Oil sludge neutralization methods. Neutralization of oil sludge by incineration

Abstract

Oil sludge is a solid or pasty oil-containing waste, which is a heterophase system of organic, water and mineral parts in the form of sand, dust, silt, metal compounds, the ratio of which varies over a very wide range. Oil sludge is formed during the construction of oil and gas wells, during the direct extraction of a useful component, during oil refining, and during the purification of oil-polluted waters and reservoirs. This is a waste that is generated in large enough quantities, for the placement of which areas are alienated for the organization of oil sludge pits, which leads to significant costs for organizations to pay for waste storage. Also, during such storage, damage is also caused to the environment due to the evaporation of oil products from the areas, pollution of soil and water in case of loss of integrity by the insulating material. The objectives of the study were to evaluate the effectiveness of oil sludge neutralization by burning at a temperature of 900°C and to assess the safety of using the resulting ash as a secondary resource for technical needs in oil fields. The following indicators of oil sludge were determined by the author: the amount of oil and oil products — by the gravimetric method, humidity — by the thermogravimetric method, and the content of gross (As, Sb, Sn) and mobile (Co, Cr, Mn, Ni, Zn, Pb) forms of heavy metals — by the method of atomic absorption spectrometry. Based on the nature of the thermogravimetric curve, one can judge the absence of oil and oil products in the ash. When analyzing the content of heavy metals in the ash, a slight excess of the MPC for arsenic (2.77 mg/kg versus 2 mg/kg) and more than 2.5 times for nickel (10.5 mg/kg versus 4 mg/kg), therefore, before using the ash for industrial needs, involving contact with the ground, the ash must be mixed, for example, with sand, in a ratio of 1:2.6, respectively.