發(fā)布時間：2018-01-26 18:54

  本文關(guān)鍵詞： 重復(fù)壓裂 地應(yīng)力 暫堵劑 水溶性 暫堵　出處：《長江大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：油氣藏在不斷開發(fā)過程中,隨著開采次數(shù)的增多,初次壓裂的采油量將不斷降低,又恢復(fù)到最初的低產(chǎn)低效狀態(tài)。如果繼續(xù)采用多次壓裂的常規(guī)方法,將仍是壓開老裂縫,起不到顯著的增產(chǎn)效果。而轉(zhuǎn)向壓裂技術(shù)是目前解決老井低產(chǎn)低效比較行之有效的方法。該技術(shù)的重要機理在于壓裂前向地層擠入一部分暫堵劑暫堵老裂縫,關(guān)井憋壓一段時間后開啟復(fù)雜裂縫網(wǎng)絡(luò),或是將暫堵劑注入孔眼或縫口,迫使其產(chǎn)生新裂縫,進(jìn)而加強新高含油氣區(qū)的“溝通”,提高氣井的改造能力[1]。目前,裂縫轉(zhuǎn)向主要有三種方法:1)地應(yīng)力反轉(zhuǎn);2)定向射孔誘導(dǎo)3)暫堵轉(zhuǎn)向壓裂工藝。本課題從原地應(yīng)力場分析出發(fā)確定了重復(fù)壓裂前儲層的應(yīng)力分布,并建立原地應(yīng)力、初次人工裂縫和孔隙壓力對原地應(yīng)力場影響的計算模型;結(jié)合巖石造新縫力學(xué)分析及裂縫延伸準(zhǔn)則,研究了天然裂縫轉(zhuǎn)向及延伸情況。暫堵劑自身性質(zhì)的優(yōu)良,決定著縫內(nèi)轉(zhuǎn)向壓裂工藝的成功與否,由于受地應(yīng)力場及天然裂縫的影響,暫堵轉(zhuǎn)向劑須具備一些特殊性能。本文測試了幾種新型的水溶性暫堵轉(zhuǎn)向試劑,通過對它們的靜(溶解性、配伍性、表面活性等)、動(暫堵率、解堵率測定)態(tài)室內(nèi)評價實驗研究,以及對影響其暫堵效果的工藝因素試驗研究,篩選出SC-JXSG、BJ-APJEL兩種滿足暫堵壓裂施工現(xiàn)場要求的高效暫堵劑。該實驗結(jié)果表明:(1)靜態(tài)評價實驗中,質(zhì)量分?jǐn)?shù)為3%的SC-JXSG和BJAPGEL兩種暫堵劑在30℃時溶解緩慢,60℃~80℃時數(shù)小時能充分溶解;最終不溶物含量都較低,最大值僅為5.19%,(2)動態(tài)評價實驗中,在60℃條件下,注入1PV質(zhì)量分?jǐn)?shù)為3%的SC-JXSG和BJ-APGEL兩種暫堵劑,暫堵率可高達(dá)98%;在80℃條件下,反向注入10PV地層水解堵,但解堵效果不是很好,位于50%~80%之間。對比裂縫暫堵和基質(zhì)暫堵,SC-JXSG暫堵劑對裂縫的暫堵效果較好,BJAPGEL暫堵劑對基質(zhì)的暫堵效果較好。
[Abstract]:In the process of oil and gas reservoir development, with the increase of production times, the oil production of initial fracturing will be reduced continuously, and then the initial low production and low efficiency will be restored. If the conventional method of multiple fracturing is adopted, the conventional method of multiple fracturing will continue to be adopted in the process of oil and gas reservoir development. Will still be to open the old crack. The technology of turning to fracturing is an effective method to solve the problem of low productivity and low efficiency in old wells. The important mechanism of this technique is to squeeze a part of temporary plugging agent into the formation before fracturing to temporarily block the old fracture. The complex fracture network is opened after shut-in for a period of time, or the temporary plugging agent is injected into the hole or fracture mouth, forcing it to produce new fractures, thus strengthening the "communication" in the high oil and gas bearing area and improving the ability of gas well transformation. [1. At present, there are three main methods of fracture turning: 1) inversion of in-situ stress; 2) directional perforation induces 3) temporary plugging turns to fracturing technology. Based on in-situ stress field analysis, the stress distribution of reservoir before repeated fracturing is determined and the in-situ stress is established. The primary artificial fracture and pore pressure on the original stress field calculation model; Combined with rock fracture mechanics analysis and fracture extension criterion, the natural fracture turning and extending conditions are studied. The good properties of temporary plugging agent determine the success of in-fracture steering fracturing process. Due to the influence of in-situ stress field and natural cracks, the temporary plugging steering agent must have some special properties. In this paper, several new water-soluble temporary plugging reagents were tested, and their static (solubility, compatibility) were tested. SC-JXSG was screened out by surface activity isochron, dynamic (temporary plugging rate, plugging removal rate measurement) indoor evaluation experiment, as well as the experimental study on the technological factors affecting its temporary plugging effect. BJ-APJEL two kinds of high efficiency temporary plugging agents which meet the requirements of temporary plugging fracturing site. The experimental results show that in the static evaluation experiment. Two temporary plugging agents, SC-JXSG and BJAPGEL, with a mass fraction of 3%, dissolve slowly at 30 鈩，

本文編號：1466338