Kitchen greasing wastewater, which contained high concentration of volatile fatty acids, was treated by IC reactor. Causes of acidification during start-up stage were analyzed. It takes measures to restart IC after acidification and operation of IC during recovery phase was investigated. The results show that sharp declination of temperature, fast rise of organic loading and special characteristics of kitchen wastewater cause acidification of IC. The effluent COD sharply increases from 0.548 mg/L to 2.546 g...