Effect of sludge age on the digestion of the liquor obtained after endogenous enzymatic hydrolysis

  1. Marañón Maison, María Elena 1
  2. Negral Álvarez, Luis 13
  3. Fernández Nava, Yolanda 2
  4. Castrillón Peláez, Leonor 2
  5. Ormaechea Menéndez, Pedro 1
  1. 1 Universidad de Oviedo

    Universidad de Oviedo

    Oviedo, España

    ROR https://ror.org/006gksa02

  2. 2 Escuela Politécnica Superior de Ingenieros (Gijón)
  3. 3 Universidad Politécnica de Cartagena

    Universidad Politécnica de Cartagena

    Cartagena, España

    ROR https://ror.org/02k5kx966

4th European Conference on Sludge Management 26th-27th May 2014, Izmir (Turkey)

Year of publication: 2014

Type: Conference paper


Inverted Phase Fermentation is a method for thickening sewage sludge that results in a clarified phase beneath a thickened fraction. An increased hydrolysis rate is obtained in both phases. The liquid phase or liquor was digested in UASB reactors. The optimum methane yield was obtained for hydraulic retention time of 1 day (0.32 m3 CH4/kg VS, 2.31 m3 CH4/m3reactor day). When this liquor was co-digested with 1% (v/v) crude glycerin, the optimum methane yield was obtained when operating at hydraulic retention time of 2 days (0.67 m3 CH4/kg VS, 2.76 m3CH4/m3reactor day). Co-digestion of the liquor with crude glycerin not only improved specific methane yield, but also organic matter biodegradation (up to 89% total COD and up to 76% VS removal).