CN110564473A

CN110564473A - Preparation method of gasification formed coke for Lurgi furnace

Info

Publication number: CN110564473A
Application number: CN201910780067.4A
Authority: CN
Inventors: 李昌伦; 谭代福; 王进昌; 张一波; 魏亚军; 刘碧武; 韩世良; 刘伟
Original assignee: Shanxi Lushui River Is Pacified Coal-Based Synthetic Oil Co Ltd; Shanxi Luan Mining Group Co Ltd
Current assignee: Shanxi Lushui River Is Pacified Coal-Based Synthetic Oil Co Ltd; Shanxi Luan Mining Group Co Ltd
Priority date: 2019-08-22
Filing date: 2019-08-22
Publication date: 2019-12-13

Abstract

the invention relates to the technical field of coal gasification production, and discloses a preparation method of gasification formed coke for a Lurgi furnace; taking coal dust with the particle size of less than 3mm as a raw material, mixing a coal gasification catalyst with the coal dust, and then adding an adhesive to obtain a mixture, wherein the weight of the adhesive is 3-12% of that of the coal dust; pressing graphite into blocks, and bonding the mixture and the graphite together through carbonization, wherein the carbonization heating rate is 3-10 ℃/min, the final temperature is 800-900 ℃, and the constant temperature time is 1-2 hours; the method takes graphite as a carrier, effectively reacts the formed coke, reduces coal ash, reduces the difficulty of tail water treatment, and can improve the coal gasification conversion efficiency, and the prepared formed coke has the characteristics of high mechanical strength, high thermal stability and high reactivity.

Description

Preparation method of gasification formed coke for Lurgi furnace

Technical Field

The invention relates to the technical field of coal gasification production, in particular to a preparation method of gasification formed coke for a Lurgi furnace.

Background

The coal gasification technology is a core technology for realizing clean conversion and utilization of coal, and the coal can be converted into clean energy and chemical gas products which are easier to utilize through the gasification process. The crushed coal pressurized fixed bed gasification technology represented by Lurgi gasification has the advantages of high gasification thermal efficiency, low oxygen consumption and synthesis gas CH₄Content and H₂the characteristics of high CO and the like are widely applied in China. However, due to the fact that the price of lump coal is increased year by year due to insufficient supply, the production cost of Lurgi furnace users is increased continuously, and the profit of enterprises is almost completely pushed. The method for replacing high-price lump coal by using low-price pulverized coal after molding is generally considered to be an effective way for solving the problem, but the pulverized coal is used in the Lurgi gasifier pressure gasification process, so that the energy consumption is high, the coal ash amount in the environment is large, and the difficulty in tail water treatment is increased.

Disclosure of Invention

The invention overcomes the defects in the prior art, and provides a preparation method of gasification formed coke for a Lurgi furnace.

The invention is realized by the following technical scheme.

A preparation method of gasification formed coke for a Lurgi furnace comprises the following steps:

a) Taking coal dust as a raw material, and crushing the coal dust to a particle size of less than 3 mm.

b) Mixing a coal gasification catalyst with the coal powder, adding an adhesive, and uniformly stirring and mixing to obtain a mixture, wherein the weight of the adhesive is 3-12% of that of the coal powder.

c) Pressing graphite into blocks, and bonding the mixture and the graphite together through carbonization, wherein the carbonization heating rate is 3-10 ℃/min, the final temperature is 800-900 ℃, and the constant temperature time is 1-2 hours.

Preferably, the coal gasification catalyst is a vanadium-based coal gasification catalyst or an alkali carbonate-based coal gasification catalyst.

Preferably, the binder is any one of waste clay, asphalt and dust-containing tar.

Preferably, the adhesive is a mixture of waste clay, asphalt and dust-containing tar in a weight ratio of 3-8:5-8: 1-2.

preferably, the mixture is mixed with graphite, pressed into a block and carbonized.

Preferably, the pressed blocks are pressed into ellipsoids by a double-roller press.

Preferably, the carbonization heating rate is 5 ℃/min, the final temperature is 850 ℃, and the constant temperature time is 1.5 hours.

Compared with the prior art, the invention has the beneficial effects that.

The invention relates to a processing method of gasification formed coke for a Lurgi furnace, which takes graphite as a carrier to effectively react the formed coke, thereby reducing energy consumption, particularly reducing coal ash, greatly reducing the difficulty of tail water treatment, and taking the pulverized coal as one of carriers of a gasification catalyst, improving the effective loading capacity of the catalyst, improving the catalytic effect of the catalyst, and further improving the conversion efficiency of coal gasification. Wherein, the solid waste and other coal chemical industry byproducts generated in the coal-to-liquid production process are used as the adhesive, and the adhesive has the characteristics of low price and environmental friendliness. The formed coke prepared by the process has the characteristics of high mechanical strength, high thermal stability and high reaction activity.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more clearly apparent, the present invention is further described in detail with reference to the embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. The technical solutions of the present invention are described in detail below with reference to examples, but the scope of protection is not limited thereto.

Example 1

a) The raw materials are selected from screened coal produced in Luyuyuwu coal industry: sieving the coal powder, and crushing the coal under the sieve with the particle size of 5mm until the particle size is less than 3 mm.

b) Mixing an alkali metal carbonate coal gasification catalyst accounting for 5 percent of the weight of coal powder with the coal powder, and then adding 10 percent of a bonding agent in steps according to the proportion: firstly, adding asphalt and waste argil, and uniformly stirring by using a double-shaft stirrer; then transferring the mixture of the coal material and the adhesive into the next double-shaft stirrer, spraying ethanol water solution to fully wet and uniformly stir; then transferring the material into a next double-shaft stirrer, adding dust-containing tar and uniformly stirring; the adhesive contains 50% of asphalt, 40% of waste clay and 10% of dust-containing tar.

c) Pressing graphite into blocks of 50x50x50cm, airing and drying the coal material obtained through the steps, and then conveying the coal material and the graphite blocks to a carbonization furnace for carbonization to bond the coal material and the graphite; the speed of carbonization temperature rise is 5 ℃/min, the final temperature is 850 ℃, and the constant temperature time is 1.5 hours.

d) and conveying the cooled formed coke to a storage bin for later use.

The waste clay is the residue of organic matters extracted from spent clay filler used for filtering oil products in the Fischer-Tropsch synthesis oil process. The asphalt related in the method is the asphalt with the softening point of more than 180 ℃, the asphalt is used as the adhesive after being crushed to 0.5mm, the dust-containing tar is the byproduct of the Lurgi gasifier, and the main components are coal tar and coke powder particles. The dust-containing tar is in a liquid sticky state.

Example 2

b) Mixing a vanadium-based coal gasification catalyst accounting for 6 percent of the weight of the coal powder with the coal powder, and then adding 12 percent of a bonding agent in steps according to the proportion: firstly, adding asphalt and waste argil, and uniformly stirring by using a double-shaft stirrer; then transferring the mixture of the coal material and the adhesive into the next double-shaft stirrer, spraying ethanol water solution to fully wet and uniformly stir; then transferring the material into a next double-shaft stirrer, adding dust-containing tar and uniformly stirring; the adhesive contains 60% of asphalt, 35% of waste clay and 5% of dust-containing tar.

c) Pressing graphite into blocks of 50x50x50cm, airing and drying the coal material obtained through the steps, and then conveying the coal material and the graphite blocks to a carbonization furnace for carbonization to bond the coal material and the graphite; the speed of carbonization temperature rise is 10 ℃/min, the final temperature is 800 ℃, and the constant temperature time is 2 hours.

d) and conveying the cooled formed coke to a storage bin for later use.

Example 3

b) Mixing a vanadium-based coal gasification catalyst accounting for 4% of the weight of coal powder with the coal powder, and then adding 3% of a binder in steps according to the proportion: firstly, adding asphalt and waste argil, and uniformly stirring by using a double-shaft stirrer; then transferring the mixture of the coal material and the adhesive into the next double-shaft stirrer, spraying ethanol water solution to fully wet and uniformly stir; then transferring the material into a next double-shaft stirrer, adding dust-containing tar and uniformly stirring; the adhesive contains 70% of asphalt, 25% of waste clay and 10% of dust-containing tar.

c) Pressing graphite into blocks of 50x50x50cm, airing and drying the coal material obtained through the steps, and then conveying the coal material and the graphite blocks to a carbonization furnace for carbonization to bond the coal material and the graphite; the speed of carbonization temperature rise is 3 ℃/min, the final temperature is 900 ℃, and the constant temperature time is 1 hour.

d) And conveying the cooled formed coke to a storage bin for later use.

example 4

b) Mixing an alkali metal carbonate coal gasification catalyst accounting for 5 percent of the weight of coal powder with the coal powder, and then adding 10 percent of a bonding agent in steps according to the proportion: firstly, adding asphalt and waste argil, and uniformly stirring by using a double-shaft stirrer; then transferring the mixture of the coal material and the adhesive into the next double-shaft stirrer, spraying ethanol water solution to fully wet and uniformly stir; then transferring the material into a next double-shaft stirrer, adding dust-containing tar and uniformly stirring; the adhesive contains 80% of asphalt, 15% of waste clay and 5% of dust-containing tar.

d) and conveying the cooled formed coke to a storage bin for later use.

Test example 1

Measuring method

1. The test method for Drop Strength (DS) of the molded coal was performed according to the method specified in MT/T925.

2. The test method for the thermal stability (BST +13) of the briquettes was carried out according to the method specified in the industry Standard MT/T924.

Wherein, the adhesive is prepared according to the following ratio (weight percent) in table 1:

Taking 100 parts of the coal dust mixed with the catalyst obtained in the step b in the example 1, adding a binder with the corresponding percentage of the weight of the coal dust according to the following table, carbonizing the coal dust and the graphite block to prepare formed coke, and measuring the falling strength and the thermal stability of the formed coal, wherein the results are shown in the following table:

By taking graphite as a carrier, the formed coke is effectively reacted, the energy consumption is reduced, particularly, the coal ash is reduced, the difficulty in tail water treatment is greatly reduced, and the pulverized coal is also used as one of carriers of the gasification catalyst, so that the effective loading capacity of the catalyst can be improved, the catalytic effect of the catalyst is improved, and the coal gasification conversion efficiency can be improved. Wherein, the solid waste and other coal chemical industry byproducts generated in the coal-to-liquid production process are used as the adhesive, and the adhesive has the characteristics of low price and environmental friendliness. The formed coke prepared by the process has the characteristics of high mechanical strength, high thermal stability and high reaction activity.

while the invention has been described in further detail with reference to specific preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. The preparation method of the gasification formed coke for the Lurgi furnace is characterized by comprising the following steps:

a) Taking coal dust as a raw material, and crushing the coal dust to a particle size of less than 3 mm;

b) Mixing a coal gasification catalyst with the coal powder, adding an adhesive, and uniformly stirring and mixing to obtain a mixture, wherein the weight of the adhesive is 3-12% of that of the coal powder;

2. The method for preparing gasification formed coke for lurgi furnace as claimed in claim 1, wherein the coal gasification catalyst is vanadium-based coal gasification catalyst or alkali carbonate-based coal gasification catalyst.

3. The method for preparing the gasification formed coke for the lurgi furnace as claimed in claim 1, wherein the binder is any one of waste clay, asphalt and dust-containing tar.

4. The method for preparing the gasification formed coke for the lurgi furnace as claimed in claim 1, wherein the binder is a mixture of spent bleaching clay, asphalt and dust-containing tar in a weight ratio of 3-8:5-8: 1-2.

5. The method for preparing the gasification formed coke for the Lurgi furnace as claimed in claim 1, wherein the mixture is mixed with graphite, pressed into blocks and carbonized.

6. The method for preparing the gasification formed coke for the Lurgi furnace as recited in claim 1 or 5, wherein the pressed blocks are formed into ellipsoids by a double roll machine.

7. the preparation method of the gasification formed coke for the Lurgi furnace as claimed in claim 1, wherein the carbonization temperature rise rate is 5 ℃/min, the final temperature is 850 ℃, and the constant temperature time is 1.5 hours.