GRANULE-FORMING METHOD AND WASTE WATER TREATMENT METHOD

A granule-forming method using a semi-batch reaction tank, wherein: operation cycles of a first operation cycle for performing a biological treatment step at a first sludge load and after the first operation cycle, a second operation cycle for performing the biological treatment step at a second sludge load are performed repeatedly; the first sludge load is set so that the soluble BOD concentration in the semi-batch reaction tank at the time of completion of the biological treatment step of the first operation cycle does not decrease to a threshold value or less; and the second sludge load isset so that the soluble BOD concentration in the semi-batch reaction tank at the time of completion of the biological treatment step of the second operation cycle is at or below the threshold value. 种使用半间歇式反应罐的颗粒形成方法，其中：重复实施操作循环，其包括在第污泥负荷下实施生物处理步骤的第操作循环和在第操作循环之后实施的、用于在第二污泥负荷下实施生物处理步骤的第二操作循环；第污泥负荷设定为，使得在第操作循环的生物处理步骤完成时半间歇式反应罐中的可溶性BOD浓度不降低至阈值以下；并且第二污泥负荷设定为，使得在第二操作循环的生物处理步骤完成时半间歇式反应罐中的可溶性BOD浓度为阈值以下。