2022 Volume 78 Issue 7 Pages III_223-III_231
In this study, a mass production test of a new sewage sludge fertilizer using sewage sludge and regional biomass was carried out on a scale of 5 m3, and the obtained fertilizer was applied to a nitrogen mineralization test, a germination / growth test using Komatsuna (Brassica rapa var. Perviridis) and a tea cultivation test. We were able to mass-produce fertilizers with a total nitrogen content of 3.6 to 3.9% and a low heavy metal content. Since the new sewage sludge fertilizer contains 0.95% ammonia nitrogen, it is considered to be suitable for tea plants of ammonia-philic plants. The nitrogen mineralization test revealed that the new sewage sludge fertilizer has a significantly different mineralization pattern from the organic fertilizer rapeseed meal. In the test plot using the new sewage sludge fertilizer in the germination /growth test, the body mass index of 115 or more (control fertilizer plots 87 to 115, standard plot 100), and it was considered that they did not contain growth inhibitors. Furthermore, the tea cultivation test revealed the effectiveness of new sewage sludge fertilizer with a yield equal to or higher than that of the conventional organic fertilizer (rapeseed meal).