In-situ phytoremediation variants for TPH polluted soils

"A mixture of grassland species Lolium perenne, Festuca arundinaceea, Medicago sativa and Ttrifolium pratense were used in situ phytoremediation of oil polluted soil, with 70.45-120.52 g/kg d.m. Total Petroleum Hydrocarbons (TPH). They werestudied variants of phytoremediation of oil polluted soils and fertilized with 50 t/ha stabilized sewage sludge in absence / presence of 50 t/ha fly ash, waste from coal burning power plants. Lolium sperenne herbs formed on the surfaces sown exclusive bouquets, in first weeks. After six weeks of vegetation appear and develop leguminous species Medicago sativa and Trifolium pratense. After five months, was a balanced distribution of species of legumes and grasses species on the surfaces sown. The efficiency reducing the TPH from oil polluted soil was 48.7% in variant fertilized with stabilized sewage sludge and fly ash. Efficiency was with 15.3% higher than the reduction efficiency of petroleum products in fertilized variants in fly ash absence. The process efficiency of oil polluted soil treated with stabilized sewage sludge and fly ash was similarly with phytoremediation variant with fertilizer and indigenous volcanic tuff realized."