Sludge settling characterization for the mathematical modelling of sidestream treatment processes

Abstract

More stringent effluent limits, especially with regard to total nitrogen, force wastewater treatment plants to consider sidestream nitrogen removal from digested sludge dewatering liquor which can contain up to 20% of incoming nitrogen load. Deammonification, the most promising biological technology for sidestream nitrogen removal, is based on partial short-cut nitrification and the Anammox process. Both steps of this process are conducted by slowly growing autotrophic bacteria, namely nitrifies and Anammox, which however may form different types of sludge: flocculent and granular, respectively. Nevertheless, ensuring effective sludge separation from treated effluent is crucial for the ability to retain both kinds of slowly growing biomass in the system. This paper presents the principles of sludge settling modelling, the results of a series of column tests conducted on sludge from pilot-scale two-stage deammonification treatment facility, as well as an attempt to estimate settling parameters in order to fit a sedimentation model.

Removal of nickel from Ni(II)-NH3-SO2-CO2-H2O system by electrocoagulation, sedimentation, and filtration processes

“…Also, according to the Takacs´s equation, vf decreased when the sludge concentration tended to zero. Similar behavior of the critical settling velocity was obtained (Figure 11b) [20,47,48]. The unit area (UA / m 2 day t -1 ) was obtained at different solids concentrations (Figure 11c).…”

Automated batch settling column with vibrated rods and evaluation protocol for living waters mud thickening

“…They suggested the calculation of the so called I index determined on the basis of certain parameters of the settling curve for the easy comparison of different settling behaviour of different materials and flocculants. Balbierz and Rucka [4] presented the results of a series of batch settling column tests conducted on sludge from pilot-scale two-stage deammonification treatment facility. They compared the well-known settling models and equations of Vesilind, Takacs et al and Liu et al for their tests.…”