Wednesday, 13 January 2010

Hilarity Benn talks rot.

A lot of years ago, I was involved in helping set up a project to dispose of abbatoir waste by fermenting it, rather than burning it. The trouble is, meat doesn't actually ferment in the same way as sugars and it produces a lot of really horrible products - including vapourous chemicals called cadaverine and putrescine, among others, the names of which should give you a clue what they smell like. Oh, and ammonia. Loads of ammonia. And absolutely astounding quantities of CO2.

Have you ever come across a days-dead bird, mouse or hedgehog when gardening? Imagine that scent on an industrial scale and ask yourself where you could put such a facility. It could stink out a medium sized town.

We came up with the idea that we could mix it with carbohydrate-rich waste, such as straw, to reduce the stench. When microbes have no carbohydrate but lots of protein, they break the protein for energy but they can't use all parts of the protein for energy. Lots of nitrogen gets dumped as ammonia and lots of spare bits of amino acids and cannibalised protein fragments get dumped as vile-smelling compoiunds. So, we thought, give them carbohydrate and they'll use the protein as protein, thereby reducing the production of the stinky stuff.

The other thing a large scale fermentation like that produces is heat. Lots of heat. Enough to be useful in energy generation or simply as a piped hot water supply. The little compost heat in the garden gets warm due to fermentation but scale it up and soon you're talking serious heat.

Unfortunately, too much heat will kill the microbes and the whole thing will stop. Running cold water through pipes (and taking warmer water out of the other end) would help with that but even so, the design was a nightmare. You can't easily mix something that's criss-crossed with pipes. We'd need a few pilot plants to try it out. Big expense, and pilot plants don't always scale up easily.

That expense was one reason the idea folded. Another was supply of materials. We'd need the right proportions of carbohydrate to protein to keep it running without having to supply nosepegs to the local population. Abbatoir scraps and supermarket discarded meat would not be likely to arrive in a constant, predictable flow and neither would straw or other carbohydrate waste. The quality of the protein in the meat and the carbohydrate content of the straw would vary too. That's just nature.

Then there was the disease aspect. Plants get diseases, but nobody's ever come down with a case of rust or wilt or stem-rot. Animals get diseases that we can get too. The meat for disposal would not be subject to hygiene regulations (that would be silly - if it passed hygiene regs it would be safe to eat!) so could be crawling with all sorts of nasties. Those might be killed in the fermentation, they might not, they might even grow nicely in there. So the composted end product could be a seriously hazardous material and we'd have to burn it. Hence, fermenting it would be a total waste of time.

Metals such as copper, mercury and zinc accumulate in animal tissues. Composting won't get rid of these. They are elements. The composting process risked concentrating these metals so if the compost were repeatedly spread on land, the land would become poisoned and grow nothing. Getting the metals out was far too expensive to be viable.

The project was binned as it was not feasible. Vegetable matter is easy to compost, it breaks down into useful material, is safe and if done right, it's not stinky. Meat composting won't work. There are just too many problems, both with doing it and with dealing with the end product. That discussion happened about twenty years ago.

And yet Hilarity Benn plans to make everyone put all food scraps into bins and then force the councils to do something useful with them, such as composting them. As I understand it, Hilarity is a vegetable so wouldn't be throwing out any meat waste, and as he's an MP and therefore not very bright, he won't have realised that other people will throw out meat waste and in some cases, quite a lot of it. He will, no doubt, insist that supermarkets and butchers dispose of food waste in the same way which means there will be occasional huge surges of protein going into those council composters - and a day or so later, a stench that will have everyone for miles demanding gas masks.

Many people, as a result of previous green drives and low-frequency bin collections, will have taken on their own composting bins for garden compost. They'll put all their potato peelings and apple cores in their own compost bins, so the proportion of meat going into the slop buckets will be very high. Which will make matters worse at the council facility.

If they start building a composter near you, sell your house fast and move before they finish it.

On another note:

He [Hilarity] told MPs: “Should food waste continue to go to landfill? I don't think it's sensible that it should.”

Glass, plastic, paper and card don't go into landfill. Batteries are collected separately. Electronics and white goods are separated. Now, no food scraps. What actually goes into landfill these days?

Oh, and in case you think this might not be such a good idea and decide not to go along with it...

The Department of the Environment, Food and Rural Affairs is drawing up new rules on separating food waste, and is known to be considering allowing councils to impose fines of up to £500 on households who do not comply.

Slop buckets in your kitchens, or you get fined. As others have already spotted, Lord 'Basher' Tebbit has described Labour's idea of the 'carrot and stick' approach perfectly. I think it might be time to add a new blog to the list.

If these council waste fermentors come to reality, they will represent the most telling legacy of the Labour party yet, by filling the country with the true stench of decay.

I hope Hilarity leads the way by having the first one next to his house.


Mark Wadsworth said...

Trying to rot the stuff down does seem a bit mad.

To be fair, the 'green' bins have little stickers on them saying don't put meat in'. But what is the best way of disposing of it? Just leave it in a field and hope the vultures eat it? Burn it? Feed it to other animals? Landfill - in which case, won't it still stink?

* I favour burning of course, if you get the oven built properly, it will burn itself, so you get a bit of heat of it for electricity or whatever.

Paul Bailey said...

Since when has any politician let sound scientific principles get in the way of their madcap schemes??

paulo said...

Of course 50-60 years ago all food waste was fed to pigs and as a result the pigs tasted of pork. Obviously nothing so sensible could be re-introduced...

God help us!


Leg-iron said...

Mark - there was a study into the 'spontaneous human combustion' myth that showed all you need do is start the fat burning on a corpse and it'll burn like a candle. So it could be used as an energy generating system.

Won't work in crematoria because it takes far too long and leaves the extremities, which won't go down well. For a pile of meat waste and fat though, it could work.

Leg-iron said...

Paulo - Elfin Safety have that covered. You can't just feed animals on anything you like any more.

There's just too much risk of food-borne disease (although there wouldn't be if people cooked it properly).

We aren't allowed risks. Too risky.

Tomrat said...


They do now use microbes in animal processing plants; mainly to deal with sleuce pipes which get clogged up with grease and other undesireables (yummy). The last supplier I attended a presentation for before losing my job at the chemical distributors I worked for was one such company specialising in microbes, GM and enzymatic products for every industry imaginable, including the ones you mentioned.

One thing that angers me is how much energy is wasted because of poor understanding of how we process waste materials; given the correct conditions there is so much we could do with landfill it gets me angry - its like that Pratchett novel I read moons back in which an engineer is comtemplating how to power a horseless carriage seconds before cursing and removing a boiling kettle from a stove...

Agree with you though on the Cadavarine and Putrecine - wrong on many levels, but not as bad as 1-pentanol; we once had a bottle of that in the lab we dared each other to open...under a fume hood.

On the heavy metals side of things though wouldn't it be possible to sequester them into the froth exuded?

Bugger said...

Bio digestion does and could work but it is just too complicated to get the RM in the right %.

Mix it with human crap and then stir some bacteria of the right type does work.

I a available for consultation at a modest fee, say some bamboo shoots, sweet and sour and a nice we red biddy.

TheFatBigot said...

"... nobody's ever come down with a case of ... wilt" - don't tell Pfizer.

TheFatBigot said...

My sister once had a small wormery and would deposit meat in it as well as green waste. As far as I know it worked well.

microdave said...

It's scary to realise just how many apparently "sensible" ideas aren't sensible at all, when you delve a bit deeper...... Like wind power, which is currently providing 0.7% of our electricity supply!

I'm going to print that explanation out, and pay a visit to my local council with it. I don't suppose it will make a blind bit of difference, but at least I will have tried.

(Can I say "blind"? - "visually handicapped" wouldn't sound the same....)

Mark Wadsworth said...

"Mark - there was a study into the 'spontaneous human combustion' myth that showed all you need do is start the fat burning on a corpse [etc.]"

At the risk of being politically incorrect, the crematoria in the Nazi death camps did not require fuel, the corpses burned themselves - it can be done.

gareth said...


When you got to adding straw to the waste it sounds like you are talking about a form of bokashi bran composting.

Giolla said...

I have a "hot" composter Green Johana which allegedly does all kitchen waste but do have to put in at least a third green waste and the odd bundle of twigs. Seems to work though.

Tried a wormery killed them all within a few months.

subrosa said...

The little food waste I have goes in the main bin. (That includes potato peelings because if they go on the compost all I get is more potatoes).

I refuse to turn my kitchen into a recycling plant.

Leg-iron said...

I once dumped a whole potato in the compost because it had gone soft. That's a mistake I won't make again. I was hacking back that thing for weeks.

Recycling is something I do because I like the idea of it, but there has to be a point. There's no purpose sorting out all that stuff if it's going in containers to Argentina or China to be dumped.

All the same, I like the idea of recycling. I don't like the idea of being ordered to do it. That sort of thing will stop me liking it, and then stop me doing it.

N.B.SALAMI said...

Hilary Benn should be put in landfill. And his father

Mummylonglegs said...

I was asked (forced) to trial a slop bucket last year. At the end of the three month trial I was asked why my slop bucket had remained devoid of slops. I replied that I had no slops with which to fill it. Cue audiable intake of breath from clip board Nazi. You must have slops. Nope. But you must. Nope. I cook the correct amount of food per meal. Peelings go in the compost. Veg scraps (cooked or uncooked) go in the compost. Meat scraps go in the the freezer or in the dog. Egg shells are ground up and used as a slug deterrent. Every two months or two the compost is mixed and a healthy dose of well rotted horse shit is added. What about chicken bones. I don't cook a whole chicken, it's a waste. I don't buy any meat on the bone, why would I pay an extra pound or so for something I can neither eat nor use. What about food that has gone out of date - cue laughter from me. I have three growing Squids, it doesn't last long enough to go out of date. I was possibly more confused than the CBN. They want me to recycle but believe I can only do it via the state. I have also had two visits regarding the lack of recycling in my recycling bin. It's pretty much empty because I have already recycled it. Eh?. All paper get's shredded and given to a friend who runs an animal sanctuary. Boxes, milk containers, squash bottles etc go to the school for junk modelling. Ice cream tubs, take away/ping meal containers etc are kept to re-use. Funny though, I'm looking out my window right now and all I can see is a mass of black bags, containing all the stuff neither the state nor myself can recycle. It's been sat there 4 weeks and is growing by the hour.

Mummy x

At least the Government has one part of their grand recycling scheme right. When an MP passes it's use by date, smells a bit off or is down right rotten they send them off to The House of Lords. Reduce, reuse, recycle at it's very best.

Dr Dan Holdsworth said...

The other easy way to get rid of kitchen waste is to get a home macertor unit, of the sort designed to be fitted to a kitchen sink. This turns food waste into slurry, to be washed into the sewage system which is already set up to cope with high-nitrogen wastes. Obviously this solution is a wee bit obvious for most politicians, doesn't involve putting a lot of people to a lot of trouble and actually works quite well so it'll never actually get suggested but just keep in mind that it actually works, works now, and doesn't cause long-term problems.

Sir Henry Morgan said...


Wilt is not the same as droop. Pfizer is secure.

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