Exploring the cost of wastewater treatment in a chemical industrial Park: Model development and application

In light of the environmental policy orientation of continuous upgrading emission limits, quantitatively understanding the comprehensive cost of wastewater treatment of chemical industrial parks, a common landscape globally, will be vital for facilitating sustainable water management of the parks. This study modeled the economic cost of wastewater treatment in chemical industrial parks from the perspective of life cycle thinking. The full-process cost of wastewater treatment is accounted, including freshwater withdrawal, construction and capital costs of wastewater treatment facilities, operation costs, sludge treatment costs, and 'feed-in tariffs' of wastewater to centralized wastewater treatment plants (CWWTPs) of the park. After applying the model to HSEDA, a typical chemical industrial park, we found the total wastewater treatment cost of the chemical industrial park in 2016 was 654 million Chinese Yuan (about 97 million USD), accounting for 29 % of the tax revenue of the park. Energy, chemicals, and labor costs in the sum accounted for more than 60 % of the full-process cost. The cost of freshwater withdrawal, in-plant treatment cost, and CWWTP cost accounted for 54 %, 33 %, and 13 % of the total cost, respectively. The top two pillar industries the dyestuff manufacturing industry and the pharmaceutical industry, have a cost of 29 CNY and 21 CNY per ton of wastewater, respectively. Moreover, the marginal cost increment associated with a much stricter emission standard by targeting TN control is discussed by employing different technologies. Finally, key measures for improving wastewater treatment in the chemical industrial park are proposed.