阅读说明：本技术 一种低碳技术合成甲醇的方法 (Method for synthesizing methanol by low-carbon technology ) 是由 贾开程 赵煜 王秋银 普微 于 2020-06-12 设计创作，主要内容包括：本发明公开了一种低碳技术合成甲醇的方法,包括以下步骤：步骤一：水煤浆制备；步骤二：煤气化；步骤三：CO变换、低温甲醇洗；步骤四：甲烷蒸汽转化；步骤五：合成压缩机；步骤六：甲醇合成、MTO甲醇制备；步骤七：灰水处理；步骤八：重金属处理,所述灰水处理中污水存在重金属镍,所述重金属处理投入的硫化物和重金属镍反应,所述重金属处理反应后产生沉淀和混合水,且混合水与水煤浆制备水混合,所述水煤浆制备混合水与煤混合。本发明有益效果是：利用重金属处理进行污水处理,重金属处理过程投入硫化物,采用硫化物沉淀法进行重金属镍的沉淀,过量的硫化物混合水与水煤浆混合,与原料煤中重金属反应,减少水煤浆中重金属含量。(The invention discloses a method for synthesizing methanol by a low-carbon technology, which comprises the following steps: the method comprises the following steps: preparing coal water slurry; step two: coal gasification; step three: CO conversion and low-temperature methanol washing; step four: carrying out methane steam conversion; step five: synthesizing a compressor; step six: methanol synthesis and MTO methanol preparation; step seven: treating grey water; step eight: heavy metal treatment, wherein heavy metal nickel exists in sewage in the grey water treatment, sulfide added in the heavy metal treatment reacts with the heavy metal nickel, precipitate and mixed water are generated after the heavy metal treatment reaction, the mixed water is mixed with water for preparing coal water slurry, and the mixed water for preparing the coal water slurry is mixed with coal. The invention has the beneficial effects that: and (2) carrying out sewage treatment by utilizing heavy metal treatment, adding sulfide in the heavy metal treatment process, precipitating heavy metal nickel by adopting a sulfide precipitation method, mixing excessive sulfide mixed water with the coal water slurry, and reacting with heavy metal in the raw material coal to reduce the content of heavy metal in the coal water slurry.)

1. A method for synthesizing methanol by a low-carbon technology is characterized by comprising the following steps:

the method comprises the following steps: preparing coal water slurry, mixing raw material coal and water, continuously stirring and mixing to prepare the coal water slurry, mixing and precipitating the water and the raw material coal to generate coarse slag in the mixing process of the coal water slurry, separating the coarse slag from the coal water slurry, and discharging the coal water slurry to enter coal gasification equipment;

step two: coal gasification, namely introducing oxygen into the coal water slurry and the air separation device to perform coal gasification reaction to generate raw coal gas;

step three: CO transformation and low-temperature methanol washing, wherein the crude gas is subjected to CO transformation, and the low-temperature methanol washing is used for desulfurizing and decarbonizing the changed gas;

step four: performing methane steam conversion, namely performing methane steam conversion on raw natural gas and combustion natural gas to generate synthesis gas;

step five: a synthesis compressor, wherein the synthesis gas obtained by converting the coal synthesis gas and the methane steam enters the synthesis compressor, and the compressed gas enters the methanol synthesis equipment;

step six: methanol synthesis and MTO methanol preparation, wherein the compressed gas is used for preparing and synthesizing MTO methanol through methanol synthesis equipment and MTO methanol;

step seven: treating the grey water to generate fine slag and sewage, and introducing the sewage into heavy metal treatment equipment;

step eight: and (3) heavy metal treatment, namely adding sulfide into heavy metal treatment equipment, reacting the sulfide with sewage in the heavy metal treatment equipment, reacting the heavy metal with the sulfide to generate precipitate, and mixing the upper-layer sewage with water and coal to prepare the coal water slurry.

2. The method for synthesizing methanol by using a low-carbon technology as claimed in claim 1, wherein heavy metal nickel exists in the sewage in the grey water treatment.

3. The method for synthesizing methanol by using a low carbon technology as claimed in claim 2, wherein the sulfide added in the heavy metal treatment reacts with heavy metal nickel, the heavy metal treatment reaction produces precipitate and mixed water, and the mixed water is mixed with the water prepared from the coal water slurry.

4. The method for synthesizing methanol by using a low carbon technology as claimed in claim 3, wherein the mixed water prepared from the coal water slurry is mixed with coal, the mixed water prepared from the coal water slurry contains sulfides, the sulfides react with the raw coal in the coal water slurry, and the coarse slag generated in the preparation process of the coal water slurry contains heavy metal nickel.

Technical Field

The invention relates to the field of methanol synthesis methods, in particular to a method for synthesizing methanol by a low-carbon technology.

Background

Methanol is a saturated monohydric alcohol with the simplest structure, CAS number 67-56-1 or 170082-17-4, molecular weight 32.04, boiling point 64.7 ℃. It is also called "xylitol" or "wood essence" because it is found in dry-distilled wood for the first time. The lowest dose of poisoning in oral administration of people is about 100mg/kg of body weight, and 0.3-1 g/kg of poisoning in oral administration can kill the human body. Used for producing formaldehyde, agricultural chemicals, etc., and used as an extractant for organic substances and a denaturant for alcohol, etc. The finished product is usually prepared by the reaction of carbon monoxide and hydrogen, the methanol is prepared by adopting natural gas or petroleum gas, a mature process is provided, because the methanol prepared by the natural gas or petroleum gas can generate a large amount of excessive hydrogen, the conversion efficiency can be influenced on one hand, and on the other hand, the methanol prepared by taking the natural gas or petroleum gas as the raw material is difficult to control the cost because of the influence of the international price of the natural gas or petroleum; in the process of synthesizing methanol by adopting a low-carbon technology, heavy metal substances are contained in grey water treatment, so that the direct discharge of sewage is not beneficial to environmental protection, and when the sewage is adopted for preparing the coal water slurry, the heavy metal content in the coal water slurry is too high, so that the subsequent reaction is not beneficial.

Disclosure of Invention

The invention mainly aims to provide a method for synthesizing methanol by a low-carbon technology, which can effectively solve the problems in the background technology.

In order to achieve the purpose, the invention adopts the technical scheme that:

a method for synthesizing methanol by a low-carbon technology comprises the following steps:

the method comprises the following steps: preparing coal water slurry, mixing raw material coal and water, continuously stirring and mixing to prepare the coal water slurry, mixing and precipitating the water and the raw material coal to generate coarse slag in the mixing process of the coal water slurry, separating the coarse slag from the coal water slurry, and discharging the coal water slurry to enter coal gasification equipment;

step two: coal gasification, namely introducing oxygen into the coal water slurry and the air separation device to perform coal gasification reaction to generate raw coal gas;

step three: CO transformation and low-temperature methanol washing, wherein the crude gas is subjected to CO transformation, and the low-temperature methanol washing is used for desulfurizing and decarbonizing the changed gas;

step four: performing methane steam conversion, namely performing methane steam conversion on raw natural gas and combustion natural gas to generate synthesis gas;

step five: a synthesis compressor, wherein the synthesis gas obtained by converting the coal synthesis gas and the methane steam enters the synthesis compressor, and the compressed gas enters the methanol synthesis equipment;

step six: methanol synthesis and MTO methanol preparation, wherein the compressed gas is used for preparing and synthesizing MTO methanol through methanol synthesis equipment and MTO methanol;

step seven: treating the grey water to generate fine slag and sewage, and introducing the sewage into heavy metal treatment equipment;

step eight: and (3) heavy metal treatment, namely adding sulfide into heavy metal treatment equipment, reacting the sulfide with sewage in the heavy metal treatment equipment, reacting the heavy metal with the sulfide to generate precipitate, and mixing the upper-layer sewage with water and coal to prepare the coal water slurry.

Preferably, the heavy metal nickel is present in the grey water treatment effluent.

Preferably, the sulfide added in the heavy metal treatment reacts with heavy metal nickel, precipitate and mixed water are generated after the heavy metal treatment reaction, and the mixed water is mixed with the water for preparing the coal water slurry.

Preferably, the mixed water for preparing the coal water slurry is mixed with coal, the mixed water for preparing the coal water slurry contains sulfides, the sulfides react with the raw coal in the coal water slurry, and coarse slag generated in the preparation process of the coal water slurry contains heavy metal nickel.

Compared with the prior art, the invention has the following beneficial effects: and (2) carrying out sewage treatment by utilizing heavy metal treatment, adding sulfide in the heavy metal treatment process, precipitating heavy metal nickel by adopting a sulfide precipitation method, mixing excessive sulfide mixed water with the coal water slurry, and reacting with heavy metal in the raw material coal to reduce the content of heavy metal in the coal water slurry.

Drawings

FIG. 1 is a schematic diagram of a method for synthesizing methanol by a low-carbon technology of the invention.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.