The application of natural tundra wetlands for municipal wastewater treatment is an option to meet upcoming federal wastewater systems effluent regulations for Canada’s Far North. A treatment performance assessment with physical, hydraulic and biogeochemical contextual data was conducted on the wetland treatment area of Coral Harbour, Nunavut. A modified Tanks-In-Series model was used to model treatment kinetics. The study showed seasonal variability in treatment performance and hydraulic characteristics. A decrease in vegetation diversity and deposition of organic detritus was observed in high effluent loading areas. Effective reduction in effluent concentrations was observed. Dilution from watershed contributions accounted for much of the reductions observed. The importance of the determination of the hydraulic residence time, field delineation of the wetted area, and delineation of the watershed was demonstrated. First order rate coefficients determined suggested that the selection of the lowest percentiles from literature of southern treatment wetlands is conservative in this case.

Vertical flow constructed wetlands (VF CWs) are becoming increasingly popular for onsite wastewater treatment due to their high oxygen transfer capacity and high nitrification rates. However, there are still some question marks regarding (1) how the treatment performance of VF CWs is affected by design and operational parameters, and (2) the treatment processes happening inside the wetland bed as the wastewater percolates through. In this study, we investigated the effects of filter media (coarse sand or fine gravel), dosing regime (hourly with 4 mm or bi-hourly with 8 mm) and plant presence (with or without Phragmites australis) on the  treatment performance and concentration depth profiles of pollutant removal in six pilot-scale VF CWs treating primary treated domestic wastewater. Grab samples of wastewater were collected every 2-3 weeks during 5 months and analyzed for organic matter, suspended solids, nitrogen and E. coli. We found that sand beds performed better than gravel beds for removal of all pollutants except total nitrogen, although for long term operation gravel may be less susceptible to clogging. The overall treatment performance was not affected by different dosing regimes, but the concentration depth profiles showed that smaller and more frequent doses led to more pollutant removal in the upper part of the beds. The presence of plants was moderately important for the removal of ammonium, but had no effect on other pollutants.

Para o tratamento de esgoto sanitário foi desenvolvido e estudado um reator UASB (Upflow Anaerobic Sludge Blanket), associado com unidade de filtração. O estudo se iniciou pela operação do reator UASB durante 642 dias, onde a fase líquida afluente e efluente foi monitorada. Em seguida uma unidade de filtração foi acoplada ao reator UASB e foram avaliados as características de filtração, o desempenho do tratamento e a eficiência do processo de limpeza química de três filtros. Os materiais poliméricos utilizados como filtros foram o polipropileno, o poliéster e o geossintético de poliéster, com diâmetro médio de poros de um mícron (1μm). As características de filtração avaliadas foram o fluxo do permeado e os mecanismos de obstrução de cada material polimérico (resistência à filtração: total, do material, da camada de biossólidos e de entupimento). O desempenho global do sistema de tratamento foi avaliado em termos de remoção de demanda química de oxigênio (DQO) e de sólidos suspensos totais (SST). Para recuperação dos filtros foi utilizada primeiramente a limpeza química com solução ácida (ácido clorídrico-HCl) e em série a limpeza com solução alcalina (hipoclorito de sódio e hidróxido de sódio- NaOCl e NaOH). Dentre os três materiais poliméricos utilizados verificou-se que, o geossintético (poliéster) foi o filtro que apresentou melhores características de filtração e desempenho global, ou seja, com este material a resistência da camada foi predominante (obstrução é reversível), a concentração de sólidos suspensos totais do permeado estabilizou em 25 mg/L e a eficiência média global de remoção da demanda química de oxigênio (DQO) foi de 78%. Dentre os procedimentos de limpeza química utilizada nos três filtros, verificou-se que a solução ácida (HCl) aplicada em série com a solução alcalina (NaOCl e NaOH) apresentou maior eficiência que a limpeza somente com a solução ácida (recuperação do fluxo inicial do permeado acima de 90%). / An anaerobic reactor (UASB – Upflow Anaerobic Sludge Blanket) coupled to a filtration unit for the treatment of domestic sewage was developed and studied. The study began by operating the UASB reactor for 642 days, during which time the influent and effluent liquid phase were monitored. The filtration unit was then coupled to the UASB reactor and the filtration characteristics, the performance of the treatment, and the efficiency of the cleaning process of three polymeric filters were evaluated. The polymeric materials used for the filters were polypropylene, polyester and geosynthetic polyester, all with an average pore size of one micron (1μm). The filtration characteristics evaluated were the permeate flux and the fouling mechanisms (total filtration resistance of the material and the cake, and clogging) during filtration. The system’s overall performance was evaluated in terms of chemical oxygen demand (COD) and removal of total suspended solids (TSS). The filters were cleaned chemically, first with an acid solution (HCl), followed by alkaline solutions (NaOH and NaOCl) applied in series. A comparison of the three filtering materials indicated that the geosynthetic material (polyester) possessed the best overall characteristics of filtration and performance. In other words, i.e., cake resistance (reversible fouling) predominated with this material, the concentration of total suspended solids (TSS) in the permeate stabilized at 25 mg/L, and the overall removal efficiency of chemical oxygen demand (COD) was 78%. Of the various chemical cleaning procedures tested on the three polymeric filters, the acid (HCl) and alkaline solutions (NaOH and NaOCl) applied in series provided more efficient flux recovery (over 90% of the initial permeate) than chemical cleaning only with acid (HCl).

Para o tratamento de esgoto sanitário foi desenvolvido e estudado um reator UASB (Upflow Anaerobic Sludge Blanket), associado com unidade de filtração. O estudo se iniciou pela operação do reator UASB durante 642 dias, onde a fase líquida afluente e efluente foi monitorada. Em seguida uma unidade de filtração foi acoplada ao reator UASB e foram avaliados as características de filtração, o desempenho do tratamento e a eficiência do processo de limpeza química de três filtros. Os materiais poliméricos utilizados como filtros foram o polipropileno, o poliéster e o geossintético de poliéster, com diâmetro médio de poros de um mícron (1μm). As características de filtração avaliadas foram o fluxo do permeado e os mecanismos de obstrução de cada material polimérico (resistência à filtração: total, do material, da camada de biossólidos e de entupimento). O desempenho global do sistema de tratamento foi avaliado em termos de remoção de demanda química de oxigênio (DQO) e de sólidos suspensos totais (SST). Para recuperação dos filtros foi utilizada primeiramente a limpeza química com solução ácida (ácido clorídrico-HCl) e em série a limpeza com solução alcalina (hipoclorito de sódio e hidróxido de sódio- NaOCl e NaOH). Dentre os três materiais poliméricos utilizados verificou-se que, o geossintético (poliéster) foi o filtro que apresentou melhores características de filtração e desempenho global, ou seja, com este material a resistência da camada foi predominante (obstrução é reversível), a concentração de sólidos suspensos totais do permeado estabilizou em 25 mg/L e a eficiência média global de remoção da demanda química de oxigênio (DQO) foi de 78%. Dentre os procedimentos de limpeza química utilizada nos três filtros, verificou-se que a solução ácida (HCl) aplicada em série com a solução alcalina (NaOCl e NaOH) apresentou maior eficiência que a limpeza somente com a solução ácida (recuperação do fluxo inicial do permeado acima de 90%). / An anaerobic reactor (UASB – Upflow Anaerobic Sludge Blanket) coupled to a filtration unit for the treatment of domestic sewage was developed and studied. The study began by operating the UASB reactor for 642 days, during which time the influent and effluent liquid phase were monitored. The filtration unit was then coupled to the UASB reactor and the filtration characteristics, the performance of the treatment, and the efficiency of the cleaning process of three polymeric filters were evaluated. The polymeric materials used for the filters were polypropylene, polyester and geosynthetic polyester, all with an average pore size of one micron (1μm). The filtration characteristics evaluated were the permeate flux and the fouling mechanisms (total filtration resistance of the material and the cake, and clogging) during filtration. The system’s overall performance was evaluated in terms of chemical oxygen demand (COD) and removal of total suspended solids (TSS). The filters were cleaned chemically, first with an acid solution (HCl), followed by alkaline solutions (NaOH and NaOCl) applied in series. A comparison of the three filtering materials indicated that the geosynthetic material (polyester) possessed the best overall characteristics of filtration and performance. In other words, i.e., cake resistance (reversible fouling) predominated with this material, the concentration of total suspended solids (TSS) in the permeate stabilized at 25 mg/L, and the overall removal efficiency of chemical oxygen demand (COD) was 78%. Of the various chemical cleaning procedures tested on the three polymeric filters, the acid (HCl) and alkaline solutions (NaOH and NaOCl) applied in series provided more efficient flux recovery (over 90% of the initial permeate) than chemical cleaning only with acid (HCl).

Black soldier fly larvae (BSFL) waste treatment is becoming a more sought-after organic waste treatment since it produces larvae for animal feed as well as fertilizer, the need for prediction and optimization of treatment performance increases. This study aims to predict biomass conversion efficiency (BCE) for waste going into treatment, using only the nutritional data from other studies as it could give a good performance estimation while using available data. First, macronutrient fractions, based on a normalized total weight of volatile solids (VS), were calculated from nutritional data of other studies and of this present study.  Using the results, coordinates of these samples were calculated and put on the ternary plot, revealing trends for different macronutrient compositions. To validate these trends, selected nutrient compositions were created as waste mixtures containing fish, bread and vegetable waste and then treated by BSFL. After treatment, BCE and waste reduction in both VS and wet weight basis were noted.  The results showed that a composition high in carbohydrate and low in fat content is favorable for a high BCE value while protein content remained similar across all treatments and only seemed to slightly increase BCE. Treatment A5 held the highest BCE%VS (32.6 ± 3.5) with a composition of 73%VS carbohydrates, 19%VS protein and 8%VS fat and control treatment (A0) with no fish waste held the highest BCE%WW  (21.2 ± 1.8).   When comparing with the results of the other studies used to make the trends in the ternary plot, predictions of BCE were more accurate for a composition  of  70%VS carbohydrates, 20-25%VS protein and < 8%VS fat and also for compositions with similar waste substrates, as their percental changes were similar. This suggests that it is possible to predict high BCE  values from nutritional data in a ternary plot and could be of use when optimizing larval production. / Fluglarvskompostering med den amerikanska vapensflugan (Hermetia illucens) är en avfallsbehandling för organiskt avfall som producerar larver och gödselmedel som kan används som djurfoder respektive gödselmedel.  Många studier har undersökt hur makronäringsämnen påverkar larvproduktion eller behandlingseffektiviteten och kommit till olika resultat. I dagens läge skulle det underlätta om man kunde uppskatta den högsta möjliga effektiviteten baserat på data om avfallet som redan finns utan att behöva gå igenom en längre studie först. Den här studien har som syfte att undersöka om det är möjligt att förutspå biomassomvandlings-effektivitet (BCE) från makronäringsdata tagen från andra studier i ett triangulärt diagram. I denna studie användes studierna av Lopes et al., (2020) och Isibika et al., (2021) som basdata i triangulär diagrammet.  För att validera det trender som sågs i det triangulära diagrammet utfördes tester på valda kompositioner beståendes av ansjovis, bröd och grönsaksavfall med fluglarvkompostering. För att kunna applicera makronäringsämnernas data till triangulär diagrammet, beräknades mängden protein, kolhydrater och fett som en andel av den totala mängden glödförlust (VS).  Efter behandling beräknades BCE på våtvikt (WW) och VS basis.  Resultaten tyder på att en avfallskomposition med hög halt kolhydrater och låg halt fett (70%VS kolhydrater, 20–25%VS protein and <8%VS fett) bidrog till ett högt BCE värde, där proteinhalten var snarlik i alla behandlingar och verkade ha ett litet bidrag till ett högt BCE värde. Behandlingen A5 hade det högsta BCE%VS värdet (32.6 ± 3.5) med en komposition av 73%VS kolhydrater, 19%VS protein och 8%VS fett och kontroll behandlingen A0 (utan ansjovis avfall) hade högst BCE%WW värde (21.2 ± 1.8).   Vid jämförelse mellan de andra studierna och resultaten, var uppskattningar av BCE mer precisa för en komposition med ca 70%VS kolhydrater, 20–25%VS protein and <8%VS fett och för uppskattningar baserad på data från rapporter med liknande avfallssubstrat, då deras procentuella förändringar var liknande varandra. Detta stärker hypotesen att det är möjligt att kunna förutspå högt BCE värde med hjälp av näringsdata från avfallet och skulle kunna användas för att optimera av larvproduktion.