In order to remove the impurities in the solid forming material of crop straw, the material was screened and sorted and the heat value of the screening material was tested, the impurity classification and source were studied, and the compost trommel screen screening and impurity removal system was designed. The results show that the impurities can be divided into metal, multi-plastic fabric, sand and dust, etc. Harvest, farmer storage, transportation, site management and other impurities may be produced, among which in this experiment, site management produced more impurities, accounting for about 3% of the total material quantity. In the impurity screening, the inclination Angle of the roller screen is 3° ~ 9° and the rotating speed is 20 ~ 32 r/min. The method of selecting length-diameter ratio according to the screening efficiency is given.
Our country has a rich crop straw resources, straw solid molding is one of the simple and effective methods of energy utilization, which can realize efficient combustion and low pollution emission at the same time. The large impurity content in the straw solid molding raw material will affect the molding process and the quality of the molding fuel, and then affect the combustion efficiency of the corresponding boiler and stove. The characteristics of organic compost were studied. On this basis, it was sorted by roller screen.
The compost trommel screen system for separating small particles is designed and tested. According to the test, two targets (roll
Cylinder screening rate, material residence time) and three parameters (roller speed, Angle, length-to-diameter ratio compost trommel screen length and diameter ratio). At present, there is no scholar to study the characteristics of straw solid forming impurities and its sorting mode. In order to study the characteristics of impurities in crop straw materials, manual screening was used to obtain the relevant data of impurity type and component content. In order to separate impurities, according to the characteristics of crop straw materials and impurities, the roller screen with adjustable dip Angle and rotational speed is used to study the sorting characteristics and rules of the roller screen with compost trommel screen sorting efficiency and material residence time as indicators. In order to provide data support and theoretical reference for the research on the separation process of crop straw solid forming material impurities.
Compost trommel screen work, the material in the roller turn the material layer loose through the screen, and is not easy to plug the screen, and solid molding crop straw material has a range of granularity distribution, fiber shape, accumulation density is small, large external friction Angle and other characteristics, suitable for roller screening. Designed for the test of straw impurities sorting roller screen machine structure, such as the sieve barrel length of 1900 mm, diameter 600 mm, Angle 0° ~ 11° adjustable, motor speed is controlled by the frequency converter adjustable, through the chain drive and roller spindle connected to drive the roller screen rotation.
