摘要
茶尘是影响茶叶品质和损害制茶工人身体健康的重要因素。通过对茶厂精制车间茶尘的浓度、组成和粒度的研究,为茶厂粉尘控制提供理论依据与技术途径。试验采用在线检测、收集的方法,以红茶精制的5道工序各自所产生的粉尘为材料,设置近旁和1.2 m处2个距离水平,于茶尘粒径≤2.5μm、2.5μm<φ≤10μm分别在4、8 h时间条件下,进行浓度、组成及粒度的相关分析。结果表明:在浓度方面,当φ≤2.5μm时,最大值出现在分筛机,分别为65.321 mg/m3(近旁、8 h)、47.354 mg/m3(1.2 m、4 h)和44.987 mg/m3(1.2 m、8 h),而当2.5μm<φ≤10μm时,撩筛机产生的茶尘浓度最高,分别高达29.667 mg/m3(4 h)、26.919 mg/m3(8 h);比较设备近旁和1.2 m处,分筛机近旁>1.2 m处,抖筛机和风选机与之相反,紧门机无变化。在组成与粒径方面,撩筛机和风选机可入肺茶尘数量是1.2 m处>近旁,设备1.2 m处可入肺茶尘数量占比最高达82.1%,出现在风选机;茶尘总粒度(包括φ≤2.5μm和2.5μm<φ≤10μm)为近旁<1.2 m处,分别为59.7%、67.8%;紧门机2处不同类茶尘所占的比重均相同。上述结果说明,不同工序茶尘的物理特性存在较大差异,各工序茶尘物理特性差异与设备的机械性能、工艺参数及其空间布置直接相关。
Tea dust, a production waste, can influence tea quality and be harmful to workers＇ health. It isnecessary to analyze the concentration and particle size（φ） composition of tea dust in refined factory, thus toprovide relative theories and technical approaches for tea dust control. The experiments were designed as：（1） setting 2 distance levels of around and 1.2 m away from the machines;（2） time setting（4 h and 8 h afterworking）;（3） on-line detection and collection tea dust from 5 processes in black tea making. The results showedthat the maximum dust concentration appeared in the vicinity of the screening machine（8 h, φ≤2.5 μm）, up to65.321 mg/m^3. The dust density（φ ≤2.5 μm） of 1.2 m away from the machine was also high, which was47.354 mg/m^3（4 h） and 44.987 mg/m^3（8 h）, respectively. When the particle size was from 2.5 to 10 μm, theup-lifting screening machine produced dust most, the figure was 29.667 mg/m^3（4 h） and 26.919 mg/m^3（8 h）,respectively. From the perspective of distance, there was more dust at 1.2 m away from the shaking sievemachine and winnowing machine, however it was on the contrary at the screening machine. The dust densityfrom the different distances of the tight door machine was similar. With the special emphasis on respirabledust, we found that 82.1% of the dust was respirable at 1.2 m away from the winnowing machine. The dustdensity data（φ≤10 μm） implied that closer distance was polluted more severely than 1.2 m away with the record of 59.7%（φ≤2.5 μm） and 67.8%（2.5 μmφ≤10 μm）, respectively, but this was not applied to thetight door machine. In conclusion, the physical properties of tea dust vary with different technique processes,and the differences of the physical properties are directly related with mechanical performance of the machine,process parameters and space layout.
出处
《中国农学通报》
2016年第7期109-114,共6页
Chinese Agricultural Science Bulletin
基金
安徽省青年创新基金项目"精制茶厂粉尘的理化特性及成因机制研究"(14B0840)
安徽省农业科学院学科建设项目"名优祁红机械化加工技术集成研究"(15A0830)
安徽省茶叶产业技术体系红茶加工岗位
国家现代农业产业技术体系专项资金(CARS-23)
关键词
茶尘
精制茶厂
物理特性
比较分析
tea dust
refined factory
physical properties
comparative analysis
