Discussion Of Some Improvement In Reforming Section Of 18·30 Project Of Making Fertilizer From COG

In our country,coal still plays a leading role in the energy-resource structure,one of the important functions of which is to provide coke for the steel industry.As a by-product of the coke-making process,coke oven gas(COG)has not been utilized effectively and efficiently,resulting in a waste of energy and pollution of environment.Therefore,a series of chemical engineering projects,which using COG as a material to produce down-stream chemical products,comes into being.In this paper,18·30 project of making fertilizer from COG,which belongs to a coal chemical enterprise attached to the author's affiliation,is taken as the object of study.Considering problems which arise in the pre-production trial,this paper conducts a study and discussion of improvements to the reforming section-a bottle neck which constraints the enhancement of capacity.Here,the technique of Computational Fluid Dynamics(CFD)is applied to the numerical simulation and analysis of the fluid field of the combustion zone in the reformer,from modeling,meshing to the options of Standard k-s turbulence model and Eddy-Dissipation Model for the following numerical calculations.According to the results of numerical simulation,and compared with other plants of the same type,it is concluded that the basic problem with the reforming section of Lingshi 18·30 project is that the fluid field around the outlet of the metallic nozzle doesn't match the combustion zone of the reformer.To fix this problem,the most cost-effective way is to modify the nozzle.During the period of pre-production trial,the modification of the reforming section has been carried out twice.Based on the designed operation parameters,respective simulations and analyses of combustion zone of the reformer made according to the design and after two times of modification are done in this paper.Combined with production practice,it is found out that the reformer after the second time of modification can satisfy the requirement for the system to operate normally and stably at full capacity.Then assuming several processing amounts of COG beyond the designed one,the author takes the reformer after the second time of modification as the object of study,and makes simulation calculations in order to initially determine whether the reformer can fulfill the condition that the processing amount of COG exceeds the designed value in a degree.In the end,according to the author's personal experience during the process of writing this thesis and some opinions from the project engineers,several suggestions are proposed in both theoretical and practical aspects.