FIELD: oil industry. SUBSTANCE: process id related to determination of content of petroleum products in natural water and sewage of various enterprises such as oil producing and refining plants, gas-filling stations, etc. Proposed process determining content of petroleum products in water includes three-phase concentration of petroleum products by passage of polluted water through cartridge filled with sorbent on base of silicon dioxide, elutriation, removal of hampering impurities and measurement of content of petroleum products in eluate. In the capacity of sorbent there is proposed to use superfine quartz fibrous material with amorphous structure having specific surface of 2.0 sq m/g and characterized by following distribution of fibers by diameter ( per cent by mass ): 0,0-0,5 mkm-7-14; 0,5-1,0 mkm-31-48; 1,5-2,0 mkm-5,6-22,5; 2,0-2,5 mkm-5,1-8,5; 2,5-3,0 mkm-2,1-7,6; 3,0-3,5 mkm-2,1-2,5; 3,5-4,0 mkm-2,8-3,6; 4,0-4,5 mkm-1,4-2,5; 4,5-5,- mkm-2,1-2,5; 5,0-5,5 mkm-0,7-2,0; 5,5-6,0 mkm-0-0,5; 6,0-6,5 mkm -0-0,7; 6,5-7,0 mkm -1-1,4. EFFECT: improved accuracy in determination of content and possibility of usage of sorbent many times. 7 cl, 8 tbl
