阅读说明：本技术 水煤浆和水煤气的制备方法及其应用 (Preparation method and application of coal water slurry and water gas ) 是由 冯长志 鲍金源 邱敏 宁英辉 姜兴剑 张清海 李培丰 卢利飞 雷聪 于 2021-08-18 设计创作，主要内容包括：本发明涉及废物处理领域,公开了一种使用煤气化黑水、污泥水和有机废水制备水煤浆和水煤气的方法及其应用。本发明的水煤浆的制备方法包括：1)将煤气化黑水与第一絮凝剂进行第一混合后再进行第一静置沉降得到灰水和细渣的步骤；2)将污泥水与第二絮凝剂进行第二混合后再进行第二静置沉降得到浓污泥水和稀污泥水的步骤；3)将颗粒煤、稀污泥水、有机废水、水煤浆添加剂、灰水和细渣进行研磨得到水煤浆的步骤,其中,所述污泥水为生化污泥水。该方法降低了废弃物的处理成本,实现对煤气化黑水、污泥和有机废水的资源化利用,并且可以提供高质量的水煤浆和水煤气。(The invention relates to the field of waste treatment, and discloses a method for preparing coal water slurry and water gas by using coal gasification black water, sludge water and organic wastewater and application thereof. The preparation method of the coal water slurry comprises the following steps: 1) performing first mixing on coal gasification black water and a first flocculating agent, and then performing first standing and settling to obtain grey water and fine slag; 2) performing second mixing on the sludge water and a second flocculating agent, and then performing second standing and settling to obtain concentrated sludge water and dilute sludge water; 3) grinding granular coal, dilute sludge water, organic wastewater, a coal water slurry additive, grey water and fine slag to obtain the coal water slurry, wherein the sludge water is biochemical sludge water. The method reduces the treatment cost of the waste, realizes the resource utilization of the coal gasification black water, the sludge and the organic wastewater, and can provide high-quality coal water slurry and water gas.)

1. A preparation method of coal water slurry is characterized by comprising the following steps:

1) performing first mixing on coal gasification black water and a first flocculating agent, and then performing first standing and settling to obtain grey water and fine slag;

2) performing second mixing on the sludge water and a second flocculating agent, and then performing second standing and settling to obtain concentrated sludge water and dilute sludge water;

3) grinding the granular coal, the dilute sludge water, the organic wastewater, the coal water slurry additive, the grey water and the fine slag to obtain the coal water slurry,

wherein the sludge water is biochemical sludge water.

2. The method according to claim 1, wherein in step 1), the coal gasification black water contains 0.1-10 mass% of coal slag, and the particle size of the coal slag is 1-2000 μm;

preferably, the conditions of the first mixing include: the mixing temperature is 5-50 ℃, and the mixing time is 2-10 s;

preferably, the conditions of the first standing sedimentation comprise: standing at 5-50 deg.C for 3-5 hr;

preferably, the grey water has a pH value of 7 to 9;

preferably, the first flocculating agent is a cationic polyacrylamide high molecular polymer.

3. The method according to claim 1, wherein in step 2), the solid content of the sludge water is 0.1 to 5 mass%;

preferably, the conditions of the second mixing include: the mixing temperature is 5-50 ℃, and the mixing time is 5-20 s;

preferably, the second standing sedimentation condition comprises: standing at 5-50 deg.C for 3-5 hr;

preferably, the second flocculating agent is one or more of polyacrylamide high molecular polymer, nonionic polyacrylamide and polyaluminium chloride.

4. The method according to claim 1, wherein in step 2), the solid content of the concentrated sludge water is 1-5 mass%;

preferably, the solid content of the dilute sludge water is 0.1 to 2 mass%.

5. The method according to claim 1, wherein in step 3), the particle size of the particulate coal is 20mm or less;

preferably, the COD of the organic wastewater is 1-100000 mg/L;

preferably, the pH of the organic wastewater is 6-9;

preferably, the coal water slurry additive is one or more of naphthalene sulfonic acid methyl condensate, sodium lignosulfonate, trisodium phosphate and cellulose.

6. The method according to claim 1, wherein in the step 3), the grinding is carried out to ensure that the particle size of particles in the coal water slurry is less than 2 mm;

preferably, the conditions of the milling include: grinding at 15-30rpm at 5-50 deg.C for 5-60 min;

preferably, the total weight of the granular coal, the dilute sludge water, the organic wastewater, the coal water slurry additive, the grey water and the fine slag is 100 percent by weight, the granular coal is 55 to 70 percent by weight, the dilute sludge water is 0.5 to 10 percent by weight, the organic wastewater is 2 to 20 percent by weight, the coal water slurry additive is 0.2 to 1 percent by weight, the grey water is 1 to 20 percent by weight, and the fine slag is 5 to 20 percent by weight;

preferably, the grinding is carried out so that the viscosity of the coal water slurry is 1300CP or less;

preferably, the grinding is carried out such that the concentration of the coal-water slurry is 58 to 70 mass%.

7. The method of any of claims 1-6, wherein the method further comprises: filtering the obtained coal water slurry, wherein the filtering is used for removing particles with the particle size of more than or equal to 3000 mu m;

preferably, the method further comprises: and removing iron filings from the obtained coal water slurry.

8. A method of producing water gas, the method comprising: the coal-water slurry obtained by the method of any one of claims 1 to 7 is pressurized and then injected into a gasification furnace to react with oxygen.

9. The method of claim 8, the conditions of the reaction comprising: the temperature is 1000-;

preferably, the ratio of the volume of the coal water slurry to the volume of the oxygen gas is 1m³：460-500m³。

10. Use of a process according to any one of claims 1 to 9 in the preparation of a water-coal-slurry and/or water-gas.

Technical Field

The invention relates to the field of waste treatment, in particular to a method for preparing coal water slurry and water gas by using coal gasification black water, sludge water and organic wastewater and application thereof

Background

Coal gasification is a technology capable of efficiently and cleanly utilizing coal, and the coal is gasified to obtain crude synthesis gas which becomes an important raw material source of C1 chemical industry. The coal water slurry is a novel coal-based fluid, has the characteristics of good fluidity, high combustion efficiency, energy conservation, environmental protection and the like, is an ideal fuel and gasification raw material for replacing oil, and has great influence on gasification due to good and bad slurry forming effect.

The gasified black water from the coal gasification flash system contains a certain amount of coal slag, and the gasified black water and a flocculating agent are mixed and then pass through a settling tank in the prior art, and then the black water with high content of fine slag at the bottom is dehydrated to obtain a filter cake with the water content of about 50 mass percent. Because the water content of the filter cake is high, the filter cake is difficult to be recycled, and the filter cake is generally sent to a slag yard for landfill treatment or is combusted and utilized after being dried. However, the filter cake has high energy consumption and high treatment cost for drying, and needs special supporting equipment, and the filter cake is generally sent to a slag yard for landfill treatment in actual production, thereby causing resource waste.

Meanwhile, besides recycling of the clear grey water at the upper part of the settling tank, about 20 mass percent of the grey water is discharged as wastewater. The content of ash water particles is about 100ppm, the pH value is 6-9, the COD is about 1000mg/L, the ammonia nitrogen is 300-500mg/L, the total alkalinity is more than 400mg/L, and the total hardness is more than 1000 mg/L. The ammonia nitrogen content of the grey water is high, and the treatment cost is high.

Disclosure of Invention

The invention aims to provide a method for preparing coal water slurry by utilizing coal gasification black water, sludge and organic wastewater and application thereof.

The invention provides a preparation method of coal water slurry, which comprises the following steps:

1) performing first mixing on coal gasification black water and a first flocculating agent, and then performing first standing and settling to obtain grey water and fine slag;

2) performing second mixing on the sludge water and a second flocculating agent, and then performing second standing and settling to obtain concentrated sludge water and dilute sludge water;

3) grinding the granular coal, the dilute sludge water, the organic wastewater, the coal water slurry additive, the grey water and the fine slag to obtain the coal water slurry,

wherein the sludge water is biochemical sludge water.

Preferably, in the step 1), the content of the coal slag in the coal gasification black water is 0.1-10% by mass, and the particle size of the coal slag is 1-2000 μm.

Preferably, the conditions of the first mixing include: the mixing temperature is 5-50 deg.C, and the mixing time is 2-10 s.

Preferably, the conditions of the first standing sedimentation comprise: the standing temperature is 5-50 ℃, and the standing time is 3-5 h.

Preferably, the grey water has a pH value of 7-9.

Preferably, the first flocculating agent is a cationic polyacrylamide high molecular polymer.

Preferably, in step 2), the solid content of the sludge water is 0.1 to 5 mass%.

Preferably, the conditions of the second mixing include: the mixing temperature is 5-50 deg.C, and the mixing time is 5-20 s.

Preferably, the second standing sedimentation condition comprises: the standing temperature is 5-50 ℃, and the standing time is 3-5 h.

Preferably, the second flocculating agent is one or more of polyacrylamide high molecular polymer, nonionic polyacrylamide and polyaluminium chloride.

Preferably, in step 2), the solid content of the concentrated sludge water is 1 to 5 mass%.

Preferably, the solid content of the dilute sludge water is 0.1 to 2 mass%.

Preferably, in the step 3), the particle size of the granular coal is 20mm or less.

Preferably, the COD of the organic wastewater is 1-100000 mg/L.

Preferably, the organic wastewater has a pH of 6 to 9.

Preferably, the coal water slurry additive is one or more of naphthalene sulfonic acid methyl condensate, sodium lignosulfonate, trisodium phosphate and cellulose.

Preferably, in the step 3), the grinding is carried out so that the particle size of particles in the coal water slurry is less than 2 mm.

Preferably, the conditions of the milling include: the grinding speed is 15-30rpm, the grinding temperature is 5-50 ℃, and the grinding time is 5-60 min.

Preferably, the total weight of the granular coal, the dilute sludge water, the organic wastewater, the coal water slurry additive, the grey water and the fine slag is 100 wt%, the granular coal is 55-70 wt%, the dilute sludge water is 0.5-10 wt%, the organic wastewater is 2-20 wt%, the coal water slurry additive is 0.2-1 wt%, the grey water is 1-20 wt%, and the fine slag is 5-20 wt%.

Preferably, the grinding is performed so that the viscosity of the coal-water slurry is 1300CP or less.

Preferably, the grinding is carried out such that the concentration of the coal-water slurry is 58 to 70 mass%.

Preferably, the method further comprises: and filtering the obtained coal water slurry, wherein the filtering is used for removing particles with the particle size of more than or equal to 3000 microns.

Preferably, the method further comprises: and removing iron filings from the obtained coal water slurry.

In a second aspect, the present invention provides a process for producing water gas, the process comprising: the coal-water slurry obtained by the method of any one of claims 1 to 7 is pressurized and then injected into a gasification furnace to react with oxygen.

Preferably, the conditions of the reaction include: the temperature is 1000 ℃ and 1400 ℃, and the pressure is 4-8 MPa.

Preferably, the ratio of the volume of the coal water slurry to the volume of the oxygen gas is 1m³：460-500m³。

In a third aspect the invention provides the use of a process according to the invention in the preparation of a water-coal-slurry and/or water-gas.

The method reduces the treatment cost of the waste, realizes the resource utilization of the coal gasification black water, the sludge and the organic wastewater, and can provide high-quality coal water slurry and water gas.

Detailed Description

The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.

The invention provides a preparation method of coal water slurry, which comprises the following steps:

1) performing first mixing on coal gasification black water and a first flocculating agent, and then performing first standing and settling to obtain grey water and fine slag;

2) performing second mixing on the sludge water and a second flocculating agent, and then performing second standing and settling to obtain concentrated sludge water and dilute sludge water;

3) grinding the granular coal, the dilute sludge water, the organic wastewater, the coal water slurry additive, the grey water and the fine slag to obtain the coal water slurry,

wherein the sludge water is biochemical sludge water.

The inventor of the invention discovers through research that the coal-water slurry is prepared by settling coal gasification black water which is common in coal chemical industry and processing the settled coal gasification black water with sludge, organic wastewater and granular coal, and can obtain high-quality coal-water slurry and realize resource utilization of the coal gasification black water.

In the invention, the biochemical sludge water can be chemical plant biochemical sludge water and/or municipal biochemical sludge water.

In the invention, the biochemical sludge water of the chemical plant refers to: the chemical plant sewage is biologically treated to degrade organic matters in the sewage, mainly comprising various bacteria and primitive organisms. For example, biochemical sludge water obtained by sewage treatment of Yulin chemical Co., Ltd.

In the invention, the municipal biochemical sludge water refers to: the sewage entering the municipal pipe network is discharged by residents in life, and the sludge water is treated by a municipal sewage treatment plant. For example, biochemical sludge water treated by a sewage treatment plant of Ullin City may be mentioned.

According to the invention, the coal gasification black water can be water containing coal slag obtained by a coal gasification flash evaporation system in coal chemical industry. The coal gasification black water may contain, for example, 1 to 15% by mass of coal slag, and the particle size of the coal slag contained therein may be, for example, 1 to 5000 μm; preferably, the content of the coal slag in the coal gasification black water is 5-10 mass%, and the particle size of the coal slag is 500-2000 μm.

According to the present invention, in order to obtain a better flocculation effect, preferably, the conditions of the first mixing include: the mixing temperature is 5-50 ℃, and the mixing time is 3-5 h; more preferably, the conditions of the first mixing include: the mixing temperature is 10-40 ℃, and the mixing time is 3-4 h. For better flocculation, preferably, the first mixing further comprises stirring.

According to the present invention, in order to allow the fine slag to be more sufficiently settled, it is preferable that the conditions of the first standing settlement include: standing at 5-50 deg.C for 3-5 hr; more preferably, the conditions of the first standing sedimentation comprise: the standing temperature is 10-40 ℃, and the standing time is 3-4 h.

According to the invention, when the pH value of the grey water is more than 7, the grey water has a modification effect on the coal water slurry, and preferably, the pH value of the grey water is 7-9; more preferably, the grey water has a pH of 8-8.5.

According to the present invention, the first flocculant is not particularly limited, and may be a flocculant generally used in the art, for example, one or more of cationic polyacrylamide high molecular polymer, nonionic polyacrylamide, and polyaluminum chloride; preferably, the first flocculating agent is cationic polyacrylamide and/or polyaluminium chloride complex cationic polyacrylamide.

The amount of the first flocculant is not particularly limited, and may be arbitrarily adjusted according to the need and the kind of the flocculant, and for example, may be set in a range of 1: 500000 in proportion; preferably, the mass ratio of the flocculating agent to the coal gasification black water is 1: 250000 and 500000.

According to the present invention, in order to facilitate the settling treatment to obtain a concentrated sludge water having a suitable sludge concentration, it is preferable that the solid content of the sludge water is 0.1 to 10 mass%; more preferably, the solid content of the sludge water is 2 to 5 mass%.

According to the present invention, in order to obtain a better flocculation effect, preferably, the conditions of the second mixing include: the mixing temperature is 5-50 ℃, and the mixing time is 1-10 h; more preferably, the conditions of the second mixing include: the mixing temperature is 10-40 ℃, and the mixing time is 5-10 h. For better flocculation, preferably, the second mixing further comprises stirring.

According to the present invention, in order to allow the sludge to be more sufficiently settled, it is preferable that the conditions of the second standing settlement include: standing at 5-50 deg.C for 3-5 hr; more preferably, the conditions of the second standing sedimentation comprise: the standing temperature is 10-40 ℃, and the standing time is 4-5 h.

According to the present invention, the second flocculant is not particularly limited, and may be a flocculant generally used in the field of wastewater treatment, and may be, for example, one or more of cationic polyacrylamide high molecular polymer, nonionic polyacrylamide, and polyaluminum chloride; preferably, the second flocculating agent is cationic polyacrylamide and/or complex cationic polyacrylamide.

The amount of the second flocculant to be used is not particularly limited, and may be arbitrarily adjusted according to the need and the kind of the flocculant, and may be, for example, a mass ratio of 1: 500000 in proportion; preferably, the mass ratio of the flocculating agent to the sludge water is 1: 250000 and 500000.

According to the invention, when the concentrated sludge water contains sludge with specific content, the prepared coal water slurry has better quality, and preferably, in the step 2), the solid content of the concentrated sludge water is 2-5% by mass; more preferably, in step 2), the solid content of the concentrated sludge water is 3 to 5 mass%.

Preferably, the solid content of the dilute sludge water is 0.1 to 2 mass%; more preferably, the solid content of the dilute sludge water is 0.5 to 2 mass%.

The method for separating the dilute sludge water and the concentrated sludge water is not particularly limited, and a method generally used in the art, for example, a settling tank may be used for separation.

According to the present invention, in order to facilitate grinding, it is preferable that the particle size of the granular coal in step 3) is 20mm or less; more preferably, the particle size of the particulate coal is 1 to 15 mm.

According to the invention, when the organic wastewater contains organic matters with specific content, the obtained coal water slurry has better quality, and preferably, the COD of the organic wastewater is 1-100000 mg/L; more preferably, the COD of the organic wastewater is 1-50000 mg/L; further preferably, the COD of the organic wastewater is 100-50000 mg/L; further preferably, the COD of the organic wastewater is 500-20000mg/L, and particularly preferably, the COD of the organic wastewater is 10000-20000 mg/L.

According to the invention, when the pH value of the organic wastewater is in a specific range, the organic wastewater has a modification effect on the coal water slurry, the obtained coal water slurry has better quality, and preferably, the pH value of the organic wastewater is 6-9; more preferably, the organic wastewater has a pH of 7 to 9.

As the organic waste water, various organic waste water discharged from chemical plants, from which alcohol, ether and the like have been preliminarily treated and which has a high COD content can be used. Examples thereof include: organic wastewater discharged by a methanol-to-olefin process and organic wastewater subjected to steam stripping treatment discharged by an olefin separation process. Specific examples thereof include: organic wastewater discharged by a methanol-to-olefin device of the national Ullin chemical industry Co., Ltd and organic wastewater subjected to steam stripping treatment discharged by an olefin separation device.

According to the present invention, the coal water slurry additive is not particularly limited, and may be a coal water slurry additive generally used in the field of coal chemical industry, for example, one or more of naphthalenesulfonic acid methyl condensate, sodium lignosulfonate, trisodium phosphate and cellulose, and preferably, the coal water slurry additive is naphthalenesulfonic acid methyl condensate and/or sodium lignosulfonate.

According to the invention, the grinding is used for reducing the particle size of particles in the coal water slurry, preferably, in the step 3), the grinding enables the particle size of the particles in the coal water slurry to be less than 3 mm; more preferably, the grinding is carried out to ensure that the particle size of particles in the coal water slurry is less than 2 mm; further preferably, the grinding is carried out so that the particle size of particles in the coal water slurry is 1 mu m-2 mm.

In a preferred embodiment of the invention, the particle size of the particles in the coal water slurry after grinding satisfies the following conditions: 100 percent of the powder passes through a 8-mesh sieve, 98 percent of the powder passes through a 12-mesh sieve, 75 percent of the powder passes through a 35-mesh sieve, and 25 to 35 percent of the powder passes through a 325-mesh sieve.

According to the present invention, in order to obtain a better grinding effect, it is preferable that the grinding conditions include: grinding at 15-30rpm at 5-50 deg.C for 30-60 min; more preferably, the conditions of the milling include: the grinding speed is 15-30rpm, the grinding temperature is 10-50 ℃, and the grinding time is 30-60 min.

According to the present invention, from the viewpoint of improving the properties of the resulting coal-water slurry, it is preferable that the particulate coal is 55 to 70% by weight, the diluted sludge water is 0.5 to 10% by weight, the organic wastewater is 2 to 20% by weight, the coal-water slurry additive is 0.2 to 1% by weight, the grey water is 1 to 20% by weight, and the fine slag is 5 to 20% by weight, based on 100% by weight of the total of the particulate coal, the diluted sludge water, the organic wastewater, the coal-water slurry additive, the grey water, and the fine slag; more preferably, the total weight of the granular coal, the dilute sludge water, the organic wastewater, the coal water slurry additive, the grey water and the fine slag is 100 wt%, the granular coal is 64-67 wt%, the dilute sludge water is 2-8 wt%, the organic wastewater is 5-15 wt%, the coal water slurry additive is 0.5-0.7 wt%, the grey water is 3-15 wt%, and the fine slag is 8-10 wt%.

According to the invention, when the viscosity is in a specific range, the coal water slurry is more convenient to use, and preferably, the grinding enables the viscosity of the coal water slurry to be below 1300 CP; more preferably, the grinding is performed so that the viscosity of the coal-water slurry is 300-900 CP.

According to the invention, the coal water slurry has better performance when the concentration is in a specific range, and preferably, the grinding enables the concentration of the coal water slurry to be 58-70 mass%; preferably, the grinding is carried out so that the concentration of the coal-water slurry is 62 to 65 mass%.

According to the present invention, in order to further remove particles from the coal water slurry, preferably, the method further comprises: and filtering the obtained coal water slurry, wherein the filtering is used for removing particles with the particle size being more than or equal to 3 mm.

The filtration method is not particularly limited, and may be a filtration method generally used in the chemical field, and for example, filtration may be performed using a drum screen.

According to the present invention, in order to remove the coal and the iron pieces introduced into the pulper and avoid interference with the apparatus, it is preferable that the method further comprises: and removing iron filings from the obtained coal water slurry.

The method for removing iron scrap is not particularly limited, and may be an iron removal method generally used in the chemical field, and for example, iron removal may be performed using an iron remover.

In a second aspect, the invention provides a method for preparing water gas, which comprises the step of pressurizing the water coal slurry obtained by the preparation method, spraying the pressurized water coal slurry into a gasification furnace, and reacting the pressurized water coal slurry with oxygen.

According to the present invention, preferably, the reaction conditions of the coal water slurry and oxygen include: the reaction temperature is 1200-1400 ℃, and the reaction pressure is 6-7 MPa; more preferably, the reaction temperature of the coal water slurry and the oxygen is 1240-1300 ℃, and the reaction pressure is 6.2-6.7 MPa.

When the reaction conditions are the above conditions, the reaction of the coal water slurry and oxygen to generate hydrogen and carbon monoxide is more fully carried out, and substances such as ammonia nitrogen in the coal water slurry can be harmless.

According to the present invention, it is preferable that the ratio of the mass of the coal-water slurry to the volume of the oxygen gas is 1m from the viewpoint of improving the reaction efficiency³：460-500m³(ii) a More preferably, the ratio of the mass of the coal-water slurry to the volume of the oxygen gas is 1m³：460-480m³。

In a second aspect the invention provides the use of a process according to the invention in the preparation of a water-coal-slurry and/or water-gas.

The method reduces the treatment cost of the waste, realizes the resource utilization of the coal gasification black water, the sludge and the organic wastewater, and can provide high-quality coal water slurry and water gas.

Examples

The present invention will be described in detail below by way of examples, but the present invention is not limited to the following examples.

In the following examples, the coal ash content of the coal gasification black water was 10 wt%, and the particle size of the coal ash contained was 500-2000 μm. The sludge water is provided by a sewage treatment plant of the national elm chemical industry limited company, and the solid content of the sludge water is 2-5 wt%. The organic wastewater was produced by Yulin chemical Co., Ltd, and the pH and COD of the organic wastewater used in each example are shown in Table 1.

Example 1

(1) Mixing coal gasification black water and a first flocculating agent (cationic polyacrylamide, purchased from Hezhou, China chemical industry Co., Ltd.) according to a mass ratio of 500000: 1 is mixed for 10s at the temperature of 45 ℃ and then is kept still for settling for 4h to obtain grey water and fine slag.

(2) Mixing the sludge water and a second flocculating agent (polyaluminium chloride, purchased from filter material industry Co., Ltd., of Guyi city) according to a mass ratio of 250000: 1 is mixed for 20s at the temperature of 35 ℃ and then is kept still for 5h for sedimentation, thick sludge water is obtained from the bottom of a sedimentation tank, and thin sludge water is obtained from an overflow port of the sedimentation tank.

(3) Granular coal (with the average particle size of 19mm), the thin sludge water obtained in the step (2), organic wastewater, a coal water slurry additive (the main component is sodium lignosulfonate, the solid content is more than or equal to 30 percent, and the additive is purchased from Shanghai research institute of Shenhua coal-oil chemical Co., Ltd.) and the grey water and the fine slag obtained in the step (1) are mixed according to the mass ratio of 65: 2: 5: 0.5: 17.5: 10 grinding to obtain the coal water slurry, wherein the grinding conditions comprise: the grinding speed is 25rpm, the grinding temperature is 25 ℃, and the grinding time is 50 min.

(4) Mixing the coal water slurry obtained in the step (3) with pure oxygen according to the ratio of 1m³：490m³The water gas is introduced into a gasification furnace according to the proportion and reacts at 1250 ℃ under 6.5MPa to obtain the water gas.

Examples 2 to 5

Coal water slurry and water gas were prepared in the same manner as in example 1 except that the solid content of the sludge water and the pH value and COD of the organic wastewater used and the mass ratios of the granular coal, the dilute sludge water, the organic wastewater, the coal water slurry additive, the gray water and the fine slag in step (3) were respectively values shown in Table 1.

Comparative example 1

Coal water slurry and water gas were prepared as in example 3 except that equal mass of water was used instead of sludge water.

Comparative example 2

Coal water slurry and water gas were prepared according to the method of example 3, except that water of the same quality was used instead of organic waste water.

Comparative example 3

Coal water slurry and water gas were prepared according to the method of example 3 except that water of the same quality was used in place of the sludge water, organic wastewater and fine slag.

TABLE 1

Test example 1

The concentration of the obtained coal water slurry is measured according to the method of GB/T18556.2-2008, the particle size distribution of the obtained coal water slurry is measured according to the method of GB/T18556.3-2008, and the apparent viscosity of the obtained coal water slurry is measured according to the method of GB/T18556.4-2008, and the result is shown in Table 2.

TABLE 2

As can be seen from the results in Table 2, the concentrations of the coal water slurry prepared by the method are all larger than 63%, which is at least improved by 2%, and the coal water slurry has reasonable particle size distribution and good performance.

Test example 2

The composition contents of the obtained water gas were measured by gas chromatography, and the results are shown in Table 3.

TABLE 3

The results in Table 3 show that the effective gas content of the water gas prepared by the method of the invention is more than 80%, and the gasification performance is better.

The preferred embodiments of the present invention have been described above in detail, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, many simple modifications can be made to the technical solution of the invention, including combinations of various technical features in any other suitable way, and these simple modifications and combinations should also be regarded as the disclosure of the invention, and all fall within the scope of the invention.