Microbiological Evaluation of the Effectiveness of Sewage Sludge Sanitization with Solar Drying Technology

Table 5

Results of statistical analysis of obtained microbiological data.

Cycle	Bacteria	Regression equation	𝑅^2 (%)	Theoretical time of survival (days)	Elimination rate (log MPN × day^−1)
Sludge from carriers placed on the turner frame
Summer	Salmonella Senftenberg W775	𝑦=−0.075𝑥+7.57	61.11	104A,a,c,j	0.08A,G,a,e,f,j,n
	Escherichia coli	𝑦=−0.157𝑥+7.43	88.93	47^B,a,c,j	0.16^B,D,a,d,j,n
	Enterococci	𝑦=−0.089𝑥+7.68	68.95	89^A,D,a,d,j	0.09^A,D,G,c,e,f,g
Winter	Salmonella Senftenberg W775	𝑦=−0.103𝑥+9.48	77.69	94^A,E,a,e,j,g	0.10^A,D,G,I,b,e,h
	Escherichia coli	𝑦=−0.106𝑥+7.85	65.97	75^A,B,b,d,f,g	0.11^A,D,G,I,b,e,h
	Enterococci	𝑦=0.012𝑥+8.46	6.26	—	0.01^C,E,a,e,i,m
Sludge from carriers placed on turner shovels
Summer	Salmonella Senftenberg W775	𝑦=−0.192𝑥+7.72	96.57	40^B,a,c,j	0.19^B,F,a,e,j,n
	Escherichia coli	𝑦=−0.139𝑥+7.51	74.77	55^B,D,E,c,h,k	0.14^A,D,F,H,I,b,d,i,k,l
	Enterococci	𝑦=−0.050𝑥+8.23	38.99	168^C,F,G,a,c,f,h	0.05^E,G,f,j,k
Winter	Salmonella Senftenberg W775	𝑦=−0.096𝑥+9.29	70.46	98^A,a,c,j	0.10^A,D,G,I,e,l,m
	Escherichia coli	𝑦=−0.111𝑥+7.78	77.03	71^A,B,E,b,d,h,l,k	0.11^A,D,G,I,c,e,l,o
	Enterococci	𝑦=0.030𝑥+8.01	36.67	—	−0.03^C,a,e,j,l,n
Sludge from carriers placed in a sludge pile
Summer	Salmonella Senftenberg W775	𝑦=−0.070𝑥+7.28	91.29	104^A,a,c,j	0.07^A,G,a,e,j,n
	Escherichia coli	𝑦=−0.187𝑥+7.84	92.09	42^B,a,c,j	0.19^B,H,a,e,j,n
	Enterococci	𝑦=−0.165𝑥+8.57	79.27	52^B,D,c,e,k	0.17^B,I,a,g,k,n
Winter	Salmonella Senftenberg W775	𝑦=−0.107𝑥+9.60	81.05	90^A,D,a,f,i,j,k	0.11^A,D,G,I,c,e,l,p
	Escherichia coli	𝑦=0.051𝑥+7.37	50.05	148^C,F,G,g,j,k	0.05^E,G,g,k,n
	Enterococci	𝑦=0.035𝑥+7.99	40.77	—	0.04^C,a,g,h,j,k,o,p,m

^{A, B, C,…}Highly statistically significant differences (𝑃 ≤ 0.01).
^{a, b, c,…}Statistically significant differences (𝑃 ≤ 0.05).