Method and apparatus for producing natural gas through combination of smashed coal pressurized gasification and dry-process entrained-bed gasification

Abstract

The invention provides a method and apparatus for producing natural gas through combination of smashed coal pressurized gasification and dry-process entrained-bed gasification. Smashed coal pressurized gasification and dry-process entrained-bed gasification technologies are organically combined, low-heat raw gas generated by a smashed-coal gasification furnace is utilized to chill a high-heat coal gas generated by a dry-process entrained-bed gasification furnace, tar, phenols and other substances in raw gas are gasified and are converted into raw-gas compositions. The wastewater processing problem of the smashed-coal pressurized gasification technology is essentially solved, also disposition of residual pulverized coal in the smashed-coal pressurized gasification technology is solved. Under the premise of not increasing the investment, the coal-made natural gas output is improved, wastewater investment and running cost are reduced, and the method is an optimized technological route for coal-made natural gas.

Description

technical field

[0001] The invention belongs to the technical field of coal-to-natural gas. Specifically, the present invention relates to a method and device for producing natural gas by pressurized gasification of crushed coal combined with dry-process entrained gasification. Background technique

[0002] The characteristics of China's resources are "rich in coal, short of oil and low in gas". The three major economic belts around the Bohai Sea, the Yangtze River Delta and the Pearl River Delta have a huge demand for natural gas, while Inner Mongolia and Xinjiang are rich in coal resources, but the transportation costs are high. Therefore, the in-situ conversion of coal resources in coal-rich areas into natural gas has become another important strategic choice after coal power generation, coal-to-oil, and coal-to-olefins.

[0003] Coal gasification plays an important role in the coal-to-natural gas process route. The essence of gasification is the reaction of coal and g...

Examples

Embodiment 1

[0057] see figure 1 As shown in the flow chart, this embodiment describes a specific implementation of the method and device for producing natural gas by pressurized gasification of crushed coal combined with dry entrained gasification of the present invention.

[0058] The specific operation is as follows:

[0059] In this example, the pressure gasification of crushed coal adopts a gasification agent composed of lignite with a particle size of 13-50 mm, water vapor and pure oxygen, and is carried out in countercurrent contact in a pressure gasifier of crushed coal under a pressure of 3.0 to 4.1 MPa. Gasification reaction, the temperature of the coal gas exiting the gasifier is about 225-600°C, and the main components of the reaction product are CO, H 2 , CO 2 、CH 4 and undecomposed water vapor with a small amount of C n h m , N 2 , sulfide (mostly H 2 S), tar, naphtha, phenol, fatty acid, ammonia, naphthalene and other mixtures.

[0060] Specifically, the crushed coal...

Embodiment 2

[0067] By the process method described in the above embodiment 1, with daily output 400 * 10 4 N m 3 The calculation of the natural gas project, the economic benefits are as follows:

[0068] (1) Investment cost:

[0069] In the first phase of the project, the investment in 4 sets of gas-water separation and 2 sets of phenol recovery projects (including equipment purchase, installation engineering and construction engineering) is 336 million yuan.

[0070] (2) Annual production benefit:

[0071]1. The operating cost of wastewater pretreatment is about 30 yuan / t waste water×30t / furnace×8000 hours=7.2 million yuan;

[0072] 2. According to the oil produced mainly by the pressurized gasification and carbonization of crushed coal, all of them are converted into gas, and the calculated gas yield is 1.09NM 3 / kg, while the original design gas yield is 0.965NM 3 / kg;

[0073] (1.09-0.965)×40287kg×8000 hours=40.29 million NM 3 ÷3.738=10.78 million NM 3 × 2.7 yuan = 29.11 milli...

technical field

[0001] The invention belongs to the technical field of coal-to-natural gas. Specifically, the present invention relates to a method and device for producing natural gas by pressurized gasification of crushed coal combined with dry-process entrained gasification. Background technique

[0002] The characteristics of China's resources are "rich in coal, short of oil and low in gas". The three major economic belts around the Bohai Sea, the Yangtze River Delta and the Pearl River Delta have a huge demand for natural gas, while Inner Mongolia and Xinjiang are rich in coal resources, but the transportation costs are high. Therefore, the in-situ conversion of coal resources in coal-rich areas into natural gas has become another important strategic choice after coal power generation, coal-to-oil, and coal-to-olefins.

[0003] Coal gasification plays an important role in the coal-to-natural gas process route. The essence of gasification is the reaction of coal and g...

Examples

Embodiment 1

[0057] see figure 1 As shown in the flow chart, this embodiment describes a specific implementation of the method and device for producing natural gas by pressurized gasification of crushed coal combined with dry entrained gasification of the present invention.

[0058] The specific operation is as follows:

[0059] In this example, the pressure gasification of crushed coal adopts a gasification agent composed of lignite with a particle size of 13-50 mm, water vapor and pure oxygen, and is carried out in countercurrent contact in a pressure gasifier of crushed coal under a pressure of 3.0 to 4.1 MPa. Gasification reaction, the temperature of the coal gas exiting the gasifier is about 225-600°C, and the main components of the reaction product are CO, H 2 , CO 2 、CH 4 and undecomposed water vapor with a small amount of C n h m , N 2 , sulfide (mostly H 2 S), tar, naphtha, phenol, fatty acid, ammonia, naphthalene and other mixtures.

[0060] Specifically, the crushed coal...

Embodiment 2

[0067] By the process method described in the above embodiment 1, with daily output 400 * 10 4 N m 3 The calculation of the natural gas project, the economic benefits are as follows:

[0068] (1) Investment cost:

[0069] In the first phase of the project, the investment in 4 sets of gas-water separation and 2 sets of phenol recovery projects (including equipment purchase, installation engineering and construction engineering) is 336 million yuan.

[0070] (2) Annual production benefit:

[0071]1. The operating cost of wastewater pretreatment is about 30 yuan / t waste water×30t / furnace×8000 hours=7.2 million yuan;

[0072] 2. According to the oil produced mainly by the pressurized gasification and carbonization of crushed coal, all of them are converted into gas, and the calculated gas yield is 1.09NM 3 / kg, while the original design gas yield is 0.965NM 3 / kg;

[0073] (1.09-0.965)×40287kg×8000 hours=40.29 million NM 3 ÷3.738=10.78 million NM 3 × 2.7 yuan = 29.11 milli...

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