Research On The Industrialized Technology For Heavy Alkylbenzene Sulfonates

With the continued exploitation, now the Zhongbei oilfield has entered the stageof tertiary oil recovery. The ASP flooding system composed of alkali, surfactant andpolymer has become the dominant technology in Zhongbeioilfield due to its stablequality and improved performance in oil recovery over the traditional polymerflooding, After three years’ researches, we proposed the new research direction to usethe relatively homogeneous composition of heavy alkylbenzene as a new surfactantwith improved performance.In this thesis, we discussed various aspects in the industrialized technology ofheavy alkyl benzene sulfonate surfactant, including its flooding principle，SO3sulfonation and sulfonation reactor，the key problems in the industrialized production，group compositions of heavy alkyl benzene and their sulfonation sensitivity，investigation on preventing or mitigating the coke of sulfonation reactor，effect of thecompositions of the raw material on performances and applications of the product.Based on the experimental results, we draw the following conclusions:1. Sulfonation reaction is a complex process accompanied by heat and mass transfer,the reaction was affected significantly by temperature and SO3gas concentrationduring the reaction process. The main product was heavy alkyl benzene sulfonic acidand the by-products were sulfone and acid anhydride. The reaction was accompaniedby sulfonation, de-alkylation and the gasification reaction.2. In the industrialized production process, the temperature of sulfonation reaction device, molar ratio of SO3and heavy alkyl benzene, SO3gas concentration and otherparameters should be controlled carefully.3. Different group compositions in the heavy alkyl benzene showed differentsulfonation sensitivity. The high to low regular succession of sulfonation sensitivity ofthe main components is in the order of alkyl sulfonated naphthalene, diphenylmethane, single alkylbenzene and benzene with two alkyl substituents.4. Some group compositions of the heavy alkyl benzene were readily to be sulfonatedand some of them were difficult to be sulfonated, thus resulting in the inevitable cokein the sulfonation device. Careful control over the sulfonation temperature, the molarratio of SO3and heavy alkyl benzene, SO3gas concentration, the decreased times ofraw materials switching is benefit to delay the coke in the sulfonation device.Currently, the injection EOR used in the oilfiled is the mixture of heavy alkylbenzene sulfonate surfactant and the concentrated NaOH solution. However, thisinjection method not only blocked the reservoir porosity and thus damaged thereservoir but also promoted degradation of the polymer and deteriorated thethickening effect of the system, which limited the practical applications of the heavyalkyl benzene sulfonate surfactant.The ASP flooding is important to sustainable production of40million ton oil inZhongbei Oilfield. This work provides theoretical bases to promote the industrializedproduction of the heavy alkyl benzene sulfonate surfactant and support the sustainabledevelopment of ZhongbeiOilfield.