Studies On Process Improvement And System Optimization Of Waste Fluid In Production Of The Alkali Boiler Mixed Firing Caprolactam

Cyclohexanone device of caprolactam projects supporting the saponification waste lye burning boiler,a processing capacity of 18t/h,types of boilers is WDLZ35/1.47-1.The boiler can burn saponification waste alkali in cyclohexanone production,auxiliary fuel for X heavy oil.When burning,the heat recovery can be used for producing low pressure steam for other devices,and the recovery of sodium carbonate can reduce the environmental pollution,and the economic benefit and social benefit are good.Recovery of sodium carbonate in two ways.One is through the electric dust removal and ash recycling in the boiler exhaust the powdery solid sodium carbonate,accounts for about 50-60% of the total recovery rate,the second is the dry method recovery of the outflow from the bottom of the boiler fused sodium carbonate.Process improvement research is mainly two aspects: the first is the original x heavy oil changed to purge gas: compared with the original design,cancel x heavy oil conveying pipeline and changed it to purge gas pipeline,purge gas duct pressure 0.4~0.5MPa.About 25 degrees Celsius temperature,the need to flow 2300Nm3/h(rated),3500Nm3/h(the largest),into the furnace required following the actual deflation pressure about 30 kPa,through 10 gas nozzle respectively enter the furnace from different locations and on furnace continued to add heat.According to the pressure and the flow rate of the air vent pipe,the pipe diameter is calculated.Through the calculation shows that the relaxation of the gas mains should be controlled by DN200(flow rate control in 8m/s),after the decompression of the main pipe using DN300(flow control in 14m/s).According to the technology and safety requirements,purge gas release the pressure of the set flow display,valve before the pressure field and remote display,before the valve remote temperature show that non-return valve,rapid shut-off devices;relief valve set pressure and remote display,each branch enters the furnace pipe to install cut-off valve and the metal hose connection,setting nitrogen purge port and exhaust port.After the pressure reducing valve setting blind position in order to ensure the safety of maintenance.Second,waste alkali liquor blending of caprolactam concentrate waste: because of caprolactam wastewater has been concentrated,so you can directly through the pipeline to the waste working tank,and then through the into the furnace saponification liquid pump pressure to 2.0MPa,by alkali gun in the furnace formation of atomized liquid fuel to burn fully.Because of caprolactam wastewater composition is much more complex,may contain trace amounts of ammonium sulfate,so waste alkali liquid,furnace saponification liquid pump and a pipeline material selection to re study,due to the working fluid increases the part of caprolactam wastewater,the flash evaporation of non condensable gases increase,thus to safety to the working groove discharge and on-site environmental governance work study.Waste boiler mixed burning of caprolactam wastewater process improvement and system optimization is for waste boiler operation conditions optimization.Waste boiler previously used mainly for cyclohexanone saponification waste liquid incineration,and in the study focuses on the alkali boiler not only burned the cyclohexanone device generates the saponification waste liquid,and blended with caprolactam extraction process and the feasibility of the regeneration process of waste liquid from pay,the waste boiler combustion supporting agent by X heavy oil changed to purge gas the feasibility,and the two benefit comparative analysis,finally summarizes the scheme optimization of caprolactam production wastewater treatment.The research content of this paper is a comprehensive treatment of pollution and environmental protection projects.Research is focused on waste alkali liquid composition and combustion burning medium group can be divided into two aspects of optimization improved,through theoretical analysis,reforming experiment and operation analysis,etc.to illustrate transformation,rationality and advancement of,also on the part of the core equipment selection are analyzed and studied.Through the theory study and practice prove that the improvement is successful.It not only solves the caprolactam production wastewater difficult to deal with the problem,and the by-product steam and sodium carbonate products and the economic benefit is remarkable,also gas emissions indicators have reached the requirements of the relevant national standards.So the project has the characteristics of the development of green circulation,can be applied in the industry.