Study On Reasonable Working System Of Low - Level Horizontal Well In HQ Oilfield

With the development of petroleum industry, and the deepening degree of exploration and development for domestic oil and gas resources, the probability of founding better geological grade of oil and gas reservoirs is getting smaller and smaller. Low permeability oil and gas field gradually play a very important role in increasing reserves and production. One important characteristic of low permeability oil and gas reservoir is low production and poor economic benefit, Strengthen the research of the exploration and development of low permeability oil and gas reservoirs and meticulous management for low yield region is needed.The horizontal well has the characteristics of high production as to the vertical wells. And so, more and more horizontal wells were drilled in low permeability oil and gas reservoir in order to increase production, improve development efficiency.HQ oilfield is a typical oil and gas zone of low permeability, low pressure and low production. Even if the horizontal well is used in the exploitation, the costs are still high. To reduce the production cost, improving the economic benefit is more important in the realistic situation that crude oil prices remain low for a long time.In this paper, taking the low production and inefficient oil horizontal wells of HQ oil field as the research object. Combining with the actual, with the premise of zero yield loss, studied the method of reasonable intermittent work system.(1) By Collecting and analyzing the geological data, fluid analysis, reservoir physical property data and well production data of HQ oil field, getting a full understanding of the reservoir and production characteristics of the region.(2) Researching and verifying the horizontal well productivity equation, then analyzing the causes of production loss when three phase flow in formation near the bottom. And then, selecting the right dimensionless IPR equation applicable to the gas oil two-phase flow, getting the oil gas and water three phase IPR curve for horizontal wells, with the methods using by Petrobras to calculate the vertical wells inflow performance curve of three-phase flow.(3) Analyzing the influence factors of pump efficiency, summarizing the cause of submergence, gas oil ratio, water content influence the pump efficiency. Combing with the HQ oil field production data, sum up the general law of the relationship between submergence pressure and pump efficiency and the Empirical formula for calculating the pump efficiency.(4) With the relationship between IPR of horizontal wells and the formula of pump efficiency and submergence pressure, optimizing the depth of pump、pump diameter、the maximum value and the minimum value of formation production in the situation of Intermittent production. Selecting the reasonable open time and shut time, to equal the cumulative production of intermittent production and cumulative production of ordinary production.This study provides a theoretical and applied basic for the analysis of inflows and outflows dynamic models of low production and inefficient oil wells of low permeability reserves and the determination of reasonable working system of intermittent oil production.