Inside the recycled material recovery facility on Sheffield Rd., where City of Ottawa residents' blue box contents are sorted and processed. Photos by Jon Connor.
Ever wondered what happens to your blue box contents once they've been picked up?
The container plant operated by Cascades on Sheffield Rd. processes 83 tonnes of blue box recyclables every day from 42 collection vehicles. Here's how that happens along the way:
Main conveyor feed: Material is dumped onto a large conveyor belt. An optical sensor stops the belt when material piles up at the top.
Backscraping or metering drum: Controls the amount of material entering the system, spreads material out and tears bags open.
Pre-sorting: Bags are opened. Large garbage is pulled off. Scrap metal and bulky plastics are sorted for recycling.
Ballistic separator: Carries flat items like paper, cardboard and plastic bags up to a sorting station where fibre is separated from film. Missed containers are thrown back into the line. Three-dimensional items fall down the paddles onto a conveyor that takes them into the next sorting area. Glass is broken by the paddles and sent down.
Drum magnet and cyclone: The conveyor carries material up and drops it over a spinning magnet, which captured steel items and sends them to a separate conveyor. The rest of the material falls on a fine screen, where small items, mostly glass, fall through and are conveyed to a cyclone that vacuums lightweight material away from the glass.
Optical sorters: The remaining material is spread out over speed belts and sent to two optical sorters. These sorters use infrared light to read material types, and air jets to blow the targeted objects to the desired place.
Optical sorter 1 directs polycoats down the first chute, and #1 plastics upward to the third chute. The remaining material falls through the middle chute to continue to optical sorter 2.
Optical sorter 2 directs #2 plastics down the first chute, and #3-7 plastics upward to the third chute. The remaining material falls through the middle chute to continue to manual sort line.
Manual sort line: Here, people pull off items that were missed by the mechanical sorting systems and throw them into the proper bunkers.
Eddy current separator: Uses a magnetic rotor to create eddy currents in the aluminum cans. The aluminum is propelled forward while gravity lets the remaining material drop onto the residual belt.
Residual belt: Leads to optical sorter 3, which redirects missed materials back into the system, while residual material drops into the residual bunker.
Baler: When the bunker for any targeted material fills up, it is transported to a baler and compacted into bales for shipping. The bales weigh between 500 and 1,000 kg, depending on the material.
Quality control: A quality control person at the end of each sort pulls out unwanted material and sends it back into the system.
Top "bin sins"
The worst contaminants found in City of Ottawa residents' blue boxes are:
- Household hazardous waste (oil, gas, pesticides, herbicides) in full or partly full containers or aerosol cans
- Propane and helium cylinders
- Plastic bags and films (grocery bags, milk and chip bags, cling wrap, cellophane wrapping). Please don't place your recyclables in bags.
- Garden items (tools, hoses, garden edging, lawn furniture, pool liners)
- Small appliances (toasters, broilers, microwaves) and power tools (drills, saws)
- Kitchenware (plates, cups and other ceramics, pots, pans)
- Random metal and plastic (car parts, children’s toys)
- Paper and cardboard, which belongs in the black box. However, some cardboard-like food and beverage containers, such as milk and ice cream cartons, as well as frozen juice cans, do belong in the blue bin.
- Organic materials (food, plants), which belong in the green bin
The worst contaminants in black boxes are:
- Plastic bags and plastic film (grocery bags, milk and chip bags, cling wrap, cellophane wrapping). Please don't place your recyclables in bags.
- Blue bin materials, especially gable-top containers (milk and juice cartons), aseptic containers (Tetra Paks), cans and beverage containers, which all belong in the blue box
- Metal automotive parts (rotors, calipers, pads)
- General waste
Ottawa's blue box stream has a contamination rate of about 20 percent, compared to only about 4 percent for black boxes.
If you're not sure whether an item belongs in your blue box, black box, green bin or the garbage, you can look it up in the City of Ottawa's Waste Explorer.