Research With Hot Water Washing Treatment Of Oily Sludge

The oily sludge is one of the major pollutants in petro-chemical industry, which mainly come from the exploration and development industry and petroleum chemical industry production process of the sludge, oil sands, has generated a large amount of high oil content, heavy oil fraction high utilization means less difficult to deal with the characteristics of those treated sludge is not directly discharged into the environment would seriously endanger the safety of the environment and human health, therefore, at home and abroad are actively taking a variety of response measures which are expected to ease with the harmful effects of the oil sludge.The paper outlines the sources of oily sludge, classification and danger, and mainly introduces the oil sludge processing technology of the current domestic and foreign. The oil lays for a long time, the parts of it has formed a kind of thin membrane on the surface of the sludge, so using the heat alkaline surfactant solution washing oily sludge.The test select a different reagent washing oily sludge which oil rate is 50.36%, to residual oil rate as an indicator, respectively research the change of reaction temperature, reaction time, liquid-solid mass ratio, the mass fraction of solution have influence on washing efficiency. Comparison of different reagents washing effect in optimum conditions of each reagent. Using the anionic surfactant ABS and Na2SiO3 mix with a variety of nonionic surfactants, at a fixed experimental conditions to be re-equipped with a set of better performing formula is: ABS: Na2SiO3 : Peregal-20 is 1:2:1. Orthogonal to the formula derived from tests, to determine the optimal experimental conditions, as well as the washing effect of various factors on the degree of influence, Orthogonal experiments showed at the conditions of reaction temperature is 70℃, reaction time is 30min, liquid-solid mass ratio is 5:1, the oil recovery rate is 99.35%. material balance for oily sludge after washing, 89.82% oily sludge had been recovered, mud phase containing 0.51% of oil, measuring the chemical oxygen demand of water is 1600mg/L, mud phase and water phase did not reach the emission standards, needing continue treatment. Finally, supercritical water oxidation for sludge after treatment, at the conditions of reaction temperature is 420℃, reaction pressure is 25MPa, reaction time is 10min, the ratio of oxidant peroxy is four, the removal rate reached 95.5%, so that the residual oil rate of sludge is less than 0.3%, reached the discharge standard of agricultural sludge, the COD value of water is 100mg/L, achieved the "Integrated Wastewater Discharge Standard" (GB8978-1996), realized the water phase and mud washed harmless treatment.