Research On The Effect Of Residual Activated Sludge Disintegration With Single Frequency-double Frequency Ultrasonic Combined Alkali Pretreatment Technology

In recent years, with the development of economic construction in rapid population growth, the treatment facilities of municipal sewage are insititutionalized, at the same time, they produced a lot of surplus sludge. There are a great manpower during the sludge handing. At present, surplus sludge treatment become difficult questions to us. The traditional anaerobic reaction have many weaknesses such as digestive slow, time-consuming, long reactor, take up the space is large, etc. We adopt a series of measures to improve the pHysic-chemical treatment for the surplus sludge.The value of NaOH∕TS were 0.02, 0.04, 0.09 respectively. When the surplus sludge was treated by superaudible combine NaOH, we tested the pH, protein, sugar, EPS of the surplus sludge supernatant. We found that the pretreatment of surplus sludge by superaudible combine NaOH were better than the surplus sludge. The concentration of SCOD, protein, sugar were increased, while the pH was decreased followed time. By comparison, more NaOH combine double- frequency superaudible can improve the cracking effect. The optimum condition: NaOH∕TS was 0.09, superaudible frequency was (28+40) kHz. The concentration of SOCD were increased from 666 mg·L^-1to 13184 mg·L^-1after 60 min. The concentration of protein were increased from 194.6 mg·L^-1to 5782 mg·L^-1after 60 min. Otherwise, we discussed the effect of superaudible to the cell cracking condition by compared quantity of protein in the EPS layer of LB and TB of the surplus sludge.VFA. The concentration of organics were more in the pretreated sludge. The protein, sugar of sludge can produce many VFA. When NaOH∕TS were 0.09 and frequency were (28+40) kHz, the effect of produce acid was obviously, but due to the concentration of NaOH was too much, the time was longer than NaOH∕TSwere 0.04 and frequency were (28+40) kHz.