Scenario simulation and regulation policy optimization of industrial enterprise production water considering scale heterogeneity: A case study in the chemical industry

To build a water-saving society, it is crucial to integrate the water-saving priority concept into the production and operation of enterprises and optimize the regulation policy. Hence, this study constructs a scenario simulation model for production water decision-making. Taking the chemical enterprises in Zhenjiang as an example, it investigates the response mechanism of water use decision-making of enterprises of different scales under designed scenarios comprising three policies (i.e., water price, subsidy, and penalty). Moreover, considering the government’s different preferences for environmental and economic benefits, the particle swarm optimization (PSO) algorithm is used to find the optimal combination of water-saving policies for enterprises of different scales. The results show that the response pattern of enterprises to changes in government water-saving regulation policies is heterogeneous by scale. Additionally, multiple policy combinations can better achieve the tradeoff between water-saving and economic benefits. The PSO can optimize the objective function composed of water-saving and economic profit under different weights. Considering the scale heterogeneity, it is more reasonable to formulate policies by scale than uniform policies. Finally, based on our findings, this study proposes targeted policy recommendations to promote water conservation in industrial enterprises.