Objective To identify and predict the level of exposure of occupational hazardous factors and the degree of occupational hazards during the production and operation of the ammonium rhenate project using copper smelting flue gas as raw material, and to analyze key control points, so as to provide a reference for the control of occupational hazards during the operation of the proposed new ammonium rhenate production project using copper smelting flue gas as raw material.

Methods An ammonium rhenate production project from an enterprise in Hubei, China was selected as a reference project. According to the Specifications of Air Sampling for Hazardous Substances Monitoring in the Workplace (GBZ 159-2004), the individual dust concentration, noise levels, and and chemical hazardous factors levels for workers in the main positions and work types of the reference project were determined. According to the Occupational Exposure Limits for Hazardous Agents in the Workplace—Part 1: Chemical Hazardous Agents (GBZ 2.1-2019) and Occupational Exposure Limits for Hazardous Agents in the Workplace—Part 2: Physical Agents (GBZ 2.2-2007), the occupational hazardous factor exposure levels of the reference project were evaluated, and the key control points were analyzed.

Results In the ammonium rhenate project production operation, there were occupational hazardous factors such as dust (calcium hydroxide dust and ammonium rhenate dust), ammonia, hydrogen sulfide, arsine, arsenic and its compounds, sulfuric acid, lead and its compounds, and noise. The calcium hydroxide dust concentration at the acid pickling tank feeding port was 8.02 mg/m³; the noise intensity at locations such as the waste acid leaching vacuum pump, filter press vacuum pump, acid pickling mixer, acid pickling vacuum pump, extraction vacuum pump, and concentration crystallization vacuum pump was between 85.2-88.4 dB(A); the concentration (intensity) of occupational hazardous factors in other workplaces met the national occupational health standard requirements.

Conclusion Calcium hydroxide dust, ammonium rhenate dust, ammonia, hydrogen sulfide, arsine, sulfuric acid, arsenic and its compounds, lead and its compounds, and noise are the main occupational hazardous factors during the operation of the ammonium rhenate production project using copper smelting flue gas as raw material. The proposed project using the same process needs to strengthen the prevention and control of calcium hydroxide dust and noise as occupational hazardous factors during production and operation.