Corresponding author: Zhan Yali , wylzhan@cup.edu.cn
About the author: Wang Xin (1987—), female, doctor, lecturer. Research direction: Environmental pollution chemistry. E-mail: cherish8703@163.com
- Received Date: 2021-02-04
- Acceptance Date: 2021-03-05
- Online Publication Date: 2021-07-23
Key words: - Refining and Chemical Sewage Plant /
- Stench /
- Theoretical odor concentration /
- Health risks /
- Control Strategy
Abstract: Taking the sewage treatment plant of a refinery and chemical enterprise as the research object, the composition characteristics and health risks of the exhaust gas outside the odor control facility were analyzed. The malodorous substances in the external exhaust gas are mainly ammonia, hydrogen sulfide, total non-methane hydrocarbons, aromatic hydrocarbons, and organic sulfur compounds; among them, ammonia, hydrogen sulfide, methyl mercaptan, methyl sulfide, dimethyl disulfide, carbon disulfide and The concentration of 4-ethyltoluene is higher than the odor threshold; the theoretical odor concentration of methyl mercaptan and hydrogen sulfide is the highest, and they are the key odor-causing substances; The contribution rate is the highest (77%); in the external exhaust gas, the non-carcinogenic health risk index (HI total ≈10 −4 ) and lifetime carcinogenic risk (LCR total ≈10 −8 ) of 20 malodorous pollutants are low.
- Received Date: 2021-02-04
- Acceptance Date: 2021-03-05
- Online Publication Date: 2021-07-23
- Key words:
- Refining and Chemical Sewage Plant /
- Stench /
- Theoretical odor concentration /
- Health risks /
- Control Strategy
Abstract: Taking the sewage treatment plant of a refinery and chemical enterprise as the research object, the composition characteristics and health risks of the exhaust gas outside the odor control facility were analyzed. The malodorous substances in the external exhaust gas are mainly ammonia, hydrogen sulfide, total non-methane hydrocarbons, aromatic hydrocarbons, and organic sulfur compounds; among them, ammonia, hydrogen sulfide, methyl mercaptan, methyl sulfide, dimethyl disulfide, carbon disulfide and The concentration of 4-ethyltoluene is higher than the odor threshold; the theoretical odor concentration of methyl mercaptan and hydrogen sulfide is the highest, and they are the key odor-causing substances; The contribution rate is the highest (77%); in the external exhaust gas, the non-carcinogenic health risk index (HI total ≈10 −4 ) and lifetime carcinogenic risk (LCR total ≈10 −8 ) of 20 malodorous pollutants are low.
English Abstract
Full text HTML
It is difficult for the sewage gathering and transportation systems and sewage treatment plants of refinery companies to be completely airtight. Pipelines, structures, and equipment all have volatile pollutants that escape from the water body and form waste gas emissions, becoming an important source of odor pollutants for refining and chemical enterprises. To this end, the sewage treatment plant odor pollution has become an important part of pollution prevention and control system in petrochemical enterprises [ 1 - 2 ] . There are two types of odorous gases emitted by sewage treatment plants: one is the high-concentration odor emitted from physical and chemical facilities, slop tanks, scum pools, etc. The composition is mainly non-methane total hydrocarbons, hydrogen sulfide, ammonia, and organic sulfur. The concentration of malodorous substances such as chemical substances is also relatively high; the second is the low-concentration odor emitted from biochemical facilities and sludge ponds (rooms). High-concentration odors are suitable for treatment by combustion methods (catalytic oxidation combustion, thermal storage oxidation combustion, etc.). Low-concentration odors are mostly treated with lye washing, adsorption and biological deodorization [ 3 ] .
There are strict requirements for source control and emission reduction of odor pollution at home and abroad [ 4 ] . Refining and chemical enterprises have fully implemented the "Petroleum Refining Industry Pollutant Discharge Standard" (GB 31570-2015), and the benzene (4 mg·m −3 ), toluene (15 mg·m −3 ) and toluene (15 mg·m −3 ) of the waste water treatment organic waste gas collection and treatment device have been fully implemented. ), xylene (20 mg·m −3 ) and non-methane total hydrocarbons (120 mg·m −3 ) have all put forward specific requirements and higher standards. Compared with the "Emission Standard of Odor Pollutants" (GB 14554-1993), the "Emission Standard of Odor Pollutants (Draft for Comment)" (2018 Edition) has made stricter regulations on the emission limits of 8 odor pollutants.
Previous studies pay more attention to the composition of characteristic odor of gas treatment facilities released, the main purpose is to provide a basis for odor removal process design [ 3 , 5 - 6 ] , while emissions odor control facilities, gas composition and health risk assessment, the Less research. This study took a sewage treatment plant of a northern refinery and chemical enterprise as the research object, and conducted a comprehensive analysis of the external exhaust gas composition characteristics of three sets of odor control facilities, determined the key odor-causing compounds, and evaluated the comprehensive odor pollutants. Health risks, and put forward corresponding pollution control strategies in a targeted manner, in order to provide a reference for the further improvement of the management and prevention and control of odor pollution in refining and chemical enterprises under the new standard.
It is difficult for the sewage gathering and transportation systems and sewage treatment plants of refinery companies to be completely airtight. Pipelines, structures, and equipment all have volatile pollutants that escape from the water body and form waste gas emissions, becoming an important source of odor pollutants for refining and chemical enterprises. To this end, the sewage treatment plant odor pollution has become an important part of pollution prevention and control system in petrochemical enterprises [ 1 - 2 ] . There are two types of odorous gases emitted by sewage treatment plants: one is the high-concentration odor emitted from physical and chemical facilities, slop tanks, scum pools, etc. The composition is mainly non-methane total hydrocarbons, hydrogen sulfide, ammonia, and organic sulfur. The concentration of malodorous substances such as chemical substances is also relatively high; the second is the low-concentration odor emitted from biochemical facilities and sludge ponds (rooms). High-concentration odors are suitable for treatment by combustion methods (catalytic oxidation combustion, thermal storage oxidation combustion, etc.). Low-concentration odors are mostly treated with lye washing, adsorption and biological deodorization [ 3 ] .
There are strict requirements for source control and emission reduction of odor pollution at home and abroad [ 4 ] . Refining and chemical enterprises have fully implemented the "Petroleum Refining Industry Pollutant Discharge Standard" (GB 31570-2015), and the benzene (4 mg·m −3 ), toluene (15 mg·m −3 ) and toluene (15 mg·m −3 ) of the waste water treatment organic waste gas collection and treatment device have been fully implemented. ), xylene (20 mg·m −3 ) and non-methane total hydrocarbons (120 mg·m −3 ) have all put forward specific requirements and higher standards. Compared with the "Emission Standard of Odor Pollutants" (GB 14554-1993), the "Emission Standard of Odor Pollutants (Draft for Comment)" (2018 Edition) has made stricter regulations on the emission limits of 8 odor pollutants.
Previous studies pay more attention to the composition of characteristic odor of gas treatment facilities released, the main purpose is to provide a basis for odor removal process design [ 3 , 5 - 6 ] , while emissions odor control facilities, gas composition and health risk assessment, the Less research. This study took a sewage treatment plant of a northern refinery and chemical enterprise as the research object, and conducted a comprehensive analysis of the external exhaust gas composition characteristics of three sets of odor control facilities, determined the key odor-causing compounds, and evaluated the comprehensive odor pollutants. Health risks, and put forward corresponding pollution control strategies in a targeted manner, in order to provide a reference for the further improvement of the management and prevention and control of odor pollution in refining and chemical enterprises under the new standard.
No comments:
Post a Comment