Oily Sludge Drying And Pyrolysis Integration Technology And Equipment

A large amount of oily solid waste,namely oily sludge,is generated during the production of petrochemical products.Oily sludge is rich in petroleum hydrocarbons and contains a large number of toxic and harmful substances,which has caused great damage to the ecological environment.It has been included in the "National Hazardous Waste List".As the country pays more and more attention to environmental protection,environmental protection regulations clearly stipulate the harmless treatment of oily sludge.This subject takes oily sludge as the research object,with the ultimate goal of reducing,recycling,and harmless oily sludge,develops a new type of pyrolysis furnace based on high-efficiency heat transfer,and designs and builds oily sludge drying and pyrolysis integration processing system.Firstly,a pyrolysis test was conducted on a small amount of small-scale oily sludge.The temperature range was selected to rapidly pyrolyze the sludge under different treatment parameters.Based on the characteristics of the pyrolysis ash residue,the pyrolysis process and system energy balance were studied.The research found that:(1)The pyrolysis temperature has a major influence on reducing the petroleum hydrocarbon content of the ash residue,and the pyrolysis time has a relatively large influence on the weight reduction rate and calorific value of the ash residue;(2)Heating the water in the evaporated sludge consumes most of the energy required for pyrolysis.In the future,most of the water in the oily sludge can be dried and then pyrolyzed to reduce processing costs;(3)When the temperature reaches 550 ?,the petroleum hydrocarbon content of the pyrolysis residue drops below 0.3%,Hazardous waste has become solid waste,which can meet the relevant requirements in the "Control Standards for Pollutants in Agricultural Sludge"and "Summary of Oily Sludge in Oil and Gas Fields.Based on various factors,the pyrolysis furnace pyrolysis working temperature is selected as 550?.Secondly,according to the conclusions of the experiment and referring to the design of predecessors,the integrated process flow chart of oily sludge drying and pyrolysis was constructed.The designed processing capacity of the system is 200kg/h.Developed a new type of pyrolysis furnace based on highefficiency heat transfer,designed and build a sludge treatment system with the pyrolysis furnace as the core,and performed material accounting and selected auxiliary equipment and pipelines.Aiming at the new pyrolysis furnace designed above,the discrete element method was used to analyze the movement and distribution of sludge particles of different plates at different speeds,and the research found:(1)The particles move at variable speeds on the surface of the plate,and the trajectory is similar to a spiral.The angle of the spiral generated by the movement of the particle on the small plate is smaller than the angle of the spiral generated on the large plate;(2)The moving speed,distance,and number of particles on the small plate are greater than those of the large plate.The residual particles of the small plate are distributed along the direction of the rake leaves,and the residual particles of the large plate will form a number of rings with different thicknesses;(3)The more the number of residual particles is closer to the center of rotation,and a small part of the particles randomly scattered on the plate,the number of residual particles on the plate decreases as the speed of the rake blade increases.According to the accumulation of particle residues,suggestions for improving the arrangement of harrow blades are put forward,The residual particles on the large and small plates were reduced by 82.1% and 53.7% respectively.Finally,the start-up test of the oily sludge treatment system was carried out.The temperature of the pyrolysis chamber of the pyrolysis furnace can reach the required temperature for pyrolysis.The test shows that the system can better treat oily sludge.The residue produced by pyrolysis at 400? has a petroleum hydrocarbon content.It is 0.78%,higher than 0.3% but lower than2%.After pyrolysis at 550?,the residual petroleum hydrocarbon content is lower than 0.3%,which is a general solid waste.Finally,the problems and economics of the operation of the system are discussed.The operating income of the system is higher than the cost,and the profit rate is as high as 188.83%.The sludge treatment program proposed in this paper has higher practical value and promotion value.