| With the development of dredging engineering and construction in the port, channels and rivers of our country produce large numbers of dredged sludge every year. It has been urgent technical problems to be solved in the field of environmental protection. How to shaken off the hardship from the traditional places and to shorten the drying time through technological innovation were matters of technology.Dewatering was an important technology for sludge recycling process. Different types of flocculants and compounding flocculants were chosen in the paper. Finally, the best system for fast dehydration of sediment was confirmed through the specific small-scale simulation experiments according to the indicators of the filter cake moisture, COD values of filtrate, the absorbency of the silt supernatant and ξ-potential of dewatering sludge supernatant. Studies showed that the flocculants made in this experiment could expedite significantly the settling velocity. Under the optimum conditions, the water-containing rates of cakes changed from57.87%to22.44%.The COD value,ξ-potential,absorbance value and the zeta potential and turbidity all reduced by different degrees. As a result, the quality of residual water was improved obviously.However, the current flocculants have some disadvantages. Therefore, low cost, low environmental side effects of flocculants become increasingly important. The natural organic polymer flocculants were cationic modified by agricultural waste rice husk, as raw material. Sedimentation effect, turbidity, absorbance, Zeta and the diameter of particle are discussed by complex formulation of CPAM and flocculants. The results showed that the complex flocculants has good flocculation. When flocculants were50mg·L-1to60mg·L-1with CPAM, sludge can be quickly dehydrated in a short time and water quality improved obviously, turbidity down to3.28NTU.The flocculants opened a wider area for the reuse of agricultural waste and research of flocculants.In this paper, small sludge dewatering equipment simulated large-scale sludge dewatering unit operation process so that the mobile modular sludge dewatering process could explore. Some influence factors were studied, such as different proportion of mud and water, the different kinds of flocculate and different mass etc. According to analyzing the residual turbidity, absorbance, the rate of water content of sludge treated to sum up the optimum technique of sludge treatment, including the optimum proportion of mud and water, the optimum flocculate’s mass. And then provided some advice for enlarge in industrial produce. The results showed that the best effect was residence time within the120-160min when the sludge to water ration was1:4.Lastly, laboratory small experimental were zoomed to processing volume for4tons. In comparison with blank, dehydration rate and the water quality were observation. Results indicated that the dehydration rate and displacement of joined flocculation coagulation pharmaceutical group were far greater than the blank test. The cumulative displacement was always greater than the blank. The displacement was1.5times to twice times weighed than blank. Water quality of sludge dewatering experiment was within wastewater discharge standard. And residual water can be discharged directly. |
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