| 摘要 |
<p>PURPOSE: To provide a method for efficiently removing BOD components, COD components, and nitrogen content by the biological treatment of residual wastewater after boiling of a small fish which has high salt concentration, BOD, and COD, especially wastewater discharged in a production process of small dried sardines. CONSTITUTION: In a method for treating residual wastewater after boiling small fish in which immobilzed microorganisms immobilzed inclusively on a polymer type carrier are used, especially, high temperature wastewater after boiling small fish, after being cooled at 40 deg.C or below, is set in sequence to an anaerobic tank filled with immobilized microorganisms, an aeration tank filled with immobilized microorganisms, and a precipitation tank. Besides, treated water from the precipitation tank or the aeration tank in an amount of 1-5 tmes wastewater introduced into the anaerobic tank is circulated so that 90% or more of each of BOD, COD, and total nitrogen is removed.</p> |
