Determining efficiency of removal of dispersed phase from gases and modernization of scrubbers using high-performance packings

A solution to the problem of modeling the removal of a finely dispersed phase from stack gases and process gases at power engineering and petrochemical enterprises using a column apparatus filled with new highly efficient random and structured packings is considered. The use of diffusion and cell models of the flow structure for calculating a concentration profile of particles settling on a liquid fi lm in apparatuses filled with various packings is shown. Accounting for the deposition of finely dispersed particles from gases on the interfacial surface of the liquid fi lm flowing down along the packing is carried out using a bulk source of mass. The model of turbulent-inertial sedimentation of particles is adopted. The main parameters of the model are the coefficient of turbulent migration of particles to the fi lm surface on contact devices, a modified Peclet number with a backmixing coefficient, and the number of complete mixing cells. This approach can be generalized to a wide class of fi lm-type apparatuses for wet gas cleaning with the aim of designing them or choosing modernization options. Expressions are obtained for calculating the efficiency of aerosol separation on packings as well as the required depth of the packed bed for a given efficiency. Results of calculating the efficiency of gas purification from aerosols with the use of various types of packings in scrubbers as well as the required depth of the packed bed for a given efficiency are presented. A graphical dependence of the power spent on gas cleaning in apparatuses with different packings is given. Results of solving the production problem of cleaning pyrogas from coke and tar by circulating water in a modernized scrubber with new highperformance packings are shown. Expressions for calculating the rate of turbulent particle migration for random and structured packings as well as modified Peclet numbers are presented. A distinctive feature of these expressions is the calculation based on the known hydraulic resistance of contact devices.