coal particle of low grey low-sulfur

Form floc sedimentation.Because of floc sedimentation is thinner, reduce the consumption of non-polar oil greatly, add emulsifying technology to non-polar oil, make non-polar oil

Consumption only is a feed coal 0.5-10 kilogram per ton.Because the floc sedimentation size is less, obviously alleviate the machinery folder of fourth floc sedimentation simultaneously to the grey tail coal of height

Band has improved sharpness of separation; 3. in order further to reduce the mechanical entrapment of cleaned coal floc sedimentation, improve sharpness of separation, can adopt two-way floc sedimentation method, promptly use the grey tail coal of height

Non-polar oil floc sedimentation microfine cleaned coal particle is with electrolyte or high molecular polymer flocculation or the high grey tail coal particle of floc sedimentation microfine; 4. made full use of the high characteristics of froth flotation sharpness of separation, the cleaned coal floc sedimentation has been sorted out from the grey tail coal of height, and according to final cleaned coal

If the requirement difference of ash content is provided with in individual selected link; 5. the cleaned coal floc sedimentation dehydration that utilizes filter press that minute numerous is gone out because cleaned coal is the floc sedimentation shape, can improve its dehydrating effect, adds filter cake moulding heating power in dry, and the moisture of head coal product is further reduced,

It is as shown in the table to the separation results of several feed coals of difference for technology of the present invention, by this separation results as seen, when the raw material pit ash is low, can obtain the ultra clean coal of high yield, shown in 4,6 and No. 7 tests.And for coal slime and floating tail-coal outside the higher middle coal of ash content, the factory, all optionally go out ash content and be lower than 12% cleaned coal, and clean coal yield is all more than 50%, that is to say, for these cheap products of coal preparation plant, use this technology, from 2 tons, can select at least in coal or the tail coal to meet more than 1 ton and sell the head coal product that requires.By No. 2 tests as seen, this sorting process desulfurized effect is fairly obvious, and its sulphur content drops to 0.51% of cleaned coal by 2.99% of feed coal, and desulfurization degree reaches 83.19%.

Table physical depth deliming and desulphurizing technology is to the separating effect of different coals

Test number	Coal	Feed coal		Cleaned coal			The flammable body rate of recovery, %	Desulfurization degree %
									A ad，％	S tad，％	A ad，％	γ，％	S tad，％
		1	Coal in the coking coal	32.1		11.2								69.8		91.3
2	Coal in the high-sulfur coking coal						28.88	2.99	8.96	69.21	0.51	87.61	88.19
		3	Coal slime outside the coking coal factory	39.7		11.6								72.2		90.8
4	Coal slime outside the smokeless coal works						17.1		1.6 3.1	51.8 74.0		61.5 86.5
		5	1/3 coking coal floating tail-coal	29.72		8.29 8.83 8.87								60.24 63.48 68.05		78.61 82.83 88.40
6	Long flame coal cinder cleaned coal						3.11		1.36 1.42 1.50	73.5 82.3 89.1		74.8 83.7 90.6
		7	The anthracite floatation clean coal	7.89		0.54 0.74 1.17								44.75 53.59 65.74		48.92 57.75 70.54

The present invention can be applied to: 1. reduce the ash content of coking coal cleans significantly, for production high-quality metallurgical coke and cupola coke provide ash content to be lower than 6%, sulphur content be lower than 1% excellent

The matter head coal product.For the design that realizes this purpose is, at first select ash content in advance and be lower than 6% low ash extract coal with conventional gravity preparation,

Part as final low ash extract coal product.Get rid of high grey spoil and oarse-grained pyrite in the raw coal simultaneously, material is used again in the middle of it

This technology sub-elects ash content and is lower than 6% low ash extract coal, merges as final low ash extract coal product with low grey piece cleaned coal again; 2. the ash content that obtains high yield from common washing cleaned coal or low grey raw coal is the ultra clean coal of 1.5%-2.0%, to the also optional ash discharge of indivedual coals

Divide and be lower than 1.0% ultrapure coal.These ultralow culms are preparation top-grade active carbons, substitute the petroleum coke manufacturing electrode of import, make conduct

The quality raw materials of the substitute of the carbon black of filler and other carbon industry demand.Also can prepare the meticulous of replacement heavy diesel fuel with this ultralow culm

Water-coal-slurry; 3. handle coal in coal slime, floating tail-coal and the gravity treatment of rare coal (as the coking coal and the rich coal of China) coal preparation plant.These colm sales difficulties,

Stack or all serious environment pollutions that acts as a fuel.Utilize this technology, can therefrom select to meet and sell the cleaned coal that requires, both solved its heap

Put problem of environment pollution caused, created economic benefit again, saved rare coal resources; 4. when utilizing this technology to select low ash extract coal, its fine intermediate product directly is prepared into water-coal-slurry as boiler oil.And its ash content is up to 70%

The grey tail coal of ultra-fine height itself is exactly a kind of good raw material of developing building materials.

Claims (3)

1, the sorting process of inorganic mineral in a kind of deep removal coal, it is characterized in that: feed coal ultra-fine grinding organic flammable body and inorganic mineral in the coal are fully dissociated, non-polar oil by adding emulsification also applies high shear forces, make microfine low ash extract coal wherein form floc sedimentation, sub-elect the cleaned coal floc sedimentation with conventional froth flotation again;

2, according to the described sorting process of claim 1, it is characterized in that the feed coal ultra-fine grinding is fully dissociated to inorganic mineral and flammable body in the coal, the mean particle size D after the pulverizing [4.3] is 4 μ m-100 μ m;

3,, it is characterized in that the non-polar oil consumption is feed coal 0.5kg-10kg per ton according to the described sorting process of claim 1.