China: New tech turns potato effluent into fertilizer

Scientists in China have developed a way of making fertilizer from waste water discharged by potato processing plants, solving a pollution problem which has held back China’s potato ambitions. “For years, there has been no technical solution to this problem, forcing environmental authorities to close more than 10,000 small plants, which has hurt the potato market and farmers,” said Liu Gang, researcher with the Chinese Academy of Sciences, Lanzhou institute of chemical physics. Liu’s team has developed technology that can halve the chemical oxygen demand (COD) of the effluent by removing starch, fiber and protein. The processed water does not need to be dumped either, because of its high nitrogen, potassium and phosphorus content make it a perfect irrigation water. More