Study And Application Of A Transition Layer Depressant Used For Electric-chemical Dehydration System

Oil/water transition layer emulsion is a yellow-brown,gray-black, heavy oil-like liquid. Its interface is O/W and W/O emulsions, and adsorbs on iron agitators. The middle transition layer consists metal sulfured, natural emulsifier naphthenic acid from crude oil, emulsifiers added, little amount of mechanical admixture and heavy oil. These materials distributes in the coming liquids of oilfield combination station and dehydrated crude oil, they have thecharacteristics of strong conductivity and irreducible water effect.Study on depressing mechanism of depressant includes physical and chemical aspects. The physical aspect includes using interface matter substitution, lowering interfacial tension, extraction and the principle of"like dissolves like"; the chemical aspect is to using higher oxidation method, conversion of chlating and precipitation, replacement reaction, et al. The composition of the depressant were optimized by uniform design and optional mixture ratio were determined: main constituent 35%～45%, mixed solvent 50%～60%, catalyst 2%～15%.The field application experiment of oil/water transition layer depressant was the key to determine the effectiveness of transition layer depressant .Through the tracking study and investigation of ways and amounts of adding chemicals, processing parameter of the experiment station, results showed that with the site of adding chemicals unchanged, the amounts of adding chemicals unchanged or lowered, the oil water separator and electric-chemical dehydration system run evenly.