CN110760314B

CN110760314B - Coke refining method and coke refining furnace

Info

Publication number: CN110760314B
Application number: CN201911002035.8A
Authority: CN
Inventors: 陈良明
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-10-21
Filing date: 2019-10-21
Publication date: 2020-11-06
Anticipated expiration: 2039-10-21
Also published as: CN110760314A

Abstract

The invention provides a coke refining method with high coking efficiency and a coke refining furnace, which comprises the steps of introducing a mixed gas of carbon monoxide and steam into a coking layer to perform a shift reaction to release heat and promote rapid coking; the coke refining furnace comprises a furnace body, wherein a grate is arranged at the bottom in the furnace body, the grate is conical and hollow inside, an air channel is formed in the side wall of the grate, an air inlet communicated with an external air source is formed in the bottom, and mixed gas of steam and carbon monoxide enters a cavity in the grate from the air inlet and then is discharged from the air channel; coal piles up in the furnace body from top to bottom and forms dry distillation layer, drying layer, the layer of coking, cooling layer in proper order, and the steam and the partly mixed gas of carbon monoxide that are discharged by the air duct get into the cooling layer after upwards looping through the layer of coking, drying layer, dry distillation layer back and discharging through furnace body top blast pipe.

Description

Coke refining method and coke refining furnace

Technical Field

The invention relates to the technical field of coking, in particular to a coke refining method and a coke refining furnace.

Background

In terms of environmental protection, the first generation of coke ovens (i.e., "earth kilns") were operated by air from the bottom of the coke oven in a natural state to burn with the char to generate heat (in cooperation with the heat generated by the combustion of combustible gases generated by the coke ovens) to raise the temperature of the coal. The coke oven outlet gas thus produced contains a large amount of nitrogen, which is not only beneficial to the recovery of useful gases of carbon monoxide and the recovery of residual heat and sensible heat, but also is not beneficial to the removal or recovery of carbon dioxide, the removal and recovery of sulfur and the removal or recovery of benzene, phenol and tar.

The second generation coke oven is characterized in that a closed space at the periphery of the coke oven is used as a combustion chamber, and air and coal gas are combusted in the combustion chamber to generate heat to heat coal in the coke oven. Therefore, the gas generated in the combustion chamber is greatly reduced compared with the first generation coke oven, and the cleaning and the recovery of the gas and the cleaning and the recovery of the sulfur are facilitated, while the gas generated in the coke oven is less, and the cleaning and the recovery of the carbon monoxide, the cleaning and the recovery of benzene, phenol, tar and the like and the cleaning and the recovery of the sulfur are facilitated. Thus, the second generation coke oven technology is capable of cleaning and recovering essentially all harmful gases other than carbon dioxide. However, the phenomenon that carbon dioxide is discharged to the atmosphere after the gas is combusted is a common phenomenon, the carbon dioxide is not required to be absorbed and then discharged, and the recovery cost is naturally huge because the main component in the gas is nitrogen.

Disclosure of Invention

The invention aims to overcome the defects of the prior art, adapt to the practical requirements and provide a coke refining method with high coking efficiency and a coke refining furnace.

In order to realize the purpose of the invention, the technical scheme adopted by the invention is as follows:

the invention discloses a coke refining method, which comprises the steps of introducing a mixed gas of carbon monoxide and steam into a coking layer to carry out shift reaction and release heat and promote quick coking.

Coal in the coke oven is stacked from bottom to top in sequence, and high-temperature gas generated after the shift reaction of carbon monoxide and water vapor in the coking layer at the bottom layer is discharged out of the oven body after passing through the dry distillation layer and the drying layer in sequence.

Before entering the coking layer, the mixed gas of carbon monoxide and steam contacts with coke in the cooling layer to cool the coke, and then the temperature of the mixed gas is raised before entering the coking layer.

The invention further discloses a coke refining furnace, which comprises a furnace body, wherein the bottom in the furnace body is provided with a grate, the grate is conical and hollow inside, the side wall of the grate is provided with an air channel, the bottom is provided with an air inlet communicated with an external air source, and mixed gas of steam and carbon monoxide enters the cavity in the grate from the air inlet and then is discharged from the air channel;

grate maximum diameter edge sets up with furnace body inner wall interval, and the furnace body bottom has seted up the feed opening, and coal from top to bottom piles up in the furnace body and form dry distillation layer, dry layer, smelts burnt layer, cooling layer in proper order, gets into the cooling layer by air duct exhaust steam and carbon monoxide gas mixture and upwards loops through after coking layer, dry distillation layer and the blast pipe discharge at furnace body top.

And a cooling box communicated with the feed opening is arranged outside the furnace body, cooling water is filled in the cooling box, and coke in the cooling layer enters the cooling box for cooling.

The bottom of the cooling box is provided with a coke outlet.

The inner wall of the furnace body is provided with a heat-preservation refractory brick lining layer.

The top of the furnace body is provided with a feed inlet.

The furnace grate comprises a furnace wall at the bottom and a conical body positioned at the top of the furnace wall, an inner cavity of the furnace wall is communicated with an inner cavity of the conical body, and the diameter of the furnace wall is smaller than that of the conical bottom of the conical body.

The furnace wall can rotate and drive the cone-shaped bodies to rotate synchronously.

The invention has the beneficial effects that:

the invention utilizes the carbon monoxide and the vapor to carry out the shift reaction in the environment of high-temperature carbon, and the released heat further heats the carbon to reach the temperature required by coking, thereby realizing the coking purpose, and the coking enterprises can use the technology of the invention to ensure that the enterprises can achieve the environmental protection goal of not discharging any industrial harmful gas into the air as far as possible in the production, particularly the carbon dioxide of the greenhouse gas can realize zero emission, and the waste is changed into the valuable to obtain the carbon dioxide product; the heat utilization rate in production can be greatly improved, and the economic benefit is increased; the invention is an upgrade to the useful gas generated by coking, the former coke oven only passively generates a small amount of carbon monoxide and a small amount of hydrogen, but the invention actively generates a large amount of hydrogen and a small amount of carbon monoxide, and is a conscious creation of chemical raw material gas, so that the industrial transformation upgrade can be carried out according to the invention.

Drawings

FIG. 1 is a schematic view showing the internal structure of a coke oven according to the present invention;

fig. 2 is a schematic view of the driving structure for rotating the grate in the present invention.

Detailed Description

The invention is further illustrated with reference to the following figures and examples:

example 1: a coke refining furnace is shown in figures 1 and 2.

The steam and carbon monoxide mixed gas furnace comprises a furnace body 2, wherein a grate is arranged at the bottom in the furnace body 2, the grate 4 is conical and hollow inside, an air channel 5 is formed in the side wall of the grate 4, an air inlet 7 communicated with an external air source is formed in the bottom, and the steam and carbon monoxide mixed gas enters a cavity in the grate from the air inlet and then is discharged from the air channel.

In the design, coal is stacked in the furnace body from top to bottom and sequentially forms a dry distillation layer 11, a drying layer 12, a coking layer 13 and a cooling layer 14, and mixed gas of steam and carbon monoxide discharged from the air duct 5 enters the cooling layer and then sequentially passes through the coking layer, the drying layer and the dry distillation layer upwards and then is discharged through an exhaust pipe at the top of the furnace body.

In the design, the edge of the maximum diameter of the grate 4 is arranged at an interval with the inner wall of the furnace body 2, so that coke formed by the coking layer can downwards move to the inside of the cooling layer from the gap between the edge and the inner wall of the furnace body, meanwhile, the bottom of the furnace body 2 is provided with a feed opening, the outside of the furnace body 2 is provided with a cooling tank 8 communicated with the feed opening, cooling water 15 is filled in the cooling tank 8, coke 16 in the cooling layer enters the cooling tank for cooling, and meanwhile, the bottom of the cooling tank is provided with a coke outlet 9.

In the design, the inner wall of the furnace body is provided with a heat-preservation refractory brick inner liner layer 3, and the top of the furnace body is provided with a feeding hole 1.

In the design, the grate comprises a furnace wall 6 at the bottom and a cone positioned at the top of the furnace wall, an inner cavity of the furnace wall 6 is communicated with an inner cavity of the cone, the diameter of the furnace wall is smaller than that of the cone bottom of the cone, and the cooling layer is positioned in a gap between the furnace wall and the inner wall of the furnace body.

In the design, the oven wall can rotate and drive the conical body to synchronously rotate, so that the grate can rotate, and when in coking, the rotation of the grate can firstly promote coke formed by the coking layer to downwards move, and secondly can prevent the coke from blocking the air duct and promoting the air duct to exhaust.

In order to realize the rotation of the grate 4, in the design, the bottom of the furnace wall is arranged at the bottom 18 of the furnace body through a bearing 19, the bottom of the furnace wall penetrates through the bearing and then is positioned outside the furnace body, meanwhile, a driving gear 17 is arranged at the end part of the furnace wall outside the furnace body, the driving gear is connected with a driving motor through a speed reducer, and thus, the driving gear is driven by the driving motor to further drive the furnace wall to rotate.

Example 2 a coke refining method, which is carried out in the coke refining furnace described in example 1, wherein coal in the coke furnace is stacked in order from bottom to top as described above, and the coal is sequentially stacked from bottom to top as a cooling layer, a coking layer, a drying layer, and a carbonization layer, wherein a mixed gas of carbon monoxide and steam is introduced into the coking layer to cause a shift reaction and release heat, thereby facilitating rapid coking, and a high-temperature gas generated by the shift reaction of carbon monoxide and steam in the coking layer at the bottom is discharged to the outside of the furnace body after passing through the carbonization layer and the drying layer in order upward.

In the process, the mixed gas of carbon monoxide and water vapor is contacted with the coke in the cooling layer before entering the coking layer to cool the coke, and then the temperature of the coke is increased before entering the coking layer.

After the mixed gas of carbon monoxide and steam enters the coking layer, the carbon monoxide and steam are subjected to shift reaction in the high-temperature carbon environment, and the carbon is further heated by the released heat to reach the temperature required by coking, so that the coking purpose is realized.

Specifically, the invention comprises the following steps:

(1) the carbon monoxide gas (or industrial water gas and semi-water gas with high concentration of carbon monoxide) from a gas source and added steam enter a coke oven through a control valve connected on an air inlet at the bottom of the coke oven body to reach the inside of a grate and reach a cooling layer in the coke oven through a grate air passage, wherein the carbon monoxide gas cools the coke which is refined, the temperature of the carbon monoxide gas rises, and part of the steam reacts with the coke in a concentration of water gas generation reaction to generate a small amount of carbon monoxide, a certain amount of carbon dioxide, a relatively large amount of hydrogen and a very small amount of methane.

In the process, the water gas generation reaction absorbs heat, the coke has a cooling effect, part of water vapor does not react due to the characteristic of concentration reaction, but the temperature rises in the process of the concentration reaction, and the heat comes from the coke, namely the coke has a cooling effect.

A small amount of carbon monoxide is combined with steam to carry out shift reaction in the process that the gases pass through the cooling layer; all gases (including added carbon monoxide, unreacted steam, water gas generated by the reaction, water gas generated by the steam generated in the cooling tank entering the cooling layer and the coke and water gas generated by the water gas generation reaction, gas after the shift reaction and unreacted steam) continuously flow upwards to the coking layer.

Because the coke surface in the cooling layer is wrapped by the ash, the water gas reaction is in a diffusion dynamics control area, so the reaction can only occur in a small amount, and the catalyst effect of the ash wrapping for cutting off the conversion reaction is reduced, so the conversion reaction also occurs in a small amount.

(2) The surface of coke in the coking layer reaches a molten state, and thus shift reaction and water gas reaction occur in large quantities. The shift reaction causes the semicoke to be heated and heated until the surface of the semicoke is heated to form a molten state (the coking process from the semicoke to the coke is in the process), and a large amount of water gas is generated at the bottom of a coking layer, so that the coke loses the carbon content in the surface molten state, the temperature of the coke is reduced, and the coke with the ash-coated surface is formed. The coke then transitions from the coking layer to the cooling layer. The water gas reaction is the basis for the coking layer to be converted into a cooling layer (the gas after the reaction mainly comprises unreacted steam, a large amount of hydrogen, a large amount of carbon dioxide and a small amount of carbon monoxide), and the heat released by the conversion reaction further heats the coal to enable the coal to reach a surface melting state, wherein the temperature of the surface melting state exceeds the temperature required by some coking (the temperature can be even higher than the temperature reached by the traditional coking method, and can be controlled to be close to the ash melting point of the coal, and compared with the existing coking method, the method can refine coke with higher quality).

The main reaction formula is as follows:

CO+H₂0(g)＝CO₂+H₂(exothermic reaction at high temperature).

The temperature of the reacted gas is also raised equally at the same time, and the reacted gas is pushed by the pressure to move upwards to separate from the coking layer.

When the temperature in the coking layer is increased to 700-1000 ℃, the semicoke mainly releases gas, the carbon network continues to be condensed, the volume is reduced, the coke quality is hardened, and porous coke is formed. At this point, no liquid phase of the pyrolysis product has occurred. Due to the shrinkage of the semicoke, the temperature and the heating rate of each point are different, so that the shrinkage and the shrinkage rate are uneven, and coke cracks are generated to form coke. The coke continues to descend, a certain amount of water gas reaction is carried out between the lower part of the coking layer and the steam in the ascending gas, so as to reduce the temperature and form a cooling layer,

(3) the high-temperature gas out of the coking layer ascends in the coke oven and enters the dry distillation layer, and the coal in the dry distillation layer is heated to reduce the temperature of the coal.

(4) After entering the dry distillation layer, when the temperature of the dry distillation layer is between 350 and 550 ℃, coal begins to coke, macromolecules of the coal are violently decomposed in the coking process, and the broken side chains are continuously cracked, wherein the small molecular weight is in a gas state, the moderate molecular weight is in a liquid state, the large molecular weight and infusible components are in a solid state, and three phases which mutually permeate form a colloid. The caking property of coal is strong and weak, and depends on the amount of colloidal substances, fluidity and thermal stability. And when the temperature is continuously increased to 450-550 ℃, further decomposing the liquid-phase product, separating out a part of the liquid-phase product in a gaseous state, gradually thickening the rest part of the liquid-phase product, integrating the rest part of the liquid-phase product with the dispersed solid-phase particles, and finally performing polycondensation and solidification to form the semicoke.

In the process, the gaseous product escapes through the colloid, creating expansion pressure, which binds the solid particles more firmly. The gaseous products accumulated in the colloids form pores.

(5) The gas continuously goes out of the dry distillation layer and goes upwards to the drying layer, the coal in the drying layer is heated, the temperature of the coal is further reduced, and the coal continuously goes upwards and is discharged out of the coke oven from the outlet of the coke oven.

(6) The gas discharged from the coke oven enters a tail gas treatment and recovery system (the prior art) through an exhaust pipe to recover waste heat, useful gas and waste, the temperature of the gas after the waste heat recovery is further reduced and is slightly higher than the normal temperature (steam condensate water enters a cooling process along with the gas to become compensation water in the cooling process), the gas enters a purification process (the same as the prior purification process) in the tail gas treatment and recovery system, impurities such as dust and the like are removed through various cleaning and different methods, then benzene, phenol, sulfur, tar and other by-products, carbon dioxide products (for example, a pressure swing adsorption method is used) and two useful gases such as carbon monoxide and hydrogen can be obtained, and the useful gases are applied (for example, the methanol production process is put into, so that not only the methanol product is obtained, but also the hydrogen with the largest yield is purified).

(7) The coke refined at high temperature descends under the action of a coke oven grate to reduce the temperature of the cooling layer, and continues to descend to a cooling box to be cooled in hot water in the cooling box, and meanwhile, the ash on the surface of the coke is damaged due to different shrinkage rates when meeting cold, and the ash is washed away in water; the coke in the cooling tank is intermittently drawn out, and hot water is recovered after the coke is cooled by hot water in the past.

(8) Steam generated in the cooling process in the cooling box rises into a cooling layer in the coke oven, generates a small amount of water gas generation reaction with incandescent coal in the cooling layer, and is mixed with main stream gases of carbon monoxide and water vapor to continuously ascend.

(9) The coal after finishing the coal dressing work enters a charging hopper at the upper part of the coke oven through a transfer device, then enters the coke oven from a feeding hole under the control of the charging hopper to supplement the coal in the oven body and become a drying layer of the coke oven, the coal in the drying layer is influenced by the temperature rise of gas from bottom to top to evaporate water and gradually rise to the temperature of more than 300 ℃, because the grate below the coke oven continuously moves downwards under the action of rotation of the grate, a dry distillation layer, a coking layer and a cooling layer are sequentially formed in the continuous downward movement, and in the process, the coal contacts with the rising steam to generate water gas reaction, the temperature is further reduced, meanwhile, the shift reaction is generated in the coking layer, and finally, the coal reaches the bottom of the oven and enters a cooling box, the contact temperature of the coke and hot water in the cooling tank is reduced, the hot water is heated to generate steam to go upwards, the coke in the cooling tank is discharged, the discharged hot water is recycled, and the coke is cooled to form coke.

In the whole reaction process, oxygen atoms of steam and carbon monoxide in the whole coking process do not react with aromatic condensed rings in coal, do not react with macromolecules connected with side chain heterocycles and functional groups around the oxygen atoms, and do not react with macromolecules decomposed by heating coal and other all decomposed gases and liquids; but also does not react with oxygen atoms in the carbon dioxide, otherwise, the carbon dioxide in the past 'earth kiln' can not be refined into coke at all. Therefore, the oxygen-free condition of the coke oven is met, the conversion reaction is generated, the temperature is increased, and the high-temperature condition of the coke oven is met. So that the coking reaction can smoothly occur.

The method of the invention has the following innovation and advantages in application:

firstly, the design of the invention combines the useful gas generated by coking with the carbon dioxide discharged by coking, and the process of recovering the useful gas naturally needs to remove the carbon dioxide, so the process of removing the carbon dioxide is not only the process of recovering the useful gas, but also the process of implementing environmental protection on the carbon dioxide! The method is skillfully integrated, and achieves multiple targets of environmental protection, coking and chemical raw material gas production. The mode of releasing heat by the carbon monoxide shift reaction is adopted to achieve the self-heating effect (the process of recovering tail gas belongs to the prior art and is not described any more).

The gas thus produced by the coke oven comprises: carbon dioxide, carbon monoxide, hydrogen, steam, benzene, phenol and other harmful gases, and a small amount of dust, tar and sulfide. Thus all these harmful gases as well as small amounts of dust, tars, sulphides are easily removed or recovered. The rest carbon dioxide, carbon monoxide and hydrogen are high-quality industrial raw materials. The carbon dioxide can be completely recycled to achieve the excellent effect of zero emission and obtain the carbon dioxide product. The whole coking process can realize zero industrial gas emission!

Secondly, in terms of heat utilization efficiency: the result of this "self-heating" mode of the present invention is: self-heating, self-absorption or self-heating, and mutual 'co-heating'. The generated high-temperature gas preheats the coal above along with the ascending of the gas in the coke oven, and the temperature of the gas out of the coke oven is about 300 ℃, even lower. The distance between the heat source and the heat receiver is short. The heat spreading means is mainly conduction. Therefore, the heat utilization rate in the coke oven except the very little heat emitted by the oven body almost reaches one hundred percent; the distance between the heat source and the heated body of the combustion chamber type coke oven is from the combustion chamber to the center of the coke oven, the heat transmission mode is conduction and radiation, and the heat in the combustion chamber exists even in a convection mode. On the other hand, there is a large heat loss due to the heating with the air flow fluid.

Thus, we can use another idea to compare and account for the heat usage characteristics of the two furnaces: the method of the invention is equivalent to providing a heat source with the outlet gas temperature of about 300 ℃ to obtain the coke result of 1000 ℃, and the method of the combustion chamber type coke oven can obtain the coke result of 1000 ℃ by providing a heat source with the outlet gas temperature of more than 1000 ℃. And finally, waste heat characteristic and recovery: the waste heat of the invention is characterized in that the temperature of the outlet gas is about 300 ℃, and the outlet gas contains about 40% of steam before reaction. Characterized by low grade heat recovery. The combustion chamber type coke oven is used for recovering high-grade gas heat with the temperature of more than 1000 ℃. (it is also clear that the combined power generation of a coking plant is actually because of too much waste heat, and that combined power generation is actually thermal power generation today and in the future, where environmental protection and clean energy are highly advocated).

Third, will a shift reaction occur? The shift reaction of the shift section in industrial scale must be carried out in the presence of a catalyst, and the most critical and most problematic aspect of the present invention would be: will a shift reaction occur as desired? The answer is affirmative-exactly ok! This can be introduced in two ways:

1. from the reaction mechanism: the carbon atoms after high temperature become active and compete for oxygen atoms with the carbon atoms in the carbon monoxide and hydrogen atoms in the water vapor, the bonding of the carbon monoxide molecules is more stable than that of water molecules, and on the other hand, the carbon atoms in the carbon monoxide still compete for the oxygen atoms to become carbon dioxide! The result of such a competition is therefore that this reversible reaction of the shift reaction takes place! So that the carbon in the high temperature state is not a catalyst for the shift reaction but rather a catalyst! Or the carbon in high temperature state is a special, high-efficiency and excellent catalyst for the shift reaction of carbon monoxide and water vapor!

2. An abnormal phenomenon exists in a batch furnace for synthesizing ammonia, and the abnormal phenomenon can prove that the shift reaction can occur under the high-temperature carbon environment, and the abnormal phenomenon is as follows: the carbon dioxide concentration of the gas produced by the upward blowing is much higher than that of the gas produced by the downward blowing! (the unusual phenomenon is because the upper blowing gas is blown after the air blowing, and the lower blowing gas is blown after the air blowing, the higher the furnace temperature, the lower the carbon dioxide produced, the upper blowing gas is obviously at a higher temperature than the lower blowing gas, so that it seems that the lower the carbon dioxide produced by the upper blowing gas is, the same as the lower blowing gas!)

It will be appreciated that this problem must be carried out in two steps: the first step is as follows: the formation of the "oxide layer" is correctly recognized. Here we must also subvert the previous knowledge of the oxide layer (the guidance in professional teaching materials is that the carbon is formed by burning in oxygen in the blowing stage): the oxidation layer is formed by the self-heating red-turning of the heat released by the shift reaction of carbon monoxide and steam in the coal gas generated by the reduction layer in the upward blowing gas making process in the high-temperature carbon in the dry distillation layer. This can be appreciated from one point: between the oxide layer and the dry distillation layer, the difference is neat, clear and distinct like knife carving! Even a coal rod, half black and half red, or a coal block, half black and half red. The two states are clearly and clearly distinguished like lines, and the red part is uniform in color without distinction! This is a characteristic feature of the "concentration response"! It is to be understood that the reaction of gas generation in the gas furnace is a concentration reaction, and the shift reaction of carbon monoxide and steam is also a concentration reaction. Of course, the reaction in the blowing stage is also a concentration reaction, and then a question is asked: is also why the difference between the reduction layer and the oxidation layer in the blown state is large? The reduction layer is compact, molten, high-strength and bright red, while the oxidation layer is red in a preheating state and has large natural stacking gaps. Can oxygen pass through a dense, molten, and reactive carbon environment and go forward to react with carbon atoms in an oxide layer that is at a much lower temperature and is not dense and reactive? Not to say how is the possibility that excess oxygen in the reduction layer would form an oxide layer in the past? Then do you say that the concentration of 0.2% oxygen in the gas is determined by the high temperature reduction layer or the low temperature oxidation layer? Therefore, the formation of the oxide layer is most reasonable only in the view of the shift reaction, out of two possible views of the formation of the blowings and the formation of the shift reaction.

If these are not enough to be believed, then comparing the difference between a batch furnace and a gas furnace with total up-blow makes it possible to know: the reducing layers of both furnaces have what is known as an "oxide layer" on top, but the lower side of the reducing layer is different: the ash layer without red fire color is arranged under the reduction layer of the full-upblow gas furnace, a red-red layer is arranged between the reduction layer of the intermittent furnace and the ash layer (sometimes, the layer is very difficult to be seen when the furnace condition is controlled particularly well, the carbon residue quantity of the furnace is very low under the furnace condition, sometimes, a little red layer is arranged under the reduction layer of the full-upblow gas furnace, but the red layer can be ignored compared with the red layer of the intermittent furnace), the method is characterized in that! This is of course a result of the shift reaction occurring when the down-blowing is carried out in a batch furnace!

The second step is that: the phenomenon that the carbon dioxide of the upward blowing gas is larger than that of the downward blowing gas is caused. This phenomenon is difficult to detect for otherwise normal batch furnace production, as they are not very different, but are so small that they are difficult to distinguish. Because the formation of each layer of the batch furnace can not be correctly known and the theoretical guidance is not correct, the wrong process is adopted in the actual work, namely the steam pressure of the batch furnace entering the furnace is lower! Due to this index being low, the height area covered with steam during gas production cannot include all the height areas generated during blowing. In this way, in the process of blowing the gas, the gas-water-gas generation reaction in which the temperature is lowered cannot be performed in the portion where the steam cannot cover the upper portion of the reduction layer, but rather, the shift reaction occurs because the gas of the water-gas generation reaction to be generated below passes through this portion because of the high concentration of carbon monoxide and water vapor. Thus, the temperature can not be reduced during the temperature reduction, but is increased! This forms a more specific hierarchy! This layer is hard and high temperature. Similarly, the transition layer has the same tendency of forming the layer when downward blowing is carried out, but the hardness and the integrity of the layer are not allowed by the control of the furnace condition, and the hard whole is damaged by the grate. Therefore, the amount of the conversion reaction generated during the downward blowing is far less than that of the upward blowing, and the phenomenon that the carbon dioxide in the upward blowing gas is far greater than that in the downward blowing gas occurs.

The temperature range of coal with this catalyst function is proved from the fact that the coal in the black state in the dry distillation layer can still cause the shift reaction to occur and turn itself into a red oxide layer! Thus, the range is around 500 degrees celsius, and thus the present invention is feasible using a carbon monoxide and steam shift reaction approach.

Fourthly, reaction and control: the standard gas source of the invention is water gas which is blown from the top by pure oxygen and steam. On the one hand, this gas source has a large amount of carbon monoxide, up to more than 60% (dry gas). The characteristics of high content of carbon monoxide and low carbon dioxide (dry gas is 2-5%) are favorable for the forward reaction of the carbon monoxide shift reaction, and the characteristics of low hydrogen (slightly higher than 30%) are unfavorable for the reverse reaction of the carbon monoxide shift reaction. And the gas source has a certain amount of steam (about 20% of gas components, and the water-carbon ratio, namely the water vapor/carbon monoxide, is about 6-8/10) which can be directly utilized. On the other hand, if the steam is not properly distributed in the gas furnace, the gas of the gas source can also generate a large amount of shift reaction in the gas furnace, so that the operation can be carried out without adding steam or only by adding a small amount of steam under the condition that the cooling box in the coke oven generates steam, and the water-carbon ratio before the reaction in the coke oven is controlled to be 1-2.

Fifthly, emphasis and difficulty: since the shift reaction is very fast and the solution of the invention will be produced under pressure (although the pressure is not very high), it is necessary to prevent the coke bed from reacting too much, and the presence of steam in the gas, which would cause caking of the coke bed. The amount of gas fed into the furnace is controlled. The feature that the reaction rate is lower as the temperature of the shift reaction is higher is also advantageous for controlling this condition; the shift reaction speed is very fast, so that the coking layer is very thin, the phenomenon of furnace collapse and carbon flow occurs, and the production fluctuation is too large, so that the proportion of the steam to the carbon monoxide needs to be strictly controlled.

The invention has the following advantages in implementation;

1. the system is combined with the existing tail gas treatment and recovery system, the zero emission of greenhouse gas carbon dioxide can be realized, carbon dioxide products are obtained, and the zero emission of industrial harmful gases is realized.

2. The heat utilization rate is greatly improved.

3. Because of the very fast shift reaction rate and the production under pressure, the coke ovens are no longer conventional bulky products. This is advantageous for retrofitting, construction and equipment maintenance.

4. The useful gas is upgraded, and the enterprise development is facilitated.

5. The coking temperature obtained by the method of the invention can be higher than that of the traditional coking method, and is beneficial to improving the product quality.

6. The production intensity and the coking time can be adjusted and controlled.

7. The granularity of the coal and the proportion of different coal qualities can be greatly adjusted.

8. Has continuous production characteristics.

In conclusion, the coking enterprises can be prompted to achieve the environment-friendly aim of zero emission as far as possible without emitting any industrial harmful gas into the air, especially the carbon dioxide as a greenhouse gas in the production of the enterprises, and the carbon dioxide product is obtained by changing waste into valuable; the heat utilization rate in production can be greatly improved, and the economic benefit is increased; the invention is an upgrade to the useful gas produced by coking at the same time, the former coke oven only passively produces a small amount of carbon monoxide and a small amount of hydrogen, but the invention actively produces a large amount of hydrogen and a small amount of carbon monoxide, and is a conscious creation of chemical raw material gas, so that the invention can carry out the transformation upgrade of the industry according to the above; the method of the invention can achieve multiple controllable items: the process can be adjusted according to different coal quality characteristics to control different coking times, the process can be adjusted according to the quality requirements of different cokes to control different coking maximum temperatures, the process can be adjusted according to actual requirements to control the production intensity, and the coal granularity and the coal variety proportion can be greatly adjusted.

The embodiments of the present invention are disclosed as the preferred embodiments, but not limited thereto, and those skilled in the art can easily understand the spirit of the present invention and make various extensions and changes without departing from the spirit of the present invention.

Claims

1. A coke refining method comprises introducing a mixed gas of carbon monoxide and steam into a coking layer to generate shift reaction heat release and promote rapid coking; the carbon monoxide content of the mixed gas of carbon monoxide and water vapor is more than 60 percent according to the volume ratio;

in the process, the coals in the coke oven are sequentially stacked from bottom to top, and sequentially comprise a cooling layer, a coking layer, a drying layer and a dry distillation layer from bottom to top;

during ventilation, the mixed gas of carbon monoxide and steam is introduced into the coking layer to carry out shift reaction and release heat and promote quick coking, and high-temperature gas generated after the shift reaction of carbon monoxide and steam in the coking layer at the bottom layer upwards sequentially passes through the dry distillation layer and the drying layer and is discharged out of the furnace body;

2. The coke refining process of claim 1, wherein: coal in the coke oven is stacked from bottom to top in sequence, and high-temperature gas generated after the shift reaction of carbon monoxide and water vapor in the coking layer at the bottom layer is discharged out of the oven body after passing through the dry distillation layer and the drying layer in sequence.

3. The coke refining process of claim 1, wherein: before entering the coking layer, the mixed gas of carbon monoxide and steam contacts with coke in the cooling layer to cool the coke, and then the temperature of the mixed gas is raised before entering the coking layer.

4. A coke refining furnace, using the method as claimed in claim 1, which comprises a furnace body, and is characterized in that a grate is arranged at the bottom in the furnace body, the grate is conical and hollow inside, an air channel is arranged on the side wall of the grate, an air inlet communicated with an external air source is arranged at the bottom, and mixed gas of steam and carbon monoxide enters the cavity inside the grate from the air inlet and then is discharged from the air channel;

5. The coke refining furnace of claim 4, wherein: and a cooling box communicated with the feed opening is arranged outside the furnace body, cooling water is filled in the cooling box, and coke in the cooling layer enters the cooling box for cooling.

6. The coke refining furnace of claim 5, wherein: the bottom of the cooling box is provided with a coke outlet.

7. The coke refining furnace of claim 4, wherein: the inner wall of the furnace body is provided with a heat-preservation refractory brick lining layer.

8. The coke refining furnace of claim 4, wherein: the top of the furnace body is provided with a feed inlet.

9. The coke refining furnace of claim 4, wherein: the furnace grate comprises a furnace wall at the bottom and a conical body positioned at the top of the furnace wall, an inner cavity of the furnace wall is communicated with an inner cavity of the conical body, and the diameter of the furnace wall is smaller than that of the conical bottom of the conical body.

10. The coke refining furnace of claim 9, wherein: the furnace wall can rotate and drive the cone-shaped bodies to rotate synchronously.