【摘要】：固井工程中的注水泥作業(yè)是極為重要的一道工序,為達(dá)到避免鉆井液和水泥漿兩種理化性質(zhì)差異較大的流體產(chǎn)生接觸污染現(xiàn)象,隔離液通常會(huì)先于水泥漿被注入到井段中,并在鉆井液和水泥漿之間形成分隔。但是,現(xiàn)有的隔離液體系大多耐溫性差、與水泥漿、鉆井液不相容、抗污染機(jī)理研究尚不成熟。為此,本文在合成PIAS、流型調(diào)節(jié)劑HS和優(yōu)選其他添加劑的基礎(chǔ)上,研制成了耐高溫的高效PIAS/HS隔離液。 首先通過分子結(jié)構(gòu)設(shè)計(jì),根據(jù)自由基聚合原理,以衣康酸、丙烯酰胺、對(duì)苯乙烯磺酸鈉、過硫酸鉀等原料合成了PIAS,并采用FTIR和TG對(duì)合成PIAS的結(jié)構(gòu)和熱性能進(jìn)行了表征。通過設(shè)計(jì)三因素三水平正交試驗(yàn)得到其最佳合成條件為：控制體系的pH6-7、反應(yīng)時(shí)間5hr,單體的質(zhì)量比IA:AM:SSS=1:4:3、反應(yīng)溫度55℃、引發(fā)劑加量3%。180℃×115MPa條件下,含PIAS水泥漿體的稠化實(shí)驗(yàn)和水泥石的早期抗壓強(qiáng)度測(cè)試證實(shí)PIAS對(duì)水泥漿具有良好的緩凝效果并且不會(huì)產(chǎn)生水泥漿超緩凝現(xiàn)象。通過SEM、 XRD、EDS、升降溫稠化試驗(yàn)等表征分析,探討了PIAS的緩凝機(jī)理和自適應(yīng)機(jī)理。 采用自由基接枝聚合法獲得羥乙基纖維素／對(duì)苯乙烯磺酸鈉接枝共聚物流型調(diào)節(jié)劑HS,并采用FTIR和TG對(duì)流型調(diào)節(jié)劑HS的結(jié)構(gòu)和熱性能進(jìn)行了表征。通過控制變量的方法分別設(shè)計(jì)了質(zhì)量比、引發(fā)劑加量及反應(yīng)溫度三組單因素變量合成實(shí)驗(yàn),并以所得流型調(diào)節(jié)劑HS的粘度為評(píng)價(jià)指標(biāo),從而得到流型調(diào)節(jié)劑HS的最佳合成條件,即：質(zhì)量比HEC:SSS=1:2;過硫酸銨引發(fā)劑加量0.5%；反應(yīng)溫度50℃；反應(yīng)時(shí)間8hr。 對(duì)隔離液其他添加劑進(jìn)行復(fù)配、優(yōu)選后,配置成耐高溫的高效PIAS/HS隔離液,并依照標(biāo)準(zhǔn)SY/T5374-2000測(cè)定了PIAS/HS隔離液的懸浮穩(wěn)定性、流變性以及與水泥漿、鉆井液的相容性等工程性能。實(shí)驗(yàn)表明,該隔離液在60-180℃內(nèi)能保證漿體良好的懸浮穩(wěn)定性,密度在1.2-2.4g/cm3范圍內(nèi)可調(diào)節(jié),并且能有效隔離鉆井液和水泥漿,明顯改善水泥漿-隔離液兩相混漿體系以及水泥漿-隔離液-鉆井液三相混漿體系的流變性,防止了混漿絮凝、閃凝等現(xiàn)象的產(chǎn)生。此外,通過XRD等分析手段解釋了隔離液的懸浮機(jī)理、對(duì)固井二界面的沖刷機(jī)理及其抗污染機(jī)理。
[Abstract]:Cementing is a very important process in cementing engineering. In order to avoid contact pollution of drilling fluid and cement slurry, the isolating fluid is usually injected into the well section before cement slurry. A separation is formed between the drilling fluid and the cement slurry. However, most of the existing isolated liquids have poor temperature tolerance, incompatible with cement slurry and drilling fluid, and the study of anti-pollution mechanism is not mature. Therefore, based on the synthesis of PIAS, flow regime regulator HS and other additives, a high-temperature and high-efficiency PIAS/HS isolating solution was developed. Firstly, PIAS, was synthesized from itaconic acid, acrylamide, sodium styrene sulfonate and potassium persulfate by molecular structure design, according to the principle of free radical polymerization. The structure and thermal properties of synthesized PIAS were characterized by FTIR and TG. By designing three factors and three levels orthogonal test, the optimum synthesis conditions were obtained as follows: the reaction time of pH6-7, was controlled at 5hrs, the mass ratio of monomer to IA:AM:SSS=1:4:3, was 55 鈩，

本文編號(hào)：2253043