Substrate additive for biological depuration.

The study presents the results of testing of a substrate liquid added to a pre-existing system of biological filtration process air of a composting plant. The substrate under test is a mixture of micro and macro nutrients useful to improve the efficiency of degradation in the cases of degradable pollutants from microbial metabolism in the presence of a ratio C : N : P equal to 200 : 10 : 1. The tests were conducted in the field by applying the substrate in liquid form to a biofilter present in a plant for composting. The biofilter involved in the trial receives the effluent gases captured from the section of accelerated bio-oxidation system. The distribution of the substrate was carried out manually above the filter surface and the quantity of substrate used has been established in relation to the pollutant load input to the garrison to environmental and chemical-physical characteristics of the filter material. The effect of the use of the substrate was evaluated in terms of concentration of microorganisms in a cm3 of filter material and the method used for this measurement was that established by Standard EN ISO 6222 of 1999.