| In this paper, regarding the maize alcohol wastewater treatment project of one plant as a research object, through consulting a large number of domestic and foreign literatures, the process of maize alcohol production, the quality of maize alcohol wastewater and the current situation of study on treatment for this kind of wastewater were discussed briefly, which had provided theoretical basis for the project adopting internal circulation anaerobic reactor (IC)+conventional activated sludge process for maize alcohol wastewater. By analyzing the reaction mechanism, operation rules and affecting factors of IC reactor and conventional activated sludge process, the start-up and operation condition of the main process of IC+ conventional activated sludge process treating maize alcohol wastewater were mainly studied, which provided a set of empirical data for the application of the combined process in the treatment for this kind of wastewater. In short, the study results had certain theoretical significance and application value.The two IC reactors (recorded as 1# and 2# respectively) were inoculated with digestion floc sludge from Huixian Baiquan Winery and digestion granular sludge from Mengzhou Winery, respectively. Because of the different seeding sludge, two different programs of start-up for the two IC reactors were adopted, as shown below. After inoculated with seeding sludge, the IC reactor(1#) had been soaked by water for 4-5 days, and the following start-up process was divided into three stages. In the first stage, feeding wastewater of low COD concentration below about 3000mg/L; In the second stage, increasing the COD in influent gradually to the concentration of the raw wastewater; In the third stage, feeding the raw wastewater. Intermittent pulse feeding mode was adopted during the whole process.The start-up process of the IC reactor (2#) maintained a stage, i.e., the wastewater after pretreatment entered the IC reactor directly. Some time later, if the VFA in effluent was below 400mg/L, the pH in effluent was above 6.5, the removal efficiency of COD reached 80%, and the gas production was normal, the feeding flow was increased gradually until the organic loading reached the design loading. When the start-up of the two reactors was finished, their volume loading reached 11.15kgCOD/(m3·d) and 12.16kgCOD/(m3-d), respectively, and the removal efficiency of COD was both above 90%.The seeding sludge (aerobic sludge) of the conventional activated sludge process was taken from the municipal sewage treatment plant in the city. During the start-up period, the synchronization process was used to cultivate and domesticate sludge, i.e., at first, a small amount of clean water was introduced to the aeration tank and the aeration lasted 24 hours (without outlet), then the effluent from the anaerobic reactor and some clean water was introduced to the aeration tank until the water level reached the effective depth, followed by aeration and sedimentation. Aeration was alternated with sedimentation for two hours respectively, and so on. The supernatant was partly discharged and some fresh wastewater was added per day, then the feeding flow of the fresh wastewater was increased gradually, then monitored each day Influent and effluent quality and performance to reflect the activated sludge indicators, such as SV and MLSS, etc. to monitor the cultivation of activated sludge, when SV increased to about 30% and MLSS increased to about 4000mg/L, which showed that the cultivation of activated sludge was basic successful. The removal efficiency of COD was up to 90% after the project was successfully started up.
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