الفهرس 
General information on seed cleaningOnly 14 pages are availabe for public view
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Abstract
AH cssclitiul l’cature in the Jcvclop~ucrllo l’ lllc agricullu~~:cll lqs ol’ ally country is a carefully planned seed program, by cleaning and protection of good quality secd. Separation and cleaning process are one of’the most important topics ol’ post harvesting mechanization. Grain cleaning is a basic procedure in a grain grading system in whch impurities or contaminants are separated from SOLIIICg~r ai~is. Clean grain reduces problems that occur during storage and handling. Clean grain also save storage space and increases marketability. There are many different methods of separation such as pneumatic cleaning system. Separation of a mixture of particles by fluidization in inclined air stream is possible when the aerodynamic characteristics of the particles are so different that the light particles are entrained in the air stream and the heavy particles fall through it. The obiectives of the resent study are: 1) Manufacture a laboratory unit for separating and cleaning wheat grains by fluidization. Thc suitable dinicnsions of the unit were selected and equipped with controlling tools to control air stream velocity, specific feeding rate and slope of’ separating duct downward. 2) A study of some physical and aerodynamic properties of threshing wheat materials obtained from a locally made thresher. 3) A study of the following factors which are known to affect the performance of the lluidization separating machine: a) Air stream velocity (four levels ranged from 4.1 1 to 7.95 m/s). b) Specific feeding rate (four levels ranged from 20 to 50 kghcm). c) Proportion of total impurities (four levels ranged from 8 to 16% from the total weight of tested samples). d) Slope of separating duct downward [two angles of 0.2617 and 0.5236 rad (1 5” and 30•‹)]. 4) To specify the optimum conditions of operation which ensure the highest dcgree of’cleanliness with minimum grain losses. 5) ’1’0 estimate the energy required for separating and cleaning processes at diilkrcnt air llow rates.