It can reduce different impurities into oil-producing zone: Common string is acidized to extrude all attaching obstacles, waxes and rust slag into formation together with acid liquid. Coiled tubing acidizing can remove rust slag, scale and wax from production string and relieve formation pollutions caused by acidizing.
Small volume of acid liquid and long well section under the impact of acidizing: It is hard for traditional string acidizing to effectively acidize long well sections. Meanwhile, a large of acid liquid is needed. However, coiled tubing acidizing can be
carried out to selectively acidize long well sections, in particular horizontal sections. It not only eliminates formation pollutions effectively but also save acid liquid.
Avoid bringing secondary pollution to oil-producing formations because kill job can be omitted: Quick formation cleaning is one of the efficient methods to promote liquid production. After formations are treated by acid liquid, settlements and liquid leakages appear accordingly. Since coiled tubing is applied, flow displacement can be easily realized by nitrogen and coiled tubing can be pulled out of well without kill job. Coiled tubing is a closed loop system. Operators impose effective control over oil wells and all operations are performed in an operation room to protect themselves from being injured by discharged toxic gases (hydrogen sulfide and sour gas).