Carbonated water (CW) and low salinity (LS) injection processes are among the most widely investigated method during the past decade due to their unique advantages. Although the results revealed rather efficiency of these two methods, it is reported that using the combination of these two methods can introduce new insight about the smart and newly developed enhance oil recovery processes. Respect to these facts, the current work is aimed to investigate the swelling behavior of heavy crude oil in carbonated water at the presence of Na₂SO₄ and Mg₂SO₄. In this way, one of the main effective mechanisms through the carbonated water injection which is swelling factor is examined in the presence of two different salts, namely, Na₂SO₄ and Mg₂SO₄, under different pressures (500–4000 psi) and temperatures (30–80 °C). The results obtained in this investigation are compared with the previously reported results regarding the carbonated brine (CB) solutions consisted of different salts such as KCl, NaCl, CaCl₂, and MgCl₂ with the same concentration of 15,000 ppm. The results not only reveal the possible mechanism behind the swelling factor variation, but also reveal that crude oil and ion type as well as temperature besides the solubility of CO₂ in aqueous phase can introduce tremendous influence on the mobility of CO₂ molecules and their partitioning from aqueous phase towards the oil phase. Also, the obtained results reveal that the presence of divalent ions can directly affect the crossover pressure toward lower values.

中文翻译：

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Na 2 SO 4和Mg 2 SO 4存在下重质原油在碳酸水中的溶胀行为

碳酸水（CW）和低盐度（LS）注入方法由于其独特的优势而成为过去十年中研究最广泛的方法。尽管结果表明这两种方法的效率相当高，但据报道，这两种方法的组合使用可以引入有关智能和新开发的强化采油工艺的新见解。考虑到这些事实，当前的工作旨在研究在Na ₂ SO ₄和Mg ₂ SO ₄存在下重质原油在碳酸水中的溶胀行为。以此方式，在存在两种不同的盐即Na的情况下，研究了通过碳酸水注入的主要有效机理之一，它是溶胀因子。₂ SO ₄和Mg ₂ SO ₄，在不同的压力（500–4000 psi）和温度（30–80°C）下。将本研究中获得的结果与先前报道的有关碳酸盐水（CB）溶液的结果进行比较，该溶液由浓度为15,000 ppm的不同盐（例如KCl，NaCl，CaCl ₂和MgCl _2）组成。结果不仅揭示了溶胀因子变化背后的可能机理，而且还揭示了原油和离子类型以及温度，除了CO ₂在水相中的溶解度之外，还可能对CO ₂的迁移率产生巨大影响。分子及其从水相向油相的分配。同样，获得的结果表明，二价离子的存在可以直接影响越低的交叉压力。