| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To sufficiently decompose oils and fats and also to reduce excess sludge while achieving a low cost. <P>SOLUTION: While a soluble organic substance in oils and fats-containing wastewater is treated by BOD decomposing bacteria to the oils and fats-containing wastewater, for example, which are proliferated according to biological treatment in a bioreactor 1, to generate sludge, the sludge which contains these BOD decomposing bacteria and oils and fats decomposing bacteria is concentrated by a sludge concentration device 5 to provide the concentrated sludge, and this concentrated sludge is heated by a heating device 6. Then, while the heating temperature is set to a temperature at which many BOD decomposing bacteria are sterilized and many oils and fats decomposing bacteria are not sterilized, thereby sterilizing the BOD decomposing bacteria and suppressing decomposition of the soluble organic substance to reduce the excess sludge, many oils and fats decomposing bacteria are not sterilized to allow decomposition of the oils and fats by the oils and fats decomposing bacteria, and the concentrated sludge is heated like this. Thus, a running cost for carrying out heating is reduced compared with the case in which sludge that is not concentrated is heated. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
