WO2019090455A1

WO2019090455A1 - Method for preparing ashless coal by means of co-thermal dissolution of biomass and low-rank coal

Info

Publication number: WO2019090455A1
Application number: PCT/CN2017/109652
Authority: WO
Inventors: 李显
Original assignee: 摩科瑞环保技术（苏州）有限公司
Priority date: 2017-11-07
Filing date: 2017-11-07
Publication date: 2019-05-16
Also published as: CN108064259B; CN108064259A

Abstract

Disclosed is a method for preparing an ashless coal by means of the co-thermal dissolution of biomass and a low-rank coal, the method comprising the following steps: 1) using biomass and a low-rank coal as raw materials, and mixing same before carrying out thermal dissolution using an aromatic hydrocarbon as a solvent; and 2) after thermal dissolution, extracting same while hot to obtain an extraction liquid, and after cooling, separating and removing the solvent from the extraction liquid so as to obtain the ashless coal. The raw materials used in the present invention are low-rank coals and biomasses, which extends the range of the raw materials used for preparing the ashless coal, can effectively reduce the costs of the raw materials, and has an industrial prospect for realizing the large-scale preparation of the ashless coal.

Description

Method for preparing ashless coal by biomass-low-rank coal co-heat solution

Technical field

The invention belongs to the technical field of coal chemical industry, and mainly relates to a method for preparing ashless coal by biomass-low-rank coal co-heat solution.

Background technique

Ashless coal can be used as a coking additive or directly injected into a gas turbine for combustion. The use of organic solvent hot extraction method to separate organic matter from coal to produce ashless coal is an important clean coal technology that has emerged in Japan in recent years. For example, it has been reported that by thoroughly mixing coal with organic solvents, in the 400- A process in which the slurry is extracted at a temperature of 420 ° C, and then separated into a liquid portion and a non-liquid portion, and then the liquid portion is separated into a solvent to obtain an extract. At present, the raw materials used in the preparation of ashless coal are still limited to coal, and biomass can be used as a source of energy for a wide range of sources, and can also be used for the preparation of ashless coal. However, biomass has a low energy density, a large storage volume, and high transportation costs, making it difficult to use it alone as a raw material for ashless coal.

Summary of the invention

In view of the deficiencies in the prior art, an object of the present invention is to provide a method for preparing ashless coal by biomass-low rank coal co-heat solution.

The technical solution adopted by the invention is:

A method for preparing ashless coal by biomass-low-rank coal co-heat solution, comprising the following steps:

1) using biomass and low rank coal as raw materials, mixing and then using aromatic hydrocarbons as solvent for hot solution;

2) After hot-dissolving, the extract is obtained by hot extraction, and after cooling, the solvent in the extract is separated to obtain ash-free coal.

Preferably, the biomass-low rank coal is co-heat-melted to produce ashless coal, wherein the aromatic hydrocarbon is selected from the group consisting of 1-methylnaphthalene, tetrahydronaphthalene or a combination thereof.

Preferably, the biomass-low rank coal is co-heat-melted to produce ashless coal, wherein the temperature during the hot extraction is controlled at 250-350 °C.

Preferably, the biomass-low rank coal is co-heat-melted to prepare ashless coal, wherein the extraction time is controlled to be 0.5-1 hour.

Preferably, the biomass-low rank coal is co-heat-melted to produce ashless coal, wherein the aromatic hydrocarbon comprises 1-methylnaphthalene and tetrahydronaphthalene, 1-methylnaphthalene and tetrahydronaphthalene. The mass ratio is 1.2-3.3:5.

Preferably, the biomass-low rank coal is co-heat-dissolved to prepare ashless coal, wherein the mass ratio of 1-methylnaphthalene to tetrahydronaphthalene is 2.4-2.8:5.

Preferably, the biomass-low rank coal is co-heat-melted to produce ashless coal, wherein the low rank coal is selected from the group consisting of lignite, long flame coal, non-stick coal or a combination thereof.

Preferably, the biomass-low rank coal is co-heat-melted to produce ashless coal, wherein the biomass is selected from the group consisting of rice straw, wheat straw, chaff, wood chips, or a combination thereof.

Compared with the prior art, the raw materials used in the present invention are low rank coal and biomass, which expands the range of raw materials used for preparing ashless coal, can effectively reduce the cost of raw materials, and has the industrial prospect of realizing large quantities of ashless coal.

Detailed ways

The invention is further illustrated by the following examples of laboratory preparation of ashless coal by biomass-low rank coal co-heat dissolution, but does not limit the invention accordingly.

Example 1

1. Weigh 10g (dry basis) Thai lignite coal sample and 10g (dry basis) wood chip sample and mix it evenly. It is co-heat-dissolved in a batch reactor at 350 °C. The solvent is 1-methylnaphthalene. The amount was 300 ml, and the mixture was extracted by hot-melting for 1 hour under stirring, and the extract solution and the hot-soluble residue were separated by hot filtration.

2. The cooled extraction solution was separated by distillation under reduced pressure to remove the solvent to obtain 4.2 g of ashless coal, and the yield of dry ashless base was 35%.

3. Industrial analysis showed that the ash content of the obtained ashless coal was 0.08%, and the elemental analysis showed that the carbon content was 80%.

Example 2

1. Weigh 10g (dry basis) Thai lignite coal sample and 10g (dry basis) rice straw sample separately, and use the batch reactor to perform coheat solution treatment at 350 °C. The solvent is tetrahydronaphthalene and added. The amount was 300 ml, and it was extracted by hot-melting for 1 hour under stirring.

2. The cooled extraction solution was separated by distillation under reduced pressure to remove the solvent to obtain 2.52 g of ashless coal, and the yield of dry ashless base was 21%.

3. Industrial analysis showed that the ash content of the obtained ashless coal was 0.4%, and the elemental analysis showed a carbon content of 79%.

Example 3

1. Weigh 10g (dry basis) Australian lignite coal sample and 10g (dry basis) wood chip sample and mix it evenly. Mix it in a batch reactor at 350 °C, and use 1-methylnaphthalene in solvent. The amount was 300 ml, and the mixture was extracted by hot-melting for 1 hour under stirring, and the extract solution and the hot-soluble residue were separated by hot filtration.

2. The cooled extraction solution was separated by distillation under reduced pressure to remove the solvent to obtain 5.1 g of ashless coal, and the yield of dry ashless base was 32%.

3. Industrial analysis showed that the ash content of the obtained ashless coal was 0.15%, and the elemental analysis showed that the carbon content was 81%.

Example 4

1. Weigh 10g (dry basis) Australian lignite coal sample and 10g (dry basis) rice straw sample separately, and use the batch reactor to co-heat-dissolve at 350 °C. The solvent is 1-methylnaphthalene. The amount of the solution was 300 ml, and the mixture was extracted by hot-melting for 1 hour under stirring, and the extract solution and the hot-melt residue were separated by hot filtration.

2. The cooled extraction solution was separated by distillation under reduced pressure to remove the solvent, and 6 g of ashless coal was obtained by extraction, and the yield of dry ashless base was 35%.

3. Industrial analysis showed that the ash content of the obtained ashless coal was 0.05%, and the elemental analysis showed that the carbon content was 83%.

Example 5

1. Weigh 10g (dry basis) Australian lignite coal sample and 10g (dry basis) rice straw sample separately, and use the batch reactor to co-heat-dissolve at 350 °C. The solvent is 1-methylnaphthalene. In combination with tetrahydronaphthalene, the mass ratio of 1-methylnaphthalene to tetrahydronaphthalene is 1.2:5, the total amount of solvent added is 300 ml, and the mixture is extracted by hot-dissolving for 1 hour under stirring, and the extraction solution is separated by hot filtration. And hot residue.

2. The cooled extraction solution was separated by distillation under reduced pressure to remove the solvent, and 6.2 g of ashless coal was obtained by extraction, and the yield of dry ashless base was 36%.

3. Industrial analysis showed that the ash content of the obtained ashless coal was 0.04%, and elemental analysis showed that the carbon content was 85%.

Example 6

1. Weigh 10g (dry basis) Australian lignite coal sample and 10g (dry basis) rice straw sample separately, and use the batch reactor to co-heat-dissolve at 350 °C. The solvent is 1-methylnaphthalene. In combination with tetrahydronaphthalene, the mass ratio of 1-methylnaphthalene to tetrahydronaphthalene is 3.3:5, the total amount of solvent added is 300 ml, and the mixture is extracted by hot-dissolving for 1 hour under stirring, and the extraction solution is separated by hot filtration. And hot residue.

2. The cooled extraction solution was separated by distillation under reduced pressure to remove the solvent, and 6.1 g of ashless coal was obtained by extraction, and the yield of dry ashless base was 36%.

3. Industrial analysis showed that the ash content of the obtained ashless coal was 0.05%, and the elemental analysis showed a carbon content of 84%.

Example 7

1. Weigh 10g (dry basis) Australian lignite coal sample and 10g (dry basis) rice straw sample separately. Uniformly, co-heat-dissolving treatment was carried out in a batch reactor at 350 ° C. The solvent was a combination of 1-methylnaphthalene and tetrahydronaphthalene, and the mass ratio of 1-methylnaphthalene to tetrahydronaphthalene was 2.4:5. The solvent was added in a total amount of 300 ml, and the mixture was extracted by hot-melting for 1 hour under stirring, and the extract solution and the hot-soluble residue were separated by hot filtration.

2. The cooled extraction solution was separated by distillation under reduced pressure to remove the solvent, and 6.2 g of ashless coal was obtained by extraction, and the yield of dry ashless base was 37%.

3. Industrial analysis showed that the ash content of the obtained ashless coal was 0.03%, and the elemental analysis showed that the carbon content was 86%.

Example 8

1. Weigh 10g (dry basis) Australian lignite coal sample and 10g (dry basis) rice straw sample separately, and use the batch reactor to co-heat-dissolve at 350 °C. The solvent is 1-methylnaphthalene. In combination with tetrahydronaphthalene, the mass ratio of 1-methylnaphthalene to tetrahydronaphthalene is 2.8:5, the total amount of solvent added is 300 ml, and the mixture is extracted by hot-dissolving for 1 hour under stirring, and the extraction solution is separated by hot filtration. And hot residue.

2. The cooled extraction solution was separated by distillation under reduced pressure to remove the solvent, and 6.25 g of ashless coal was obtained by extraction, and the yield of dry ashless base was 37%.

3. Industrial analysis showed that the ash content of the obtained ashless coal was 0.03%, and the elemental analysis showed a carbon content of 87%.

The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments are obvious to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but the scope of the invention is to be accorded

Claims

A method for preparing ashless coal by biomass-low-rank coal co-heat-dissolving, characterized in that it comprises the following steps:

1) using biomass and low rank coal as raw materials, mixing and then using aromatic hydrocarbons as solvent for hot solution;

2) After hot-dissolving, the extract is obtained by hot extraction, and after cooling, the solvent in the extract is separated to obtain ash-free coal.
The biomass-low rank coal co-thermally soluble ashless coal process according to claim 1, wherein the aromatic hydrocarbon is selected from the group consisting of 1-methylnaphthalene, tetrahydronaphthalene or a combination thereof.
The method for preparing ashless coal by biomass-low-rank coal co-heat-dissolving according to claim 1, wherein the temperature during the hot extraction is controlled at 250-350 °C.
The method for preparing ashless coal by biomass-low-rank coal co-heat-dissolving according to claim 1, wherein the extraction time is controlled to be 0.5-1 hour.
The method for preparing ashless coal by biomass-low rank coal co-heat-dissolving according to claim 2, wherein the aromatic hydrocarbon comprises 1-methylnaphthalene and tetrahydronaphthalene, 1-methylnaphthalene and tetrahydrogen. The mass ratio of naphthalene is from 1.2 to 3.3:5.
The method for preparing ashless coal by biomass-low-rank coal co-heat-dissolving according to claim 5, wherein the mass ratio of 1-methylnaphthalene to tetrahydronaphthalene is 2.4-2.8:5.
The biomass-low rank coal co-heat-melting process for preparing ashless coal according to claim 1, wherein the low rank coal is selected from the group consisting of lignite, long flame coal, non-stick coal or a combination thereof.
The biomass-low rank coal co-heat-melting process for preparing ashless coal according to claim 1, wherein the biomass is selected from the group consisting of rice straw, wheat straw, chaff, wood chips or a combination thereof.