CN-122010320-A - Intermodal system and method for tail gas oxidation absorption process and wastewater double-alkali softening process

CN122010320ACN 122010320 ACN122010320 ACN 122010320ACN-122010320-A

Abstract

The invention relates to the technical field of petrochemical engineering, and particularly discloses an intermodal transportation system and method of a tail gas oxidation absorption process and a wastewater double-alkali softening process, wherein the intermodal transportation system comprises a wastewater treatment device and a tail gas treatment device connected with the wastewater treatment device; the tail gas treatment device comprises a tail gas treatment tower for generating acid wastewater and a liquid discharge pipeline connected with the tail gas treatment tower, wherein a control valve and a filter are sequentially arranged on the liquid discharge pipeline along the flowing direction of the acid wastewater. The invention takes the acid wastewater as the neutralization acid liquor for wastewater treatment, realizes the recycling of wastewater, reduces the consumption of acid and alkali liquor compared with the prior art, and reduces the investment of super stainless steel equipment such as tail gas neutralization storage tanks, tail gas wastewater pump sleds and the like and matched pipelines compared with the prior art by filtering the acid wastewater by a filter and conveying the acid wastewater to an intermediate tank by virtue of the pressure in a liquid discharge pipeline, thereby greatly reducing the cost.

Inventors

LUO YUAN
LU DAYONG
SUN DEBIN
MU BOFENG
ZHANG MIN
ZHAN RUILING

Assignees

中国石油天然气股份有限公司

Dates

Publication Date: 20260512
Application Date: 20241112

Claims (9)

1. An intermodal system of an exhaust gas oxidation absorption process and a wastewater double-alkali softening process is characterized by comprising a wastewater treatment device and an exhaust gas treatment device connected with the wastewater treatment device; the tail gas treatment device comprises a tail gas treatment tower for generating acid wastewater and a liquid discharge pipeline connected with the tail gas treatment tower; and a control valve and a filter are sequentially arranged on the liquid discharge pipeline along the flowing direction of the acid wastewater.
2. The intermodal system of an oxidation absorption process for tail gas and a double alkali softening process for waste water as set forth in claim 1, wherein a liquid level regulating valve is further provided on said liquid discharge line, said liquid level regulating valve being disposed between the control valve and the output port of the tail gas treatment tower.
3. The intermodal system of a tail gas oxidation absorption process and a wastewater double alkali softening process according to claim 1, wherein the wastewater treatment device comprises a reaction tank provided with an alkali liquor injection port, an intermediate tank connected with the reaction tank, and a filter tank connected with the intermediate tank, and the intermediate tank is connected with the output end of a liquid discharge pipeline.
4. The intermodal system of the tail gas oxidation absorption process and the wastewater double-alkali softening process according to claim 3, wherein the reaction tank comprises a double-alkali reaction tank, a PAC reaction tank, a PAM reaction tank and a tube sedimentation tank which are sequentially connected, the tube sedimentation tank is connected with the middle tank, the alkali liquor injection port is arranged on the double-alkali reaction tank, and the alkali liquor inlet and outlet are two groups, including a sodium carbonate injection port and a sodium hydroxide injection port.
5. An intermodal system of an exhaust gas oxidation absorption process and a wastewater double alkali softening process as set forth in claim 3 wherein said filtration tank comprises a multi-media filtration tank connected to an intermediate tank, an ultrafiltration tank connected to the multi-media filtration tank.
6. The intermodal system of tail gas oxidation absorption process and wastewater double alkali softening process as set forth in any one of claims 1-5, wherein the tail gas treatment tower is a venturi tower, the liquid discharge pipeline is made of UPVC material, and the filter is a Y-type filter.
7. An intermodal method of intermodal systems of an exhaust gas oxidation absorption process and a wastewater double alkali softening process according to any one of claims 1 to 6, comprising the steps of: The waste water is treated by a waste water treatment device to generate alkaline waste water which is stored in an intermediate tank; the tail gas treatment tower conveys the acid wastewater to the intermediate tank through a liquid discharge pipeline; Neutralizing alkaline wastewater and high-acidity wastewater in the intermediate tank to obtain a reacted mixed solution; The filter tank will filter the mixture.
8. The intermodal method of intermodal system of oxidation and absorption process of tail gas and double alkali softening process of waste water as claimed in claim 7, wherein said tail gas treatment tower conveys the acidic waste water to the intermediate tank through the liquid discharge pipeline, specifically: The discharge of the acid waste water in the Venturi tower is regulated by the liquid level regulating valve and the control valve so as to keep the liquid level of the Venturi tower stable, and the discharged acid waste water is filtered by the Y-shaped filter and then is conveyed to the middle tank.
9. The intermodal method of intermodal system of oxidation and absorption process of tail gas and double alkali softening process of waste water as set forth in claim 7, wherein said waste water is treated by the waste water treatment device to produce alkaline waste water which is stored in the intermediate tank, specifically: Adding alkali liquor into the double-alkali reaction tank to reduce the hardness of the wastewater after the wastewater enters the double-alkali reaction tank; The treated wastewater enters the inclined tube sedimentation tank, passes through the inclined tube sedimentation tank and then enters the middle tank.

Description

Intermodal system and method for tail gas oxidation absorption process and wastewater double-alkali softening process Technical Field The invention relates to the technical field of petrochemical engineering processes, in particular to an intermodal system and method of a tail gas oxidation absorption process and a wastewater double-alkali softening process. Background Natural gas is used as a low-carbon and environment-friendly clean energy source and is greatly developed by China, a natural gas purification process is widely applied and is controlled by factors such as process flow, parameters and the like, a large amount of high-acidity wastewater can be generated in the operation process of the tail gas treatment device, and the high-acidity wastewater enters the wastewater treatment device for treatment after being neutralized. The wastewater treatment device adopts the processes of double alkali, flocculation, ultrafiltration, resin, reverse osmosis and the like to treat and recycle the wastewater, thereby realizing zero discharge of the wastewater. The existing tail gas and waste water processes adopt independent sectional design modes, are not integrally designed, have long process flow, large equipment and facility investment, high disposable construction investment and daily operation and maintenance cost, generate a large amount of dangerous wastes, and become a difficult problem which puzzles the industry for a long time. The high-acidity waste water of the tail gas of the existing process is discharged to a neutralization storage tank, is added with alkali liquor to neutralize and adjust the pH value to 7-8, is conveyed to a waste water regulating tank through a pump, and then enters a waste water treatment device for treatment, and the waste water treatment device adopts double-alkali, flocculation, ultrafiltration, resin, reverse osmosis and other processes for recycling the waste water (figure 2). Wherein, tail gas treatment device's neutralization storage tank, waste water elevator pump sledge and supporting pipeline adopt corrosion-resistant super stainless steel material, and construction investment and operation maintenance cost are high. Disclosure of Invention The invention aims to solve the technical problems by providing an intermodal system and method for an exhaust gas oxidation absorption process and a wastewater double-alkali softening process, wherein acid wastewater is used as neutralizing acid liquor for wastewater treatment, thereby realizing wastewater reclamation, reducing the consumption of acid and alkali liquor compared with the prior art; the invention solves the technical problems by adopting the following solution: An intermodal system of an exhaust gas oxidation absorption process and a wastewater double-alkali softening process comprises a wastewater treatment device and an exhaust gas treatment device connected with the wastewater treatment device; the tail gas treatment device comprises a tail gas treatment tower for generating acid wastewater and a liquid discharge pipeline connected with the tail gas treatment tower; and a control valve and a filter are sequentially arranged on the liquid discharge pipeline along the flowing direction of the acid wastewater. In some possible embodiments, a liquid level regulating valve is also provided on the liquid discharge line, the liquid level regulating valve being provided between the control valve and the output of the tail gas treatment tower. In some possible embodiments, the wastewater treatment device comprises a reaction tank provided with an alkali liquor injection port, an intermediate tank connected with the reaction tank, and a filter tank connected with the intermediate tank, wherein the intermediate tank is connected with the output end of a liquid discharge pipeline. In some possible embodiments, the reaction tank comprises a double-alkali reaction tank, a PAC reaction tank, a PAM reaction tank and a tube-in-tube sedimentation tank which are sequentially connected, wherein the tube-in-tube sedimentation tank is connected with the middle tank, the alkali liquor injection ports are arranged on the double-alkali reaction tank, and the alkali liquor inlet and outlet are in two groups, and comprise a sodium carbonate injection port and a sodium hydroxide injection port. In some possible embodiments, the filtration tank comprises a multi-media filtration tank connected to the intermediate tank, an ultrafiltration tank connected to the multi-media filtration tank. In some possible embodiments, the tail gas treatment tower is a venturi tower, the liquid discharge pipeline is made of UPVC material, and the filter is a Y-type filter. An intermodal method of an intermodal system of an exhaust gas oxidation absorption process and a wastewater double-alkali softening process according to the above, specifically comprising the following steps: The waste water is treated by a waste water treatment device to generate alkalin