小型喷砂机柜式水幕排风罩矽尘防控有效性研究

目的探究柜式水幕排风罩应用于小型喷砂机防治矽尘的效果,提出粉尘通风防护设施新思路,有效保护劳动者职业健康。方法于2018年8至10月,选取某研究所喷砂间喷砂工艺配置的柜式水幕排风罩为研究对象,采用职业卫生调查、现场检测和气流组织物理相似模拟的方法,对其改造前后的局部排风设施设置情况、矽尘浓度、控制风速、气流组织进行现场检测和发烟测试,并结合设置情况进行分析与评估。结果气流组织模拟实验发现,改造后柜式水幕排风罩气流组织合理,能有效控制工件清扫过程矽尘逸散的全部范围。改造后,控制风速由改造前的0.01 m/s提高至0.53 m/s,控制风速提高98.1%;喷砂、开舱取件及清扫时接触矽尘(总尘)时间加权平均容许浓度(CTWA)由改造前的7.00 mg/m3降至0.50 mg/m3,矽尘(呼尘)CTWA由改造前的3.36 mg/m3降至0.27 mg/m3,其总粉尘和呼吸性粉尘CTWA降尘率分别为92.9%和92.0%。结论柜式排风罩与水幕除尘的一体化结合,优化了粉尘防治的组合方式,具有除尘净化效率高、节能环保等优点,可在同性质企业推广使用。

Study on the effectiveness of silicon dust prevention and control of small sandblasting cabinet type water curtain exhaust hood

Objective To explore the effect of cabinet type water curtain exhaust hood applied to small sandblasting machine to prevent and control silicon dust,and put forward a new idea of dust ventilation protection facilities to effectively protect the occupational health of workers.Methods From August to October 2018,the cabinet type water curtain exhaust hood of sandblasting room in a research institute was selected as the research object,and the methods of occupational health survey,on-site detection and physical simulation of air distribution were used to conduct on-site detection and smoke emission test on the local exhaust facilities,silica dust concentration,control wind speed and air distribution before and after the transformation line analysis and evaluation.Results The air distribution simulation experiment showed that the air distribution of the cabinet type water curtain exhaust hood was reasonable and could effectively control the whole range of silica dust emission during the cleaning process.After modification,the capture velocity was increased from 0.01 m/s to 0.53 m/s,and the capture velocity was increased by 98.1%.The time weighted average allowable concentration(CTWA)of silicon dust(total dust)during sand blasting,cabin opening and cleaning was reduced from 7.00 mg/m3 to 0.50 mg/m3.The CTWA of silica dust(exhalation dust)was decreased from 3.36 mg/m3 to 0.27 mg/m3,and the CTWA dust reduction rates of total dust and respirable dust were 92.9%and 92.0%,respectively.Conclusion The combination of cabinet type exhaust hood and water curtain dedusting optimizes the combination mode of dust prevention and control.It has the advantages of high efficiency of dedusting and purification,energy saving and environmental protection,and can be popularized and used in enterprises of the same nature.