Showing papers on "Hydraulic retention time published in 1981"

TL;DR: In this article, the efficiency of two denitrifying sludges enriched at 5 and 20°C were compared using methanol as an electron donor, and the low temperature sludge appeared to be biochemically and microbiologically stable to temperature changes within the range 0-17°C, the latter temperature being close to the limit for maintaining the psychrophilic characteristics of the sludge.

TL;DR: The essential advantage of the new model lies in its simpler and faster applicability, and the difference in dry matter content of the wasted sludge and that remaining in the activated sludge stage are now taken into account as well, facilitating a more exact calculation of the elimination.

TL;DR: In this paper, a 2-stage system was developed for the treatment of dairy shed wastewater, which consisted of an unmixed uninsulated anaerobic tank of 5-10 days hydraulic residence time followed by a stone media trickling filter over which the waste was circulated for periods of 1-3 days.