| Syrup wastewater belongs to a category of high concentrated organic wastewater. Having the unique charateristics such as high concentrated organic pollutant and solid impurity, changeable water quality and so on. If it is not properly treated, it could cause serious pollution to the environment. At present, combined technology of physic-chemical and biochemical treatment is usually adopted to sovle the problem. Since that syrup industry quickly developped only these years, research on syrup wastewater is fewer compare to other high concentrated organci waserwater as brewery wastewater, alcohol wastewater and starch wastewater. The existing projects are mainly designed following other high concentrated organic wasterwater treatment technology, without cnsidering the charaistics of syrup wastewater, many problems occur. So it is essential to make some research on technics of syrup wastewater treatment and quest for the suitable controlling parameters.In this research, an experimental study on syrup wastewater with hydrolytic acidification-SBR technology has been carried out, through analyzing the COD, BOD5 and SS removal effect of the combined technology, the optimal controlling parameters during the start-up and circulate of the combined technology is explored. The results showe that:1. When taking a methed of low load inoculated biofilm formation to startup the hydrolytic acidification reactor, 22 days of operation showed that the biofim growed well and that the removal rate of COD was between 42.2%~47.3%, the removal rate of SS was between 76.2%~82.4%. It took few days to complete the start-up process showed that syrup wastewater is easy to hydrolytic and acidificate.2. Results of the single factor experiment showed that when taking hydrolytic acidification reactor to treat syrup wastewater, the optimum HRT was 8h and the optimum agitation interval time is 2h. Under this condition, when the COD of influent was 3838~4310 mg/L, COD, BOD5 and SS removal rate of the wastewater stabilized at about 45%, 28% and 78%. It was demonstrated that the SS was removed mostly through the hydrolytic acidification process, BOD5/COD increased from 0.45~0.53 to 0.60~0.66, which can create a suitable condition for the subsequent SBR process and enhance the efficiency of the combined technology.3. The activated sludge domestication process was an essential step when using activated sludge technology to treat with higher concentrated organic wastewater. In this resrarch, some high efficiency activated sludge which could endure higher extension of COD loading was obtained through 24 days'domestication process, it was floccule and filemot, its SV30 was between 20%~35% and its SVI was between 70~100.4. Taking SBR process as the subsequent treatment after hydrolytic acidification process, it was proved that the optimal MLSS concentration of SBR was about 3500~4000mg/L, and the optimal aeration rate was 0.1m3/h, the times for aeration and settlement were 7h and 1h, respectively. Under this condition, COD, BOD5 and SS removal rate of the influent were between 94.3%~97.1%, 96.4%~98.1% and 67.1%~73.2%, the continuous operation experiment proved that the effect of SBR process was also stable.5. Having got the optimal controlling parameters of each unit technics, continuous operation experiment about syrup wastewater treatment with hydrolytic acidification-SBR technology was taken, and the anti-impact load ability was analyzed during this process. The results showed that the combined technology had stable removal effect and strong anti-impact. After treated by the combined technology, the removal rate of COD, BOD5 and SS were about 96.7%~97.8%, 97.7%~98.7% and 92.4%~94.2%, and the last effluent could reach the second standard of G8978-1996.In conclusion, when hydrolytic acidification technology is used in syrup wastewater treatment, the removal efficiency of organic contaminant is high, and the combined technology also has the unique charateristics of small covering size, high efficiency of equipment, flexible modulated operation, strong anti-impact and so on, so it can be popularized in actual application of ayrup wastewater or some other high concentrated organic wastewater.
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