UDC 628.316.12
Tcherkesov A. Yu.
Iron-catalytic technology for the purification of strong hydrogen
sulfide-containing wastewater from petroleum organic synthesis plants
Summary
Recommendations for the selection of a process flow scheme for the removal of sulfides by the method of iron-catalytic oxidation were developed and theoretically substantiated. The optimal conditions for running the process and utilization of sulfur extracted from wastes in the form of a commercial product were established. The proposed solutions are a new practical direction for improving the methods for removing hydrogen sulfide from concentrated solutions (total H2S is more than 50 mg/dm3). Recommendations for the selection of the optimal parameters of the process and technological schemes of desulfidation by the method of iron-catalytic oxidation were composed. A new no-waste technology for the removal of sulfides from industrial wastewater and solutions by the method of iron catalytic oxidation with the regeneration of the recycling iron hydroxide in the technology of purification with air oxygen and the utilization of sulfur extracted from the wastewater in the form of a commercial product is proposed. Advanced and environmentally friendly process flow schemes for the removal of sulfides field-tested and introduced into the investment project are proposed. Their practical implementation in industrial wastewater treatment will provide for eliminating environmental pollution with H2S and SO2 emissions and obtaining the effluent that meets both the conditions of reuse in oil-and-gas synthesis technology and regulatory requirements for the industrial effluent discharge into the municipal sewer at minimal expense.
Keywords
sulfide-alkaline wastewater , sulfides , hydrogen sulfide , iron-catalytic oxidation of sulfides
|
bbk 000000
UDC 628.237
Fedorov Sviatoslav Viktorovich, Vasilyev V. M., Klementyev M. N.
Study of gas evolution in a sewer section
Summary
Transportation of wastewater through sewer networks is accompanied by the generation and evolution of gases from the flow. For a quantitative assessment of the gas evolution process a sewer section model has been developed in the ANSYS CFX finite element analysis package. The model takes into account the combined flow of wastewater, entrained air and sewage gas (e.g. carbon dioxide) coming from the collector tray. Monitoring was carried out in a section of the domestic sewage system (DN = 500 mm) in the industrial zone of Obukhovo in St. Petersburg. The measured values of the vacuum pressure are in the range of model calculations. The process of designing a computational area of the sewer section and establishing initial and boundary conditions is presented. As a result of modeling the dependences of the carbon dioxide concentration and the pressure of the gas-air environment in the underroof space of the pipeline with different slopes and filling levels were obtained. The results obtained can serve as a basis for the approach to predicting the process of gas evolution in sewer sections.
Key words
monitoring , simulation , ecological safety , sewerage network , carbon dioxide , hydrogen sulfide , methane , ammonia , gas evolution intensity
Скачать/download (PDF) free access
|
DOI 10.35776/VST.2021.01.01
UDC 628.167.069.84
Tcherkesov A. Yu., Shchukin S. A., Denisova Irina
Study of the catalytic iron oxidation of hydrogen sulfide by air oxygen in a reactor with a membrane separator
Summary
The results of studies of the catalytic iron oxidation of hydrogen sulfide by air oxygen in a reactor with a membrane separator are presented. The studies were carried out in a laboratory setup. An artificially prepared model hydrogen sulfide-containing water served as the object of study. The laboratory setup was a reactor vessel where hydrogen sulfide was oxidized by air oxygen in the presence of iron hydroxide that acted as a catalyst for the process. The separation of purified water and Fe (OH)3 was carried out by ultrafiltration. All the experiments were executed under the conditions recommended for the iron catalytic oxidation of hydrogen sulfide: concentration of iron (III) hydroxide 2 g/dm3, pH 7–8, residence time in the reactor 1 hour, air consumption 2 m3/m3, temperature 20–23 ºС. The oxidizing ability of the method has been experimentally confirmed at the above standard values of the indicators. A regression equation has been obtained that describes the catalytic oxidation of hydrogen sulfide by air oxygen in a reactor with a membrane separator. The presented method can be recommended in the process flow schemes of natural hydrogen sulfide-containing water purification for the purposes of drinking water supply.
Key words
ultrafiltration , sulfide-alkaline wastewater , hydrogen sulfide , membrane separation , air oxygen , iron hydroxide
|
DOI 000000
UDC 628.237.2:628.521
Tcherkesov A. Yu., Shchukin S. A., Israilov R.
Study of removing hydrogen sulfide from ventilation
and sewage gas-air emissions by absorption cleaning
Summary
The results of studying the removal of hydrogen sulfide from ventilation and sewage gas-air emissions by absorption cleaning on a packing irrigated with sodium hypochlorite are presented. The studies were carried out in a laboratory setup. The subject of research was artificially prepared gas mixture of air and hydrogen sulfide obtained by dosing hydrogen sulfide solution into acidic solution (gas generator). Variation of the hydrogen sulfide concentration in the air was achieved by changing the feed from a hydrogen sulfide-containing solution dispenser. The laboratory setup included an absorber with a volumetric packing made on the model of Raschig rings. Chlorine-containing 0.3% sodium chloride solution was used as the absorption solution. The regeneration of active chlorine (reduced by hydrogen sulfide to chlorides) in the absorbent was carried out by direct electrolysis in a flow-through electrolyzer installed in the line supplying the absorbent to the absorber. The actual dose of active chlorine for the oxidation of hydrogen sulfide absorbed by the absorbent was determined. The main dependences describing the chemisorption of hydrogen sulfide and the electrochemical regeneration of sodium hypochlorite in the absorbent are presented. A method for calculating the absorber of the laboratory setup is presented. Specific electricity consumption for removing hydrogen sulfide from air was determined. In the follow-up studies the obtained results will provide for calculating the costs of air purification, estimating the operating costs and conducting an engineering and economical comparison of the proposed and competing methods of removing malodorous substances from ventilation emissions from sewer facilities. The presented method can be recommended in the schemes for cleaning ventilation emissions at the wastewater treatment facilities.
Key words
sodium hypochlorite , reeking substances , hydrogen sulfide , absorption , cleaning of ventilation emissions
|
bbk 000000
UDC 628.34
Fedorovskaya T. G., Koudryashova G. N.
On high alkaline sulfide-containing wastewater treatment
Summary
One of the main problems experienced during tannery wastewater transportation and treatment is hydrogen sulfide release that causes pipeline corrosion, gas contamination of premises and wastewater treatment facilities territory. The methods of sulfide-containing wastewater treatment have been well investigated; however, the reason of hydrogen sulfide release is still urgent and needs explanation. Theoretic and experimental studies carried out at the Moscow State University of Civil Engineering allowed explaining the reasons of hydrogen sulfide release from high alkaline solutions. Experimental studies with standardized test solutions of sodium sulfide showed that their alkalization inhibited hydrogen sulfide release, however required large amounts of alkaline agent and could be hardly adopted for practical use.
Key words
cleansing , wastewater , hydrogen sulfide , tannery , sulfide , high alkaline solution
|
bbk 000000
UDC 504.3.054:628.316.7
Bogomolov M. V., Gavrilin A. M., Agevnin A. R., Kireyev Ju. P., Maleyeva A. V.
Field trials of wastewater air-gaseous emissions odor control technologies
Summary
The advanced technologies of removing nuisance odors from wastewater gaseous emissions are considered. The results of field trials of adsorption filters for the sewer vents and biological odor control systems for the manholes at Mosvodokanal MPUE facilities are described. For some years Mosvodokanal is developing optimal wastewater odor control methods. International experience is studied; investigations, experiments and pilot tests are carried out.
Key words
sewerage network , adsorption filter , biological odor control , hydrogen sulfide
|
UDC 628.237.2:628.521
DOI 10.35776/VST.2023.10.03
Tcherkesov A. Yu., Israilov R.
Removing malodorous substances from gas-air mixtures in wastewater disposal systems
Summary
A scientific justification is given for the use of the method of hydrogen sulfide absorption by aqueous media containing an oxidizer – hypochlorite ion, obtained electrochemically in a stream of reusable absorption solution, in a countercurrent absorber for gas-air mixture purification in wastewater disposal systems. The results of theoretical and experimental studies of the influence of operational factors on the efficiency of removing hydrogen sulfide from gas-air mixtures using the proposed method are presented. Recommendations for using the method are given. A process flow scheme for gas-air mixture purification in wastewater disposal systems using the method of hydrogen sulfide absorption by aqueous media containing an oxidizer – hypochlorite-ion, as well as the process parameters for its application, are presented. The results of estimating the economic efficiency of the developed technology are provided.
Key words
sodium hypochlorite , hydrogen sulfide , absorption , gas cleaning , absorbent , absorber
|
bbk 000000
УДК 628.16.094.3:66.074.371
FESENKO L. N., Tcherkesov A. Yu., Ignatenko S. I., Shchukin S. A.
Purification of hydrogen sulfide containing natural water
by iron-catalytic oxidation in a reactor with unltrafiltration separation
Summary
Currently purification of hydrogen sulfide containing water has been still a bottleneck in water treatment and demands advanced high-efficient technologies, equipment and plants providing for solving at the same time drinking and environmental aspects. The technology based on iron-catalytic oxidation of sulfides in the presence of atmospheric oxygen and combined with membrane treatment is proposed as an advanced technology of hydrogen sulfide removal from natural water. The data on practical testing the proposed technology in a laboratory unit is presented. Subsequent to the results of the experimental studies the area of the developed technology application in purification of hydrogen sulfide containing natural water is substantiated. The absence of accompanying hydrogen sulfide emission from the reactor in the process of water purification and environmental safety has been noted. Based on the obtained results the technology is considered for today as possible and essential. Herewith further study with investigations directed at determining the optimal process parameters is needed.
Key words
natural water , water treatment , hydrogen sulfide , iron-catalytic oxidation of sulfides , membrane separation
|
UDC 628.237.2:628.521
DOI 10.35776/VST.2024.06.06
Vasiliak L. M., Sobur Denis
Why is ozone not used in world practice to control odors
from the wastewater disposal system?
Summary
The reasons that limit possible using ozone to remove hydrogen sulfide and other malodorous substances coming from the wastewater treatment facilities and wastewater pumping stations are analyzed. It is shown that one of the main disadvantages is the long time required to remove malodorous substances to the required low concentrations. The main reaction of ozone interacting with hydrogen sulfide is presented, its rate is analyzed, and it is shown that the typical duration of the reaction ranges from tens of minutes to several hours. The difficulties of using ozone to remove hydrogen sulfide, associated with the chemical resistance of the latter, are presented. The ozone concentrations required for the effective cleaning, and the number of ozone molecules consumed to remove one hydrogen sulfide molecule are estimated. Data are provided on the use of ozone to remove volatile organic compounds, including phenol and formaldehyde. Issues related to the disposal of reaction products and safety precautions of ozone use are also discussed.
Key words
ozonization , air cleansing , sewerage treatment facilities , hydrogen sulfide , ozone , odors
|
bbk 000000
UDC 628.21:661.9
Kofman V. Ya.
Hydrogen sulfide and methane in the sewer networks (review)
Summary
International experience of using methods of protecting from hydrogen sulfide and methane generation in sewer networks is presented. The efficiency of using reagent methods and their cost depend to a great extent on the parameters of sewer pipelines and wastewater composition. Therefore in order to make a reliable choice of one or another method one should take into consideration the local conditions and carry out relevant tests.
Key words
sewerage network , hydrogen sulfide , methane , reagent method , injection
|
|
