Study On Slurry Ability And Gasification Of Salinity Wastewater, Oily Sludge And Petroleum Coke In Refinery

The refinery of the poor and heavy quality of crude oil has lead to considerable by-products of high-sulfur petroleum coke,wastewater and oily sludge,which is very difficult for refinrey to disposal.Meanwhile,with the environmental policies are getting more strict,the contradiction between resource shortage and environmental constraint has increasing dramatically.Gasification of high carbon containing resources to useful syngas is an advanced technology for refinery to utilize sludge,wastewater and high-sufer petroleum coke more directly.In this paper,refinery residual activated sludge,electric desalting wastewater and petroleum coke were selected to conduct experiments of co-slurry forming ability and combustion performance,and gasification of coke-sludge-wastewater-slurry was simulated by Aspen Plus,which lays a solid foundation for recycling oily sludge and salinity wastewater and utilizing petroleum coke effeciently.Electric desalting wastewater contains large amounts of chloride ions which will causing serious corrosion to equipment,including pipeline and gasifier,also restrict the normal operation of the gasification technology.Experiments shows A600 resin have a better effect on dechlorination than others,best operation condition for A600 is: flow rate of 2 bv/h,diameter ratio 1:7,pH of 5 ~ 9;Regeneration condition is: 4% NaOH as the regenerant,flow rate of 2 bv/h;After 10 times test of adsorption-regeneration cycle,A600 resin performance is stable,and has good repeated use performance.The co-slurry forming ability of refinery residual activated sludge,electro-desalting wastewater and petroleum coke was investigated.The result showed that when the slurry only prepared by petroleum coke,the apparent viscosity of coke-slurry was raised with the increase of mass concentration.In addition,the coke-slurry is a non-newtonian fluid with yield stress and thixotropy,so the apparent viscosity of coke-slurry was raised at first and then dropped with the increase of shear rate.electric desalting wastewater replacing fresh water had little effect on slurry ability of petroleum coke,the oily sludge,electric desalting wastewater and petroleum coke could lead to co-slurry,and the coke-sludge-wastewater-slurry could be well satisfied wih the particle size distribution and cumulative efficiency of technical requirements;The apparent viscosity of coke-sludge-wastewater-slurry show an upward trend with the increase of sludge addition,he stability was improved,while mobility was decreased;the viscosity of coke-sludge-wastewater-slurry was declined when temperature increased,and the viscosity of coke-sludge-wastewater-slurry was decreased at first and then increased with the increase of pH value,optimum pH was 9.Three different anionic dispersants were selected to prepare slurry,effects of different dispersants on coke-sludge-wastewater-slurry were analyzed.The results showed that the coke-sludge-wastewater-slurry had the property of shear-thining with LS;when use NC to prepare slurry,the coke-sludge-wastewater-slurry sheared thickening firstly then sheared thinning with small amount of sludge,and it had the property of shear-thining with more sludge;the coke-sludge-wastewater-slurry sheared thickening firstly then sheared thinning with PSA,and it sheared thinning with dispersants compounded of LS,NC and PSA;the order of co-slurry ability was: PSA>NC>LS,and it's optimal to prepare slurry by dispersants compounded of LS,NC and PSA;The oily sludge could be consumed though slurry technology with electric desalting wastewater and petroleum coke,and the emission amount of salinity wastewater could be reduced significantly in the typical refinery.The combustion characteristics of coke-sludge-wastewater-slurry results showed that the TG-DTG-DTA curve of coke-sludge-wastewater-slurry only appeared one peak,at the beginning,the temperature of the sample was increased attribute to the absorbed heat,after reaching the ignition point the sample burned intensively,which released a large amount of heat,so the DTA curve rised rapidly,while the TG curve dropped dramatically;there's certain amount of alkali metal ions in electric desalting wastewater,which had catalytic effects on petroleum coke combustion;the increase of contact area between air and petroleum cokewhich contributes to a better combustion performance of petroleum coke.According to the GE gasification process,chemical process simulation software was used to establish the simulation process,Studied the influence of different operating parameters on the gas product distribution,As can be seen from the data,if improve the concentration of coke-sludge-wastewater-slurry,the amount of CO in the syngas will went up,accordingly,the effective gas(CO+H2)and gasification temperature will also rised;improving the ratio of oxygen and carbon could enhance the intensity of petroleum coke gasification reactions,but the effective gas content in syngas decreased,so the ratio of oxygen and carbon should be controlled at reasonable limits during gasification operation process;Increasing the gasification pressure and operation temperature were conducted for petroleum coke gasification reaction.