Dynamics of the infiltration of liquid pollution into the ballast section of a railway track within the framework of Forchheimer’s law

Summary

The dynamics of a liquid layer infiltration into porous soil induced by the gravitational forces is considered within the framework of the two-term filtration law (Forchheimer’s filtration law). Simple formulas are obtained for the time dependence of the height of the liquid layer on the soil and the time of complete infiltration of liquid into the soil on the filtration coefficient and porosity of the soil. It is shown that the total infiltration time is directly proportional to the height of the initial liquid layer on the ground. Calculations of the time and average speed of complete infiltration for typical soils were carried out.

Key words

infiltration , ballast section , liquid pollution , body of ballast , porous soil , infiltration time , porosity , filtration of coefficient

Treatment of municipal solid waste landfill leachate

Summary

A review of the international sources of information on the treatment of municipal solid waste landfill leachate is presented. The leachate of municipal solid waste landfill is a type of wastewater characterized by small variable volume and complicated chemical composition. The technologies of leachate collection and treatment overseas have been continuously improved. The processing schemes are, as a rule, combinations of biological, physical, chemical, and membrane processes. The most perspective in this field are SBR-reactors, membrane bioreactors, reverse osmosis units and ozonation systems. Leachate recycling and combined treatment with municipal wastewater, traditional aerobic and anaerobic processes, sedimentation lagoons and phytoremediation are also used. The process flow schemes include the processes of coagulation, flotation, chemical precipitation and adsorption.

Key words

filtrate , municipal solid waste , landfills , infiltration , environmental pollution , leachate treatment technologies