A moving-bed biofilm reactor has been developed, where the biofilm grows on small, free-floating plastic elements with a large surface area and a density slightly less than 1.0 g/cm3. Nitrification of preprecipitated wastewater in a once-through system and raw wastewater
in a recycled system with predenitrification has been studied in a pilot plant with an active, specific biofilm surface area of approximately 310 m2/m3. Maximum nitrification rates under comparable operating conditions were 20% to 25% higher with preprecipitated wastewater
in the once-through system than with raw wastewater in the recycled system. A temperature coefficient of = 1.09 was found. However, under oxygen-limited conditions, the apparent temperature effect was insignificant in the temperature range from 7 to 18°C because of increased
dissolved oxygen levels at low temperatures. At 10°C volumetric nitrification rates from 300 to 400 g NH4-N/m3·d can be expected.
Water Environment Research® (WER®) publishes peer-reviewed research papers, research notes, state-of-the-art and critical reviews on original, fundamental and applied research in all scientific and technical areas related to water quality, pollution control, and management. An annual Literature Review provides a review of published books and articles on water quality topics from the previous year. Published as: Sewage Works Journal, 1928 - 1949; Sewage and Industrial Wastes, 1950 - 1959; Journal Water Pollution Control Federation, 1959 - Oct 1989; Research Journal Water Pollution Control Federation, Nov 1989 - 1991; Water Environment Research, 1992 - present.