CN101757982A

CN101757982A - Coal slime floating process

Info

Publication number: CN101757982A
Application number: CN 201010125831
Authority: CN
Inventors: 刘炯天; 桂夏辉; 张海军; 陶秀祥; 王永田
Original assignee: China University of Mining and Technology CUMT
Current assignee: China University of Mining and Technology CUMT
Priority date: 2010-03-09
Filing date: 2010-03-09
Publication date: 2010-06-30

Abstract

The invention discloses a coal slime floating process, which comprises the following operations: adjusting slurry of floatation coal slime; floating the coal slime; concentrating and classifying; and regrinding and refloating middlings. Coal slime floating equipment is adopted and is matched with corresponding slurry adjusting, concentrating and classifying, and coal grinding equipment; the coal slime after slurry adjusting is floated by the floatating equipment; and the floated tailings are sorted by the concentrating and classifying equipment to prepare a middling product and a final tailing product. For the middling product with better monomial dissociation, the middling product is directly returned to the slurry adjusting operation, is subjected to slurry adjusting by the slurry adjusting equipment and then is sorted again so as to form a middling refloating process for high ash and difficult floatable coal slime; and for the middling product with poor monomial dissociation, the middling product is subjected to coal grinding operation by a coal mill, returned to the slurry adjusting operation by the slurry adjusting equipment, and then is sorted again so as to form a middling regrinding and refloating process for the high ash and difficult floatable coal slime; therefore, the conflict between the quality of clean coal and combustible component recovery rate in the floatation of the high ash and difficult floatable coal slime is solved. The coal slime floating process has the advantages of simple process, low investment, low operating cost and high separation efficiency.

Description

A kind of coal slime flotation technology

Technical field

The present invention relates to the coal slime flotation technical field, especially a kind of coal slime flotation technology that is applicable to coal regrinding and reconcentration in the high grey difficult separation coal mud.

Background technology

Coal is the main energy sources of China, accounts for about 70% of primary energy, and in the period of quite growing future, the principal status of public economy of coal in China's energy resource structure can not change.But coal is again the unholiness energy, uses coal in a large number and has caused serious atmosphere pollution.The main cause that causes this situation is that the purification techniques and the method for coal itself is also very imperfect, and the high grey difficult separation coal mud that particularly accounts for coal production about 20% can't obtain effective sorting.Along with raising, resource deterioration of geological conditions, coal preparation plant's maximization of Mechanized Coal Mining Operation in China degree are built and the dense medium separation broad application, high grey difficult separation coal mud ratio sharply increases, and be the continuation degradating trend, make the contradiction of slime separation more outstanding, cause the floatation clean coal ash content constantly to raise, the rate of recovery progressively reduces, and has seriously restricted the quality of final head coal product.Meanwhile, along with the continuous minimizing of coal reserves, as non-renewable resources, the appearance of high grey difficult separation coal mud makes slime separation be faced with new challenges, and it is also more and more obvious to expose the low problem of the rate of recovery and production efficiency in the slime separation process.

The characteristics of high grey difficult separation coal mud show mainly that the middle coal content in the coal slime is big, ash content is high, fine size, floatability difference several respects.Conventional coal slime flotation technology is to send into flotation column or flotation device with going into float coal mud after the ore pulp preprocessor is handled, and flotation column or flotation device sub-elect head coal product and tail coal product, and enter subsequent product processing operation separately.This technology is mainly used in the conventional easily sorting of coal separation mud, and uses for many years in China, has accumulated rich experience, is the most widely used floatation process of the present coal slime flotation of China.And for the sorting of the grey difficult separation coal mud of height, middle coal content height is a principal element that causes its difficult choosing, and this technology ubiquity product recovery rate and the low defective of production efficiency have seriously restricted final head coal product quality.Therefore, the key technology of developing the efficient sorting of high grey difficult separation coal mud has become a difficult problem needing solution in the coal resources efficient clean utilization process badly.

Summary of the invention

Technical problem: the object of the invention has provided that a kind of technology is simple, the high and low cost of the efficiency of separation, effective high grey difficult separation coal mud regrinding and reconcentration technology.

Technical scheme: coal slime flotation technology of the present invention comprises and feeds size mixing equipment with going into float coal mud and floating agent, after size mixing equipment is sized mixing, entering floatation equipment floatingly selects head coal product and enters the interior one-level tail coal product of the first tail coal Buffer Pool, the tail coal that floatingly selects is carried out regrinding and reconcentration, and its step is as follows:

A, will enter one-level tail coal product pump in the first tail coal Buffer Pool with first slush pump and deliver to the concentrated classifying equipoment that constitutes by hydrocyclone and classifying screen and concentrate classification;

B, will concentrate in first after the classification product of coal and send in the coal pulverizer and grind, and then in sending in the coal Buffer Pool;

C, with second slush pump with in the middle coal Buffer Pool after coal pulverizer is handled second in the product of coal pumping return in the size mixing equipment, size mixing once more, float again, select again, grind with newly going into to float material;

D, go round and begin again, repeating step a, b, c are until finishing whole flotation work.

The particle particle diameter is greater than 0.074mm in the middle product of coal after the described concentrated classification, its content less than 40%, ash content is higher than at 35% o'clock, need not to grind, in directly entering in the coal Buffer Pool.

Beneficial effect: the present invention carries out regrinding and reconcentration to the tail coal that prior art floatingly selects, especially the middle coal in the grey difficult separation coal mud of height is carried out regrinding and reconcentration, solve because of in the big coal slime difficulty that causes of coal content select problem, realization improves final head coal product quality to the efficient sorting of the grey difficult separation coal mud of height.Compare with traditional sorting process, its technological process is simple, small investment, and operating cost is low, efficiency of separation height.

Description of drawings

Fig. 1 is a sorting process FB(flow block) of the present invention.

Fig. 2 is a screening installation structural representation of the present invention.

The specific embodiment

Below in conjunction with accompanying drawing enforcement of the present invention is further described:

Coal slime flotation technology of the present invention: its step is as follows:

1, will go into float coal mud 1 and floating agent 2 and feed size mixing equipment A and size mixing, size mixing equipment A is made of agitator, the shaft that links to each other with motor, the blade that is located on the shaft;

2, enter floatation equipment B through the gravity flow of size mixing equipment A stirred materials, floatingly select head coal product 3 through floatation equipment B and discharge from the overflow launder on floatation equipment B top, the one-level tail coal product 4 through sinking after the floatation equipment B flotation enters in the first tail coal Buffer Pool F from the underflow opening through floatation equipment B;

3, will enter one-level tail coal product 4 in the first tail coal Buffer Pool F with the first slush pump G is pumped to the concentrated classifying equipoment that is made of hydrocyclone C and classifying screen D and concentrates classification;

4, the one-level tail coal product 4 that concentrates classification is introduced into hydrocyclone C and carries out sorting, the material of come-up is as secondary tail coal product 6, top through hydrocyclone C overflows, the material 5 of sedimentation enters classifying screen D through underflow opening, the material of saturating sieve is as three grades of tail coal products 7, the saturating product that sieves is the middle product of coal 8 after the concentrated classification, and secondary tail coal product 6 and three grades of tail coal products 7 are merged as final tail coal product 9 by pipeline;

5, will concentrate obtain after the classification first in product of coal 8 send into earlier among the coal pulverizer E and grind, in sending into then in the coal Buffer Pool H; The particle particle diameter is greater than 0.074mm in the middle product of coal 8 after concentrating classification, its content less than 40%, ash content is higher than at 35% o'clock, need not to grind, in directly entering in the coal Buffer Pool H;

6, with the second slush pump I with in the middle coal Buffer Pool H after coal pulverizer has ground second in product of coal 10 pumpings return in the size mixing equipment A, size mixing once more, float again, select again, grind with newly going into to float material;

7, go round and begin again, repeating step a, b, c are until finishing whole flotation work.

Claims

1. coal slime flotation technology, comprise and to go into float coal mud (1) and floating agent (2) feeds size mixing equipment (A), after size mixing equipment (A) is sized mixing, entering floatation equipment (B) floatingly selects head coal product (3) and enters the interior one-level tail coal product (4) of the first tail coal Buffer Pool (F), it is characterized in that: the one-level tail coal product (4) that floatingly selects is carried out regrinding and reconcentration, and its step is as follows:

A, will enter the concentrated classifying equipoment that the one-level tail coal product (4) in the first tail coal Buffer Pool (F) is pumped to by hydrocyclone (C) and classifying screen (D) formation with first slush pump (G) and concentrate classification;

B, will concentrate in first after the classification product of coal (8) and send in the coal pulverizer (E) and grind, and then in sending in the coal Buffer Pool (H);

C, with second slush pump (I) with in the middle coal Buffer Pool (H) after coal pulverizer is handled second in product of coal (10) pumping return in the size mixing equipment (A), size mixing once more, float again, select again, grind with newly going into to float material;

2. coal slime flotation technology according to claim 1, it is characterized in that: the middle particle particle diameter of product of coal (8) is greater than 0.074mm in first after the described concentrated classification, its content less than 40%, ash content is higher than at 35% o'clock, need not to grind, in directly entering in the coal Buffer Pool (H).