A technological and economic analysis of vacuum-assisted fermentation to augment enhanced biological phosphorus removal at full-scale.

IntensiCarb® represents a vacuum-driven intensification technology with applicability in fermentation or anaerobic digestion. Implementation of this technology in fermentation facilitates a 50% reduction in process volume while concurrently enhancing the yield of volatile fatty acids (VFAs) for advantageous utilization such as carbon source for enhanced biological phosphorus removal (EBPR). An analysis was conducted to assess the process performance and life-cycle costs of IntensiCarb in comparison to chemical addition and conventional fermentation methodologies for Total Phosphorus (TP) removal.

Making waves: Riding the densification wave from current understanding to advancement.

Densification is a novel intensification strategy with the potential to improve treatment capacity within existing continuous-flow (CF) water resource recovery facilities at low capital and operating costs and at relatively small particle sizes compared to typical aerobic granular sludge (AGS) systems. To achieve densification, biological selection principles derived from selector design and AGS concepts have been coupled with physical selection via hydrocyclones at full-scale CF facilities to promote the growth and retention of granules. This combination lowers the sludge volume index (SVI) through superior sludge settling and paves the way for optimized nutrient removal and energy efficiency in low dissolved oxygen conditions.

An investigation into the optimal granular sludge size for simultaneous nitrogen and phosphate removal.

An aerobic granular sludge (AGS) pilot plant fed with a mixture of acetate amended centrate and secondary effluent was used to investigate the optimal granule size range for simultaneous nitrification and denitrification (SND) and ortho-phosphate removal. The anaerobic phase was mixed to understand how AGS will perform if integrated with a continuous flow activated sludge system that cannot feed the influent through the settled sludge bed. Five different granule size fractions were taken from the pilot (operated at DO setpoint of 2mgO/L) and each size was subjected to activity tests in a well-controlled lab-scale AGS reactor at four dissolved oxygen (DO) concentrations of 1, 2, 3, and 4 mgO/L.

Aerobic granular sludge: Impact of size distribution on nitrification capacity.

The relationship between ammonia oxidation rate, nitrifiers population, and modelled aerobic zone volume in different granule sizes was investigated using aerobic granular sludge from a pilot-scale reactor. The pilot was fed with centrate and secondary effluent amended with acetate as the main carbon source. The maximum specific ammonia oxidation rates and community composition of different aerobic granular sludge size fractions were evaluated by batch tests, quantitative PCR, and genomic analysis.