Interaction between temperature and ammonia in mesophilic digesters for animal waste treatment

Microbial Anaerobic Digestion (Bio-Digesters) as an Approach to the Decontamination of Animal Wastes in Pollution Control and the Generation of Renewable Energy

“…Even though the temperature is pivotal in the thermodynamics and kinetics of microbial reactions in methanogenesis, challenges are encountered during treatment at thermophilic temperatures (i.e., 55-65 °C) of ammonium-, urea-and protein-rich biomass materials owing to a high level of free ammonia [108]. Garcia et al [29] noted that at higher temperatures the ratio of free ammonia to total ammonium was much higher; consequently affecting methane generation due to free ammonia inhibition. Nevertheless, an increase in temperature within the mesophilic range relieved the digester system of ammonia toxicity.…”

Influential Parameters on Biomethane Generation in Anaerobic Wastewater Treatment Plants

“…There are various type of waste/wastewater containing high organic nitrogen such as municipal solid waste, young landfill leachate (Yusof et al, 2009), wastewater from seafood processing factories (Guerrero et al, 1997;Gebauer, 2004), animal waste (Garcia & Angenent, 2009) and waste activated sludge (Appels et al, 2008). Therefore, as a results of degradation of the organic nitrogen fraction, high concentration of total ammonium (ammonium (NH 4 + ) plus free ammonia (NH 3 ) in these waste/wastewater is common (Jokela & Rintala, 2003).…”

“…Therefore, as a results of degradation of the organic nitrogen fraction, high concentration of total ammonium (ammonium (NH 4 + ) plus free ammonia (NH 3 ) in these waste/wastewater is common (Jokela & Rintala, 2003). Many studies have shown that free ammonia and not ammonium is responsible to inhibit the methanogenic activity during the anaerobic digestion (Sawayama et al, 2004;Sossa et al, 2004;Calli et al, 2005a;Garcia & Angenent, 2009). In a solution, the ammonia exists in a pH dependent equilibrium between ammonium ion (NH 4 + ) and unionized ammonia or free ammonia (NH 3 ) (see Equation 4).…”

“…Earlier investigation observed that methanogens inhibition strongly occurred at a wide range of total ammonia nitrogen (TAN) concentrations; 1500-3000 mg/L at pH above 7.4 (Hashimoto, 1986); 3300-4100 mg/L at pH 8.1 and temperature 55 o C (Hansen et al, 1998); 6000 mg/L at temperature of 35 o C (Calli et al, 2005a) and 5250 mg/L at temperature of 35 o C (Garcia & Angenent, 2009). The remarkable differences reported in ammonia inhibitive concentration could be ascribed to variations in the TAN concentrations as well as the operating parameters such as pH and temperature (Sung and Liu, 2003).…”

“…It has been shown that the methanogenic activity was higher at higher mesophilic temperature (Masse & Masse, 2001). It was postulated that effects of higher kinetic rate at higher temperature in mesophilic range overwhelmed the free ammonia inhibition (Garcia & Angenent, 2009). However, high ammonia concentrations inhibit methanogenesis more seriously under thermophilic as compared to mesophilic condition (Angelidaki & Ahring, 1993).…”