Kinetics of anaerobic degradation of screened dairy manure by upflow fixed bed digesters: Effect of natural zeolite addition

Abstract

The effect of the hydraulic retention time (HRT) on the performance of two up-flow anaerobic fixed bed digesters (UFAFBDs) packed with waste tire rubber (D1) and waste tire rubber and zeolite (D2) as micro-organism immobilization supports was studied. It was found that a first-order kinetic model described well the experimental results obtained. The kinetic constants for COD, BOD5, total solids (TS) and volatile solids (VS) removal were determined to be higher in digester D2 than in digester D1 or control. Specifically, they were 0.28 +/- 0.01, 0.32 +/- 0.02, 0.16 +/- 0.01 and 0.24 +/- 0.01 d(- 1) respectively for D1 and 0.33 +/- 0.02, 0.40 +/- 0.02, 0.21 +/- 0.01 and 0.28 +/- 0.01 d(- 1) respectively for D2. This was significant at the 95% confidence level. In addition, the first-order model was also adequate for assessing the effect of the HRT on the removal efficiency and methane production. Maximum methane yield and the first-order constant for methane production were determined and the results obtained were comparable with those obtained by other authors but operating at higher HRTs. Maximum methane yields and the kinetic constant for methane production were 11.1% and 29.4% higher in digester D2 than in D1.

Removal of Sulphate and Manganese on Synthetic Wastewater in Sulphate Reducing Bioreactor Using Indonesian Natural Zeolite

“…During bioreactor operation, the population density of SRB increased approximately 5 times from 5 days to 9 days operation. This raising altered of cross-feeding, co-metabolism, interspecies hydrogen and proton transfer between SRB cells [36][37]. Furthermore, its condition may further stimulate the growth of micro colonies which effect on the increasing of their activity for removing sulphate and manganese.…”

Sustainable Agro-Food Industrial Wastewater Treatment Using High Rate Anaerobic Process

“…The investigation showed that the growth yield (Y G ), specific biomass decay (b), maximum specific biomass growth rate (μ max ), saturation constant (K s ) and critical retention time (Θ c ) were in the range of 0.990 g VSS g Fuzzato et al [26] used simplified first-order kinetics for modeling a mesophilic anaerobic sequencing batch biofilm reactor (ASBBR) treating lipid-rich wastewater. Nikolaeva et al [40] also observed that a first-order kinetic model described the experimental results obtained for the upflow fixed bed digesters treating dairy manure well. In addition, they also concluded that the first-order model was adequate for assessing the effect of HRT on the removal efficiency and methane production.…”

“…The upflow fixed bed reactors or upflow anaerobic filter (UAF) is one of the earlier designs, and its characteristics are well defined [3,22,40]. The UAF is a relatively simple technology; and in engineering terms, it is not as complex as fluidized bed reactors, and in biological terms, it does not require the formation of a granular sludge, a prerequisite for the UASB reactor, which is usually very difficult to maintain.…”

“…Nikolaeva et al [40] used waste tire rubber and zeolite as microorganism immobilization supports; Fia et al [6] used blast furnace cinders, polyurethane foam and crushed stone as the supporting materials with porosities of 53%, 95% and 48%, respectively. Other materials that have been utilized for the adhesion of biomass included brick ballasts [44], Raschig rings (1.2 cm diameter ×1.2 cm) [45], low and high-density polyethylene media [3,22,35,41], polypropylene pall rings [46], non-woven disks [47], porous polyurethane foam [48] and modified porphyritic andesite (WRS) as ammonium adsorbent and bed material [49].…”

Bipolar effects of settling time on active biomass retention in anaerobic sequencing batch reactors digesting flushed dairy manure

“…As pointed by Wilkie et al (2004), flushed dairy manure poses challenges to conventional high temperature anaerobic digesters because of the large volume of flushing water that must be heated. To address this issue, fixed-film digesters with submerged high specific surface area media were introduced to retain active biomass through bacterial attachment (Nikolaeva et al, 2009;Umana et al, 2008;Vartak et al, 1996;Wilkie et al, 2004). Nevertheless, fixed-film was classified as an inappropriate process for dairy manure anaerobic digestion due to its vulnerability to media clogging (Burke, 2001).…”