Naftos produktais užteršto dirvožemio valymas panaudojant nuotekų dumblą

Šio darbo tikslas buvo įvertinti galimybę panaudoti nuotekų dumblą, valant naftos produktais užterštą dirvožemį. Eksperimentui atlikti buvo panaudota 40 talpų, kurios užpildytos po 5 kg sauso dirvožemio. 20 talpų dirbtinai užteršta dyzelinu (15g/kg ir 30 g/kg) ir 20 talpų žalia nafta (15g/kg ir 30 g/kg) sausam dirvožemiui. Nuotekų dumblo įtaka valomam dirvožemiui buvo nustatoma į valomą dirvožemį, (išskyrus 4 kontrolinius bandinius, kuriuose įterpti tik naftos produktai), įterpus 5 ir 10 % (sauso svorio) nuotekų dumblo iš skirtingų šaltinių (Palangos miesto nuotekų valymo įrenginių ir popieriaus gamybos įmonės nuotekų valymo įrenginių). Viso eksperimento metu stebimos likutinės naftos produktų koncentracijos (dujų chromatografu), matuojamas anglies kiekis bandiniuose (anglies analizatoriumi). „Gabi 5“ programos pagalba atliktas dviejų skirtingų užteršto grunto valymo scenarijų būvio ciklo vertinimas.

Biological method is an effective method of oil polluted soil depuration. Applying the method microorganisms, decomposing various contaminants, are used. The aim of this study was to analyze possibility to use sewage sludge for cleaning oil contaminated soil and assess the effect of different environment cleaning technologies. During the experiment two types of diesel concentration were used for artificial contamination of soil in laboratory conditions of 15 and 30 g/kg for dry soil and two types of concentration of raw oil of 15 and 30 g/kg for dry soil. Two different kinds of sewage sludge were inserted into the polluted soil - from Palanga city sewage and from the paper factory sewage. The concentration of sewage sludge was of 5 and 10% dry sludge per kilo of dry soil. During the investigation residual concentrations of oil products were observed. The state period assessment was made for two different polluted soil depuration scenarios created with the “Gabi 5” program. The results of the experiment revealed that insertion of the sewage sludge into the contaminated soil helped to reach better cleaning effect. Diesel contaminated soil with the concentration of 15 g/kg and 10% which was inserted with Palanga city sewage. The effect of 94% decomposition clarity was reached. Meanwhile at the same rate of initial contamination 30% of decomposition effect was reached. Raw oil polluted soil at the initial concentration of 30% g/kg and 10% Palanga city sewage sludge, 77% of decomposition effect was reached. At the control only 28% of effectiveness took place. After the scenario of the lifecycle assessment using the program “GaBi 5” was made, it revealed that the basic soil cleaning technology has the major effect on the environment.