Anaerobic biodegradability of Category 2 animal by-products: Methane potential and inoculum source

Abstract

Category 2 animal by-products that need to be sterilized with steam pressure according Regulation (EC) 1774/2002 are studied. In this work, 2 sets of experiments were performed in mesophilic conditions: (i) biomethane potential determination testing 0.5%, 2.0% and 5.0% total solids (TS), using sludge from the anaerobic digester of a wastewater treatment plant as inoculum; (ii) biodegradability tests at a constant TS concentration of 2.0% and different inoculum sources (digested sludge from a wastewater treatment plant; granular sludge from an upflow anaerobic sludge blanket reactor; leachate from a municipal solid waste landfill; and sludge from the slaughterhouse wastewater treatment anaerobic lagoon) to select the more adapted inoculum to the substrate in study. The higher specific methane production was of 317 mL CH(4)g(-1) VS(substrate) for 2.0% TS. The digested sludge from the wastewater treatment plant led to the lowest lag-phase period and higher methane potential rate.

Methane potential and metagenomics of wastewater sludge and a methane‐producing landfill solid sample as microbial inocula for anaerobic digestion of food waste

“…Even though less CH 4 was produced, biogas quality was slightly higher from sludge than from the landfill solid sample (56% and 47% CH 4 , respectively), suggesting that both samples have potential as microbial inocula and are comparable at optimal I:S ratios. Landfill leachate has been used to test agroindustrial waste biodegradability with productivities of 50-314 mL CH 4 g −1 VS. 13,14 Although comparable at the highest value to our results, landfill leachate might possess concentrated amounts of heavy metals that could compromise the use of the digestate as a by-product. The combined inoculum exhibited satisfactory results for all performance criteria evaluated; in particular, gas composition up to 62.3% CH 4 and COD removal efficiency up to 90.5%.…”

“…Another interesting inoculum, associated with municipal waste treatment, is landfill that intrinsically possesses methanogenic activity. Landfill leachate has been used with satisfactory results; its alkaline nature can alleviate organic acid accumulation during digestion . However, start‐up time and CH 4 production rate from landfill leachate were inferior when compared to wastewater sludge.…”

“…Landfill leachate has been used with satisfactory results; its alkaline nature can alleviate organic acid accumulation during digestion. [12][13][14] However, start-up time and CH 4 production rate from landfill leachate were inferior when compared to wastewater sludge. Nonetheless, landfill solid samples from active CH 4 -producing sites have not been tested, even though they are expected to carry a methanogen community already adapted to municipal waste.…”

Biomethane Potential Test: Influence of Inoculum and the Digestion System

“…Chicken manure, Corn stover [10][11][12][13][14][15][16][17][18][19] Li et al [14] Wastewater treatment plant, slaughterhouse lagoon, municipal solid waste, upflow anaerobic sludge blanket Animal by products 17 Pozdniakova et al [15] Wastewater treatment plant, biogas plant Food waste, wastewater 12-74 Elbeshbishy et al [16] Biogas plants Pig manure, para grass 2-128 Dechrugsa et al [17] Digestate one adapted to turkey manure, one without adaption Turkey manure 1-8 Chamy and Ramos [18] Wastewater treatment plant, biogas plant, biowaste plant…”

Experimental and Modelling Approach of Biogas Production by Anaerobic Digestion of Agricultural Resources

“…Previous studies reported the existence of three characteristic zones during cumulative methane production process as a result of different biomasses anaerobic digestion [24]. A lag zone corresponding to the period before gas generation started can be noticed at the beginning of the digestion process.…”