PEELING OF WHITE LUPINE GRAIN IN ROLLER MILLS

In cereal production, there are a number of methods for grain peeling. The process of peeling lupine grain having a specifi c form, which differs from the spherical one, includes grain crushing, sieve screening, and pneumatic separating. Independent variables characterizing the processing conditions include the gap between the rollers, grain moisture content, the speed of the rollers, and their slippage. Roller mills (crushers) were used for crushing. The rotational speed of the rollers was 300 and 600 min-1. During pneumatic separation, the air speed in the pneumatic duct corresponded to 7.5 m/s. It has been established that the gap
between the rollers and the grain moisture content signifi cantly affect the quality indicators of the ground product. As a result of the experiments, it has been found that an increase in the gap in the range of 1.0…2.5 mm and an increase in the grain moisture content from 8 to 13.2% result in the increased output of middlings and the average size of particles. However, the number of core particles with shell remnants increases too, and the output of tailings (mainly, shells) decreases after pneumatic separation. The output of marketable kernel middlings was about 70%. The technological process of white lupine grain peeling is based on the traditional equipment of cereal production. The results obtained suggest the possibility of the primary processing of white
lupine grain with such crushers to produce kernel middlings of the required fractional composition.

在谷物加工领域，存在多种谷物脱壳工艺。针对形态不同于球形的羽扇豆籽粒的脱壳工序，包含籽粒破碎、筛分以及气力分选三个环节。表征该加工工况的自变量包括辊间距、籽粒含水率、辊筒转速以及辊筒滑移率。本实验采用辊式磨粉机（roller mills，破碎机）完成破碎作业，辊筒转速设置为300 min⁻¹与600 min⁻¹。气力分选环节中，气力输送管道内的气流速度设定为7.5 m/s。研究证实，辊间距与籽粒含水率对破碎产物的质量指标具有显著影响。实验结果表明：当辊间距在1.0~2.5 mm范围内增大，且籽粒含水率从8%提升至13.2%时，中间产物（middlings）的产出率与颗粒平均粒径均有所提升；但此时带有壳屑的核心颗粒数量也随之增加，且气力分选后尾矿（tailings，主要为籽粒外壳）的产出率会降低。可售籽粒中间产物的产出率约为70%。白羽扇豆籽粒的脱壳工艺基于传统谷物加工设备搭建。本次研究所得结果显示，采用此类磨粉机对白羽扇豆籽粒进行初加工，即可获得符合指定粒度组成的籽粒中间产物。