Abstract:

The new-type mechanical rotary disk(MRD), which was used for the experiment of excess sludge disintegration combination with ultrasound, was manufactured by independent design to improve the disintegration effect. To investigate the MRD disintegration effect, the experiments under different operation conditions were carried out. The results showed that d(the distance between the plates) and T_m(the disintegration time) were the important factors to influence SCOD₊(the added value of solubility chemical oxygen demand) and EDR(energy disintegration ratio). The SCOD₊ was 3130 mg·L^-1 after 25 min of MRD disintegration under the condition that d was 1.5 mm and the revolving speed was 2300 r·min^-1, which presented that the disintegration was effective. According to the center combination experimental design of Central-Composite based on the response surface method, SCOD₊ and EDR were considered as response to paid attention to the energy efficiency. SCOD₊ and EDR were 7871.78 mg·L^-1 and 8.475 mg·L^-1·kJ^-1 under the optimal conditions that d, T_m and T_u(ultrasound disintegration time) were 2.76 mm, 10.89 min and 17.2 min, respectively. The results were respectively 3.02 times and 2.7 times of What used MRD（2610 mg·L^-1，3.11 mg·L^-1·kJ^-1）and 2.48 times and 2.6 times of that used ultrasonic（3170 mg·L^-1，3.26 mg·L^-1·kJ^-1）under the same total disintegration time.

Key words: waste treatment, optimal design, microstructure, mechanical rotary disk, ultrasonic, response surface method

摘要：

采用自主设计并制造的机械转盘剩余污泥破解装置对污泥进行破解处理，并联合超声技术以提升破解效果，考察不同运行条件对污泥破解效果的影响，采用响应面法优化处理参数，通过扫描电镜观察破解污泥的细胞形态。实验发现：盘间距离（d）和转盘破解时间（T_m）是影响机械转盘剩余污泥破解液溶解性化学需氧量的增加值（SCOD₊）和效能比（EDR）的重要因素；在d=1.5 mm，转速为2300 r·min^-1运行条件下破解25 min时SCOD₊为3130 mg·L^-1，破解效果良好。根据Central Composite Design实验设计原理，注重剩余污泥破解的能源利用效率，以SCOD₊和EDR为响应指标对机械转盘联用超声破解参数进行优化，当优化条件为d=2.76 mm，T_m 10.89 min，T_u（超声处理时间）=17.2 min时，剩余污泥破解液SCOD₊=7871.78 mg·L^-1，EDR=8.475 mg·L^-1·kJ^-1，在相同总处理时间下分别是单独机械转盘法（2610 mg·L^-1，3.11 mg·L^-1·kJ^-1）的3.02倍、2.7倍，单独超声法（3170 mg·L^-1，3.26 mg·L^-1·kJ^-1）的2.48倍和2.6倍。

关键词: 废物处理, 优化设计, 显微结构, 机械转盘, 超声, 响应面法