The Research On The Ultrafine Particles Equipment System Of Crop Sraw

Crop straw is the general term of mature crop stems and leaves(ear) part. Usually it refers to the remaining portion of wheat, rice, corn, canola, cotton, sugar cane and other crops after harvesting the seeds. With growing economic and social development and environmental protection requirements, crop straw waste resource recycling become hotspot in the field of agricultural machinery and agricultural engineering field, the technology of comprehensive utilization of crop straw by various aspects of attention.Straw generally first need to go through grinding process before it can be biomass utilization, and then to realize the comprehensive utilization of biomass, straw fertilizer, straw energy, straw feed, straw, straw based industrial raw materials. According to the product particle size or particle size, crop straw crushing can be divided into general grinding, fine grinding, fine grinding(Superfine) 3 grades(the fineness respectively were above 5mm, 0.1~5mm, 0.05~0.1mm). At present, the domestic and foreign research on crop straw common crushing equipment are more, and little research on superfine crushing equipment. In order to dispose of a reasonable and adequate use of surplus straw resources, improve the comprehensive utilization of straw, at the same time, further solve the problem of the straw pulverizer low productivity, high energy consumption, poor adaptability, it is an urgent need to study the high performance superfine grinding technology and design the equipment.This paper includes the following contents:(1) Based on research and analysis of working principle, the advantages and disadvantages about the existing straw conventional comminution technology, domestic and foreign common crushing equipment and ultra-fine grinding equipment, straw initially identify structural form and general layout of the straw ultrafine grinding equipment.(2) Analyze and demonstrate the working principle and design scheme of the straw superfine crushing technology. Through the analysis of the cutting property of straw, straw and straw cutting process of cutting force, and determine the knife cutting speed, pushing angle and slide cutaway, calculated at the maximum cutting straw knife cutting force. Based on coMParative analysis of the feed material way, the knife tooth profile shape, guillotine cutting mode, the crushing chamber structure, hammer arrangement, the feeding method, determine the analysis objects, and further improve the structure of ultra-fine grinding equipment.(3) For crop straw finely divided particles, ultra-fine grinding technology. optimize the design and calculate parameters of the straw crushing machinery with combined grinding technology, including analysis calculation and optimization of the feeding and cutting speed ratio. determination of upper and lower feed rollers and pressure regulating mechanism, determination of feed inlet parameters and feed roller diameter, design of blade and cutterhead, calculation of cutting power and crushing power, determination of hammer mechanism(hammer terminal velocity, hammer size, hammer number, hammer material and heat treatment, hammer and tooth plate gap).(4) Analyze key components with numerical simulation analysis that based on ANSYS Workbench, including strength analysis of the knife and the knife holder with static analysis module, the spindle system modal(natural frequency) analysis with modal analysis module.(5) Propose use cyclonic separation principle of ultra-fine grinding technology scheme. Numerical simulation based on ANSYS Fluent cyclone flow field analysis of the cyclone parameters calculation and structural design, the pressure loss calculation, meshing, numerical calculation settings, numerical simulation results were analyzed, including the cyclone air flow field the tangential velocity, axial velocity, radial velocity, pressure field, turbulence structure, velocity vector. Straw particles of a particle size of 0.074 mm separation experiment simulation, tracking simulation of particle trajectories and calculating the separation efficiency of 75.8%, separation efficiency is better.In production practice, applying the theory and technology of design and manufacture of dry and wet straw crushing machinery, the success of the fine crushing of corn straw and rice straw, straw particles, achieved good economic and social effect.