Performance Evaluation of Magma Power Company's Reinjection Well No. 46-7 at the East Mesa KGRA, California

摘要

The performance of the Magma Power Company's reinjection well No. 46-7 at East Mesa has been examined. Water was cooled to 100 exp 0 F(+-) to simulate total heat extraction and then tested using membrane filter flow procedures. The cooled water contains particles which are in the high colloid size range, and formation impairment by these particles is unlikely. There is evidence that acid soluble corrosion products and calcium compounds constitute about two thirds of the particulates, and that the acid insoluble residue contains precipitated silica, insoluble corrosion products, and possibly formation fines carried in the produced water. Under stabilized conditions, the suspended solids content of the water is less than 2 parts per million. However, during the frequent production well start ups, a higher concentration of suspended solids is carried in the produced water and into the injection well, conceivably augmenting fill in the injector. But most likely, fill occurs when the injection well surges during shut-downs, because of inadequate sand control in the well completion. At the time of the test, the injection well was found to be severely impaired. Back flowing the well restored the injectivity to a calculated maximum sub-frac injection capacity of about 60,000 b/d of water at T = 350 exp 0 F, which corresponds to a calculated maximum hypofrac injection capacity of about 20,000 b/d of cold water (T = 100 exp 0 F). (ERA citation 05:015596)