浅埋高硅铸铁阳极地床降阻技术在库鄯输油管线阴极保护工程中的应用

REDUCTION OF RESISTANCE FOR SHALLOW BURIED HIGH SILICON CAST IRON ANODE IN CATHODIC PROTECTION OF OIL PIPELINE FROM KURLE TO SHANSHAN

通过模拟试验,筛选出了由聚丙烯酰胺、三乙醇胺、工业细盐、缓蚀剂及水组成的降阻剂及其最佳配比.接着,在鄯善末站开展浅埋式阳极地床工业性试验.经一年的多次测试结果表明,单根(?)150mm×1500mm的高硅铸铁阳极的接地电阻力3.9～8.4Ω,为不用降阻剂时的1/5～1/8.阳极地床由浅埋20根阳极组成,阳极间距5m,接地电阻稳定在1.3～1.8Ω之间,能满足≤2Ω的技术要求,具有工程实用价值.在此基础上,及时更改了设计,在库鄯管线需采用外加电流法实施阴极保护的约276km长的管段,4处辅助阳极地床施工均采用了浅埋阳极降阻技术.

In ordrt to reduce the groundbed resistance of a single cast iron anode buried in dry soil for impressed current cathodic protection of oil pipeline, a mixture consisting of polyacrylamide, triethanolamine, table salt, inhibitor and water in proper proportion was formulated by laboratory screening and pilot tests at Shanshan in Xingjiang. The mixture filled the anode groundbed. It was indicated by several measurements in one year that the grounded resistance of a single anodeф150mm× 1500mm was 3. 9～8. 4Ω,equivalent to 1/5～1/8 of the resistance without resistance reductin mixture. In the practical project, 20 anodes were arranged in parallel and spaced about 5m apart. The resulting groundbed resistance was 1. 3-1. 8Ω only. The cathodic protection system operated well.