Dingxi City, located in the Gansu Province, is well-known for its long history of potato cultivation. The region’s favorable climate and soil conditions have made it one of the best areas for potato seed breeding and storage in China. With over 2.8 million acres of land dedicated to potato farming and an annual production of approximately 5 million tons, potatoes have become a cornerstone of Dingxi’s rural revitalization and economic transformation.
However, the potato starch processing industry, a major pillar of Dingxi’s agricultural economy, has faced significant environmental challenges, particularly in the treatment of wastewater. The wastewater generated during potato starch production is highly concentrated and voluminous, and traditional treatment methods often fail to meet the stringent environmental standards set by the government. These difficulties have hindered the industry’s potential for growth, creating a pressing need for innovative solutions.
In December 2023, Dingxi City launched a pilot project aimed at addressing the wastewater treatment issue while promoting the sustainable development of the potato starch processing industry. The city’s government has adopted a collaborative approach involving municipal-level guidance, county-level coordination, and active participation from enterprises. The project focuses on three key methods: fermentation in black membrane biogas pools, treatment through municipal wastewater treatment facilities, and the use of wastewater as fertilizer for agricultural fields.
One of the most significant breakthroughs has been the introduction of black membrane biogas pools, which facilitate anaerobic fermentation of organic waste, including wastewater. This process has proven highly effective in converting waste into valuable resources. By harnessing the biogas produced, the system generates renewable energy, reducing the reliance on external energy sources and contributing to a more sustainable operation. In addition, the nutrient-rich effluent produced through fermentation is being used as fertilizer, benefiting local farms and enhancing soil quality.
The city’s government has been proactive in seeking out best practices from other regions. In February 2024, a government delegation visited Ulan Chabu in Inner Mongolia and Guyuan in Hebei Province to study successful wastewater treatment models, including large-scale biogas systems and the use of wastewater in agricultural applications. The insights gained from these visits were instrumental in shaping Dingxi’s strategy for implementing similar projects, tailored to the region’s specific needs.
Thanks to these innovative measures, Dingxi has already seen impressive results. By September 2024, four enterprises had completed their technology upgrades, investing over 50 million yuan. These upgrades have not only solved the wastewater treatment problem but have also generated economic benefits, such as cost savings in production and the extension of the production cycle. The biogas fermentation system has lowered operational costs by approximately 5.6 million yuan annually, while reducing the need for external raw material sourcing by utilizing the 3,500 acres of land leased for potato cultivation.
The environmental impact has been equally significant. The new system has transformed the way wastewater is handled, shifting from mere pollution control to an integrated approach that promotes the recycling of water and nutrients. The wastewater now serves as a resource for agricultural production, reducing pollutant discharge and improving the overall environmental quality.
Dingxi City’s efforts to tackle wastewater challenges in the potato starch processing industry are a testament to the power of innovation and collaboration. By adopting green technologies such as black membrane biogas fermentation and resource recycling, Dingxi is not only solving its environmental problems but also advancing agricultural sustainability. The project’s success is paving the way for a new era of clean production in the potato industry, offering valuable lessons for other regions and industries facing similar challenges.
