Municipal lagoon systems are often challenged with facilitating nitrification. Nitrifying bacteria are responsible for removing ammonia from wastewater. These organisms are generally present in low abundance in lagoon processes for a few reasons: (1) nitrification is an energetically demanding process, and (2) nitrification is easily disrupted by inconsistencies in physical wastewater conditions.
For example, changes in alkalinity and temperature can impair ammonia oxidation. There is limited control over the physical conditions in lagoon systems. Because of these limitations, nitrification is often the rate-limiting reaction in the treatment process.¹
Lagoon systems can be augmented with concentrated cultures of nitrifying bacteria to promote nitrification. The following case study describes the bioaugmentation of a wastewater lagoon network with BioLynceus® ProBiotic Scrubber® II (PBII) to improve ammonia removal.
A 0.2 MGD covered lagoon system in Colorado was experiencing difficulty maintaining a nitrifying biomass. At times, the process basins experienced inconsistent temperature and alkalinity. During the winter months, the wastewater became very cold, halting nitrification. Consistent alkalinity was also not well maintained in the system. These factors, among others not identified, limited nitrification in the lagoons.
City wastewater management wanted to improve nitrification in the treatment process. The facility had effluent ammonia limits to meet and needed to promote ammonia removal. In need of bioaugmentation, the city contacted BioLynceus®.
PBII, a highly diversified consortium of living bacteria abundant in nitrifiers, was added to the lagoon to stimulate the nitrification process. The product was applied over three months: April, May, and June. Wastewater temperatures were above 3°C.
1 Gerardi, M. (2016). Wastewater Bioaugmentation and Biostimulation.
Lancaster, Pennsylvania: DEStech Publications, Inc. Pp. 64.
Figure 1. Pre-treatment (greys) and treatment (blues) influent (Inf.
PT & Inf. T) and effluent (Eff. PT & Eff. T) ammonia concentrations
displayed as measured in the lagoon system over two consecutive
years in April, May, and June.
Figure 2. Monthly percent ammonia removed in the lagoon system
was determined for April, May, and June of the year prior to
treatment (grey) and during treatment (blue). Percent ammonia
removed was calculated by comparing influent and effluent
ammonia concentrations.
Compared with the same period in the previous year, influent ammonia concentrations increased each month, while effluent ammonia concentrations decreased (Figure 1). From April through June of the following year, effluent ammonia concentrations were approximately 96% lower with treatment.
Furthermore, the percentage of ammonia removed during the treatment process increased by 23% in April, 31% in May, and 98% in June (Figure 2).
Augmenting the lagoon system with PBII supported more efficient nitrification and improved effluent quality.
BioLynceus® ProBiotic Scrubber® II helps promote nitrification in wastewater lagoon systems.