Modelling of pulverized coal conveying in pipe systems

ABSTRACTMaster ThesisMODELLING OF PULVERIZED COAL PNEUMATIC CONVEYING IN PIPE SYSTEMSCeyda TurasayInonu UniversityGraduate School of Natural and Applied SciencesDepartment of Chemical Engineering67+xi pages2006Supervisor: Y. Doç. Dr. Ayşe SarımeseliPneumatic conveying is a method of transportation of bulk products in a pipeline usinga gas stream. Application fields of pneumatic conveying increased gradually until today andpneumatic conveying have a wide range of application fields that include chemical,pharmaceutic, food, mineral processing, steel, plastic, rubber and power generation industries.The main objective of this study was to make a computer aided modelling of thetransport of pulverised coal and the bifurcators used in pipelines, such as in power generationindustry, AND to suggest a new design or a piece of equipment to be able to obtain forhomogeneous distribution of the particles between the arm of the bifurcator.In the first stage of the presented work, FLUENT and its preprocessor GAMBIT wasused. The solid model of the pipeline system was drawn in GAMBIT and was divided intomeshes. Then, it was transported to FLUENT and the boundary conditions were defined. Inthe numerical studies, the particle density range of were 1500, 700 kg/m3 and a particle sizerange of 1, 10, 30, 53, 75, 106, 150 microns. The results showed that the optimum particlesize was 30 microns and angle of feed was 90 degrees without introducing any suggestedelement to the pipeline. However, a new element was designed and obtained position ofinversor valve to be able to homogeneous distribution for each particle diameter and densityIn the second part of the present study, the experiments were performed with coalparticles that have diameters of -150+106, -106+75, -75+53, -53 microns and a density of1150 kg/m3 . Also the ash particles with same particle diameter range as the pulverised coalthat have a density of 700 kg/m3 were used.After a series of trials, a convenient piece that can be called `inversor valve? was foundsuitable for the homogeneous distribution of the powdered material in bifurcator. From theresults of both the experimental and numerical studies carried out at each particle diameterand density values, it can be clearly seen that the suggested piece, supplied a homogeneousdistribution at almost of all particle density and size ranges used in the study.Anahtar Kelimeler: Pneumatic Conveying; Computational Fluid Dynamics(CFD);Turbulence Models; Gas-Solid Systems.