Alessandro di Biase, M.Sc.
Anaerobic moving bed biofilm coupled (AMMBR) with aerobic granular sludge (AGS) technologies treating brewery wastewater
The AMBBR project objectives were, as follows: I) Enhancing the start-up design for laboratory AMMBR; II) Monitoring and testing the performances utilizing AC920 media manufactured by Headworks International with specific protected surface areas of 680 m2 m-3; III) Establishing treatment process guidelines; IV) Testing the reactors with real wastewater; V) Identify the minimum hydraulic retention time (HRT) for small footprint reactor design; VI) Evaluate reactor performance subjected to decreasing temperature. The system were able to remove above 80% of the total chemical oxygen demand (tCOD) with HRT greater than 10h while sCOD removal was more than 80% for HRT greater than 8h. However, the maximum methane yields as soluble COD of 0.36 ± 0.06 m3CH4 kg sCOD-1 was achieved at 18h HRT while 0.34 ± 0.05 m3CH4 kg tCOD-1 as total COD was reached at 6h HRT. The biogas composition was 71.3 ± 2.4 % and 26.2 ± 4.0 % as methane and carbon dioxide, respectively.
On the other hand, the AGS project were conducted in order to achieve the following objectives: I) Startup of AGS reactors; II) Testing and monitoring performances as well as the exocellular polymeric substances (EPS) impact on granulation; III) Establish suitable conditions particularly different organic loading rates (OLRs); IV) Identify the key parameters for brewery wastewater treatment. The granulation startup period was achieved within the first month of operations with above 80% removal as tCOD. The influent as effluent of the AMBBRs was enriched with 100:10:1 as C:N:P ratio. Effluent solids were less than the law limit of 350 mg TSS L-1.
Mengmeng (Alice) Tian M.Sc.
Production of phytase during solid state fermentation using Aspergillus Ficuum in food waste
Municipal solid waste, which is disposed in landfills, generates hazardous contaminated leachate and air emissions. Therefore, it is important to reduce the amount of waste which is sent to the landfill. Solid state fermentation offers a sustainable solution to divert food waste from landfill. Phytic acid is the principal storage form of phosphorus in cereals and oil seeds. It is not a bioavailable source of phosphate for monogastric animals. As such, extra Phosphate in other digestible form has to be added into the animal feed in order to meet the P requirement. If phytase is used in the feed, it can reduce the global total P consumption. This will relief phosphorus demand.
Main purpose of this research: Producing phytase from food waste and optimizing the condition for phytase production
Novelty: All of the previous studies were conducted on agricultural wastes or industrial organic waste. Up-to-date, no research has been reported on using food waste from municipal solid waste as a substrate for solid state fermentation for phytase.
Results and conclusion: 1. Phytase was successfully produced from food waste. 2. The maximum enzyme productivity was observed at 77% moisture content (3.18 U/g ds). 3. The addition of nitrogen sources resulted in great enhancement of enzyme production, especially peptone (7.38 U/g ds).
Cornelia Andreea Badila, MSc.
Evaluation the Performance of Tire Derived Aggregate(TDA) vs Natural aggregate in Septic Field
Septic system is used primarily for single or multi-family residences to provide treatment of household wastewater. It is most commonly used in the rural and remote area. In Canada, currently 20% of household is using septic system as mean of wastewater treatment. Septic systems consist of a septic tank and a septic field. Wastewater solids undergo removal by settling in the septic tank and the resulting clarified effluent flows out of the septic tank into the septic field and surrounding soil. The role of the septic field is to provide good distribution of the liquid wastewater to the surrounding soil where the majority of treatment occurs. In most septic system installations, natural aggregate (stone) is used to distribute the wastewater to the surrounding soil and support biological growth. Studies conducted in the US have shown that TDA, with similar geometry to natural aggregate and high stability, is an excellent candidate for replacement of natural aggregate in septic field. The objective of this proposal is to evaluate TDA as a replacement for nature aggregate in the Canadian context.
This proposed project will be last for 24 months. The project’s test site will be located in Ashern, Manitoba. An existing leachate field will be evacuated and four leaching trenches will be constructed. Two trenches will be tested with TDA and the other two trenches will be tested with natural aggregate. A series of experiments will be conducted to study 1) the TDA integrity during the service period; 2) Hydraulic performance of TDA, i.e. the permeability of the surrounding soils; 3) chemical constituents and concentration that are leaching from TDA. This study will provide valuable information on the suitability of TDA to act as a substitute for rock aggregate in a leach field in Canada.
Elsie Jordaan, PhD Biosystems Engineering Technology status Lab scale Summary
Identification of microbial indicator groups for early warning of anaerobic digester failure using high-throughput sequencing
The overall aim of my research is to identify a specific group or groups within the microbial community of an anaerobic digester that can serve as an early warning indicator of impending failure. Ultimately, these groups could then be specifically targeted during routine analysis of a digester, and a management strategy developed to circumvent failure and maintain steady operation. In order to determine if there is such an identifiable indicator group, a series of ‘failure prediction’ tests are planned where failure of an anaerobic digester will be induced while the evolution of the microbial community is monitored. In this context, failure of a digester is acidification to the point where the gas production has drastically dropped. Failure in an anaerobic digester is generally caused by toxic, organic, or hydraulic overload. To mimic a natural failure, the organic loading rate of a digester can be increased or the concentration of a specific intermediate substrate, such as acetate or propionate, can be increased. Since the microbial communities of digesters will vary significantly between reactors it is necessary to look for an indicator group that is not so specific that it is only present in a few digesters. The classification needs to be specific yet wide enough to encompass a group that is usually present in a range of digesters, yet rises to prominence only during an imminent reactor crises. Since the desired indicator group could be at any level or proportion of the microbial community, it would be best to widen the search as much as possible. A high-throughput sequencing approach using the 16S rDNA gene as a target group will allow for comprehensive coverage and characterization of the microbial community to the genus level, while the Illumina platform provides access to organisms with a low relative abundance.
Ian Moran, University of Manitoba Environmental Engineering
Comparison of fouling mechanisms and behaviour of four nanofiltration membranes for Stephenfield Regional Water Treatment Plant
A major issue for the dual membrane plants is NF fouling – the undesirable accumulation of material (foulant) retained on the surface of a membrane. Over operational time, the foulant layer acts as an inhibitor of permeate flux and can significantly increase operational costs for a water treatment plant (WTP). The extent of membrane fouling is determined by the interaction of the particular membrane with the dissolved or suspended material in the feed water. Therefore, the selection of an appropriate membrane to minimize the effects of membrane fouling is imperative for efficient WTP output and the successful removal of undesirable material. Physical and chemical analyses were carried out on four different membranes (DOW FILMTEC NF90-400/34i, DOW FILMTEC NF270-400/34i, DOW FILMTEC BW30XFR-400/34i, DOW FILMTEC XFRLE-400/34i) to determine the membrane most suitable for installation in the development of the Stephenfield WTP in southern Manitoba. Post-microfiltration water from the Stephenfield WTP was run in cross flow across each membrane at different operational time steps (1, 4, 12, 24, 48 hours). The DOW FILMTEC NF270-400/34i exhibited the highest initial permeate flux, the smallest retained mass of foulant after 24 hours and was the only membrane to leave enough hardness and alkalinity so as to avoid post-treatment for those properties and, as such, was chosen for pilot scale testing. Under operating conditions, it was observed that the DOW FILMTEC NF270-400/34i did not remove a sufficient amount of manganese. Further investigation for membrane selection is needed.