Moreover, to control reaction conditions (online), the correlation
between SCOD and specific surface on biogas yield
was evaluated (Fig. 5). Specific surface shows a better linear
correlation (R2 ¼ 0.87) with the gas yield in comparison with
SCOD (R2 ¼ 0.2338) and therefore allows a good opportunity to
control ultrasound disintegration and the expected biogas
yield online