Les Aliments Bari Inc. processes potato products, along with other vegetable products, which are sold to specialty stores and restaurants throughout Quebec and central Canada.
Les Aliments Bari Inc.’s processing plant in Saint-Léonard-d’Aston, Quebec, Canada, needed a new wastewater treatment solution. In the past, wastewater was stored in large tanks on-site that was then applied on local farmland when weather permitted. However, because the company wanted to expand production, it became challenging to find enough land to apply the wastewater. Odor had also become a concern.
Les Aliments Bari Inc. also required a wastewater treatment option that was capable of meeting very strict effluent limits. Several technologies were considered, including anaerobic treatment, activated sludge technology, and membrane bioreactor (MBR). MBR technology was investigated on-site at pilot scale.
The ADI® MBR was ultimately chosen over other wastewater treatment technologies, as it offered the lowest capital cost, a compact footprint, and was most capable of consistently meeting the strict effluent requirements.
ADI Systems was contracted by Les Aliments Bari Inc. to provide engineering design and supply/installation of a modular membrane tank for the MBR wastewater treatment system. The modular membrane tank includes an equipment shelter which houses the permeate pump, membrane scour aeration blower, and cleaning system, as well as instrumentation and controls. The modular tank and shelter was fabricated, piped, and wired and then shipped to Les Aliments Bari Inc.’s processing plant as a complete package unit.
This wastewater treatment system consists of a 1,000 m3 (264,172 gal) cast-in-place concrete preaeration tank and a 37 m3 (9,774 gal) modular package membrane tank. The system is complete with influent and effluent pumps, aeration blowers, process piping and valving, the modular membrane tank with auxiliary equipment, and a sludge dewatering system.
An insulated floating modular cover system was installed on the preaeration tank to retain heat during the winter months—an important consideration given the cold Quebec winters and the fact that the average wastewater temperature at Les Aliments Bari Inc. is only 62.6°F (17°C).
The MBR system successfully treats a very high-strength wastewater with 19,000 mg/l chemical oxygen demand (COD), 10,000 mg/l biochemical oxygen demand (BOD), and 4,000 mg/l total suspended solids (TSS) concentrations at a flow rate of 96 m3/d (25,300 gpd).
Les Aliments Bari Inc.’s production plant consistently complies with strict effluent requirements set forth by the Province of Quebec for BOD (< 10 mg/l), TSS (< 10 mg/l), and total phosphorus (< 1 mg/l). The floating insulated cover, together with exothermic heat generation from aerobic biological activity, has allowed the preaeration tank temperature to be maintained at > 75°F (> 20°C) during the winter months.