新型空化器及其在污泥细胞破解中的应用

A new-type cavitation generator and its application on surplus sludge cells disintegration

研究开发了一种新型空化器用来破解剩余污泥,它具备通气调节和孔板旋转的功能。这样的设计可以防止堵塞和节约能耗。该空化器工作时可以产生直径2~5μm的“气核”,从而提高空化初生的空化数,降低能耗。孔板旋转产生的轴向推力可使小孔中的堵塞物脱落,有效防止小孔堵塞。在实验室内应用该装置破解剩余污泥的生物细胞,并通过测定细胞内可溶性COD的溶出率来评价污泥破解效果。研究制造了空化作用破解污泥细胞系统,该系统可以利用新型空化器连续处理剩余污泥,并且可以根据研究需要改变通气比和调节管道流速等运行工况。在实验室内应用该系统破解剩余污泥生物细胞,通过调整通气比和管道流速,探索最优运行工况。根据正交试验结果,系统运行的最优工况为通气比1.4%、空化数1.8,此时可溶性COD（SCOD）的溶出速率为0.06%/s。在最优运行工况下,破解1 kg剩余污泥的功率为560 W,采用该系统处理30 min后,95%以上的污泥生物细胞可被破解。按处理时间30 min计算,处理1 m3剩余污泥的耗能约1 000 MJ,比超声空化法低40%左右。该系统还具有装置简单、无二次污染等优点,可为污泥细胞破解提供更为经济、有效的技术和方法。

The paper is to propose its development of a new-style cavitation generator for regulating the ventilation and the pore plate rotating function so as to disintegrate the excessive sludge cells and get rid of blockage with the economy of energy consumption. As a matter of fact, the ＂gas nucleus＂ generated in a diameter area of 2 -5 μm can help to successfully increase the cavitation inception numbers, and reduce the energy cost. The rotary pore plate may also generate the axial thrust which is in a position to get rid of the plugging matters so as to overcome the pole blockage effectively. The above mentioned new-style cavitation generator can be used to crack the biologic cells in the surplus sludge in a laboratory, and the soluble chemical oxygen demand （SCOD） out of the biologic ceils is measured to evaluate disintegration effects. The cavitation system （CS） has been also designed and used to treat the surplus sludge in a continuous way, with the operation conditions adjusted in accordance with the research demands. According to the results of the orthogonal experiments, the optimal operation condition should be taken when the ventilation ratio is kept at a percentage of 1.4% with the cavitation number being 1.8, fhen SCOD dissolution velocity is kept at about 0. 06%/s. For, over the rate of 95% , it would be possible for the sludge biological ceils to get cracked as a result of 30 min treatment. Nevertheless, if the treating time is exactly up to 30 min, about 1 000 MJ energy would be cost to treat 1 m3 surplus sludge. The energy consumption of the said system has thus to be fixed at a rate of 40% or so, that is, less than the ultrasonic cavitation. Besides, with the new-style cavitation generator, the given system can have other advantages, such as, simple in structure, and free from the secondary pollution. Thus, the system can be expected to provide a more effective and economical method for the surplus sludge bio-cells disintegration.