Characteristics and Application Prospects of Diutan Gum Fracturing Fluid
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摘要: 储层改造“工厂化”体积压裂和连续混配施工,要求压裂液对配液水质有更好的广谱性和更快的分散起黏速度。本文报道了一种表面改性定优胶,可直接使用地层水、海水和回注水配制非交联型压裂液。按照SY/T 5107—2016《水基压裂液性能评价方法》对改性定优胶和压裂液进行评价,实验结果表明:改性定优胶在地层水、海水、回注水和pH值2~12水溶液中,分散性好,增黏速度快,5~20 min可达到最大黏度,满足连续混配施工要求;0.4%定优胶压裂液耐温,耐剪切性能好、网络结构弹性模量高、悬砂性能优异、能满足140 ℃压裂施工要求;0.4%定优胶压裂液破胶容易,残渣212 mg/L,比行业标准600 mg/L指标低很多,对储层的伤害小。通过定优胶压裂液前景分析,认为使用地层水,海水和回注水配制定优胶压裂液能实现压裂用水就地取材,降低用水成本和备水周期;定优胶压裂液更适合碱敏性储层和非常规致密储层的“工厂化”体积压裂和连续混配施工要求。Abstract: The factory-like volume fracturing and continuous mixing for reservoir stimulation require the fracturing fluid to have better broad-spectrum performance and faster dispersion and sticking speed in terms of water quality. This article reports a surface modified diutan gum that can be directly used to prepare non-crosslinked fracturing fluids using formation water, seawater, and reinjection water. According to SY/T 5107—2016 《Evaluation Method for Performance of Water Based Fracturing Fluids》, the diutan gum and non-crosslinked diutan gum fracturing fluid was evaluated. The experimental results showed that it has good dispersibility, fast viscosity increase speed, and can reach maximum viscosity in 5~20 minutes in formation water, seawater, reinjection water, and pH 2~12 aqueous solutions, meeting the requirements of continuous mixing; 0.4% diutan gum fracturing fluid has good temperature resistance, shear resistance, high elastic modulus of network structure, excellent suspended sand performance, and can meet the requirements of 140 ℃ fracturing operation; The 0.4% diutan gum fracturing fluid is easy to break, with a residue of 212 mg/L, which is much lower than the industry standard of 600 mg/L and has less damage to the reservoir. Through the analysis of the prospects of using diutan gum fracturing fluid, it is believed that the use of formation water, seawater, and reinjection water to develop diutan gum fracturing fluid can achieve local water use for fracturing, reduce water costs and water preparation cycles; Diutan gum fracturing fluid is more suitable for the factory-like volume fracturing and continuous mixing requirements of alkali sensitive reservoirs and unconventional dense reservoirs.
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Key words:
- Diutan gum /
- Non-crosslinking fracturing fluid /
- Salt resistance /
- Sand-carrying
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表 1 实验用水水质分析结果
mg/L 水型 Ca2+ Mg2+ Na+/K+ 总矿化度 自来水 22 6 52 260 地层水 76 12 812 2642 回注水 460 160 3652 28 615 海水 360 1256 5122 32 400 表 2 定优胶压裂液和胍胶冻胶滤失性能对比
配方 T/
℃初滤失量/
m3·m−2滤失速率/
m·min−1滤失系数/
m ·min−0.50.3%定优胶 60 5.82×10−3 1.92×10−4 3.45×10−3 0.4%定优胶 100 6.64×10−3 6.84×10−5 7.83×10−4 0.4%HPG+0.4%
OBC-2+0.2%BC-290 5.24×10−3 3.46×10−4 1.92×10−3 表 3 不同时间定优胶和胍尔胶压裂液的破乳率 (%)
配 方 t/min 3 5 10 15 30 60 120 0.4%定优胶 6 14 30 64 88 92 96 0.4%定优胶+0.3%JK12 12 26 73 89 94 100 0.4%HPG+0.3%JK12 10 23 72 87 92 100 -
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