Coal-fired power industry water-energy-emission nexus: A multi-objective optimization

The Chinese government has launched a guideline to lead power plants to more suitable technological pathways for meeting the strict “ultra-low emission” (“ULE”) standards to reduce air pollution emissions of the coal-fired power industry. Considering the complex interrelations between water, energy and emission, a quantifiable method of choosing the feasible technology sets for 6 multi-objective optimizations goals (MOGs) in the concept of water-energy-emission nexus (WEEN) was developed in this study. The results showed that the 16 technology sets can meet the “ULE”, which could mitigate at least 72% of the current emissions at the cost of up to 17% increase of water/energy consumption. Specific technology sets were identified for 6 different MOGs with the coordinate consideration of WEEN. The comparisons among the 6 MOGs indicated that (1) the investment cost was not a vital factor in the optimizing procedures; (2) dust reduction was sensitive to the water/energy optimization goal due to the synergic dust removal effects of the desulfurization technologies; (3) the water for WEEN was easier to reduce than the energy for WEEN from the perspective of the tradeoffs of emissions. The identified 12 feasible technology sets for WEEN (-cost) would shed lights on more coordinately policy making process.