CN205323967U - System is selected separately to low order thermal coal - Google Patents

Abstract

The utility model discloses a system is selected separately to low order thermal coal, include that the tension and relaxation is sieved, shallow slot sorting machine, clean coal sculping screen and waste rock sculping screen heavily are situated between, the sieve diameter of tension and relaxation sieve is 6mm for the raw coal of treating into washing sieves, the shallow slot sorting machine that heavily is situated between is used for coming from the oversize of tension and relaxation sieve is selected separately to the sorting obtains waste rock and clean coal product, it is right that the clean coal sculping screen is used for the clean coal product that shallow slot sorting machine's the branch of heavily being situated between was elected takes off jie, it is right that the waste rock sculping screen is used for the waste rock that shallow slot sorting machine's the branch of heavily being situated between was elected takes off jie. The utility model discloses a shallow slot coal preparation technique that aggravates to be situated between is sieved to a sieve 6mm dry process degree of depth of speeding, all directly advances the shallow slot washing that heavily is situated between with the 6mm oversize first, has effectively improved the income rate of washing of low order thermal coal, by a wide margin the volume of reducing the coal slime.

Description

A kind of low order steam coal separation system

Technical field

This utility model relates to coal washing field, particularly to a kind of low order steam coal separation system。

Background technology

At present, China's thermal coal coal preparation technique is based on dense medium separation。Owing to heavy media coal separation has efficiency of separation height, sharpness of separation is high, and separating density range of accommodation is big, and to coal strong adaptability, sorting particle size range is wide, and production process easily realizes features such as automatically controlling, is particularly well-suited to difficult separation coal and extremely difficult coal separation sorting。At present, heavy media coal separation method ratio shared by various countries' coal preparation method is increasing, and France, the U.S., Australia and South Africa have accounted for 60%, 66%, 90% and more than 90% respectively。Lump coal separation equipment mainly has pneumatic separator, lump coal jigging machine, movable-sieve jig, shallow slot heavy-media separator, inclined lifting wheel separator, vertical lifting wheel separator。Owing to shallow-tank separator simple in construction, disposal ability are big, easy to operate, failure rate is low, so being widely adopted in recent years, become the main coal preparation method that domestic thermal coal coal separation adopts。The main screening installation of smalls has mixed coal jigging machine and heavy medium cyclone。Wherein heavy medium cyclone utilizes centrifugal force strengthening coal and the spoil sorting at gravitational field, the efficiency of separation can be improved, because of its simple in construction, movement-less part, treating capacity is big, the efficiency of separation is high, worldwide it is widely adopted, but there is also for steam coal separation dense medium cyclone and produce the problem that secondary slime is many。

Super-huge power coal preparation plant of China commonly used 13mm (or 25mm) grade washing technique, mainly to lump coal by dense-medium shallow-tank dressing of coal by washing, smalls generally does not enter to wash。Indivedual coal preparation plants once attempt taking wholegrain level washing method, but create the coal slime being difficult to process and utilize in a large number。Finding in actual production, wholegrain level enters the washing efficiency washed and declines, and after indivedual coal preparation plants even washing occur, product caloric value is lower than the phenomenon of raw coal。Particularly low order thermal coal, owing to degree of coalification is shallow, ature of coal is soft, frangible, meets the easy argillization of water, and washing lower limit is more low, and the slime content of generation is more big, thus coal slime is difficult to process and utilize, and causes that it enters to wash rate low, and washing efficiency is low。

Summary of the invention

The purpose of this utility model is in that to provide a kind of low order steam coal separation system, to solve the low order thermal coal problem that ubiquitous washing efficiency is low when washing。

For achieving the above object, this utility model is by the following technical solutions:

A kind of low order steam coal separation system, including:

Flip flop screen, the sieve diameter of described flip flop screen is 6mm, sieves for the raw coal treated into washing；

Dense-medium shallow-tank separator, for the oversize from described flip flop screen is sorted, obtains spoil and head coal product with sorting；

Head coal sculpingscreen, for carrying out de-mediated to the head coal product sub-elected of described dense-medium shallow-tank separator；With

Coal Stone Separation, for carrying out de-mediated to the spoil sub-elected of described dense-medium shallow-tank separator。

According to separation system of the present utility model, it is preferable that the sieve diameter of described head coal sculpingscreen and Coal Stone Separation is 6mm。

According to separation system of the present utility model, it is preferable that described head coal sculpingscreen and Coal Stone Separation are banana screen。

According to separation system of the present utility model, it is preferable that described flip flop screen is provided with multiple stage, and described multiple stage flip flop screen is arranged in parallel；Described dense-medium shallow-tank separator is provided with two, and two described dense-medium shallow-tank separators are arranged in parallel。

According to separation system of the present utility model, it is preferable that described flip flop screen is the LF3.0-8.82/28ED type flip-flow screening machine of Mantidis Li Weier company of Holland。

According to separation system of the present utility model, it is preferable that described dense-medium shallow-tank separator is the W26F54 type dense-medium shallow-tank separator of Bi Desi company of the U.S.。

Compared with prior art, this utility model has the advantage that

1, this utility model adopts flip-flow screening machine 6mm dry deep-sizing to add dense-medium shallow-tank coal preparation technique, first 6mm oversize is all directly entered dense-medium shallow-tank washing, improve coal separation efficiency and the scope of application of dense-medium shallow-tank coal preparation technique further, breach traditional dense-medium shallow-tank 13 (or 25) mm washing lower limit, achieving dense-medium shallow-tank 6mm degree of depth washing, enter the rate of washing and improve 20%-30%, washing efficiency reaches 98%, be effectively increased low order thermal coal enter to wash rate, slime content is greatly decreased。

2, compared with wholegrain level Washing Steam Coal technique, not only eliminate smalls washing system, and slime content reduces 10-15 percentage point, solves the process of a large amount of coal slime and utilizes a difficult problem, achieve coal slime minimizing to produce, make coal preparation plant's investment and production cost significantly decline。

Accompanying drawing explanation

Fig. 1 is the process chart of a kind of embodiment of the present utility model。

Detailed description of the invention

Below in conjunction with accompanying drawing, this utility model is described in detail, but this utility model is not limited to that。

As it is shown in figure 1, separation system of the present utility model includes flip flop screen 1, dense-medium shallow-tank separator 2, head coal sculpingscreen 3 and Coal Stone Separation 4；Wherein, the sieve diameter of described flip flop screen 1 is 6mm, sieves for the raw coal treated into washing, and gained oversize is sent directly into dense-medium shallow-tank separator 2 and sorts。Described flip flop screen 1 is the common equipment in coal washing field, is made up of inside and outside two screen boxs, connects by supporting spring, and flexible sieve plate is separately fixed on the crossbeam of inside and outside screen box, has broken the traditional structure pattern that sieving machine rigid screen does not do relative motion。When inside and outside screen box moves back and forth in opposite directions, periodic movement lax during tensioning when sieve plate does, its scatter radius is 30～50 times of acceleration of gravity, is prevented effectively from materials from bonding, and the compass screen surface of tension and relaxation deformation can liberate the granule of blocking。In one embodiment, described flip flop screen 1 is provided with multiple stage, for instance 4, and described multiple stage flip flop screen 1 is arranged in parallel, and improves the disposal ability of separation system of the present utility model。Preferably, described flip flop screen 1 is the LF3.0-8.82/28ED type flip-flow screening machine of Mantidis Li Weier company of Holland。

Described dense-medium shallow-tank separator 2, for the oversize from described flip flop screen 1 is sorted, obtains spoil and head coal product with sorting。Described dense-medium shallow-tank separator 2 is preferably provided with two, and two described dense-medium shallow-tank separators 2 are arranged in parallel, for instance for arranging 4 flip flop screens 1, every dense-medium shallow-tank separator 2 all accepts the oversize of described 4 flip flop screen 1, in order to flexible load。

Described dense-medium shallow-tank separator 2 is the common equipment in coal washing field, coal is sorted in gravitational field according to Archimedes principle, and the heavy-media suspension in shallow slot is divided two parts to send into by qualification medium pump, forms horizontal flow and upwelling。Swim in top lower than the light product of Media density, and cross downflow weir at the flows by action of horizontal flow, become head coal product；It is spoil higher than the material of working media density, sinks to bottom cell body, the scraper plate of the low speed of service scrape shallow-tank separator。Preferably, described dense-medium shallow-tank separator 2 is the W26F54 type dense-medium shallow-tank separator of Bi Desi company of the U.S. (Peters)。

It is verified following with the W26F54 type dense-medium shallow-tank separator of Bi Desi company of the U.S.:

Needed for taking every meter of groove width, heavy-media suspension total amount is 175-200m3/h, what upwelling was generally horizontal flow 1/3 is advisable, i.e. the flow of upwelling is 40-50m3/ (h m), calculating by common 1.6m separation length, upflow velocity is 0.70-0.85cm/s。

Gently, the separating rate of heavy material not only relevant with density of suspending liquid, viscosity, flow field characteristic, material density, and closely related with sorted materials granularity。According to fluid mechanics principle, when ore grain movement reynolds number Re is when 2-300, its termin al velocity can adopt A Lian formula to calculate, it may be assumed that

$V_0=d{\left(\frac{2}{15}g\frac{\mathrm{\δ}-\mathrm{\ρ}}{\mathrm{\ρ}}\right)}^{\frac{2}{3}}{\left(\frac{\mathrm{\ρ}}{\mathrm{\μ}}\right)}^{\frac{1}{3}}---\left(1\right)$

In formula, V₀The termin al velocity of-ore particle, cm/s；D-ore particle particle diameter, cm；G-acceleration of gravity, cm/s2；δ-ore particle density, g/cm3；ρ-density of suspending liquid, g/cm3；μ-suspension kinematic viscosity, P (pool)。

In actual screening installation, termin al velocity is converted into hindered falling end speed and just can show that ore particle is to enter weight product or enter the conclusion of light product within certain sorting time:

VCT=V₀ψβ(2)

In formula, VCT-ore particle hindered falling end speed, cm/s；ψ-ore particle form factor, ψ=0.8；β-annoyance level coefficient, β=0.4-0.5, take 0.45。

The viscosity of heavy-media suspension depends primarily on density of suspending liquid, raises viscosity with density and increases, as ρ=1.4-1.9g/cm3, and μ=0.13-0.25P (pool)。Take sorting the most disadvantageous suspension viscosity value μ=0.25P, according to above-mentioned formula (1), formula (2), when ore particle particle diameter is 6mm (i.e. 0.6cm), ore particle hindered falling end speed result of calculation such as table 1 under different densities。

Hindered falling end speed under table 16mm ore particle different densities

Note *: the negative value of hindered falling end speed represents the ascent rate of light product。

From table 1, when density of suspending liquid is at 1.65-1.70g/cm³Time, even if at higher viscosities, poor with density of suspending liquid it is only 0.05g/cm³Ore particle, its terminal velocity is all higher than 1cm/s, higher than the upflow velocity (0.70-0.85cm/s) of dense-medium shallow-tank。Therefore, utilizing dense-medium shallow-tank to carry out 6mm degree of depth washing is feasible technically。

Described head coal sculpingscreen 3 is for carrying out de-mediated to the head coal product sub-elected of described dense-medium shallow-tank separator 2；Described Coal Stone Separation 4 is for carrying out de-mediated to the spoil sub-elected of described dense-medium shallow-tank separator 2。Described head coal sculpingscreen 3 and Coal Stone Separation 4 are the common equipment in coal washing field, know for described in this area, it is possible to select head coal sculpingscreen commonly used in the art and Coal Stone Separation。Preferably, the sieve diameter of described head coal sculpingscreen 3 and Coal Stone Separation 4 is 6mm；It is further preferred that described head coal sculpingscreen 3 and Coal Stone Separation 4 are banana screen。

By the following examples this utility model is further described。

Lee family's moat Raw Coal (low order thermal coal) treating capacity is 2272.72t/h, adopts flip flop screen 6mm deep screening+dense-medium shallow-tank degree of depth washing process pattern。Raw coal average ash is 24.86%, total moisture 21.61%, caloric value 3938kcal/kg, sulphur content 0.88% ,+13mm grade productivity 52.35%, 13-6mm grade productivity 15.03%。Selecting 4 Dutch Mantidis Li Weier LF3.0-8.82/28ED flip-flow screening machines to carry out 6mm deep screening, separate unit disposal ability average out to 659t/h, dense-medium shallow-tank separator 2, for the W26F54 type dense-medium shallow-tank separator of Bi Desi company of the U.S.。Enter the related data washed to contrast in Table 2 with traditional lump coal washing or wholegrain level。

Table 2

From table 2, adopting washing new technology of the present utility model compared with traditional+13mm (or+25mm) dense-medium shallow-tank washing (smalls does not enter to wash), raw coal enters to wash rate and improves 20%-30%, and marketable coal caloric value improves more than 500kcal/kg；Compared with wholegrain level Washing Steam Coal technique, not only eliminate smalls washing system, and slime content reduces 10-15 percentage point, not only solve the process of a large amount of coal slime and utilize a difficult problem, and significantly reduce marketable coal moisture, achieve coal slime minimizing to produce, and simplify slurry circulating system, make coal preparation plant's investment and production cost significantly decline。Therefore, the features such as the coal preparation technique of this project development has reduced investment, washing efficiency is high, processing cost is low and quality of commercial coal is good。

Claims (6)

1. a low order steam coal separation system, including:

Flip flop screen, the sieve diameter of described flip flop screen is 6mm, sieves for the raw coal treated into washing；

Dense-medium shallow-tank separator, for the oversize from described flip flop screen is sorted, obtains spoil and head coal product with sorting；

Head coal sculpingscreen, for carrying out de-mediated to the head coal product sub-elected of described dense-medium shallow-tank separator；And Coal Stone Separation, for the spoil sub-elected of described dense-medium shallow-tank separator is carried out de-mediated。

2. separation system according to claim 1, it is characterised in that the sieve diameter of described head coal sculpingscreen and Coal Stone Separation is 6mm。

3. separation system according to claim 2, it is characterised in that described head coal sculpingscreen and Coal Stone Separation are banana screen。

4. the separation system according to any one of claim 1-3, it is characterised in that described flip flop screen is provided with multiple stage, and described multiple stage flip flop screen is arranged in parallel；Described dense-medium shallow-tank separator is provided with two, and two described dense-medium shallow-tank separators are arranged in parallel。

5. separation system according to claim 4, it is characterised in that described flip flop screen is the LF3.0-8.82/28ED type flip-flow screening machine of Mantidis Li Weier company of Holland。

6. separation system according to claim 5, it is characterised in that described dense-medium shallow-tank separator is the W26F54 type weight shallow slot medium separator of Bi Desi company of the U.S.。