CN204644266U - The full circulation carbonization furnace that a kind of destructive distillation is lower-grade metamorphic bituminous - Google Patents

Abstract

The utility model provides a full-cycle retort furnace for retorting low-modified bituminous coal. The retort furnace body is divided into a preheating section, a retort section and a cooling section from top to bottom. The top of the retort furnace body is provided with a preheating Auxiliary coal bunker connected by two sections, the upper end of the auxiliary coal bunker is connected with the raw coal storage bin through the electro-hydraulic flapper valve; the cooling section is connected with multiple coke discharge boxes, the lower end of the coke discharge box is connected with a star discharge valve, the cooling section And the inside of the coke discharge box is interspersed with a heat exchange gas pipeline. The cooling gas enters from the heat exchange gas pipeline at the lower part of the coke discharge box and contacts with the red hot semi-coke in reverse to absorb sensible heat. After the heat exchange is completed, it is led out of the furnace through the pipeline; There is a thermal cycle gas input pipe, and the retort section is also equipped with a thermal cycle gas distribution archway that evenly disperses the semi-coke that has been retorted to each coke discharge box. The utility model adopts the direct contact of raw coal and thermal cycle gas to complete dry distillation, has high thermal efficiency and fast heat transfer, and solves the disadvantage of low calorific value of gas produced by dry distillation of low metamorphic bituminous coal in the industry.

Description

A full cycle dry distillation furnace for dry distillation of low metamorphic bituminous coal

technical field

The utility model relates to the technical field of low-rank coal processing, in particular to a full-circulation dry distillation furnace for dry distillation of low metamorphic bituminous coal.

Background technique

According to the degree of coalification, raw coal can be divided into low-rank coal, middle-rank coal and high-rank coal. Low-rank coal mainly includes lignite and low-metamorphic bituminous coal (long-flame coal, non-caking coal, and weakly caking coal). The proven reserves of low-rank coal resources in China are 4664.78×10 ⁸ t (of which the proven reserves of low-metamorphic bituminous coal are 3330.09×10 ⁸ t), accounting for 45.68% of the country’s total coal resources (of which low-metamorphic bituminous coal accounts for 45.68% of the country’s coal resources. 32.61% of the total resources), accounting for 63.06% of non-coking coal (of which low-metamorphic bituminous coal accounts for 45.01% of non-coking coal).

Most of the low-metamorphic bituminous coal in my country is directly burned as power coal, and a small part is used as raw material for carbonization and gasification, and the solid product obtained is called semi-coke. Semi-coke, also known as semi-coke, is a new type of carbon material with the characteristics of high fixed carbon, high specific resistance, high chemical activity, low ash content, low aluminum, low sulfur and low phosphorus, and can partially replace coke (metallurgical Coke) and used in chemical industry, smelting, gas making and other industries.

At present, low metamorphic bituminous coal dry distillation is mainly carried out by internal heating vertical carbonization furnace. Industrial application furnace types include SH series of Shaanxi Metallurgical Design and Research Institute Co., Ltd., SJ series developed by Shaanxi Shenmu County Sanjiang Coal Chemical Co., Ltd. and Sinosteel Co., Ltd. The ZNZL series designed by the Group's Anshan Thermal Energy Research Institute (Wang Yongjun published a paper report on pages 23-26 of "Chemical Industry" in September 2009, Volume 27, Issue 9, other furnace types and processes can be found in this article.). The heating principles of these three furnace types are basically similar. Air is blown into the furnace and the "high-temperature waste gas" generated by gas combustion provides heat for dry distillation of raw coal. The dry distillation gas is mixed with "high-temperature waste gas" and then exported to the outside of the furnace for recycling after washing and purification. Coal tar and gas. The processed gas contains a large number of useless components and has a low calorific value. The sum of nitrogen and carbon dioxide components is as high as about 50%, and the gas calorific value is low. As a result, the follow-up gas purification system is huge, and the comprehensive utilization of downstream gas is limited or investment is increased. It is of great significance to improve the existing dry distillation equipment and improve the effective components of gas for the subsequent comprehensive utilization of gas.

Utility model content

The purpose of this utility model is to overcome the problems existing in the above-mentioned prior art, and provide a full-cycle retort furnace for low-temperature carbonization of low-modified bituminous coal, aiming at solving the disadvantages of low calorific value of gas produced by carbonization of low-modified bituminous coal in the industry.

In order to achieve the above object, the utility model provides a full-cycle retort furnace for low-temperature carbonization of low-deteriorated bituminous coal, and its technical scheme is as follows: A full-cycle retort furnace for dry distillation of low-deterioration bituminous coal, including a retort furnace body, From top to bottom, the body is divided into: preheating section, retort section and cooling section. The top of the retort furnace body is provided with an auxiliary coal bunker connected with the preheating section. The upper end of the auxiliary coal bunker passes through the electro-hydraulic The valve is connected with a raw coal storage bin; the cooling section is connected with a plurality of coke discharge boxes, and the lower end of the coke discharge box is connected with a star discharge valve, and a heat exchange gas pipeline is interspersed inside the cooling section and the coke discharge box; the dry distillation section The bottom of the boiler is equipped with a thermal cycle gas input pipe, and the retort section is also equipped with a thermal cycle gas distribution archway that evenly disperses the semi-coke that has been retorted to each coke discharge box.

The upper end of the above-mentioned preheating section is provided with a distributor, and the top of the distributor is provided with a gas collecting pipe that can suck out the carbonization furnace gas.

There are 4 feeding points leading to the preheating section of the retort furnace body in the auxiliary coal bunker, and the distributor is set at the upper end of the preheating section below the feeding point.

An explosion-proof cover is provided on the above-mentioned auxiliary coal bunker.

The above-mentioned preheating section, dry distillation section and cooling section are all equipped with thermocouples connected to external temperature measuring devices.

There is an air distribution chamber inside the heat circulation gas distribution archway, and the air distribution chamber is equipped with a heat circulation gas inlet and an air intake hole of the heat circulation gas input pipe.

The air distribution chamber is provided with a thermocouple connected to an external temperature measuring device.

Beneficial effects of the utility model: the utility model is provided with a feeder in the preheating section of the retort furnace to distribute the raw coal evenly, and is provided with a thermal circulation gas distribution archway inside the retort section to complete the retort process; the retort process is completed by recycling cold gas The waste heat of semi-coke is used as the raw material of thermal cycle gas, and the waste heat is fully utilized. The utility model adopts the direct contact of raw coal and thermal cycle gas to complete dry distillation, has high thermal efficiency and fast heat transfer, and solves the disadvantage of low calorific value of gas produced by dry distillation of low metamorphic bituminous coal in the industry.

The utility model will be described in further detail below in conjunction with the accompanying drawings.

Description of drawings

Fig. 1 is the structural representation of the utility model.

Explanation of reference signs: 100, raw coal storage bin; 110, electro-hydraulic slide valve; 120, auxiliary coal bunker; 130, explosion-proof cover; 200, gas collecting pipe; 210, distributor; Thermocouple; 240, thermal cycle gas distribution archway; 250, air distribution chamber; 260, thermal cycle gas inlet; 270, air inlet; 310, coke discharge box; 320, heat exchange gas pipeline; 330, star discharge Feed valve.

Detailed ways

Example 1:

As shown in Figure 1, the utility model provides a full-cycle retort furnace for retorting low-metamorphism bituminous coal, including a retort furnace body 220. According to the temperature gradient change, the retort furnace body 220 is divided into: preheating section, retort section and cooling section, the top of the retort furnace body 220 is provided with an auxiliary coal bunker 120 communicating with the preheating section, and the upper end of the auxiliary coal bunker 120 is connected with a raw coal storage bin 100 through an electro-hydraulic flapper valve 110 , the electro-hydraulic slide valve 110 can be opened regularly for cutting, wherein the auxiliary coal bunker 120 is welded to the top of the retort furnace body 220; the auxiliary coal bunker 120 is set between the raw coal storage bin 100 and the retort furnace body 220 The purpose is to achieve sealed feeding; the cooling section is connected with a plurality of coke discharge boxes 310, the lower end of the coke discharge box 310 is connected with a star discharge valve 330, and the cooling section and the coke discharge box 310 are interspersed with heat exchange gas Pipeline (320), the cooling gas enters from the heat exchange gas pipeline at the lower part of the coke discharge box and contacts with the hot semi-coke in reverse to absorb sensible heat, and after heat exchange is completed, it is led out of the furnace through the pipeline. The outlet of the heat exchange gas pipeline 320 is set on the upper part of the cooling section, embedded in the interior of the retort furnace wall, and connected with the external pipeline after a reserved flange.

The bottom of the retort section is provided with a thermal cycle gas input pipe, and the retort section is also provided with a thermal cycle gas distribution archway 240 that uniformly disperses the carbonized semi-coke to each coke discharge box 310. The thermal cycle gas distribution archway 240 There is an air inlet on the top, and a herringbone-shaped distributor is built on the top, and the dried raw coal is distributed to each carbonization channel to exchange heat with the thermal cycle gas in reverse to complete the carbonization. The cooling section and the coke discharge box are equipped with heat exchange gas pipelines, which are in reverse contact with the semi-coke discharged from the dry distillation section to complete the cooling process, and the cooled semi-coke is discharged out of the furnace through the star discharge valve.

Example 2:

On the basis of Example 1, the upper end of the preheating section is provided with a distributor 210, and the top of the distributor 210 is provided with a gas collecting pipe 200 that can suck out the carbonization furnace gas. The auxiliary coal bunker 120 is provided with 4 blanking points leading to the preheating section of the retort furnace body. The distributor 210 is located at the upper end of the preheating section and is located below the blanking point. The raw coal entering the carbonization furnace is evenly distributed; the gas collection pipe can realize the gas collection function; the distributor 210 is a herringbone steel structure welded by steel plates, and the interior of the distributor 210 is a hollow structure, which also has the function of negative pressure gas collection The gas collecting pipe 200 and its top are welded and led out of the furnace to achieve the purpose of sucking the tar-containing gas out of the furnace; the auxiliary coal bunker 120 is provided with an explosion-proof cover 130 . The preheating section, dry distillation section and cooling section are all equipped with thermocouples 230 connected to external temperature measuring devices. The heat circulation gas distribution archway 240 is provided with an air distribution chamber 250 inside, and the air distribution chamber 250 is provided with a heat circulation gas inlet 260 of a heat circulation gas input pipe. The pipes are connected by flanges, and the wall of the air chamber is provided with hot gas inlet holes 270 . The air distribution chamber 250 is provided with a thermocouple 230 connected to an external temperature measuring device.

The working process of the present utility model is as follows:

The qualified raw coal (with a particle size of 10-30mm) is sent to the raw coal storage bin 100 through a belt conveyor, and discharged into the auxiliary coal bunker 120 through the electro-hydraulic flapper valve 110. Fall into the carbonization furnace 220;

As the raw coal enters the preheating section of the carbonization furnace (temperature below 300°C) during the falling process, the properties of the raw coal will not change at this stage, and the moisture and gas adsorbed by the raw coal are mainly removed. Below 120°C is the dehydration and drying stage of coal; 120-300°C is the desorption of CO ₂ , N ₂ and other gases adsorbed in coal. A distributor 210 is arranged on the top of the preheating section, which also has the function of collecting air. On the one hand, the raw coal falling from the coal storage bunker is evenly dispersed to the preheating section of the carbonization furnace;

The preheated raw coal falls to the dry distillation section, the temperature of this section is 300-550°C, and the decomposition and depolymerization of coal are mainly used to form semi-coke. Raw coal undergoes decomposition and depolymerization reactions to generate a large number of gas phase components with relatively small molecular weights (mainly CH ₄ , H ₂ , unsaturated hydrocarbon gases, tar vapor, these gas phase components are called pyrolysis primary gases) and Polycondensation into blue carbon. The carbonization furnace 220 is provided with a thermal cycle gas inlet 260 at the bottom of this section. When building the retort furnace 220 and the air distribution chamber 250, the interface pipes are pre-embedded, and the surroundings of the pipes are tightly built with refractory castables.

The semi-coke is separated into the lower cooling section through the lower thermal circulation gas distribution archway 240, and the temperature at this stage is 100-550°C. The cold gas input pipe 320 provided at the lower part of the carbonization furnace 220 exchanges heat with the semi-coke produced by the carbonization. The cooled semi-coke is discharged from the star discharge valve 330 at the lower part of the full-circulation carbonization furnace.

The cooling section at the lower part of the carbonization furnace adopts indirect heat exchange to recover the waste heat of semi-coke: heat-exchanging gas pipelines are installed inside the cooling section and the coke discharge box, cold gas is fed into the tube side, and semi-coke is passed between the tubes. The hot semi-coke and the cold gas in the tube side countercurrent contact.

The hot gas after heat exchange is led out of the furnace at the upper part of the cooling section, part of it is led to the heating device outside the carbonization furnace as fuel, and part of it is heated and used as circulating heat carrier gas. The circulating heat carrier gas input pipe is connected with the thermal circulating gas inlet 260 through the flange and enters the thermal circulating gas distribution arch 240 in the retort furnace, and enters the retort raw coal in the retort furnace through the air inlet 270 provided on the thermal circulating gas distribution arch 240 , the circulating heat carrier gas after heat exchange is mixed with the pyrolyzed primary gas to form coal gas, and the coal gas rises through the dry distillation layer and the preheating layer in sequence, and is exported to the gas purification system through the gas collecting pipe 200.

The utility model uses the cooled gas to recover the residual heat of carbonized charcoal; on the other hand, the gas after absorbing heat is used as the heat carrier recycled by the retort furnace, which effectively solves the problem of low metamorphic bituminous coal retort production in the industry. low disadvantages.

The parts that are not described in detail in this embodiment are commonly known and commonly used means in this industry, and will not be described here one by one. The above examples are only illustrations of the utility model, and do not constitute a limitation to the protection scope of the utility model. All designs identical or similar to the utility model all belong to the protection scope of the utility model.

Claims (7)

1. the full circulation carbonization furnace that a destructive distillation is lower-grade metamorphic bituminous, comprise gas retort body of heater (220), it is characterized in that: described gas retort body of heater (220) is divided into from top to bottom successively: preheating section, retort section and cooling section, the top of gas retort body of heater (220) is provided with the auxiliary coal bunker (120) be communicated with described preheating section, and the upper end of auxiliary coal bunker (120) is connected with raw coal warehouse (100) by the electricity push-pull valve (110) that surges; Described cooling section is connected with multiple coke discharge box (310), and the lower end of described coke discharge box (310) is connected with star-shaped discharge valve (330), and cooling section and coke discharge box (310) inside are interspersed with heat exchange gas line (320); The bottom of retort section is provided with thermal cycling gas inlet pipe, and retort section is also provided with dispersed thermal cycling coal gas gas distribution archway (240) to each coke discharge box (310) of blue charcoal destructive distillation completed.

2. the full circulation carbonization furnace that a kind of destructive distillation as claimed in claim 1 is lower-grade metamorphic bituminous, is characterized in that, the upper end of described preheating section is provided with distributor (210), and this distributor (210) top is provided with can by the effuser of gas retort coal gas sucking-off (200).

3. the full circulation carbonization furnace that a kind of destructive distillation as claimed in claim 2 is lower-grade metamorphic bituminous, it is characterized in that, be provided with the discharging point leading to gas retort body of heater preheating section in 4 places in described auxiliary coal bunker (120), described distributor (210) is located at the lower position that preheating section upper end is positioned at discharging point.

4. the full circulation carbonization furnace that a kind of destructive distillation as claimed in claim 1 is lower-grade metamorphic bituminous, is characterized in that, described auxiliary coal bunker (120) is provided with Explosion-proof cap (130).

5. the full circulation carbonization furnace that a kind of destructive distillation as claimed in claim 1 is lower-grade metamorphic bituminous, is characterized in that, described preheating section, retort section and cooling section are equipped with the thermopair (230) connecting outside temperature measuring equipment.

6. the full circulation carbonization furnace that a kind of destructive distillation as claimed in claim 1 is lower-grade metamorphic bituminous, it is characterized in that, described thermal cycling coal gas gas distribution archway (240) inside is provided with distribution plenum (250), and distribution plenum (250) is provided with thermal cycling gas inlet (260) and air inlet port (270).

7. the full circulation carbonization furnace that a kind of destructive distillation as claimed in claim 6 is lower-grade metamorphic bituminous, is characterized in that, described distribution plenum (250) is provided with the thermopair (230) connecting outside temperature measuring equipment.