The first North American full scale post aerobic digester (PAD) is successfully operating at the Spokane County Regional Water Reclamation Facility (SCRWRF). The SCRWRF PAD has demonstrated ammonia removals of 90% or above without alkalinity or supplemental carbon addition. When operational controls were optimized for total inorganic nitrogen (TIN) removal, the SCRWRF PAD demonstrated effluent ...

Mixed-microbial assemblages enriched from a septic tank, coastal sediment samples, the digester sludge of a brewery wastewater treatment plant and acidic sulfate soil samples were compared on the basis of growth rate, waste and sulfate reduction rate under sulfate reducing conditions at 30 degrees C. The specific growth rate of various cultures was in the range 0.0013-0.0022 hr(-1). Estimates o...

Introduction Over the past several years there has been significant interest in adopting on-farm manure anaerobic digesters in Ontario. The potential for sustainable energy production, while reducing greenhouse gas (GHG) emissions, mitigating pathogens and odours, and increasing ionized nutrients in the digestate, has made anaerobic digestion an attractive option for manure management. The biog...

This paper describes aerobic digester design for the biodegradation of plant tannins in industrial wastewater. For optimal design, using the criterion of minimal total holding time, some experimental investigations into tannins’ biodegradation rate in industrial wastewater were performed in the first part of this research. The chemical oxygen demand method (COD) was applied to follow the tannin...

A sequencing batch reactor (SBR) was operated to develop denitrifying bacteria that had a mean specific denitrification rate of 0.11 g NO3 -N/gVSS/day. Another system (an anaerobic digester) was operated to generate volatile fatty acids (VFAs) with the effluent concentration being measured to be 5655 ± 876 mg/L as acetic acid. Using the denitrifying biomass developed in the SBR and VFAs generat...

Batch experiment was carried out in a simulated thermophilic aerobic digester to investigate the digestion process of one-stage autothermal thermophilic aerobic digester and to explore the sludge stabilization mechanism. Volatile solids removal was 38.4% at 408 h and 45.0% at 552 h. Chemical oxidation demand, total nitrogen, and ammonia nitrogen in supernatant increased rapidly up to 168 h, and...

The performance of the only dairy manure biogas plant in Cantabria (Northern coast of Spain) was evaluated in terms of liquid-solid separation and anaerobic digestion of the liquid fraction. Screened liquid fraction was satisfactorily treated in a CSTR digester at HRTs from 20 to 10 days with organic loading rates ranging from 2.0 to 4.5 kg VS/(m(3)d). Stable biogas productions from 0.66 to 1.4...

Abstract Household biodigesters are self-mixing anaerobic digesters used mostly in rural areas of developing countries as a reliable source clean cooking energy. For an efficient digestion process, the mixing slurry inside digester is regarded one most important parameters. In this study, three different designs household digesters, namely fixed-dome (GGC 2047 model), plug-flow and prefabricate...

N AN earlier study by the current authors, Gustafson’s model [1] has been applied to the modelling of the kappa number profile of a traditional Kamyr process [2]. In Downflow Lo-Solids cooking [3, 4] the process and flow conditions differ from the ones of the traditional Kamyr. The cooking reactions are, however, the same in both processes and more measurements and control variables are availab...