Reading guidance：With the development of world economy, municipal sewage amount get more and more. Accordingly, sludge amount gets more and more. Processing method of residual sludge mainly in open dumps, landfills, se

   With the development of world economy, municipal sewage amount get more and more. Accordingly, sludge amount gets more and more. Processing method of residual sludge mainly in open dumps, landfills, sea and other means, the cost of the characteristics of these methods is low, but easy to cause two pollution; sludge incineration technology of sludge treatment and disposal of excess sludge is the most thorough method, it can make all the organic carbonization, kill pathogens, can minimize sludge the volume, but the disadvantage of high energy consumption. Using ultrasonic method of sludge pretreatment, reduce emissions, improve sludge TN, the removal rate of TP, shorten the time and reduce the consumption of sludge, foam increase gas production, this method is a kind of physical method, the two will not cause pollution to the environment. Ultrasonic sludge treatment technology development in foreign countries have relatively mature, has achieved the application of engineering products. The domestic research on this aspect is still in the exploratory stage, there is no industrial device set off, There are not many research papers in this area.
1. Ultrasonic sludge disposal equipment
  In recent years, ultrasonic disposal method is gradually applied to sewage treatment plants and shows great effects. The ultrasonic sludge treatment equipment company in Germany, the basic configuration is 5 high-power ultrasonic transducer, the power of each transducer is 1kW, a 5kW intelligent ultrasonic power. This device can meet the daily processing 50 thousand cubic meters of city sewage treatment plant, a single set of equipment every day to handle sludge 30m3/d, can be adjusted according to how much the amount of sludge treatment the configuration of this device, such as the treatment of less than 30m3/d can reduce the number of transducers is greater than 30m3/d, whereas treatment can increase the number of equipment. America's ultrasonic sludge treatment equipment, equipment configuration and the German products are basically the same, the difference is not the same transducer working mode, respectively. Surface acoustic radiation and the radial acoustic radiation.
 2. Composition of ultrasonic disposal equipment
   Ultrasonic sludge treatment system by high power ultrasonic transducer, high power ultrasonic intelligent power, reactor and water recovery unit, the main components such as shown in Figure 3. Ultrasonic transducers convert electrical energy into mechanical energy effect in sewage sludge and sludge crushing; ultrasonic wave power supply by the MCU or DSP generates a signal, after the power amplifier, the matching network input to the transducer, the transducer provides excitation signal and constantly monitoring the running state of the transducer; water extraction unit control sludge into the volume; reactor is ultrasonic sludge treatment of container in the container fully cavitation treatment the sludge.
 3. Mechanism of ultrasonic sludge disposal method
  Application of ultrasonic biological sludge in the sewage treatment equipment produced in the process of treatment (activated sludge), the principle is the sludge generated resonance cavitation bubble under the action of ultrasonic wave, and expansion in the micro environment of cavitation bubble generated at high temperature and high pressure (at 5000 500bar), the final resonance implosion strength produced by water jet the flow form of hydraulic shear force is huge, achieve great damage on the microbial cell wall structure of the sludge flocs and sludge, the cytoplasm and enzyme dissolution from the cell (Fig. 4), when it is used as catalyst and nutritional supplements flows back to the biochemical system, effectively complement the biochemical stage required carbon source, biochemical system degradation efficiency and greatly improved, more and more pollutants will be converted into carbon dioxide and water, the sludge emissions reduction.
 4. Function of ultrasonic sludge disposal equipment 
  Functions and characteristics of ultrasonic disposal method
  A. reduce the sludge digestion time up to 60% of the original, so that can reduce the sludge tank volume, reduce construction costs;
  B. increase the bio gas production 30-45%, bio gas power generation can be added to the sewage treatment part of the electricity;
  C. Ultrasonic treatment can improve the sludge dehydration rate, reduce the use of 15-45% flocculant, reduce the residual sludge as high as 30%;
  D. After ultrasonic treatment of sludge, the microbial cell wall were punctured and release large amounts of the enzyme, accelerated the process of anaerobic digestion, and can effectively kill and control of sludge in the various pathogens;
E. after ultrasonic treatment sludge can be TN, TP to provide a carbon source to remove, reduce the input of carbon sources, improve the removal rate of TP, tn;
F. the sewage treatment plant can reduce the sludge treatment cost after ultrasonic treatment.
 
 
 

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