空气泡沫钻井液回收再利用技术

空气泡沫钻井液是低压裂缝性地层较好的防漏钻井液，但它一次性使用，配制工作量大，需水量大，材料消耗多，成本高。若实现空气泡沫的回收再利用，可以大幅度降低单井钻井液成本。泡沫回收使用的关键技术是控制合理的半衰期，根据泡沫出口状态及时调整配方，使泡沫既要满足清洁井眼的需要，又要能及时回收。中油长城钻井公司在伊朗TBK气田的空气钻井过程中，制定了泡沫回收工艺和回收泡沫的性能调整方法。通过泡沫的回收使用和配方改进，泡沫钻井液材料成本降低了三分之二，节约合同钻井液费用346万美元，节约预算钻井液费用1208万美元，并大大缓解了供水紧张的矛盾，减少了钻机停等时问，效益显著。

Recovery and Reuse of Air-Foam Drilling Fluid

Air-foam is a drilling fluid with lost circulation prevention ability in low pressure fissure reservoirs but it can be used only pass from standpipe to on surface then is discarded into dump pit so that it needs enormous volume prepared, consumes abundance of water and ingredient additives, costs high. Therefore reuse of this fluid recovered can greatly reduce the drilling cost. The key for the foam reuse consists of the rational control of its half-life period that needs to adjust the state and the formulation of the foam at its return on surface so that it can meet the requirements on borehole cleaning and e technology of the on- time recovery. Great Wall Drilling Company figured out a technology of foam recovery and property adjustment of the foam recovered and by the application of this technology, the cost of the additives and materials consumed and saved 346 million USD on mud cost and about 1208 million USD on drilling cost therefore the water provision difficulty was greatly relieved, the drilling rig stop and waiting time was evidently reduced and the operation effectiveness was prominently enlarged.