Analysis of growth drive breakdown by the increase of the Dashav UGS fountain pipes

Abstract

Scientists who were analyzing the results of the underground gas storage (UGS) complex of Ukraine, say that for modern conditions the maximum daily productivity should be increased by 30-35%. Since the beginning of the creation of gas storage facilities passed than 40 years, work is carried on outdated and physically worn out equipment. Work of the wells (which were build based on the old technologies at low reservoir pressure) are characterized by low productivity because their bottomhole zone is partially occluded by the mud filtrate, partially contaminated with compressor oil; due to the selective placement of wells in the underground storage area, some of them were formed so-called "stagnant" zones; extraction of all active gas volume which takes 100-180 days. Need for Ukraine to further develop underground gas storage should be aimed at increasing both the active volume of gas and the daily productivity of gas storage facilities. The main directions of increasing the productivity of gas storage are the drilling of horizontal shafts in both new wells and old ones in experience [9], the formation of open holes in the drilling of new wells and the milling of operational columns in the "old" drilled holes, filters, hydraulic fracturing, construction of large diameter wells, additional perforation of gas-saturated intervals. Nowadays, the most important problem is the reconstruction and modernization of existing underground storage facilities through replacement of equipment. This will not only save the achieved performance, but also can improve it. Due to the reconstruction of the equipment, gas preparation will be improved, gas storage capacity will be increased and operating costs will be reduced. Therefore, an increase in the daily productivity of UGS can be achieved, first of all, due to the improvement of the main element in the gas storage facility - the operational well. In order to analyze this issue, the paper analyzes the efficiency of replacing the fountain pipes of the Dashavsky UGS wells with a larger diameter, and presents the results of the hydraulic, technical and economic calculation of the implementation of this UGS reconstruction.