The increasing use of single-use (i.e., disposable) systems (SUS) in biopharmaceutical manufacturing is causing manufacturers and users to consider whether recycling is a viable alternative to landfill disposal or incineration. While the overall environmental footprint of disposables has already been shown to be lower than multiple-use systems in some cases, due to factors such as savings in cleaning water, industry members are taking a close look at disposal options that can further improve the sustainability of SUS.
Many facilities send their SUS-waste to landfill and others incinerate, either in their own facilities or offsite, and even use cogeneration facilities to produce power, say SUS suppliers. Cogeneration (i.e., waste-to-energy) is considered more environmentally preferable than traditional incineration. Plastics components have a high energy value and can be burned, for example, in cement kilns, which require large amounts of energy and do use alternative fuels, such as plastics or vehicle tires.
More recently, SUS suppliers and users have been moving toward recycling, which has become a more viable proposal now that the volumes of plastics used in SUS have increased, comments Jeffery Lee Craig, global director for business development and marketing at ATMI LifeSciences. A life-cycle analysis of SUS showed that recycling does reduce the carbon footprint, even over cogeneration, comments Johanna Jobin, sustainability manager at EMD Millipore.
Recycling can, as expected, be used for nonhazardous waste, such as in upstream media and buffer preparation. Downstream components that have come into contact with biohazards, such as viruses, must go through a kill cycle, such as an autoclave, before disposal, notes Ken Baker, CEO of New Age Industries. Once decontaminated, however, these components can also be recycled, says Jobin.
Both thermoplastic (e.g., polyethylene, nylon) and thermoset (e.g., silicone) components can be recycled although in different ways. Thermoplastics can be melted and reformed into new plastic parts like pallets and plastic lumber. Silicone, however, can be recracked and used in caulk, for example, says Baker.
A big challenge for recycling has been the lack of infrastructure for collecting and disassembly, says Jobin. EMD Millipore began a pilot program this past year to identify the requirements for successful recycling and to better understand the logistics needed to develop a recycling infrastructure. EMD Millipore partnered with a third-party recycler, which collects and disassembles waste and recycles the plastic materials. Because many of the systems are made out of multiple plastic components that are difficult to separate, disassembly is currently done by hand, says Jobin. Although some of the bags and films are multiple layers (e.g., polyethylene, nylon, and ethylene vinyl alcohol copolymer), this has not presented a problem in the current recycling system. Other components, such as woven filter membranes attached to plastic frames, are a challenge to the disassembling and recycling process. EMD Millipore, however, has been taking the lessons learned from these challenges and applying them in the company’s design for sustainability program. “We have learned more about types of materials to use for easier recycling and how to design assemblies for easier disassembly at the end of life,” says Jobin. EMD Millipore’s pilot recycling program has had positive results so far, and the company hopes to scale up from the current East-Coast US operation to the rest of the US, and perhaps eventually to Europe. “The end-of-life aspect of SUS is particularly visible to the company’s employees and management and plays a role in its acceptance,” comments Jobin. Recycling also impacts each customer’s own sustainability programs. EMD Millipore estimates that one of its customers could recycle 11,000 lbs of SUS waste per month, which would boost its annual recycling rate by 5-7%.
At the recent Bio-Process Systems Alliance (BPSA) International Single-Use Summit in Washington DC, BPSA members agreed that recycling is important because it can have a significant, positive impact on sustainability. Now that volumes of SUS have increased and are expected to continue to grow, the industry needs to develop recycling as an option.