Wastewater treatment byproducts, or biosolids, are used as a key ingredient in the GMWC composting system.
Treatment of sludge at the WWTF involves conditioning with liquid lime, use of high-speed centrifuges for dewatering, followed by the addition of dry lime.
Upon arrival at the Composting Facility, it is mixed with green waste consisting of bark (from sawmills), ground forestry waste, wood chips and other green waste.
The initial mix produces 40 windrows, on average annually, that are 50 m long on the composting pad. Windrows spend a minimum of eight weeks on the active aerated pad and are turned over twice. The windrows are covered with a breathable cover during the initial phases and can reach temperatures of more than 70° Celsius. The windrows are then moved and grouped into lots of three initial windrows on the curing pad where they are conditioned and left to compost at a slower rate while cooling down. The complete process takes one year. Consequently, one year's production will be available for use in the following year.
Processing and product usage in the present year involves screening of the previous year's stockpiles (lots) for use by the general public, landscapers and local municipalities. The public was allowed to pick up compost free of charge from the self-loading bins. Product was sold to landscapers and is provided to the area municipalities for their horticultural activities and various land improvement/development projects.
2020 Historical Data Compost Operational Data (tonnes)
Compost Clientele 2015 2016 2017 2018 2019 2020 Public pick-up 4,000 5,750 5,000 5,300 5,765 6,592 Commercial users 960 1,000 1,000 650 1,156 1,862 City of Moncton 800 40 130 100 186 220 City of Dieppe 200 60 60 10 60 -- Town of Riverview 96 150 60 100 166 54 Other Municipalities 190 193 Community projects (Donations) 400 200 200 160 339 14 Trials/tests/promotional 400 200 150 1,500 695 -- Miscellaneous/TransAqua 400 200 200 500 205 20 Annual compost output totals 7,256 7,600 7,400 8,320 8,773 9,315 Compost Lots created 13 17 13 13 13 13 End of Season Inventory 1,750 100 3,000 3,840 2,336 501 |