Application Of Solid Catalyst In Downhole Upgrading Of Heavy Oil

Heavy oil is an important energy source with a wide distribution and abundant reserves.Enhancing oil recovery is the most fundamental goal in developing heavy oil.But the composition of heavy oil is complex,which including various high molecular hydrocarbons and high content of heterocyclic ring,resulting in complicated post-treatment process and high cost.The purpose of this paper is to study heavy oil in situ upgrading under the condition of fire flooding,including low temperature oxidation and high temperature oxidation.The heavy oil in situ upgrading technology can remove heteroatoms and heavy components.So that the produced heavy oil will have higher quality,and a gentler and easier treatment process can be used in the ground.In this paper,the transition metal/ZSM-5 catalyst was synthesized by the incipient wetness impregnation method,and its characterization test was carried out.The oxidation law of the heavy oil in the low temperature oxidation condition was studied,and the soild catalaysts with accelerating oxidation effect were optimized.The oxidation law of the heavy oil in the high temperature oxidation condition was studied,and the soild catalaysts with certain cracking and viscosity reduction effects were optimized.Details are shown below:(1)The transition metal/ZSM-5 solid catalyst was prepared by the incipient wetness impregnation method.The catalysts were characterized by XRD,SEM and other techniques.The results show that after the solidification of the transition metal on the ZSM-5 support,the characteristics of Ni-Mo metal appear on the SEM and XRD spectra.(2)The law of low temperature oxidation of heavy oil was studied by using ZCF-reactor.Nano-nickel oxide powder was selected as the optimum catalyst for low temperature oxidation of heavy oil.The optimal reaction condition of nano-nickel oxide powder catalyst was determined to be 12h and 0.5wt%catalyst addition.(3)A new type of heavy oil high temperature and high pressure micro-expressions device was designed,which can achieve the real-time injection of heavy oil or other reactants,temperature resistance of 600? and pressure resistance of 15 MPa.Using this reactor,the high temperature reaction of heavy oil can be studied.It was found that under high temperature oxidation conditions,high temperature thermal cracking of heavy oil is the dominant reaction,while catalytic oxygenation reaction is secondary reaction.Relative to the blank test group,Ni-Mo/ZSM-5 test group can obtain 50.74%viscosity reduction rate.Ni-Mo/ZSM-5 catalyst has outstanding effect in the breaking of C-S bond in heavy oil;CH4 in oxidation gas is beneficial to the improvement of stability parameter of heavy oil.After adding of NiMo/ZSM-5 catalyst,the stability parameters of the heavy oil are improved;the reaction basically reaches equilibrium in 20 minutes.(4)The upgrading of heavy oil in combustion in situ was discussed,and this process was divided into two parts:low-temperature oxidation reaction and high-temperature oxidation reaction.The oxidation reaction of heavy oil at low temperature is dominated by oxygenation.The oxidation reaction of heavy oil at high temperature is dominated by high temperature thermal cracking of heavy oil.