The use of treated phenolic industrial effluents for process water supply of coking plants

Summary

The technology of using phenolic effluents after activated sludge treatment for process water supply at coking plants for wet scrubbing of flue gases from drying shops of coal-cleaning facilities, and also in coke departments for flushing cyclones for aspiration system washing and coal flotation is considered. It is shown that the use of the entire volume of the effluent after biochemical remediation in coking plant process water supply makes it possible to improve by 23–26% the efficiency of dust separation equipment eliminating coal and coke from atmospheric emissions; to provide for tertiary treatment of wastewater by adsorption on coke and coal dust. The introduction of the technology allows saving 2.1 mln m3 of process water annually.

Key words

coking plant , biochemical cleared sewage , aspiration system , scrubber , purification of atmospheric emissions , coal and coke dust , coal flotation

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

Reconstruction of the sludge incineration plant at the Central wastewater treatment facilities in St. Petersburg

Summary

The need for the reconstruction of the wastewater sludge incineration plant at the Central wastewater treatment facilities of St. Petersburg is substantiated. A short description of the technological processes of sludge incineration, flue gas purification and treatment of wash water generated in the process of gas purification is given. The advanced technologies of sludge pretreatment before incineration, flue gas purification, heat utilization, electric energy generation are presented. The results of the biochemical, toxicity, chemical and radiological studies carried out in SUE «Vodokanal of St. Petersburg» showed the possibility of using wastewater sludge incineration ash in the production of constructional materials. Cementing properties of ash that improve the structure and quality of constructional materials were determined. The use of ash in the production of concrete and bitumen concrete in amount of 10–12% of the concrete weight is also promising. The use of ash will improve the concrete strength by increasing the imporosity of the poured concrete, bitumen concrete. Solving the task of ash beneficial use will become a concluding stage in the package of measures on wastewater sludge utilization and will provide for zero waste process of wastewater treatment.

Key words

sludge , wash water , scrubber , sludge drying , incinerator , flue gases , ash , dry matter