PHYSICO-CHEMICAL INVESTIGATIONS FOR THE ASSESSMENT OF THE CHEMICAL SAFETY AND EFFICACY OF APPLICATION OF A NEW SYSTEM OF LANDFILL GAS PURIFICATION AT THE SOLID DOMESTIC GARBAGE DUMP

Abstract

Landfills of municipal solid waste (MSW) have a negative impact on the environment and people: air, soil, surface water and groundwater are polluted. During the storage of MSW in the body of the landfill natural anaerobic decomposition of organic waste takes place under conditions of oxygen lack, high temperature and humidity. One product of this process is landfill gas - a mixture of methane and carbon dioxide with small amounts of impurities (nitrogen, silicon, sulfur, hydrogen sulfide). Tens and hundreds of different organic compounds are also included as a compound of landfill gas. The composition and content of the individual components in landfill gas depends on the composition of landfilled waste at the solid domestic garbage dump. The landfill gas and odor run to great distances. Construction, operation and closure of landfills give rise to a number of environmental problems associated with such a classification of landfills as a secondary source of pollution of the urban environment. The solution of such environmental problems offers a variety of options for the “recovery”, “remediation” and protective measures in areas of placement of landfills. For example, in the landfill “Timokhovo” there were studied the efficacy and safety of a new chemical treatment technologies and disposal of landfill gas As a result of the installation of the system for landfill gas purification there was established the decline in the total concentration of polluting compounds, as hydrocarbons (including saturated and aromatic), alcohols, oxygen and sulfur containing compounds by from 63 to 2200 times. There was reached 100% disposal of mercaptanes, sulfides, di- and trisulfides, naphthenic and terpenic hydrocarbons and chlorinated compounds. The number of identified compounds was reduced by more than 2 times. However, at the output of the purification system there were revealed compounds not identified at the input of this system. It can be regarded due to the appearance of transformation products of flaring hydrocarbons. Gas chromatography-mass spectrometry studies directed to the identification with quantitative assessment of air emissions before and after the new system of utilization allow both perform monitoring emissions taking into account the real content and changes in group and component structure under the influence of the chemical impact of the new technologies and make recommendations for further improvement of gas purification systems in terms of environmental aspects.