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      Sewage heat recovery system used in Harbin, China
      

      
Source: Xinhua|
Published: 2021-10-24

      

      
      
             
      
        
      
        
      
          
        
      
      
      
      
      
      

      
      
      
      
                        
      A sewage heat recovery system is being used in Harbin, China to heat homes and supply hot water.
      
 
            
      
      

      

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