Organic Resource Processing
What to do with food waste and compostable packaging?
Of course avoiding it in the first place is key, but what to do with the rest of the ‘organic’ materials that your event may generate?
Most events have people eating, and for those events that must use disposable plates, cups and cutlery, if you’re doing your purchasing right, then there is a likelihood you’re also going to have a fair volume of compostable serviceware too.
You want to keep that out of landfill. Why? Buried organic waste when it ‘rots’ creates methane, which is a potent greenhouse gas, between 25 and 75 more powerful than CO2! Tonnes of biodegradable waste lays rotting, sending up methane, when it could have become fertiliser if processed through a composting facility. Let’s not let your biodegradable waste end up in landfill.
The only real way to prevent the negative impacts of sending biodegradable waste to landfill (methane emissions) is to stop it from entering in the first place.
If you will create a lot of compostable resources (food, disposable serviceware, green waste) then be prepared to actually collect these materials and send for composting.
What does this mean for events?
If you will create a lot of compostable resources (food, disposable service-ware, green waste) then be prepared to actually collect these materials and send for composting.
- Estimate the likely volume of compostable materials that will be part of your waste stream and determine if collecting it separately is warranted.
- Determine if processing facilities exist locally and enquire what type of materials they will accept.
- Investigate the claims of materials to understand the difference between ‘degradable’, ‘biodegradable’, and ‘compostable’, so that you can cross check that with local facilities.
- Determine if at-event logistics will allow successful collection of compostable materials
There are many options for your event’s compostable materials to end up! It will completely depend, of course, on what facilities are available.
Compostable material could be treated at a windrow composting facility or commercial-sized worm farm, often located on the outskirts of town where farms are located.
There could also be an in-vessel composting facility turning compostable waste into high-grade compost in about a week. An alternative for food waste may be an anaerobic digestion facility, serving the food waste needs of the catering industry.
Commercial composting facilities use fast processing in-vessel systems or traditional windrows or heaps located outdoors.
Uncontaminated compostable waste can be processed at commercial in-vessel compost facilities and come out as usable life-giving compost within a week or two.
If you’re sending your waste to a commercial in-vessel composting facility a near-perfect level of uncontaminated compostable waste will be needed.
Do what you can to prevent the wrong thing from mixing in with the compostable waste.
Another great solution for compostable waste is the humble worm. If you are lucky enough to have a commercial-sized worm farm in your vicinity, arrange for your compostable waste to go to them. Better still, your venue might have a worm farm on-site like the terrific Adelaide Convention Centre. Watch the video above of a prison that has an onsite worm composting set up. Venues can do this too!
Anaerobic Digestion and Biogas
Anaerobic digestions is composting biodegradable material in the absence of oxygen. The result is biogas (a mixture of methane & CO2) used to generate electricity and heat, and digestate the solids/liquids left at the end of the decomposition process.
This digestate can be used as agricultural fertiliser or additionally treated in a traditional composting operation.
AD is composting biodegradable material in the absence of oxygen. The result is biogas (a mixture of methane and CO2) used to generate electricity and heat, and digestate (the solids/liquids left at the end of the decomposition process). This digestate may be used as agricultural fertiliser or additionally treated in a traditional composting operation.
So what of compost itself? What is it good for?
Compost adds organic matter to soil, improving plant growth, offering a natural fertiliser. Modern agricultural techniques deplete organic carbon levels in soil, making it less stable, less able to hold water and contributing to erosion and salinity. Compost also has a wonderful benefit of sequestering carbon, keeping it in the soil, where eventually it will be taken up by plants and return to the natural carbon cycle.
So what are your options?
- Windrow or heap composting
- In-vessel small batch composting (like the one in the video below)
- Large-scale in-vessel composting
- Worm farm
- Soldier fly larvae (yes!)
- Anaerobic digestion
You could have a composting set-up at the event or venue or send to a commercial composting facility.
For smaller venues you could have a more domestic-style composting set up, like a tumbler, or even a system similar to a Bokashi Bin where you use beneficial bacteria.
At a few events I’ve even heard of the food waste being gathered and sent to one of the stallholder’s pigs! A great solution. If you have your own compost heap at home that can take a modest quantity of food waste, why not take it home? Sure, there are some slight council rules being violated, but I won’t tell anyone if you don’t!
Small batch in-vessel composting
In-Vessel systems can be small batch such as in this video.
Some events, such as DGTL in Amsterdam have such a machine in their food court, processing the day’s food waste from festival-goers into compost in a 24 hour cycle.
Depending on available land or facilities, venues and campuses could have their own onsite composting systems. The video above shows this university campus’ onsite solution.
For outdoor events you may be able to adopt a more DIY approach to processing compostable resources.
Some events such as Bonnaroo in the USA or Woodford Folk Festival in Australia, have set up systems to compost their own waste on-site. Examples also exist of venues and hotels having large sized worm farms to deal with kitchen waste, such as Adelaide Convention Centre and Excel in London.
For smaller events you may be able to team up with the local community gardens to take your compostable waste. They may also be interested, in exchange for tickets, promotion or a donation, in staffing the bins. They could do up beautifully decorated bins, and to remove the waste, along with composting it. This could be a great greening story for both of you. Stomp Festival in Newcastle, NSW did just this. Bins were given to Figtree Community Garden whose volunteers painted them up. They were then brought to the event, filled with compostable waste, and returned to the gardens for composting and use there.
Climate and Ocean impact of Composting?
Watch the video above to see the connection between healthy soils and healthy seas. By composting you are preventing this biodegradable waste from rotting in landfill and creating methane a potent greenhouse gas. You are also preventing the use of fossil fuel based and chemical fertiliser. Reducing climate impact is good for the ocean and reducing chemical fertiliser prevent contaminated run off into the ocean from agricultural land!