Integrating industrial source and environmental sink towards chromium emission evaluation in China: Insights from the improved substance flow analysis

Abstract

The ubiquitous distributions of chromium (Cr) in environments pose threats to the health of human and ecosystem. The global output and consumption of Cr is extremely high and continuously growing, leading to cross-regional transportation and pollution via global trade. The present study identified the relationship between industrial sources and environmental sinks using the improved substance flow analysis. China, as the largest producer and consumer of Cr products, contains complete Cr related industries. Therefore, the Cr flow from Chinese eight key industrial sectors to environments in 2020 was illustrated in the research. Emission accounted for approximately 12.9%–21.8% of the flow, with the amount of 164 t in waste gas, 5.37 × 104-1.01 × 105 t in wastewater, 6.38 × 105-9.49 × 105 t in solid waste. Thereinto, ferrochromium manufacturing contributed 82.2%–85.4% to total wastes, and 1.52 × 104-2.53 × 104 t of Cr was evaluated to enter the soil accordingly. Owing to strict control for industrial wastewater and hazardous solid waste, treatment of general solid waste has become the primary pathway of Cr into the soil, contributing 77.8%–89.6%. National ferrochromium, stainless steel and refractory manufacturing contributed more effects on the soil, occupying 93.5%. Management and control of Cr in soil in China was later than other countries, such as America, Netherlands, Japan, Germany, and South Korea. However, China has issued a series of laws, regulations, action plans and standards in past decades to restrict emitter and promote industrial upgrading, which would gradually control Cr pollution and reduce the impact of industrial Cr consumption on the environment.