Research Of Long-term Acidizing Plugging Remover For Water Injection Well In Huanbei Block

Huanbei block is the main block that can produce thin oil in Huanxiling Oil Production Plant.In the past its development mainly relied on natural energy,in this way the formation energy could not be added.The water injection development has been adopted in a planed way since 2009,and the effect has been obvious.But the high probability of water injection well being clogged is affected by various factors like stratum,water quality,etc.Through the research of long-term acidizing plugging remover for water injection well in Huanbei Block,we can solve the problems that caused by using conventional plugging remover,and ensure the normal water injection in this block.This paper analyzed and studied on the effect on water injection by water quality and scale.By studying we can know that the corrosion of pipelines and the corrosion products are the main reason that caused the content of suspended solids and oil in water to exceed the standard,in the auxiliary function,scaling product is mainly the silicate scale,aluminum ions.Through the research,the main components of injection wells scale are silicic acid scale and aluminum ion.The measure of various ions in water shows that the positive ion that easy to cause the scaling are mainly Ca2+,the anion are Mg2+,SO42-and CO32-.The experiment synthesizes the long-term plugging remover with excellent performance,and prioritizes the acid water volume fraction of 1:4 long-term plugging remover solution as the main acid.The experiments show that,the main acid corrosion rate on the final sample can reach about 23%,compared with the soil acid,the acid liquid has a slow speed with excellent performance,a greater corrosion rate on quartz,and a low corrosion rate on clay minerals.It can get the result of relieving the deep strata pollution,extending the acidizing distance and prolonging the period of validity,on the other hand,it can also avoid the formation of caves by over acidification near wellbore,and even cause collapse.The main acid has a better complexation property,a well anti two sedimentation performances is good.It can effectively prevent the formation of precipitation and reduce the damage to formation.