It is, however, music to the ears of environmentalists to hear that last year 10.5 million pounds of recycled plastic made its way not into landfills, but into 184 million new HP inkjet cartridges. That work won HP the 2008 Dan Eberhardt Environmental Stewardship Award from the Society of Plastics Engineers. And those cartridges can, in turn, be recycled indefinitely, thanks to, of all things, plastic water bottles and a formulation developed by Montreal’s Lavergne Group.
Plastics recycling is complicated by the fact that there are many types of the material, with different chemical and physical properties, and they can’t be mixed.
A bit of contamination can ruin a whole batch. This meant the development of equipment and processes to identify each cartridge that arrives for recycling to ensure the material remains unsullied.
Ken Turner, HP’s recycling operations manager for the imaging and printing group’s Americas supply chain, led journalists on a tour of the company’s 80,000 sq. ft. inkjet recycling facility (there’s a separate plant in Virginia for LaserJet cartridges), which recently doubled in size thanks to the success of the program. He explained that it is the just first of several stops before a new inkjet cartridge emerges. Outputs from this plant include not only PET plastic, but foam, metal and aluminum foil; all but the foam is recycled.
HP’s Planet Partners program, which offers multiple free ways to return used cartridges, is the vehicle supplying the inputs. They arrive individually in the single envelopes that used to be supplied with new cartridges (now discontinued to cut waste), in envelopes holding several cartridges, and in larger quantities from corporations and from recycling partner Staples, who now collects expired cartridges from its customers. Bulk collection cartons are also available to anyone on request, with return shipping prepaid, from www.hp.com/recycle (a potential value-add for environmentally-minded resellers).
Getting from cartridge to reusable material is a complex and noisy process. First the envelopes and the cartridges must be separated, either by slashing the envelopes to shreds with high-speed knives or by a newer wringer process in which the cartridges are popped out of their bags like seeds from a grape as the bags are pulled through rollers.
The odd bit of foreign material ends up in those recycling bags too – we saw a bin containing old cell phones, batteries and a dead BlackBerry that had emerged instead of cartridges.
Those items are disposed of as hazardous waste, says Turner, since their composition is unknown (refilled cartridges must be treated in the same manner).
All cartridges now must be sorted to ensure different types of plastic don’t get mixed. They pass through a machine that both x-rays them and takes a colour photo; comparing those images against those in a database allows the equipment to separate the cartridges.
Next, each type of cartridge is separately chopped into pieces.
Those pieces are not all plastic, however, so must be further processed. First they move onto a vibrating table that orients foam and flex to make it easier to remove. Then they’re dropped into water, where the lighter materials are skimmed off, the plastic is cleaned of ink residue, then centrifuged dry and passed by magnets to extract bits of metal.
The metal is recycled, and foam is safely disposed of (it can’t yet be recycled).
The inky water goes through an evaporator; the water is re-used, and the ink sludge is sent for safe disposal.
Plastic is shipped to a plant in Indiana for further cleaning, then to Lavergne’s Montreal facility where it is mixed with the aforementioned plastic water bottles and various additives to produce fresh plastic for a new generation of inkjet cartridges.
Which will, in the fullness of time, end up back here in Music City.