Use of fertilizer from sewage increasing

October 13, 2017

TOKYO- "Bistro Sewage" programs are being promoted in many parts of Japan, using mud-like products of sewage treatment as fertilizer to grow vegetables.

The project, in its fifth year, is now under way in 16 prefectures. The land ministry and other concerns decided in April to dub such vegetables "Junkan Sodachi" (cyclically nurtured).

At Japan's largest sewage technology fair, held at the Tokyo Big Sight exhibition center in August, the Gesuido Koho Platform, an industry-government-academia organization working to raise public awareness on sewage, handed visitors to its booth Junkan Sodachi cucumbers, corns and other vegetables raised in Nagano and Aomori prefectures.

"Many visitors from local governments showed willingness to promote the project," a GKP official said.

The sludge, treated water, heat and carbon dioxide produced in the process of sewage treatment at sewage disposal plants are full of three main macronutrients--nitrogen, phosphorus and potassium. The project converts sludge into fertilizer, utilizes treated water for rice production and laver culture and uses heat and CO2 for greenhouse cultivation of vegetables. Jiji Press