The Study Of The State Of The Calcium In The Crude Oil And The Advanced Decalcifying Agents

In recent years, domestic crude oil is getting heavier and lower quality along with the application of the tertiary recovery technique. At the same time,calcium content in some domestic crude oil has been increasing quickly, which has a bad effect on the desalter and FCC's daily operation. The existing decalcification technique are not optimal,especially when they encounter some crude oil which has higher quantity of oil-soluble calcium.Therefore, it is necessary and urgent to select a highly efficient decalcification technique which bears good removal ability for oil-soluble calcium and to improve the processing technique for heavy oil.By applying electrical desalting process, the most suitable demulsifying agent and the optimized conditions for the Venezuela oil that have been founded. The writer used some kinds of chelating agents, such as HPAA,HPMA,PBTCA,MA/AA,ATMP, HEDP,PAPEMP,PAA,BHEDTMPA , A, that can react with calcium as decalcifying agents, and estimated their decalcification ability,and also did some theoretical analysis. The effects of dementalization are evaluated for the relatively effective decalcification combined with organic ester which can remove the Ni,V from the crude oil. This thesis also studies a polymerization process that synthesizes polyaspartic acid(PASP)by maleic anhydride and ammonia as raw materials, polysuccinimide(PSI) was synthesized by liquid polymerization, hydrolysising Polysuccinimide under alkaline conditions can obtain Pure sodium Product. then we evaluate the dementalization ability of the PASP and research the existential state of the Calcium in the crude oil. The ultimate result indicate that the main component of the decalcifying agents is HPAA, and the two other auxiliaries also have the preferable function of removing the Ni,V from the crude oil. The PASP also has a better decalcified ability and it is the most important component of the advanced and environmental decalcifying Agents. In addition, This thesis made some primary studies on the mechanism of calcium removal, using conductimetric titration. And we can get initial result that the decalcifying agent reacted with calcium in crude oil and formed an ionic water-soluble complex.