System and method for recycling CO product vent gas
阅读说明：本技术 一种回收co产品放空气系统及方法 (System and method for recycling CO product vent gas ) 是由 张卫波 田海明 聂家波 赵英桥 张志峰 王学昆 于 2019-10-24 设计创作，主要内容包括：本发明涉及一种回收CO产品放空气系统及方法,在压缩机出口增加两路管线,一路为回收气精配管线,管径为D1,另一路为回收气粗配管线,管径为D2,其中D1<D2。两路管线并入丁辛醇总管中,在丁辛醇总管上安装CO在线分析仪AI1。精配管线上安装精配调节阀PV3和精配压力变送器PIC3,以及精配流量计FI1,精配调节阀PV3通过精配压力变送器PIC3自动保压Y。粗配管线上安装粗配调节阀PV4和粗配压力变送器PIC4,以及粗配流量计FI2,粗配调节阀PV4通过粗配压力变送器PIC4自动保压Z。解决了回收200-8000Nm3/h流量波动大问题,流量计和CO分析仪根据流量大小调整精合成气总管的CO含量。(The invention relates to a system and a method for recycling CO product vent gas, wherein two pipelines are added at the outlet of a compressor, one pipeline is a recycled gas fine distribution pipeline, the pipe diameter is D1, the other pipeline is a recycled gas rough distribution pipeline, and the pipe diameter is D2, wherein D1 is less than D2. The two pipelines are merged into a butanol-octanol main pipe, and a CO on-line analyzer AI1 is installed on the butanol-octanol main pipe. And a precise distribution regulating valve PV3, a precise distribution pressure transmitter PIC3 and a precise distribution flow meter FI1 are arranged on the precise distribution pipeline, and the precise distribution regulating valve PV3 automatically maintains pressure Y through the precise distribution pressure transmitter PIC 3. The rough distribution pipeline is provided with a rough distribution regulating valve PV4, a rough distribution pressure transmitter PIC4 and a rough distribution flowmeter FI2, and the rough distribution regulating valve PV4 automatically maintains pressure Z through the rough distribution pressure transmitter PIC 4. The problem of large flow fluctuation of 200-8000Nm3/h in recovery is solved, and the flow meter and the CO analyzer adjust the CO content of the fine synthesis gas main pipe according to the flow.)
1. A system for recycling CO products and exhausting gas is characterized in that two pipelines are additionally arranged at the outlet of a compressor, wherein one pipeline is a recycled gas fine distribution pipeline (4) with the pipe diameter of D1, the other pipeline is a recycled gas coarse distribution pipeline (5) with the pipe diameter of D2, and D1 is less than D2.
2. A venting system as claimed in claim 1, characterized in that the two-way line merges into the butanol-octanol mains (6), on which (6) the CO on-line analyzer AI1 is mounted.
3. The air vent system of claim 1, wherein a fine adjustment valve PV3 and a fine adjustment pressure transmitter PIC3 are installed on the fine adjustment pipeline, and a fine adjustment flow meter FI1, and the fine adjustment valve PV3 automatically maintains pressure Y through the fine adjustment pressure transmitter PIC 3.
4. The air vent system of claim 1, wherein a rough distribution regulating valve PV4 and a rough distribution pressure transducer PIC4 are installed on the rough distribution pipeline, and a rough distribution flowmeter FI2, and the rough distribution regulating valve PV4 automatically maintains the pressure Z by the rough distribution pressure transducer PIC 4.
5. The air vent system of claim 3 or 4, wherein the pipeline is flanged to the control valve, the pressure transmitter and the pipeline are led out through a pressure leading pipe and then enter the instrument box to be connected to the pressure transmitter, the flow meter is an orifice plate flow meter, and the flow rate is calculated by measuring the pressure difference between the front and the back of the orifice plate.
6. The method for recovering vent gas of CO products by using the system of claim 1 is characterized in that in normal production, according to the process requirements, a gas supply regulating valve PV1 automatically maintains pressure W through a gas supply pressure transmitter PIC1, a vent valve PV2 automatically maintains pressure X through a vent pressure transmitter PIC2, a fine adjustment regulating valve PV3 automatically maintains pressure Y through the pressure of a fine adjustment pressure transmitter PIC3, and a coarse adjustment regulating valve PV4 automatically maintains pressure Z through the pressure of a coarse adjustment pressure transmitter PIC4, wherein W < Y < Z < X.
7. The method of claim 6, wherein each of W < Y < Z < X differs by 0.05 MPa.
8. The method as claimed in claim 6, characterized in that when the compressor pressure is between W-Y, the emptying valve PV2 fine adjustment valve PV3 coarse adjustment valve PV4 is closed, when the pressure exceeds Y, the fine adjustment valve PV3 is opened, the pressure is adjusted by PIC3 to stabilize, if the compressor pressure fluctuates greatly and the pressure exceeds Z, the coarse adjustment valve PV4 is opened, the pressure is adjusted by the fine adjustment pressure transmitter PIC3 and the coarse adjustment pressure transmitter PIC4 to stabilize simultaneously, if the pressure exceeds X, the emptying valve PV2 is opened, and the compressor pressure is adjusted to stabilize by emptying the pressure transmitter PIC 2.
9. The method as set forth in claim 6, characterized in that the amount of the air released is 6000-.
10. The process as claimed in claim 9, characterized in that the fine adjustment valve PV3 is closed, the coarse adjustment valve PV4 is automatically pressure-maintained by the pressure of a coarse adjustment pressure transmitter PIC4 by Z, the feed air adjustment valve PV1 is automatically pressure-maintained by W by the feed air pressure transmitter PIC1, and the blow valve PV2 is automatically pressure-maintained by X by the blow air pressure transmitter PIC2, W < Z < X.
Technical Field
The invention belongs to the field of chemical production, relates to coal gas CO-production, and particularly relates to a system and a method for recycling CO product vent gas.
Background
A CO cold box belongs to a process of coal gas production, and is characterized in that purified unchanged gas washed by low-temperature methanol is sent into the cold box after methanol and CO2 are removed in an adsorption station, H2 and CO are separated, and the separated CO is compressed by a CO compressor and then sent to a downstream acetic acid device. The specific flow is shown in figure 1, the outlet of the compressor is divided into two pipelines, one pipeline is a compressor air supply pipeline, an air supply regulating valve PV1 and an air supply pressure transmitter PIC1 are installed on the air supply pipeline, the air supply pressure transmitter PIC1 automatically maintains pressure W, when the pressure is higher than W, the air supply regulating valve PV1 is gradually opened to 100%, and when the pressure is lower than W, the air supply regulating valve PV1 is gradually closed; and the other pipeline is a compressor vent pipeline, a vent valve PV2 and a vent pressure transmitter PIC2 are installed on the pipeline, the vent pressure transmitter PIC2 automatically maintains pressure X, and when the pressure exceeds X, the vent valve PV2 is gradually opened to ensure stable outlet pressure of the CO compressor.
Because the coal gas CO-production products are more, the fluctuation of each product production device influences each other, the air input of the CO cold box is unstable, and the outlet pressure of the CO compressor is unstable, so that the downstream pressure fluctuation is larger. The vent valve PV2 needs to ensure 1-2% vent opening degree to ensure the pressure stability of the downstream acetic acid device, but the CO product gas needs to be vented at 200 NM3/h every hour, and 400 million yuan is lost all the year round; and if the downstream acetic acid device needs 16-20 hours of temperature rise after stopping, the CO product gas can be increased step by step, and the CO cold box can only operate above 60% of the lowest load, in the period, 8000NM3/h of product gas is discharged, and the loss is also large. The difficulty of simultaneously recycling the two gases is very large, and the main problems are that: the two gas streams are recycled to ensure the stable pressure of the compressed outlet gas and not to influence the gas used by a downstream acetic acid device; on the other hand, the gas flow fluctuation is large due to the change of the recovered gas flow from 200-; what be exactly again the blow-down gas of retrieving goes to, through the screening, the route that can merge into this gas only is smart synthetic gas house steward, nevertheless merges behind the smart synthetic gas house steward, and the hydrogen carbon ratio of smart synthetic gas house steward adjusts the degree of difficulty greatly.
Disclosure of Invention
The invention aims to recover product gas discharged at normal times when a downstream acetic acid device is stopped.
The technical scheme of the invention is as follows:
a system for recycling CO products and exhausting gas is characterized in that two pipelines are additionally arranged at the outlet of a compressor, one pipeline is a recycled gas fine distribution pipeline 4 with the pipe diameter of D1, the other pipeline is a recycled gas coarse distribution pipeline 5 with the pipe diameter of D2, wherein D1 is less than D2.
The two pipelines are merged into a butanol-octanol
And the fine distribution pipeline is provided with a fine distribution regulating valve PV3, a fine distribution pressure transmitter PIC3 and a fine distribution flow meter FI1, and the fine distribution regulating valve PV3 automatically maintains pressure Y through the fine distribution
And a rough distribution adjusting valve PV4, a rough distribution pressure transmitter PIC4 and a rough distribution flowmeter FI2 are arranged on the rough distribution pipeline, and the rough distribution adjusting valve PV4 automatically maintains the pressure Z through the rough distribution pressure transmitter PIC 4.
The pipeline is connected with the regulating valve through a flange, the pressure transmitter and the pipeline are led out through the pressure leading pipe and then enter the instrument box to be connected with the pressure transmitter, the flowmeter is a pore plate flowmeter, and the flow is calculated through measuring the front-back pressure difference of the pore plate.
The invention relates to an operation method of a vent gas system for recovering CO products, which is characterized in that during normal production, according to process requirements, a gas supply regulating valve PV1 automatically maintains pressure W through a gas supply pressure transmitter PIC1, a vent valve PV2 automatically maintains pressure X through a vent pressure transmitter PIC2, a fine adjustment regulating valve PV3 automatically maintains pressure Y through the pressure of a fine adjustment pressure transmitter PIC3, and a coarse adjustment regulating valve PV4 automatically maintains pressure Z through the pressure of a coarse adjustment pressure transmitter PIC4, wherein W < Y < Z < X.
Preferably, each set of W < Y < Z < X differs by 0.05 MPa.
When the pressure of the compressor is between W and Y, the vent valve PV2 fine adjustment valve PV3 coarse adjustment valve PV4 is closed, when the pressure exceeds Y, the fine adjustment valve PV3 is opened, the pressure is adjusted to be stable through PIC3, if the pressure fluctuation of the compressor is large, the pressure exceeds Z, the coarse adjustment valve PV4 is opened, the pressure is adjusted to be stable through the fine adjustment pressure transmitter PIC3 and the coarse adjustment pressure transmitter PIC4, if the pressure exceeds X, the vent valve PV2 is opened, and the pressure of the compressor is adjusted to be stable through the vent
According to the vent gas system for recovering CO products, when a downstream acetic acid device stops or starts to heat, the vent amount is 6000-one
And closing the fine adjustment valve PV3, automatically maintaining the pressure Z of the coarse adjustment valve PV4 through the pressure of a coarse adjustment pressure transmitter PIC4, automatically maintaining the pressure W of the air supply adjustment valve PV1 through an air supply pressure transmitter PIC1, and automatically maintaining the pressure X of the emptying pressure transmitter PIC2 through an emptying valve PV2, wherein W < Z < X.
The concrete description is as follows:
two pipelines are added at the outlet of the compressor, one pipeline is a recovered gas fine distribution pipeline 4 with the pipe diameter of D1, the other pipeline is a recovered gas coarse distribution pipeline 5 with the pipe diameter of D2, wherein D1 is less than D2, the two pipelines are merged into a butanol-octanol
During normal production, according to the process requirements, the air supply regulating valve PV1 automatically maintains pressure W through the air supply pressure transmitter PIC1, the emptying valve PV2 automatically maintains pressure X through the emptying pressure transmitter PIC2, the fine adjustment regulating valve PV3 automatically maintains pressure Y through the pressure of the fine adjustment pressure transmitter PIC3, the coarse adjustment regulating valve PV4 automatically maintains pressure Z through the pressure of the coarse adjustment pressure transmitter PIC4, wherein W < Y < Z < X, and the phase difference of each set value is 0.05 MPa.
When the pressure of the compressor is between W and Y, the vent valve PV2 fine adjustment valve PV3 coarse adjustment valve PV4 is closed, when the pressure exceeds Y, the fine adjustment valve PV3 is opened, the pressure is adjusted to be stable through PIC3, if the pressure fluctuation of the compressor is large, the pressure exceeds Z, the coarse adjustment valve PV4 is opened, the pressure is adjusted to be stable through the fine adjustment pressure transmitter PIC3 and the coarse adjustment pressure transmitter PIC4, if the pressure exceeds X, the vent valve PV2 is opened, and the pressure of the compressor is adjusted to be stable through the vent
When the downstream acetic acid device is stopped or started for heating, the air release amount is about 6000-
The problem of large flow fluctuation of 200-8000Nm3/h can be solved by adding two regulating valves with different pipe diameters, and the CO content of the refined synthesis gas main pipe can be adjusted according to the flow by adding two flow meters and an online CO analyzer.
Drawings
FIG. 1: a system diagram of a prior art solution;
FIG. 2: system diagram of an embodiment of the invention.
Wherein: 1-CO compressor process, 2-compressor gas supply pipeline, 3-compressor vent pipeline, 4-recovered gas fine distribution pipeline, 5-recovered gas coarse distribution pipeline, 6-fine synthesis gas main pipe, PV 1-gas supply regulating valve, PIC 1-gas supply pressure transmitter, PV 2-vent valve, PIC 2-vent pressure transmitter, PV 3-fine distribution regulating valve, PIC 3-fine distribution pressure transmitter, FI 1-fine distribution flowmeter, PV 4-coarse distribution regulating valve, PIC 4-coarse distribution pressure transmitter, FI 2-coarse distribution flowmeter, AI1-CO online analyzer
Detailed Description
The original flow shown in fig. 1 is divided into two pipelines at the outlet of the
Because the coal gas CO-production products are more, the fluctuation of each product production device influences each other, the air input of the CO cold box is unstable, and the outlet pressure of the CO compressor is unstable, so that the downstream pressure fluctuation is larger. The vent valve PV2 needs to ensure 1-2% vent opening degree to ensure the pressure stability of the downstream acetic acid device, but the CO product gas needs to be vented at 200 NM3/h every hour, and 400 million yuan is lost all the year round; and if the downstream acetic acid device needs 16-20 hours of temperature rise after stopping, the CO product gas can be increased step by step, and the CO cold box can only operate above 60% of the lowest load, in the period, 8000NM3/h of product gas is discharged, and the loss is also large. The difficulty of simultaneously recycling the two gases is very large, and the main problems are that: the two gas streams are recycled to ensure the stable pressure of the compressed outlet gas and not to influence the gas used by a downstream acetic acid device; on the other hand, the gas flow fluctuation is large due to the change of the recovered gas flow from 200-; what be exactly again the blow-down gas of retrieving goes to, through the screening, the route that can merge into this gas only is smart synthetic gas house steward, nevertheless merges behind the smart synthetic gas house steward, and the hydrogen carbon ratio of smart synthetic gas house steward adjusts the degree of difficulty greatly.
Based on the existing problems, the following schemes are designed and developed: two pipelines are added at the outlet of the compressor, one pipeline is a recovered gas fine distribution pipeline 4 with the pipe diameter of D1, the other pipeline is a recovered gas coarse distribution pipeline 5 with the pipe diameter of D2, wherein D1 is less than D2, the two pipelines are merged into a butanol-octanol
During normal production, the air supply regulating valve PV1 automatically maintains the pressure for 3.0MPa through the air supply pressure transmitter PIC1, the emptying valve PV2 automatically maintains the pressure for 3.15MPa through the emptying pressure transmitter PIC2, the fine adjustment regulating valve PV3 automatically maintains the pressure for 3.05MPa through the pressure of the fine adjustment pressure transmitter PIC3, and the coarse adjustment regulating valve PV4 automatically maintains the pressure for 3.1MPa through the pressure of the coarse adjustment pressure transmitter PIC 4.
When the pressure of the compressor is between W and Y, the vent valve PV2 fine adjustment valve PV3 coarse adjustment valve PV4 is closed, when the pressure exceeds Y, the fine adjustment valve PV3 is opened, the pressure is adjusted to be stable through PIC3, if the pressure fluctuation of the compressor is large, the pressure exceeds Z, the coarse adjustment valve PV4 is opened, the pressure is adjusted to be stable through the fine adjustment pressure transmitter PIC3 and the coarse adjustment pressure transmitter PIC4, if the pressure exceeds X, the vent valve PV2 is opened, and the pressure of the compressor is adjusted to be stable through the vent
When the downstream acetic acid device is stopped or started for heating, the air release amount is about 6000-
The method is put into use, the recovery is carried out through a fine adjustment valve PV3 during normal production, the average recovery per hour is 450NM3/h, the CO gas 259WNm3 is recovered, the acetic acid is stopped for 7 times, 186WNm3 is recovered through a coarse adjustment valve PV4, the CO gas 445WNm3 is recovered, and the total amount is 356 ten thousand
Without limiting the invention in any way; the method of the present invention may be performed on a device including, but not limited to, those shown in the figures.
While the methods and techniques of the present invention have been described in terms of preferred embodiments, it will be apparent to those of ordinary skill in the art that variations and/or modifications of the methods and techniques described herein may be made without departing from the spirit and scope of the invention. It is expressly intended that all such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and content of the invention.
- 上一篇：一种医用注射器针头装配设备
- 下一篇：一种连续性定量船舶燃料供应系统