Biogas potential and methanogenic community shift in in-situ anaerobic sewage sludge digestion with food waste leachate additions

Applied Biological Chemistry

Table 1 Outline of target biogasification facilities

Facility	Treatment materials^c	Type of digestion	Mixing ratio (SS:FW(L))	Design capacity of digester (ton/day)	Volume of digester (m³)	HRT (day)	Organic loading rate (kg _VS/m³ day)	pH
SD^a	Sewage sludge (rWWTSS, eWWTSS)	Mesophilic, single stage	–	932	21,000	28	1.38	7.9 (± 0.1)
CD^b1	Sewage sludge (rWWTSS, eWWTSS), food waste leachate	Mesophilic, single stage	0.965:0.035	7680	179,988	39	0.84	8.2 (± 0.1)
CD2	Sewage sludge (rWWTSS), food waste leachate	Mesophilic, single stage	0.87:0.13	4205	82,776	27	1.40	8.1 (± 0.3)
CD3	Sewage sludge (rWWTSS), food waste	Mesophilic, single stage	0.37:0.63	430	14,000	23	2.88	8.0 (± 0.3)

^aSD Anaerobic digestion facility treating sewage sludge only
^bCD: Combined anaerobic digestion facility treating sewage sludge and food waste (leachate)
^crWWTSS Raw wastewater treatment sewage sludge, eWWTSS Excess wastewater treatment sewage sludge