Metropolitan WWTP
Minneapolis / St.Paul, U.S.A.
Client: Metropolitan Council Environmental Services (MCES).
EnviroSim was retained as a process specialist with Brown & Caldwell and Reid Crowther for the implementation of biological nutrient removal at the Metro WWTP (240 mgd). This principally involved application of the BioWin process simulator in the process selection and design stage, in a one-year process proving project, and in wastewater characterization studies. The existing step-feed extended aeration system has been converted to a nitrogen and biological phosphorus system without necessitating the construction of new tankage.

Regional WWTPs
Minneapolis / St.Paul, U.S.A.
Client: Metropolitan Council Environmental Services (MCES).
EnviroSim, in association with Brown & Caldwell, conducted an evaluation of the Seneca, Blue Lake, Hastings and Stillwater WWTPs (95, 95, 7 and 13 ML/d). This involved calibration of the BioWin process simulator to one year of operating data, and plant capacity assessment in (a) the as-designed fully-aerated operating mode, and (b) with plant modifications to incorporate biological nutrient removal.

Chelmsford WWTP
Ontario, Canada
Client: Regional Municipality of Sudbury, Ontario
EnviroSim completed a demonstration of nitrification and biological nutrient removal at the Chelmsford WWTP on behalf of Sudbury, Environment Canada and the Ontario MOE. The objective of the study was to evaluate plant start-up and performance in Ontario at low temperature conditions. Activities included wastewater characterization and simulation for process design and technical assistance to process operations and the development and direction of experiments to produce information on the performance and economic feasibility of the process in this application.

Christies Beach and Glenelg WWTPs
Adelaide, Australia
Client: South Australia Water Corporation, Australia.
EnviroSim completed a full-scale demonstration of a plant nitrification/denitrification upgrade on a 7.5 ML/d module at the Christies Beach WWTP in Adelaide. This involved the application of free-floating plastic media for enhancing nitrification performance, using technology demonstrated at the Waterdown WWTP (Ontario). As a result of this study, a free-floating media upgrade was implemented on the full Christies Beach (30 ML/d) and Glenelg (60 ML/d) treatment plants in Adelaide. The overall objective is to attain year-round nitrification (with substantial denitrification) at an SRT of 2-3 days, thereby increasing current plant capacity but obviating the need for new construction.

Czajka WWTP
Warsaw, Poland
Client: City of Warsaw, Poland.
The 200 ML/d Czajka WWTP treats flow from east of the River Vistula in Warsaw. The City is considering expansion to 530 ML/d by including flow from west of the river. Bench-scale testing in SBRs and monitoring of the existing plant was conducted over one year. EnviroSim has (a) conducted a calibration study to provide wastewater characterization and nitrification rate data, and (b) developed pre-designs for three process options for the plant upgrade and expansion.

North Shore WWTP
Auckland, New Zealand
Client: North Shore City Council, New Zealand.
EnviroSim was commissioned by Woodward Clyde NZ to review the process design of an expansion to the North Shore WWTP. The new plant has been designed to treat 54 ML/d in a Modified Ludzack Ettinger (MLE) configuration with year-round nitrification and denitrification.