From wastewater treatment to water resource recovery: Environmental and economic impacts of full-scale implementation

Going beyond conventional wastewater treatment plants within circular bioeconomy concept – a sustainability assessment study

“…The impact from the fermentation process attributes to the background emissions induced by the production of chemicals and minerals needed for the preparation of modified-dAMS. As can be observed in Figure 5, the substitution of natural gas (the marginal source of biomethane production in 2030 in agreement with Elyasi et al (2021) and Faragò et al (2021)) caused the highest saving in the resource scarcity damage category, accounting for 93% of the total saving. The co-digestion of biopulp and sludge results in higher methane yield (Zha et al 2020).…”

“…Accordingly, biomass-wood chip and biomass-wood pellet were chosen as marginal qualified sources for the centralized heating system. Regarding the biomethane produced, natural gas was considered to be substituted, which is in line with the Danish energy outlook as shown in the recent studies (Elyasi et al 2021;Faragò et al 2021). Considering conventional protein sources for animal feeds, the most preferred proteinaceous feeds that are imported to Denmark are rapeseed, sunflower, and soybean meal.…”

“…The supply of plant's electricity demand from excess wind power and the upgrading of all biogas into biomethane for further injection to gas grids instead of combusting in CHP have higher environmental benefits (Faragò et al 2021). However, the results achieved herein demonstrated that supplying the plant's heat demand from the grid would result in significant environmental burdens.…”

“…As discussed in the previous sub-section, the impacts associated with the fermentation process originate from the consumption of chemicals and electricity demand. Faragò et al (2021) reported that the utilization of electricity and chemicals for P recovery from sludge ash contributed to the impact category of water eutrophication and subsequently to the ecosystem quality damage category. Following AD and fermentation, the electrolysis process imposed the highest impact on this damage category with a share of 9% (i.e., 0.007 species.yr/FU).…”

Prediction of Mass and Volumetric Flows in a Full-Scale Industrial Waste Treatment Plant

“…When it comes to compounds, samples were taken from 12 locations within the plant (see Fig. 1 for specific tag name): the main liquid influents (PWW 1-3 ) (1,2,3), after primary clarifier (PRI-M Over ) (7), after the pre-acidification tank (PAT Eff ) (9), after the anaerobic granular sludge reactor (AGSR Eff ) (13), after the activated sludge reactors (ASR Eff ) (20), secondary clarifier over and underflow (SEC Over , SEC WAS , SEC RAS ) (24,23,17) and dewatering over and underflow (DEW Under, DEW Over ) (36,16). Additional measurements were conducted to characterize other critical streams: primary underflow (PRIM under ) (8), spent biomass stream (SBM) (29), quicklime (IT CaO ) (31), output inactivation tank (IT Eff , IT Eff-Ext ) (32,33).…”