Scenario Analysis of Water-Saving Potential in Yeast Manufacturing Industry under the Guidance of Water Intake Quota

While yeast manufacturing consumes a large amount of water per unit of product, water use efficiency varies widely within the industry due to disparity in water-saving technologies. By stipulating water intake per unit of product, the Norm of Water Intake––Part 41: Yeast Production (GB/T 18916.41-2019) will standardize production water use and improve the water-saving level of the yeast manufacturing industry. This paper estimates the industry’s production capacity from 2020 to 2024 through regression analysis. It examines the distribution of water use efficiency under different policy scenarios based on the standard for water intake, including the business-as-usual scenario, the bottom-line scenario, the ideal scenario, and the expected scenario. Then, the water use of the yeast manufacturing industry under different scenarios is calculated, and the water-saving potential is analyzed by comparing it with the business-as-usual scenario. The results indicate that depending on the intensity of policy implementation, the average annual water savings will range from 2.5 × 106   m 3 to 14 × 106   m 3 . The cumulative water savings will add up to 16 × 106   m 3 to 51 × 106   m 3 in the next five years, which is very large.