Table 6.

Exponential decay coefficients (n = 320 total) for microorganisms in anaerobic digesters based on review of the scientific literature (n = 23 papers). The majority of coefficients (n = 220) represent total coliforms, fecal coliforms, Escherichia coli, Salmonella spp., or Streptococcus spp.

Condition	Decay coefficient (mean ± SD)	n
	d−1
Psychrophilic	0.38 ± 0.28	58
Mesophilic	2.1 ± 3.3	160
Escherichia coli	3.8 ± 4.8	40
Streptococcus spp.	0.65 ± 0.38	16
Laboratory‐scale	2.6 ± 3.8	103
Full‐scale	1.2 ± 1.8	57
Thermophilic	250 ± 1600	102