无机盐存在下微波辐射超稠原油脱水研究

The dehydration of high-viscosity crude oil by microwave irradiation in the presence of inorganic salt

由于超稠油粘度高、密度大,胶质、沥青质含量高,油水界面膜强度大,常规化学沉降脱水法以及电化学脱水法难以达到理想的脱水效果。采用添加无机盐的微波辐射法脱水,脱水效果大大提高。微波辐射3 m in,系统压强0.1 MPa,辐射功率225 W,静置沉降1 m in,研究了氯化钠、碘化钠、醋酸钠、硝酸钠、碳酸钠、硫酸钠6种钠盐以及氯化钠、氯化钾、氯化钙、氯化钡、氯化镁、氯化铝6种氯化物对微波辐射超稠原油脱水率以及对脱出水的透光率的影响,简要分析了无机盐作用下W/O型乳状液吸收微波的机理。结果表明,极少量的无机盐能大大提高原油的微波破乳效果,尤其是在醋酸钠的存在下,脱水率达到了99.43%。阳离子对微波破乳的影响与阳离子的极化力有关,阴离子对微波破乳的影响与阴离子半径大小有关。

The dehydration of high - viscosity crude oil is difficult by conventional chemical precipitation method and electrochemistry method because of its high viscosity, density, colloid and pitch contents and strength of interface film of oil/ water. By microwave irradiation in the presence of inorganic salt, the efficiency of dehydration can be improved a lot. Under the conditions of 3 min microwave irradiation, 1 min settling,0.1 MPa pressure and 225 W power,the influence of six sodium salts（ NaCl,NaI, CH3COONa, NaNO3 , Na2CO3 and Na2SO4 ） and six chlorides （ NaCl, KCl, CaCl2, BaCl2, MgCl2 and A1Cl3 ） on the dehydration rate and light - transmittance rate of crude oil is studied. And the mechanism of the W/O type emulsion absorbing microwave energy in the presence of inorganic salt is briefly analysed. The results show that the demulsification efficiency of crude oil can be improved greatly due to the contribution of a few amount of inorganic salt. Especially,in the existing of CH3 COONa, the dehydration rate can reach 99.43 %. The demulsification effeciency is attributed to the polarizability of the cations and the radius of the anions.