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CN-121990737-A - Method for synchronously realizing deep dehydration of sludge and recovery of carbon source

CN121990737ACN 121990737 ACN121990737 ACN 121990737ACN-121990737-A

Abstract

The invention discloses a method for synchronously realizing deep dehydration of sludge and recovery of carbon sources. The method comprises the steps of (1) carrying out ultrasonic treatment on sludge by utilizing an ultrasonic dispersion system to destroy a sludge floc structure and release intracellular organic matters, (2) carrying out a selective experiment of filter cloth meshes according to sludge characteristics to determine optimal filtering parameters, (3) sending the sludge subjected to ultrasonic treatment into a filter type centrifuge with a nestable filter screen to carry out mud-water separation, and (4) respectively collecting dehydrated sludge and filtrate in a filter type centrifuge filter cylinder to realize sludge reduction and carbon source recovery. The invention uses ultrasonic to disperse and crush cells, can remove interstitial water among cells and bound water in cells, adopts a filter centrifuge, can separate most organic matters and inorganic matters in the sludge after ultrasonic treatment, and synchronously realizes deep dehydration of the sludge and effective recovery of carbon sources.

Inventors

  • LIN QINGYUAN
  • JIANG DONG
  • FEI XIAOXIN

Assignees

  • 中冶华天工程技术有限公司

Dates

Publication Date
20260508
Application Date
20260209

Claims (7)

  1. 1. The method for synchronously realizing deep dehydration of sludge and recovery of carbon sources is characterized by comprising the following steps: (1) Carrying out ultrasonic treatment on the sludge by utilizing an ultrasonic dispersion system so as to destroy the sludge floc structure and release intracellular organic matters; (2) Carrying out a selective experiment of the mesh number of the filter cloth according to the sludge characteristics, and determining optimal filtering parameters; (3) Sending the sludge subjected to ultrasonic treatment into a filter type centrifuge with a nestable filter screen for sludge-water separation; (4) And respectively collecting dehydrated sludge and filtrate in the filter type centrifuge filter cylinder to realize sludge reduction and carbon source recovery.
  2. 2. The method for synchronously realizing deep dehydration of sludge and recovery of carbon source according to claim 1, wherein the sludge is residual activated sludge or anaerobic fermentation sludge generated in the biological sewage treatment process, and the initial water content is 90% -99.9%.
  3. 3. The method for synchronously realizing deep dehydration of sludge and recovery of carbon source according to claim 1, wherein the sonic energy density of the ultrasonic treatment in the step (1) is 100-1000W/L, the ultrasonic frequency is 20-30 kHz, and the ultrasonic time is not more than 30 minutes.
  4. 4. The method for synchronously realizing deep dehydration of sludge and recovery of carbon sources according to claim 1, wherein the mesh number of the filter cloth in the step (2) is 200-800 meshes, and the filter cloth is made of acid-alkali resistant synthetic fibers and is suitable for filtering high-humidity sludge.
  5. 5. The method for synchronously realizing deep dehydration of sludge and recovery of carbon sources according to claim 1, wherein the centrifugal speed of the filter centrifuge in the step (3) is 500-5000 r/min, the centrifugal time is not more than 30 minutes, and the filtrate is continuously discharged during the centrifugation.
  6. 6. The method for synchronously realizing deep dehydration of sludge and recovery of carbon source according to claim 1, wherein the filtrate is rich in soluble organic matters (SCOD) and can be reused as carbon source for biological denitrification and dephosphorization process of sewage.
  7. 7. The method for synchronously realizing deep dehydration of sludge and recovery of carbon sources according to claim 1, wherein the water content of the dehydrated sludge can be reduced to below 60 percent to meet the requirements of subsequent incineration, composting or landfill disposal.

Description

Method for synchronously realizing deep dehydration of sludge and recovery of carbon source Technical Field The invention relates to a method for synchronously realizing deep dehydration of sludge and recovery of carbon sources. Background The water in the sludge is free water, interstitial water, adsorbed water and bound water. The free water can be removed mechanically, but in municipal sludge industry, the sludge is added with flocculant and contains a large amount of viscous organic matters (the main components are proteins, polysaccharides and the like) outside cells, so that the water content of the sludge is still more than 75% even though the sludge is subjected to mechanical dehydration methods such as a plate-and-frame filter press, centrifugation and the like, and the sludge is difficult to further treat and utilize. The latter three kinds of water are difficult to remove by a conventional dehydration method, so that sludge is difficult to dehydrate and the energy consumption is high. In order to make the water content of the sludge lower than 60%, a sludge heat drying method is generally adopted at present, but the method has higher cost and is not suitable for a large-scale sewage treatment plant. In addition, the sludge contains rich carbon sources, and the sludge can be recycled to a sewage treatment plant to be used as a supplementary carbon source after being properly treated, but in the current common carbon source recycling method, namely, after the sludge is pretreated by a physical or chemical method, anaerobic fermentation is carried out, and then the sludge is recycled to the sewage treatment plant, and the obtained carbon sources have low concentration of organic matters and inorganic matters, so that the carbon sources are insufficient and even the sludge expansion phenomenon can occur when the carbon sources are recycled to the sewage treatment plant. Disclosure of Invention In order to overcome the defects, the invention aims to provide a method for synchronously realizing deep dehydration of sludge and recovery of carbon sources. In order to achieve the above purpose, the method for synchronously realizing deep dehydration of sludge and recovery of carbon sources comprises the following steps: (1) Carrying out ultrasonic treatment on the sludge by utilizing an ultrasonic dispersion system so as to destroy the sludge floc structure and release intracellular organic matters; (2) Carrying out a selective experiment of the mesh number of the filter cloth according to the sludge characteristics, and determining optimal filtering parameters; (3) Sending the sludge subjected to ultrasonic treatment into a filter type centrifuge with a nestable filter screen for sludge-water separation; (4) And respectively collecting dehydrated sludge and filtrate in the filter type centrifuge filter cylinder to realize sludge reduction and carbon source recovery. Further, the sludge is residual activated sludge or anaerobic fermentation sludge generated in the sewage biological treatment process, and the initial water content is 90% -99.9%. Further, the sonic energy density of the ultrasonic treatment in the step (1) is 100-1000W/L, the ultrasonic frequency is 20-30 kHz, and the ultrasonic time is not more than 30 minutes. Further, in the step (2), the mesh number of the filter cloth is 200-800 meshes, and the filter cloth is made of acid-base resistant synthetic fibers and is suitable for filtering high-humidity sludge. Further, the centrifugal speed of the filter type centrifugal machine in the step (3) is 500-5000 r/min, the centrifugal time is not more than 30 minutes, and the filtrate is continuously discharged in the centrifugal process. Further, the filtrate is rich in soluble organic matters (SCOD) and can be used as a carbon source for the sewage biological denitrification and dephosphorization process. Further, the water content of the dewatered sludge can be reduced to below 60%, so that the requirements of subsequent incineration, composting or landfill disposal are met. The technology of the invention has the following advantages: 1) The filter type centrifuge can separate most of organic matters from inorganic matters in the sludge after the ultrasonic treatment, and the organic matters in the sludge can reduce the dehydration efficiency, so that the sludge with the removed organic matters can achieve good dehydration effect. Compared with the traditional mechanical dehydration and centrifugal dehydration, the water content of the dehydrated sludge is still up to 70% -80%, the method can obviously achieve higher dehydration efficiency, and the water content of the sludge can be lower than 50%. 2) The f value of organic matters in the sludge filtrate treated by the filter type centrifugal machine can reach 0.7, compared with the original sludge, the organic matters in the sludge are increased, most of inorganic matters are trapped, and the organic matters can be recycled to a sewage treatm