Cultivation, granulation and characteristics of anaerobic ammonium-oxidizing sludge in sequencing batch reactor

Abstract

Anaerobic sequencing batch reactor (SBR) was started-up by inoculating the nitrifying activated sludge. After an operation of 72 d, the bioreactor reached at steady state with ammonia and nitrite removal percentages higher than 95%. During operation, the sludge granulated in the reactor. The morphology and internal structure of sludge granules changed conspicuously, the density increased while the color changed from khaki to red. The average granular diameter grew from 1.2 to 3.69 mm, and its settling velocity accelerated from 107.68 to 118.49 m/h. Sludge granulation improved the tolerance to hydraulic shock loading, and reduced sludge washout (TSS < 0.028 g/L). The dominant bacterial communities (filamentous and cocci) in nitrifying activated sludge were replaced by irregular shaped ANAMMOX bacterial species gradually. An increase of ANAMMOX rate was achieved with the increasing granular diameter. SBR is a useful reactor to cultivate ANAMMOX granular sludge, while granular ANAMMOX sludge thus developed can be used as seeding sludge in a pilot-scale or full scale wastewater treatment plant.

The Increasing Interest of ANAMMOX Research in China: Bacteria, Process Development, and Application

“…So, China is the promising and largest market for ANAMMOX waste treatments. In the Netherlands, the first full-scale granular ANAMMOX reactor was commenced at the wastewater treatment plant of Water board Holland se Delta in Rotterdam in 2006 [ 16 , 99 ]. This full-scale ANMMOX treatment plant was the milestone for commercial application of ANAMMOX process.…”

“…High rate is one of the prime objectives for ANAMMOX process. Within the last decades some specialized reactor systems such as sequencing batch reactor (SBR) [ 2 , 16 – 19 ], rotating biological contactor (RBC) [ 18 ], trickling filter [ 19 ], UBF reactor [ 20 ], granular sludge bed reactor [ 21 ], and membrane bioreactor [ 3 , 22 ] have been introduced in both laboratory and full scale to obtain high removal rate, and finally noticed that these reactors played an important role in securing high rate performance for ammonium and nitrite removal. The NRR of conventional nitrogen removal biotechnologies was less than 0.5 kg-N/m 3 /d [ 20 ] while, for ANAMMOX process, it was higher than 5 kg-N/m 3 /d as obtained by a number of researchers using different reactors such as upflow biofilter, upflow anaerobic sludge blanket (UASB) reactor, and gas-lift reactor [ 3 , 23 – 26 ].…”

Identification and quantification of anammox bacteria in eight nitrogen removal reactors

“…The relatively high doubling time (11e20 days) of anammox bacteria was perceived as the major bottleneck for the successful implementation of this process to wastewater treatment. However, within the last decades this problem has been resolved in both laboratory and full scale reactor systems by configurations that enable very efficient sludge retention: sequencing batch reactor (SBR) (Hu et al, 2006;Strous et al, 1998;Kartal et al, 2008,), rotating biological contactor (RBC) (Pynaert et al, 2003,), trickling filter (Schmid et al, 2000), UBF reactor (Jin et al, 2008), granular sludge bed reactor (Zheng et al, 2004) and membrane bioreactor (van der Star et al, 2007;Trigo et al, 2006). Meanwhile, after the start-up the first full scale anammox reactor in Rotterdam (The Netherlands) more than sufficient biomass is available to inoculate new full scale anammox reactors which would reduce the start-up time considerably if one source of seeding sludge could be used for bioreactors treating different types of wastewater (van der Star et al, 2008;Abma et al, 2010).…”