On the choice of methods for removing malodorous substances from vent emissions of the transportation and wastewater treatment system

Summary

Over the past seven years, Mosvodokanal JSC has been actively implementing a program on eliminating the emission of malodorous substances at the wastewater transportation and treatment facilities: wastewater treatment facilities, wastewater pumping stations, etc. As part of the program, the necessary covering of open storage tanks (receiving chambers, discharge canals, grit chambers, primary settling tanks, etc.). Various methods of removing malodorous substances have been approbated including experimental-industrial and pilot tests. Based on the results of the field trials of various installations for removing malodorous substances from air, as well as with account of the technical and economic assessment of the operating costs, Mosvodokanal JSC is introducing sorption systems based on the photosorption-catalytic purification method. The implementation of the program ensured a tenfold reduction in the general background of malodorous substances on the premises of the facilities providing for the elimination of odors in the nearby residential areas of the city.

Key words

biofilter , adsorption , scrubber , atmospheric air quality regulations , photosorption-catalytical method , industrial methods of removing malodorous substances , cost of removing malodorous substances , electric-discharge technologies

The use of chemical scrubbers to eliminate odors
at the wastewater treatment facilities

Summary

The potential and features of using chemical scrubbers to remove from the air hydrogen sulfide and other malodorous substances generated during the transportation and treatment of wastewater are considered. A comparative analysis of the characteristics of various types of scrubbers: alkaline, hypochlorite, peroxide, and based on iron compounds is presented. It has been shown that the use of chemical scrubbers to eliminate malodorous substances at the wastewater treatment facilities has a number of significant limitations. The use of chemical scrubbers is advisable at the primary stage of air cleaning. Relatively low concentrations of hydrogen sulfide in the ventilation emissions of the wastewater treatment facilities at the relatively high concentrations of carbon dioxide result in an increase in the consumption of chemicals for second-order chemical reactions. In this case, significant operating and capital costs in the climatic conditions of Russia, except the southern regions, the operation complexity of the equipment, and the need for additional air cleaning using other methods should take into account.

Key words

wastewater , absorption , industrial methods of removing malodorous substances , hydrogen sulfide removal , chemical scrubbers , odor control

Efficiency of gas discharge methods for odor control in municipal wastewater transportation and treatment systems

Summary

In the process of wastewater transportation and treatment malodorous substances are released into the air; among them hydrogen sulfide being one of the most difficult to remove. Various methods are used to remove malodorous substances from the air, including gas-discharge (plasma, ionization) methods that have proven remarkably effective in other industries. Vent emissions generated during wastewater treatment are specified by high humidity, high concentration of hydrogen sulfide, potential explosion hazard. These properties limit the possible use of gas discharge methods for the purification of this type of vent emissions. The specificity of applying gas discharge methods for air purification at the wastewater treatment facilities and wastewater pumping stations is described. The arising technical difficulties are presented.

Key words

wastewater , industrial methods of removing malodorous substances , hydrogen sulfide removal , gas discharge methods of air purification , plasma catalytic air purification