Method for producing low-carbon alcohol and co-producing natural gas and urea with syngas and coke oven gas

Abstract

A method for syngas and coke oven gas to produce low-carbon alcohol and co-produce natural gas and urea is to mix crude synthesis gas and coke oven gas to form a raw material gas that satisfies the hydrogen-carbon ratio of low-carbon alcohol synthesis; the raw material gas is washed with methanol at low temperature, The released hydrogen sulfide is desulfurized and recovered, and the removed carbon dioxide is purified by CO2 stripping; the raw material gas washed with low-temperature methanol is subjected to methane separation, and the released methane is made into LNG or CNG, and the pure gas after methane separation is used for synthesis of low-carbon Alcohol reaction, the gas obtained as purge gas enters the PSA for separation, the separated gas mainly includes CO, CO2 and CH4, etc., and returns to the low-temperature methanol washing cycle, and the separated H2 and N2 obtained by air separation are reacted to synthesize ammonia to obtain synthetic ammonia; after purification CO2 reacts with synthetic ammonia to synthesize urea to produce urea products; the obtained liquid phase products are separated from low-carbon alcohols to obtain low-carbon alcohol products. The invention has the advantage of improving the utilization rate of raw gas.

Description

technical field

[0001] The invention belongs to a method for synthesizing low-carbon alcohol, in particular to a method for producing low-carbon alcohol from synthesis gas and coke oven gas and co-producing natural gas and urea. Background technique

[0002] Low carbon alcohol usually refers to the mixture of C1~C5 alcohols. The application prospect is very wide: low-carbon alcohol can be used as an alternative fuel, although its calorific value is low, it is fully combusted and emits less CO, NOx, hydrocarbons, etc. during combustion, which is an environmentally friendly fuel; low-carbon alcohol It can also be used as a fuel additive. The currently used gasoline additive methyl tert-butyl ether will eventually be banned with the advancement of technology due to problems such as storage and transportation, which provides an opportunity for the development of low-carbon alcohols. Moreover, the low-carbon alcohol has a high octane number, and has good explosion-proof and sho...

Examples

Embodiment 1

[0039] Feed raw coal, water vapor and oxygen from the air separation unit into the gasifier to obtain crude synthesis gas, then pass the crude synthesis gas and coke oven gas into the gas cabinet to fully mix to form a hydrogen-carbon molar ratio that satisfies the low-carbon alcohol synthesis. 2 Raw material gas with / CO=3.6.

[0040] The raw material gas is compressed to 3.5MPa and enters the low-temperature methanol washing and purification device to remove impurities such as hydrogen sulfide and carbon dioxide. 2 S off to less than 0.1ppm, CO 2 Less than 20ppm, the hydrogen sulfide H removed 2 S desulfurization recovery, the removed carbon dioxide through CO 2 Purification by steam stripping.

[0041] The raw material gas washed and purified by low-temperature methanol enters the methane separation, and the methane in the crude gas is separated to obtain LNG at a temperature of -162°C and a pressure of 3.5Mpa by using the cryogenic separation technology of American Chem...

Embodiment 2

[0046] Feed raw coal, water vapor and oxygen from the air separation unit into the gasifier to obtain crude synthesis gas, then pass the crude synthesis gas and coke oven gas into the gas cabinet to fully mix to form a hydrogen-carbon molar ratio that satisfies the low-carbon alcohol synthesis. 2 Raw material gas with / CO=2.9.

[0047] The raw material gas is compressed to 5.0MPa and enters the low-temperature methanol washing and purification device to remove impurities such as hydrogen sulfide and carbon dioxide. 2 S off to less than 0.1ppm, CO 2 Less than 20ppm, the hydrogen sulfide H removed 2 S desulfurization recovery, the removed carbon dioxide through CO 2 Purification by steam stripping.

[0048] The raw material gas washed and purified by low-temperature methanol enters the methane separation, and the methane in the crude gas is separated to obtain LNG at a temperature of -165°C and a pressure of 5.0Mpa by using the cryogenic separation technology of American Chem...

Embodiment 3

[0053] Feed raw coal, water vapor and oxygen from the air separation unit into the gasifier to obtain crude synthesis gas, then pass the crude synthesis gas and coke oven gas into the gas cabinet to fully mix to form a hydrogen-carbon molar ratio that satisfies the low-carbon alcohol synthesis. 2 Raw material gas with / CO=4.1.

[0054] The raw material gas is compressed to 4.5MPa and enters the low-temperature methanol washing and purification device to remove impurities such as hydrogen sulfide and carbon dioxide. 2 S off to less than 0.1ppm, CO 2 Less than 20ppm, the hydrogen sulfide H removed 2 S desulfurization recovery, the removed carbon dioxide through CO 2 Purification by steam stripping.

[0055] The raw material gas washed and purified by low-temperature methanol enters methane separation, and the methane in the gas is separated by supercritical gas extraction and separation technology at a pressure of 4.5MPa and a temperature of -77°C to obtain CNG (compressed na...

technical field

[0001] The invention belongs to a method for synthesizing low-carbon alcohol, in particular to a method for producing low-carbon alcohol from synthesis gas and coke oven gas and co-producing natural gas and urea. Background technique

[0002] Low carbon alcohol usually refers to the mixture of C1~C5 alcohols. The application prospect is very wide: low-carbon alcohol can be used as an alternative fuel, although its calorific value is low, it is fully combusted and emits less CO, NOx, hydrocarbons, etc. during combustion, which is an environmentally friendly fuel; low-carbon alcohol It can also be used as a fuel additive. The currently used gasoline additive methyl tert-butyl ether will eventually be banned with the advancement of technology due to problems such as storage and transportation, which provides an opportunity for the development of low-carbon alcohols. Moreover, the low-carbon alcohol has a high octane number, and has good explosion-proof and sho...

Examples

Embodiment 1

[0039] Feed raw coal, water vapor and oxygen from the air separation unit into the gasifier to obtain crude synthesis gas, then pass the crude synthesis gas and coke oven gas into the gas cabinet to fully mix to form a hydrogen-carbon molar ratio that satisfies the low-carbon alcohol synthesis. 2 Raw material gas with / CO=3.6.

[0040] The raw material gas is compressed to 3.5MPa and enters the low-temperature methanol washing and purification device to remove impurities such as hydrogen sulfide and carbon dioxide. 2 S off to less than 0.1ppm, CO 2 Less than 20ppm, the hydrogen sulfide H removed 2 S desulfurization recovery, the removed carbon dioxide through CO 2 Purification by steam stripping.

[0041] The raw material gas washed and purified by low-temperature methanol enters the methane separation, and the methane in the crude gas is separated to obtain LNG at a temperature of -162°C and a pressure of 3.5Mpa by using the cryogenic separation technology of American Chem...

Embodiment 2

[0046] Feed raw coal, water vapor and oxygen from the air separation unit into the gasifier to obtain crude synthesis gas, then pass the crude synthesis gas and coke oven gas into the gas cabinet to fully mix to form a hydrogen-carbon molar ratio that satisfies the low-carbon alcohol synthesis. 2 Raw material gas with / CO=2.9.

[0047] The raw material gas is compressed to 5.0MPa and enters the low-temperature methanol washing and purification device to remove impurities such as hydrogen sulfide and carbon dioxide. 2 S off to less than 0.1ppm, CO 2 Less than 20ppm, the hydrogen sulfide H removed 2 S desulfurization recovery, the removed carbon dioxide through CO 2 Purification by steam stripping.

[0048] The raw material gas washed and purified by low-temperature methanol enters the methane separation, and the methane in the crude gas is separated to obtain LNG at a temperature of -165°C and a pressure of 5.0Mpa by using the cryogenic separation technology of American Chem...

Embodiment 3

[0053] Feed raw coal, water vapor and oxygen from the air separation unit into the gasifier to obtain crude synthesis gas, then pass the crude synthesis gas and coke oven gas into the gas cabinet to fully mix to form a hydrogen-carbon molar ratio that satisfies the low-carbon alcohol synthesis. 2 Raw material gas with / CO=4.1.

[0054] The raw material gas is compressed to 4.5MPa and enters the low-temperature methanol washing and purification device to remove impurities such as hydrogen sulfide and carbon dioxide. 2 S off to less than 0.1ppm, CO 2 Less than 20ppm, the hydrogen sulfide H removed 2 S desulfurization recovery, the removed carbon dioxide through CO 2 Purification by steam stripping.

[0055] The raw material gas washed and purified by low-temperature methanol enters methane separation, and the methane in the gas is separated by supercritical gas extraction and separation technology at a pressure of 4.5MPa and a temperature of -77°C to obtain CNG (compressed na...

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