The Key Technology Parameters Optimization Of Feed Ordinary Grinding System And Fine Grinding System

As the important developing direction of Chinese feed industry in change production style, energy saving is getting more and more attention. As one of the largest energy consumption center of feed processing systems, energy saving of grinding system is imperative. One aim of this project is to obtain optimum operating parameters and economic indicators and energy saving effects through the operation parameter optimization of typical fine grinding hammer mills; Another goal is to get the system parameters of ordinary, fine and ultrafine grinding systems through on-site measurements, to analyze the rationality and common problems, in order to provide theoretical guidance for the upgrading of these systems and energy saving. The main experiments and conclusions are as follows:Experiment 1: Two SWFP65×125 type(200 kW) fine grinding hammer mill were selected for the study, take the hammer thickness(6 mm, 5 mm, 4 mm), air volume(throttle opening degree), the pore diameter of screen slice(forward and reverse when using a combination of different pore size screens) as the study variables, take grinding mill productivity, unit power consumption, hammer wear for the assessment indicators, the experiment was carried out to optimize the operating parameters of the hammer mill. The results showed that: Hammer mill productivity continues to increase with suction air volume increased from 0 to optimum air volume, and power consumption per ton of material continued to reduced; 5 mm thick hammer get the lowest power consumption per tons of material; To set the small pore screen first facing hammer striking has better grinding efficiency than set the larger pore size screen first when use combination screen slices. The optimum combination of parameters for the device: hammer thickness 5mm, air door opening degree of 67%, with the 0.8mm pore size screen first facing the hammer striking.Experiment 2: Two SWFP65×100C type(160 kW) fine grinding hammer mill were selected for the study, take the air volume(throttle opening degree) of grinding system as the study variables, take hammer mill productivity, unit power consumption and other indicators for the assessment item, the trial was carried out to find out the optimum air volume. The results show that: For 1 # grinder with a 4 mm pore diameter of screen, 5 mm thick hammer, when crushed carp feed, grass carp feed, the optimal throttle opening degree is 66%; For 4 # grinder with a 3 mm pore diameter of screen slice, 5 mm thick hammer, when crushed corn or soybean, the optimal throttle opening is 66%.Experiment 3: The ventilation systems of ordinary grinding, fine grinding and ultra fine grinding systems in 10 production lines of six feed mills in Jiangsu and Guangzhou were tested. And their characteristics and problems were analyzed according to the test results including the air speed, air volume, air pressure, the particle size of crushed materials, pulse dust particle size of the automatic clean bag filter, pipe size and surge bin size etc. The results showed that: For the ordinary or finely grinding mill, the suction resistance at full load is at least 1000 Pa higher than idle state. dust ventilation ducts of some grinding systems are too long, some the pipelines routes are unreasonable; The fan configuration of some grinding system are not match with the system’s requirement for the air pressure, air volume; Some ordinary and finely grinding system grind material too fine, cause over processing; Smaller surge bin below the grinder, wrong type of cyclone, cause too much material inhaled into bag dust collector; Lack of accurate and effective monitoring for the ventilation parameters. These problems should be improved in the future design of grinding systems.