支撑剂

水力压裂技术是油田增产的一种有效技术。其工艺过程是利用地面上的高压泵组,将高粘度的压裂液以大大超过地层吸收能力的排量注入到井内,在井底憋出高压；当此压力大于井壁附近的地层应力和地层岩石抗张强度时,在井底附近的地层会产生裂缝；继续注入带有支撑剂的含砂液,裂缝向前延伸并被压裂支撑剂填充,关井后裂缝闭合在填充的支撑剂上,最后在井底附近地层内产生具有一定几何尺寸和导流能力的裂缝,便于周围原油更快流入油井底部,达到增产的目的。支撑剂作为水力压裂中的重要填充介质,其性能直接影响了整个油井的增产能力。所以,研究高性能石油支撑剂对于油田增产是非常必要的。石油压裂支撑剂*主要分天然石英砂、人造陶粒支撑剂、树脂包覆支撑剂(即覆膜支撑剂)三大类,其中覆膜支撑剂又分覆膜砂和覆膜陶粒两种。天然石英砂因其圆球度不好,强度低,但成本最低,所以一般在浅井中大量使用；人造陶粒支撑剂由于其圆球度好,强度高,耐腐蚀性能强,导流能力好等优点,般被大量用于中、深井的压裂。覆膜砂由于经过树脂包覆后强度好,密度变小,可以代替陶粒支撑剂在中等深度的油井使用,而覆膜陶粒支撑剂的研究较少,成本较高,暂时未能用于实际生产用。传统的人造陶粒支撑剂制备的方法主要是铝矾土和助熔相(如锰矿粉)按一定比例配合,经过粉碎研磨(粒度为300目),经圆盘造粒机按一步造粒法制备生料球,经过高温烧结制备出中密度或高密度陶粒支撑剂。本文通过油页岩渣、铝矾土和助熔剂按比例配合,经粉碎,利用圆盘造粒机按引子造粒法制备生料球,再经过高温烧结制备出低密度陶粒支撑剂。油页岩渣是油页岩提炼页岩油之后的废弃物。油页岩渣的累积堆积需要占用大量土地,而且会危害周围居民身体健康；其污染过程是油页岩渣中含有的大量重金属元素,经过雨水淋溶或扩散后严重污染周围的水源、土地,使土地毒化、酸化,破坏土壤生产能力,破坏农业生产,从而危害居民健康。但是油页岩渣中含有大量的矿物成分,如石英,长石,粘土成分等,经过蒸馏煅烧之后,其结构非常的疏松,具有非常轻的密度,较大的烧失量。利用油页岩渣来制备人造陶粒支撑剂和覆膜陶粒支撑剂,不但可以减少油页岩渣堆积对大量土地的占用,消除对环境、生态以及人类健康的严重威胁,还可以提高油页岩渣的利用价值。所以对油页岩渣资源化的研究有非常重要的意义。从理论上来讲,传统的陶粒支撑剂是以纯刚玉相为支撑骨架,玻璃相起粘结作用,使整个陶粒支撑剂具有了很好的强度和优良的耐腐蚀能力。在此

基础上,添加油页岩渣,可以增加陶粒支撑剂中的莫来石含量,利用莫来石相交织在一起产生的韧性,使陶粒的整体结构的强度更好,破碎率更低。另外,添加油页岩渣,当两种原料充分混匀以后,油页岩渣存在的有机质以及氧化铁成分,可以更快的将碳质成分氧化,更容易形成均匀的闭合气孔,使陶粒的体积密度和视密度更小利用油页岩渣的以上特点,制备低密度的石油压裂支撑剂和覆膜支撑剂,其创新之处有：1)首次在铝矾土中添加30%的固体废弃物——油页岩渣,制备出满足国家标准的低密度陶粒支撑剂。2)以添加50%的油页岩渣制备陶粒支撑剂作为骨料,制备出了满足国家标准的疏水亲油的覆膜支撑剂,同时,可以提高支撑剂的强度以及提高导流能力。3)首次使用ρ-Al2O3作为陶粒支撑剂的粘结剂,提高了支撑剂的性能。本论文中,首先通过对采集于黑龙江牡丹江的油页岩*进行了煅烧、磨细处理,对油页岩及油页岩渣的烧失、密度、矿物成分以及微区形貌等性质进行了分析,并在此基础上,利用经过处理的油页岩渣粉料和铝矾土粉料以及助熔相(如锰矿粉)按一定的比例配合,通过造粒,高温烧结,制备出低密度的陶粒支撑剂,系统地研究了油页岩渣的添加量,助熔相添加量,以及烧结温度和烧结时间对陶粒支撑剂抗压性能的影响,并对陶粒支撑剂的圆球度、体积密度、视密度、破碎率、导流能力、耐腐蚀能力、矿物物相与微区形貌等都进行了检测分析。针对陶粒支撑剂存在的问题,对其性能进行了改善,主要有：使用氧化铁粉来代替锰矿粉来进行烧结助熔；通过将油页岩渣进行酸洗处理,减少油页岩渣中的有害成分,如氧化钙等；通过添加各种粘结剂来提高陶粒支撑剂的性能。通过上述实验,对陶粒的原料化学成分的配比,各成分对陶粒的影响进行了分析,并就造粒的原理、烧结的原理以及陶粒晶体长大的过程也进行了研究。最后将添加了50%油页岩渣制备的陶粒支撑剂作为骨料,利用酚醛树脂和环氧树脂的混合树脂配合增塑剂、偶联剂和固化剂进行包覆,制备出性能优异的低密度高强度覆膜陶粒支撑剂。论文取得的主要研究成果如下：1.提出了一种利用油页岩渣制备石油压裂支撑剂的新配方,该方法国内外尚未见报道,也为低铝铝矾土的应用探索了一条新途径。具体配方如下：将10-30%的油页岩渣、70%～90%的铝矾土,2%～6%的锰矿粉,1%～3.5%的粘结剂ρ-Al2O3混合,制备出了满足国家标准要求的陶粒支撑剂；该陶粒支撑剂还有另一大优点：低密度,即体积密度为1.52g/cm3,视密度为2.90g/cm3,52MPa破碎率为7.56%,明显优于

普通陶粒(体积密度>1.7 g／cm3,视密度>3.15g/cm3).2.论文首次将7-Al2O3用于陶粒的生产,并对其机理做了合理的解释。这种高温粘结剂,将松散的刚玉、莫来石和玻璃相紧密联系起来；其在低温时水解,生成三水铝石和勃姆石胶体,产生粘性,增大陶粒生料球的结合强度,在高温下,其活性很强,既可与刚玉相结合,又可与二氧化硅生成莫来石,最终形成致密块体。3.首次利用酚醛树脂和环氧树脂的混合树脂(添加比例为2：1),制备出了一种低密度高强度且亲油疏水的覆膜陶粒支撑剂,其体积密度为1.38 g／cm3,视密度为2.35 g/cm3,52MPa压力下破碎率为2.16%,酸溶解度1.05%,符合国家标准。与陶粒支撑剂相比,覆膜支撑剂的强度大大增加,其破碎率降低10%-20%,支撑剂的体积密度和视密度也非常低,酸溶解度降低至1%左右。在包覆树脂之前,水透过支撑剂的时间只需要9s,色拉油透过支撑剂的时间则需要80s,；覆膜之后,水透过覆膜支撑剂的速度明显降低,透过时间达到了90s,而油通过支撑剂的时间也增长到了120s,水透过时间增长了10倍,而油透过时间增长了1.5倍左右。4.确定了支撑剂覆膜效果的最佳条件和最大影响因素。最佳实验条件是A3D2B2C1,即在100g陶粒中应添加酚醛树脂和环氧树脂比例为2：1的混合树脂添加量6g,增塑剂邻苯二甲酸酯0.5ml,偶联剂乙烯基三乙氧基硅烷0.1ml,固化剂三乙烯四胺0.4ml,润滑剂聚酯酸钙0.25g,反应温度190℃,反应总时间1h。通过方差分析得知陶粒支撑剂的主要影响因素为树脂,次要因素为固化剂、增塑剂和偶联剂的添加量。5.氧化铁粉作为助熔剂助熔效果低于锰矿粉,但可以促进莫来石相的生成。6.油页岩渣制备陶粒支撑的原料和助熔相得要求如下：铝矾土的铝含量为70%左右,最佳助熔相比例：MnO2、Fe2O3、FeO、TiP2之和为5％；Na2P. K2O、CaO、MgO之和为1-3%。7.酸洗可以减少油页岩渣中的氧化钙的含量,降低了陶粒中长石相的存在,进而提高了陶粒的性能。其中酸洗所用酸的最佳体积浓度是20%。 更多还原

【Abstract】 The hydraulic fracturing technology is one kind of effective technology which contribute to improve oil production. The pressure produced by a group of high-pressure pumps is higher than that of the strata in the oil-well, it

can create additional passageways in the reservoir. The

macroviscosity-breakdown-fluid containing proppants can make the proppants pass into the passageways, so the paoppants in the fractures offere additional channels which has a certain geometry size and has a high flow conductivity, thus the production of oil well is improved. It is very important to study and improve the charateristic of the proppants in the increasing of the oil well production.It is classified the petroleum fracture proppant into 3 types:natural quartz sand, artificial ceramic proppant, resin coated proppant. And the resin coated proppant can be divided into two kinds:coated sand and coated ceramic sand. The natural quartz sand is generally used in shallow oil well because of its round sphericity is not good and the strength is low, but the cost is lowest. The artificial ceramic proppant usually used in moderate-depth oil well because its round sphericity is good, the strength is high, and it can povide a high flow conductivity and can resistant corrosion. The sand coated by resin can increased its stength and lowe the density, so the coated sand can replace the ceramic proppant to be used in the moderate-depth well. The research of resin coated ceramic proppants was few, and it is expensive, so it has not used in production now.The traditional method to the make ceramic proppant is mainly using the bauxite and flux phase (such as manganese powdered ore) according to the certain proportion, by the smashing attrition (300 mesh of granularity), pelletizing using the disc pelleter according to one-step pelleting method, finally the midium-density or high-density ceramic proppants is calcanating in high temperature.In this paper, it is used the oil-shale-dregs, the bauxite and flux phase according to certain proportionate, through smashing, pelletizing, finally the low-density ceramic proppants being calcanated in high temperature.The oil-shale-dregs is the wastes after refining the

oil shale to obtain the shale oil. The oil-shale-dregs not only need taking the massive lands to be piled up,and also include the massive heavy metal element. After passed through by the rain water, it may seriously pollute the water source and the soil, and cause the soil poisoned, acidified, low soil productivity, destruct the agricultural, finally make harms to the human being. But in the oil-shale-dregs, there are the massive mineral component, like the quartz, the feldspar, the clay ingredient and so on. After distillation calcine, its structure becomes loose, owning the very low density and much ignition loss. Using the oil-shale-dregs to prepare the ceramic proppant and the film coating ceramic proppant, not only can reduce massive land occupancy, eliminate the burden of the environment, the ecology, and the human being’s health,but also may enhance the value of oil-shale-dregs. Therefore it is of great importance to make the oil-shale-dregs change to resources.Theoretically, the traditional ceramic proppant is a pure corundum phase as the support skeleton, the glass material as cohesive part, that make the entire ceramic proppant to have the very good stength and high anti-corrosive ability. Based on this theroy, by adding the oil shale residue, it can increase the mullite content content in the ceramic proppant. It makes the proppant with high strength and lower broken percentage on high pressure by interweaves toughness produced by the mullite phase. In addition, when two raw materials mix uniform, organic matter and iron oxide contained in the oil-shale-dregs can oxidize the carbon components faster, and easily form uniform closed pores, so the bulk of ceramic density and apparent density become smallerUsing of the above advantages of the oil-shale-dregs, it is prepared the low-density oil proppant and the coated proppant, the innovations include:(1) It is for the first time prepared the low density oil ceramic proppant that is satisfied the national standards by adding

30%wt solid waste-oil-shale-dregs residue to the bauxite.(2) It is for the first time prepared the coated oil proppant which is satisfied the national standards and with pro-oil hydrophobic properties and by adding 50%wt of the oil-shale-dregs to the bauxite. The proppants have the high strength and the high flow conductivity.(3) It is for the first time usingρ-Al2O3 as the cementing agent in the ceramic proppant, which obviously enhanced the performance of the proppant.In this paper, firstly it is burnt and milled the oil shale which is from the Mudanjiang City, Heilongjiang Province, then analyzed its loss on ignition, density, mineral components and micro area morphology. And on this basis, it is prepared the low density ceramic proppant through the granulation, high-temperature sintering by the use of the mixture according to a certain percentage of oil-shale-dreg powder and bauxite powder, with a certain quantity of flux-phase (such as manganese powder). Following this, it is systematically studied the influnce of the icosahedral,the bulk density, apparent density, the broken percentage, conductivity, corrosion resistance, mineral phases and the micro-area morphology of the proppant by adding amount of oil-shale-dreges and the flux, the sintering temperature and sintering time. In connection wth the problems of the every kind of ceramic’s performance, it is studied the sintering flux by the use of iron oxide powder instead of manganese powder, the reducing of the harmful ingredients, such as calcium oxide, by acid treatment; the selection of variety of binders. Through all of the experiments, it is analyzed the influnce of the percentage the chemical composition of the ceramic materials, the impact of the composition on the ceramic, the principle of granulation, and the principle of the sintering and the growing up process of the ceramic crystals. Finally, it is prepared coated ceramic proppant with high performance, low-density by using of the aggregate which is

prepared by adding 50%wt of the oil-shale-dreges, coating by coupling agent, curing agents and epoxy resin mixed with phenolic resin and the plasticizer.The paper obtains the following main conclusions:1. It is for the first time prepared the oil proppant using the oil-shale-dregs, the raw materials being:10-30%wt of oil-shale-dregs,70-90%wt of the bauxite, adding 2%-6%wt of manganese powder, 1-3.5%wt of cementing agent. The ceramic proppant prepared is satisfied the national standards. The prescription of this paper is the wholly self-owned intellectual property rights. The anather advantage of the oil proppant is its low density:1.52g/cm3 of the bulk density,2.90g/cm of the apparent density,7.56% of the broken percentage under 52MPa, it obviously surpasses the traditional ceramic proppant(1.7g/cm3 of the bulk density, large than 3.15 g/cm3 of apparent density).2. As a high temperature cementing agent, the advantage of theρ-Al2O3 is that it may hydrolisis in the low temperature, produce three diaspores and boehmite gel, and increase the bonding strength of the ceramic crude material ball. Its activity is very high under high temperature, it may unify with the corundum, also produce the mullite, connect the crystal. It is for the first time to useρ-Al2O3 as the cementing agent in the production of the oil proppant.3. It is for the first time prepared a coated proppant by using the resin mixed with phenolics and epoxy resin (proportion being 2:1), which has low density, high strength, and with the hydrophobic and lipophilic properties. Its bulk density is 1.38g/cm3, the apparent density is 2.35g/cm3, the percentage of broken is 2.16% under 52MPa, and the acid solubility 1.05%, which is satisfied the national standards request. Compared with the ceramic proppant, the strength of the resin coated proppant increases greatly, its percentage of broken may reduce 10%-20%, and the bulk density and apparent density is also very low, the acid solubility is

reduced about 5%. Before coated, it only needs 9s when water Infiltrated,80s when the salad oil, but after coated, the penetration rate reduces obviously, it needs 90s to the water 120s to the salad oil, the time need to the water grew 10 times, but to the oil grew about 1.5 times.4. It is determined the best conditions for the oil proppant and the largest influncing fator by orthogonal experimental method. The best experimental conditions is A3D2B2C1, that is, in 100g of the oil proppant, adding 6g mixture of resin and epoxy resin by the ratio of 2:1,0.5ml of phthalate plasticizers,0.1ml

of

coupling

agent

VTES,0.4ml

of

curing

agent

triethylenetetramine and 0.25g of lubricants polyester, and the reaction temperature being 190℃, total reaction time being 1h. It is concluded from mean square deviation that the main factors is the resin, the secondary factor is the amount of additing of curing agent, plasticizer and coupling agent.5. Compared with manganese powder, the iron oxide powder as flux phase is bad, but it could promote the mullite production. When adding iron oxide to 7%wt, the bulk density is 1.58g/cm3, the apparent density is 2.93g/cm3, the broken percentage is 11.89%. Analyzed by the X-ray diffraction, by adding oxidizes iron powder, the content of mullite is higher than that of the corundum, which is revealed that the iron oxide could promote the mullite production.6.The best percentage of flux phase is 5%wt of MnO2, Fe2O3; FeO, TiO2 and 1～3%wt of Na2O, K2O, CaO, MgO.7. The calcium oxide content in oil-shale-dreges is reduced by using the acid pickling, that also reduced the content of the feldspar in ceramic proppant. The best bulk concentration of the acid is 20%. After the acid pickling experiment, when not adding cementing agent, the ceramic proppant prepared is not very good, it needs further study. 更多还原