Loading...

Acceleration of Anaerobic Stabilization of Organic Solid Waste &Treatment of Following Sewage by a Biologic Tower

Hassanian, Hamed | 2009

815 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 39726 (09)
  4. University: Sharif University of Technology
  5. Department: Civil Engineering
  6. Advisor(s): Hashemian, Jamaleddin; Nazari Alavi, Alireza
  7. Abstract:
  8. In this project, function of anaerobic digestion of organic waste in liquid phase and treating the following sewage in biologic tower(trickling filter) has been investigated in an experimental process. Solid waste were supplied from sharif university restaurant and after weighting and classification is added to tanks which filled by 40% sludge and 60% water. For controlling the function of biologic tower, a control reactor were used. Retention time for digestion of solid waste is 40 day. First solid loading was 500g and 75g organic waste in main & control reactor equal to 5(kg solid waste)/( m^3.reactor.day) 1.3(kg TS)/( m^3.reactor.day) and were doubled in second loading. It seems that digestion tank didn’t have capability of reception of doubling loading. Digestion will cause in reduction of pH & increase in soluble COD. Anaerobic tank content after passing a filter is transferred to a biologic tower and then discharged again to the digestion tank. Biologic tower enhances the rate of digestion by adjusting the pH of digestion reactor, reduction of soluble COD, increase and solid content. Tank content can be used as fertilizer. Solid output of main reactor in loading of 1(kg solid waste)/( day) (260(g dried solidwaste)/( day)) is 95g/( day), with concerning that humidity of solidwaste is 70%, output solids were loosed 95% of initial volume and 25% of initial dried volume which is very good in compare with other biological treatment of solidwaste. Humidity reserve of dried digested output is equal to compost sample and is 12% more than agricultural soil. Nutrient content (C,N,P) of digested material states that digested material is suitable in respect to current fertilizers. COD increase of sample with digested output is about 20% less than similar sample with animal fertilizer. It will justify discharge of liquid content of digestion tank to agricultural farm as a liquid fertilizer with COD of more than discharge standard(200 mg/lit). Application of biologic tower can reduce 50% of soluble COD of anaerobic digestion tank and increased pH of anaerobic tank, so it can improve the capacity of anaerobic digestion tank to accept more solid waste loading. By adding the organic waste to tank, salinity of tank will increase gradually. Salinity can act as an obstacle parameter and reduces efficiency of COD removal in biologic tower. At the end of the loading period to reform the salinity, tank's water was replaced with fresh water and salinity of tank were reduced from 17 ppt to 4.5 ppt. So again efficiency of COD removal were increased. Input of 1 kg solidwaste averagely will increase 0.831 ppt of salinity.

  9. Keywords:
  10. Anaerobic Digestion ; Chemical Oxygen Demand (COD) ; PH ; Organic Solid Waste ; Biological Tower (Trickling Filter) ; Fertilizer

 Digital Object List

 Bookmark

No TOC