Engineering Case Study On Industrial Continuous Organic Wastes Pyrolysis Technology

As a huge number of organic wastes accumulate in social life,due to their high stability,difficult to decompose,and flammable characteristics,the piling up of organic wastes will occupy a large amount of land resources,and cause organic matter volatilization,disease transmission,river pollution,and even fires disaster etc.,which brought serious environmental pollution to the air,soil,organisms and water systems and serious safety hazard to the environment on which mankind depends.Therefore,there is an urgent demand to develop a feasible and advanced treatment method.Pyrolysis is a hot technology that is widely studied nowadays.Because of environment friendly,it has been vigorously researched and promoted in recent years.This paper takes the treatment of waste tires as an example.First,experimental unit is used to investigate the influence of factors such as pyrolysis temperature,material particle size and special catalysts on the pyrolysis of waste tires,in order to obtain the best process conditions.Second,the process conditions are proved through a single set of industrial continuous pyrolysis unit,continuously feeding and discharging,with constant improvement on equipment and process,and it also analyze the engineering costs and environmental protection.（1）The oil separating and cooling system adopts the cooling form of vertical structure,designed with the process of spraying backflow,avoiding the problem that the heavy components in the gas phase mix with the fine particles accumulated on the pipe wall causing the pipeline blockage,and solving the potential safety hazards and environmental pollution problems caused by frequent shutdown and cleaning of gas pipelines.（2）The gas purification section adopts the wet alkali absorption method,which avoids the potential safety hazards of spontaneous combustion due to excessive local temperature in the iron oxide method.With the increasingly strict environmental protection trend,the mature SCR de-nitration technology is combined with this set of flue gas emission process to simplify the urea solution decomposition equipment.The two processes have been verified by the actual operation on the site and obtained the good operating results.（3）As the results of analysis on pyrolysis process cost and carbon emission indicate,The direct operating cost of the complete pyrolysis equipment is about 1104 CNY/ton of tires,and the direct profit is about 2010 CNY/t,gross profit about 906 CNY/t.It shows that this set of equipment has the characteristics of low operating cost and high profit in the treatment of waste tires.The total CO₂ emissions generated by the treatment of 10000tons of tires are 3401.7 tons due to fuel and electricity consumption.Tire pyrolysis can maximize the recovery of high value-added resources such as pyrolysis oil,carbon black and steel wires.The pyrolysis products are used as alternative raw materials,and 10,000tons of tire pyrolysis can reduce CO₂ emissions by 10474.8 tons,which is consistent with the data found in the literature that processing each ton of tires can reduce CO₂ emissions by 1 ton.Therefore,the pyrolysis treatment on waste tires meets the requirements of environment friendly,circular economy and sustainable development advocated in China.（4）The test conditions of the optimal pyrolysis temperature,catalyst and material particle size are obtained through the experimental unit,and applied to the industrial continuous unit.After the actual operation on the site,the experimental unit and the industrial continuous unit have a trend of consistency in the pyrolysis temperature.However,the yield of pyrolysis oil in the industrial continuous unit is generally higher than that of the experimental unit.From an economic perspective,the industrial continuous unit is more suitable for the requirements of market development and has a larger market application prospect.