METHOD FOR SCALE REMOVING FOR GEOTHERMAL WELL AND RECOVERY OF REDUCING CAPACITY FOR INJECTION WELL BY USING JET PERFORATOR

摘要

PURPOSE:To remove scales simply and at low costs and to check attenuation of reducing capacity, by performing a reducing capacity test of an injection well and by blasting with shaped explosives inserted into the well after cooling the parts narrowed by scales accumulated in the bore of a geothermal well. CONSTITUTION:First, reducing capacity test 2 is performed for an injection well 1, and temperature logging 3 is performed for the parts whose bores have been narrowed by the accumulation of scales inside a geothermal well. When the temperature exceeds the maximum permissible limit, cooling 5 by cooling water is executed. Then, the state of accumulation of scales is measured at desired spots by means of caliber logging 6 or the like. Next, availability 7 of insertion of a perforator is examined and the depth of blasting is determined 10. Then, a jet perforator is inserted 19 to execute a blasting 20 with explosives. After the blasting, the reducing capacity is tested 21 again for the evaluation of reducibility.