HOTBIN is diverting food waste
Waldringfield Community Composting scheme is successfully diverting food waste from landfill.
Last weekend we visited our friends at Waldringfield Community Composting to look at the results of the first 3 months of the HOTBIN use.
Everyone was keen to learn how much food waste the 12 households had actually diverted from landfill. The results are in and the weighing scales revealed: 5 Kg/week per household. (It was much higher in the B&B – but they have guests each week which accounted for the 10Kg/week.)
What a marvellous community composting effort.
How does this compare to other customers and the national picture?
Nationally the WRAP figures indicate that 5 Kgs per household per week is the average – I’m sure they will be happy to learn they are normal!
Our own HOTBIN customers survey is less rigorous in terms of weighing exact amounts, but it also indicates HOTBIN users divert around 3-6 Kg of food waste per week from landfill The main difference is between users who choose to really get stuck into what you can hot compost such as cooked food waste and chicken carcass etc. versus those that choose to only compost vegetable peelings.
What does all this mean? Does it make a difference?
If we take all the HOTBIN customers across the UK, the total diversion is still not that huge but as they say from little acorns….
There are 30 million households in the UK, if just 3% actively composted all food waste at home, that would remove 250,000 mt of waste from landfill. That also happens to be about the same amount of waste 10 major anaerobic digestion facilities to be built would process.
Clearly it works in our favour if more people have a HOTBIN but the figures speak for themselves!
What does this mean in terms of garden compost?
Each household is also composting garden waste. A total of 250-500 Kgs of starting material will give 75-150 Kgs of compost which is 5-10 bags of compost a year. That’s saving around £25-50 (maybe £10 more if we include car petrol) over buying from the garden centre.
Are there other benefits?
Yes. There are two huge, almost hidden, benefits of composting:
- More food waste results in more compost. More compost results in more humeric substances. More humeric substances means more fertile soil which means stronger plants and vegetables which in turn means more and better food.
- Humeric substances are ‘recalcitrant forms of carbon’ – they are resistant to further decay so they store carbon in the soil. Adding stable humeric substances to the soil results in carbon sequestration which off-sets the impact of global warming due to CO2.
What could be simpler, compost more!
A text book start for the HOTBIN
The Compost Woman, who knows an awful lot about composting, reviews the HOTBIN! And I’m pleased to announce she has had a text book start as she has already reached 60C!
She started with an very full HOTBIN having plenty of material available for her base layer.
After 24 hours there was already a noticeable difference as the the material started to decompose.
She is a freelance Forest School Leader and Environmental Educator who works with both adults and children on all sorts of things. As well as a volunteer Master Composter and Master Gardener, helping people make compost and grow veg at home or at school.
There is more than ONE alternative to sending food waste to Landfill
Ban food waste from Landfill?
Collect and reprocess it via anaerobic digestion (AD) instead? Well yes and no!!
Respect the 3Rs: we should reduce food waste. Accepting there is always going to be some waste to treat…
There have been renewed calls to ban food waste from landfill in the Guardian today . The report’s co-author Quentin Maxwell-Jackson is reported by the Guardian to state: “Anaerobic digestion technology has so many clear advantages over other waste treatment and energy generation options that it is very surprising it has not taken off in a big way yet in the UK.”
Calls to ban food waste have been made before. The Government’s stated policy is collection and reprocessing food waste via AD.
It is still probably still too early for the policy makers to ban food waste from landfill as the UK does not have the capacity ‘coming on stream’ to reprocess it via alternative means.
Every new AD plant takes time to get planning permission, to build and commission. At out last reckoning, about 3 major were due to come on stream next year and we estimated the UK needed 300 to divert food waste from landfill – it is going to be a huge cost and long path.
AD makes a lot of sense – we need a collection/reprocessing technology that caters for the majority and we know only about 15-20% of the UK population does (or will) home compost and traditional home composting has never been appropriate for all food waste.
We should not let the historic issues of home composting all food waste (including cooked food, meat, fish, bread, cakes, rice, pasta etc) that create a stinky odour that deters people and attracts rats, flies from continually reviewing technology for home composting. The HOTBIN team has real factual evidence that the HOTBIN has changed home composting of food waste for the better. Users have changed behaviour and are diverting all food waste from landfill. We estimate 5m current home composting households could divert all food waste and make a contribution – immediately.
100,000 HOTBIN users would equate to 1 new big AD plant. Delivering a million units a year (we wish!) is a logistics co-ordination issue – the capacity can be made available very quickly. We understand home composting is not for everyone – but we need to make a dent in landfill now and it can be done now.
There are other reasons why AD is not the ‘be all and end’ of reprocessing food waste. Reprocessing is a complex combination of user behaviour, logistics and technical facts. Yes AD has advantages, but so does home composting. Home composting removes the need for collection and transport, the compost can be used in the garden (reducing fertiliser and peat consumption) and adding organic matter and humus back to into soil is essential to soil fertility.
Help us win government support – HOTBIN composting diverts domestic food waste.
[At present we are pushing water up a hill and knocking on closed doors.]
How to compost ALL food waste
Below we explain how to Compost ALL domestic food waste
(i.e. at home, in a garden, or via backyard composting).
Why do we need this blog?
Surely food waste is just like other waste for composting – we just add it to the compost heap and it breaks down?
What’s the big problem? Well to a degree this is true, food waste is carbon/organic and will compost. The problem is NOT that food waste does not compost, it’s just that more often than not, it creates a putrid stinky mush that attracts rats and flies.
What are the specific issues with food waste composting
Here at HOTBIN Composting we talk to a lot of people who compost – from Master Composters, Council Recycling Officers, expert gardeners to complete novices and we have also read hundreds of composting forums and blogs: the advice is near universal: ‘do not add meat, fish, cooked food waste, mouldy bread, left over bones, cakes, bits pizza, chip boxes, dairy products, gone off fruit, out of date fridge contents to your compost heap. If you do, they will rot, produce putrid odour which in turn will attract vermin and flies. Only add kitchen peelings and tea bags,coffee grinds’.
Kitchen peelings,tea bags, coffee grinds only account for 40% of domestic food waste.
The other 60% falls into the “do not” add to a compost heap.
[We know this because very detailed waste analysis of what goes in our disposal bins and onto municipal refuse collection and landfill was undertaken by the Love Food Hate Waste campaign in 2011 (recycle Now, WRAP) . Teams of people sifted and weighed the contents of 1000’s of household waste bins over many months (nice job!). So we know on average, a UK household produces 250Kg/year of food waste. Every item wasted was listed and weighed (what they call a composition analysis), so it is easy to look at the list and reclassify per the compost “in/out” list.]
So even those with a compost bin, will most likely still be sending food waste to landfill.
They might still have stinky food waste sitting in a kitchen or wheelie bin for two weeks. (We accept there is a growing number of councils rolling out kerbside collection to be used in AD/EfW recovery plants – but this is a small part of the total).
Millions of home composters want to add ALL food waste to their compost bins.
This is what why the HOTBIN was invented: ‘to create a compost bin and method that enables millions of existing home composters to compost ALL food waste without the inherent problems of odour, vermin and flies’
Why does food waste rot and go putrid
As food waste starts to breakdown it forms a thick slimy mush. This soft mush prevents airflow and so the waste quickly turns anaerobic. As soon as anaerobic bacteria take over, the waste releases putrid gut wrenching odours. From here it is all downhill – the smell attracts vermin and flies and everything becomes unpleasant. As food is composted, the structure/fibre of the food weakens and water is released. There are three places the water can go – it can drain to the ground, it can be driven off as steam (water vapour) or it can remain in the waste. Under most composting conditions the water stays in the waste until it becomes saturated and then it will start to drain into the ground. Composting soft food waste naturally produces a mushy slime.
The alternative is to use heat produced by the bacteria to drive of water as steam vapour. This happens when we hot compost.
The golden rules for successfully composting ALL food waste are:
- Remove excess water
- Keep the waste aerated
What is composting?
The biggest part of the composting process relies on bacteria and if you refer to our post So What is Composting? you will note their requirements are not dissimilar to what humans need to survive and grow!
So how do we get rid of excess water and keep the waste aerated?
We take a lead from industrial composting and apply the science and engineering they use to a domestic compost bin.
(If you want to look up the science and engineering, have a read through Haug – Practical Handbook of Compost Engineering) on Amazon book review.
Let’s cut to the chase
- To remove excess water
You need lots of heat i.e. you need to be ‘HOT composting’
- To aerate you need to keep adding lots of oxygen/air
Unless you have the means to force airflow (e.g. a pump / blower), or you can constantly turn/tumble (yes we mean constantly), then you are reliant on “buoyant airflow’ or the chimney principle of hot air rising creating a pressure drop that pulls cold air through from below. You only get buoyant airflow if there is a temperature gradient – i.e. you need heat.
- To maintain buoyant airflow (even with heat)
You need to a heap structure that maintains buoyant airflow. To get a structure that stops food waste collapsing into a mush you need to add what we refer to as a bulking agent (typically this is wood chip).
In summary to compost food waste, you need to get the waste hot, aerate it (via buoyancy airflow) and ensure it stays aerated by adding a bulking agent. It sounds technical and it would be easy to achieve where it not for nature’s laws on heat production and heat loss!
Nature has a law on how much heat is produced
Bacteria release heat as a by-product when they ‘eat’ the waste– just like humans release heat when we eat and exercise. The amount of heat is capped by the calorific value – the more calories the more energy and potential heat. The rate of heat released varies by food type.
Think of it like this human analogy – eat coke and sweets (sugar!) for breakfast and you’ll be on a sugar high for a few hours, then hungry again. East oats/muesli and it will be digested more slowly but over a longer period – you’ll make it to lunchtime.
Bacteria are the same – they digest and release heat from sugars and carbohydrate food very fast, from cellulose (plant material) slower, and from lignin (wood) even slower. The amount and rate of heat generated is determined by what goes in and how much goes in. For most households – it is a challenge to create a hot compost heap, you need about X10 more food waste than most households create.
Nature has a law on how much heat is lost
Heat transfers from a hot place to a cold place until they both reach equilibrium, i.e. the same temperature. This law is scientifically defined by Newton’s law of cooling. Let’s simplify it for a compost heap – even in summer (25C), a compost heap will not stay hot (40-60C) for long as the heat rapidly moves to the cool air. If you want to keep your waste hot, you need to reduce the rate of heat loss ie you need to insulate it. There are two ways of doing this – by having a large heap so the outer metre of waste acts as insulation or use a specialist insulation material.
Oh, one last thing – odour, vermin and flies
Lets assume we are now hot composting away. All composting creates odour and food odour attracts rats and flies. Unless you want a heap infested with rats and flies then you are going to need to control odour so it does not attract vermin and control access the compost heap just in case. In other words, compost in a container that won’t attract rats or let flies in.
Successful food waste composting needs heat (for water removal), oxygen (to ensure aerobic bacteria active), which in turn needs a heat gradient, which needs bulking agent to allow airflow. We need to balance the heat produced with the rate of heat loss (insulation, protection from wind) to keep the bacteria warm and composting fast and then protect the whole operation from infestation with rats and flies.
Achieving the above without a specialist bin is very hard.
The HOTBIN was specifically designed to achieve HOT composting to allow ALL Food Waste to be composted. To find out more please visit our extensive FAQ
The HOTBIN composting the whole takeaway!
Composting ‘Vegware’ ™ & Biodegradable bags and containers in the HOTBIN
The HOTBIN was developed to compost all food, garden and grass in the home and garden. We were contacted by Lucy Frankel at the foodwastenetwork.org.uk who is building a food waste network www.foodwastenetwork.org.uk to help commercial business do more to divert food waste from landfill.
We got to talking about using the HOTBIN for small cafes, restaurants and hotels (noting a limitation under ABPR that each commercial site would need to have its own garden/land to use any compost made). Lucy wanted to know if the HOTBIN could handle things like compostable takeaway packaging and asked if we would try some specific tests for her. Lucy works for Vegware Ltd who offer compostable products like cups, tableware, fast food containers and the like.
We were keen to give it a go, confident the HotBin would eat them fast and furious!
What are the composting objectives?
- If the HOTBIN composts them, users can use these containers at home
- If HOTBIN eats them, then possible use of Vegware + HOTBIN at summer events that are semi permanent (ie weeks rather than days) over summer.
We are not suggesting homes will use all these items but on the other hand isn’t it good to know if your Vegware fish & chips, pizza or deli container can be composted at home.
Setup and methodology
- A range of items were received. These were chopped up with scissors.
- The HOTBIN was running at 50C, and the items were just tossed in.
- Each weekend more food waste was added above the Vegware and stirred in
Progress at end of week 2
- Well as expected the more ‘cardboard’ like containers had gone!
- The ‘clear plastic’ (PLA) pots has started to compost (turn white, curled edges)
- Spoons and forks (CPLA) – a lot tougher and will take longer
- There has been no noticeable affect good or bad on the temperature of the HotBin
Progress at end of week 6
- Only one fragment of ‘clear plastic’ (PLA) remains
- Spoons and forks (CPLA) – all but two fragments gone
Looking at the small fragments left – they are soft and have been well attacked. It is most likely that these fell to side and dropped to lower colder zone during stirring.
The HOTBIN eats PLA containers – no problems. The thicker spoons and forks (CPLA) are also eaten – it just takes a little longer and you might need to pass a few bits back through.
Notes on what the materials are made from:
PLA is made from corn starch by Natureworks LLC, and is an ideal replacement for oil-based plastic in a multitude of applications. These include films, thermorformed products such as cups and deli pots, and also injection-moulded products.
CPLA is a proprietary combination of PLA, chalk and other biodegradable additives. CPLA is suitable for high-heat applications such as making cutlery and hot cup lids, as it can take temperatures of up to 85°C without any deformation.
Compost Awareness Week – 6 – 12 May 2012
New research exposes that almost half of the food waste in our rubbish bins could have been composted!
“Compost Awareness Week aims to encourage more people to realise the benefits of home composting and the great results that can be achieved by using peat-free composts containing recycled material”
With a HOTBIN you can easily do your bit to reduce the amount of waste sent to landfill by transforming it into nutritious compost that won’t cost the earth. Recycling your waste is good news for the environment because it helps to cut down the amount of organic waste that is sent to landfill and its good news for your garden too.
The HOTBIN has been specifically designed to reverse overnight how much waste a household sends to landfill. Its clever design ensures all food waste including meat and fish, not just fruit and vegetable peelings can be composted efficiently with less odour and fewer flies in your own backyard.
Designed to help maximize what nature does naturally by bringing together the right conditions to make hot composting easy.The HOTBIN works as you can actively achieve temperatures between 40 -60C. These higher temperatures along with the effective aeration allows the HOTBIN to effortlessly reduce and recycle a wide variety of food and garden waste into great compost all year round. In fact at those temperatures you can expect to harvest a batch of beautiful ‘black gold’ every three months.
The HOTBIN has been independently tested by Garden Organic for ease of use, effectiveness and quality of compost produced, confirming that high temperatures can be maintained to provide sanitation of waste, including cooked food.
This is why the HOTBIN is a home composting system that recycles a whole lot more than potato peelings! Just think you will be returning all those lovely nutrients back into the soil. You can even save water too as using compost can increase the ability of your garden to hold water.
The HOTBIN is made from a robust engineering material called expanded polypropylene bead that is also used on car bumpers. It has been chosen for its hardy and insulating properties. The HOTBIN is made in the UK, 100% recyclable and invented in Morpeth.
In our recent customer survey more than 90% of users agreed that it was important to have the ability to compost cooked food waste; 61.5% of users are adding all food waste to their HOTBIN and 64.9% are now diverting a lot or nearly everything from Landfill.
And here are just a few of their comments!
‘My HOTBIN is a talking point at dinner parties as composting is now much more interesting.’
‘My HOTBIN takes the grubbiness out of the composting process’
‘My HOTBIN has made me more conscious about our waste and recycling’
‘MY HOTBIN converts waste into good stuff for the garden’
‘MY HOTBIN produces something for nothing to put back on my garden’
Why compost food waste?
Recycle more food waste
An estimated 6.7 million tonnes of food waste is collected by UK Local Authorities and sent to landfill.
This is approximately 150-250 Kg per household per year (ref. WRAP, 2010). Around 7m UK homes already home compost, but they compost as little as 35% of their total food waste. Typically adding vegetable peelings and tea bags, but not plate scrapping, meat, fish, cooked food, rice, pasta, leftover bread, cakes, etc. The main reason food waste is not composted at home is smell, vermin, yuck and mess (ref Defra funded, Brook-Lyndhurst 2008).
Home composting of all food waste has environmental benefits as it reduces fuel used to collect and transport waste to landfill, prevents methane release in landfill, [methane is a potent greenhouse gas] and reduces the number of new industrial composting / anaerobic digestion plants required in the UK.