八面河油田南区注入水管网结垢成因分析

Analysis of Scale Formation of Water-Flooding Pipe Network in Southern District of Bamianhe Oilfield

八面河油田南区注水管网结垢严重,管线普遍结垢。从沿程水质监测指标来看,平均结垢率普遍大于标准值0.1mm/a,严重影响了开发效果。通过对注水管网中垢物组成、注入水水中悬浮物组成进行分析,认为南区联合站三相来水中存在大量铁质,注入水中的成垢离子在阻垢剂的作用下形成的螯合物随注水线路输送至各个注水井,在输送过程中,水中的铁锈、粘土、泥渣等同时受到重力沉降和水流剪切等相互作用逐步附着在注水管内壁,油含量增加导致水中悬浮物也更加容易吸附在管内壁,从而形成以铁化合物为主,间杂少量油质、泥质硅盐及无机盐的垢。

Severe scaling has come up in waterflooding pipe network in Southern District of Bamianhe Oilfielck Ac- cording to water quality monitoring index along the network, average scaling ratio is larger than standard value O. 1 mm/a, having great influence on development results. Through analysis of scaling components in the network and suspending components in injected water, the author believes that three--phase water of multi--purpose station in Southern District contains plenty of irom scaling ions in injected water, under the action of scale inhibitor, will form chelate that is migrated to each injection well along the waterflooding line and in the process of migration, iron rust, clay and sludge will be attached to the inner wall of waterflooding pipe due to simultaneous interaction of gravity set- tling and flow shear; and oil increase will make suspending solids absorb on the inner wall more easily, resulting in the scale in which iron compound makes up the majority mixed with a small amount of oily and muddy silicon as well as mineral salt.