Study On Synthesis Of Petroleum Sulfonate Surfactant Used For EOR With Application Of Higee Technology

As one of the most efficient anionic surfactants in chemical flooding in the exploitation of oil fields,petroleum sulfonate (PS) exhibits obvious advantages in raw material availability, production cost, good molecular weight distribution, high interfacial activity,etc.PS is synthesized through sulfonation of petroleum fraction by sulfonating agent(SA),and it is usually liquid-liquid or gas-liquid fast reaction with strong exothermic effect. Corresponding measures must be taken in reactor design and process optimization in order to reduce the mixing time of the viscous mixture in reactors and to rapidly remove the large reaction heat when instant uniform concentration and temperature in reactors are required.Generally, reactors for sulfonation reaction are usually classified into three types:the stirred tank reactor(STR),the falling film reactor (FFR) and the jet loop reactor (JLR).However, STR is the only one successfully applied in synthesis of PS in industrial scale. It would be difficult to reduce the residence time of the reaction mixture in STR,and its heat and mass transfer efficiency is low, leading to more side-reaction and low active matter content. HIGEE, carried out in a rotating packed bed (RPB),is regarded as an advanced process intensification technology. In the high gravity environment provided by HIGEE, the efficiency of micro-mixing and inter-phase mass transfer could be greatly increased comparing with traditional reactors.Based on the understanding of fast exothermic reactions and the features of HIGEE technology, we conceive that RPB can meet the requirements for petroleum sulfonation, and it may be an ideal reactor for PS synthesis.This work explored the feasibility of synthesizing PS in RPB.The major innovative work of this paper is as follows:1.With application of HIGEE process intensification technology, PS surfactant used for EOR was synthesized from vacuum side cut 2 of Shengli crude oil by three different SA:diluted liquid sulfur trioxide, diluted gaseous sulfur trioxide and fuming sulfuric acid. For each kind of SA, the effects of various experimental conditions (such as Solvent/Oil ratio, SA/Oil ratio, gas concentration, temperature and time) on the content of active matter and unsulfonated oil were investigated. Under their optimal reaction conditions, the target product was prepared with high active matter content and extremely low level of oil/water interfacial tension.Based on a great deal of experimental practice and investigation of literatures,the two phase titration method (as core of the existing standards for PS product testing) was modified and the testing accuracy and efficiency were improved. 2.In consideration of the different phase (gas or liquid) of SA served and the features of sulfonation reaction itself, the HIGEE liquid-liquid and gas-liquid sulfonation process were designed and their respective pilot test equipments were esTablelished correspondingly. The effects of various processing parameters (such as gas/liquid ratio, rotating speed and circulation ratio) on the content of active matter and unsulfonated oil were investigated and their optimal values were recommended.PS surfactant The properties of PS surfactant synthesized by HIGEE technology were better than those of Shengli product.In accordance with the results and phenomena of HIGEE gas-liquid sulfonation process, an idea for household detergent synthesis by HIGEE technology was proposed and exploratory experimental research were put into practice.Linear alkylbenzene sulfonic acid with good qulity was obtained and the feasibility of this production process was proved.3.Design and calculation for "HIGEE process intensification technology-PS demonstration line(1000 t·a-1)" was accomplished, including determination of process,equipment type, operating parameters, etc. The construction of this production line and industrial experiment followed were completed in Yuan Ren Co.,Ltd. in Shengli oilfield,5/2009.PS surfactant product was produced with high performance.The higher product quality and higher process efficiency of HIGEE technology is proven by a comparison with traditional STR. 4.Based on the previous study on micro-mixing and liquid flows in RPB, a coalescence-dispersion model was used to describe the micro-mixing and liquid-liquid sulfonation reaction of PS synthesis in RPB.The parameters of the model were estimated according to the literature cited and the experimental results.It was found that the simulated data agreed with the experimental data commendably.