We’ve covered wood-based cat litter before but we’ve had a rather unusual email from Simon and I thought it was worth returning to the topic:

I’m e-mailing from an independent animal sanctuary in Northern Ireland.

We have about 100 cats here all using wood chip litter and would probably skip at least 100 litres a week. Do you know a way of turning the used litter (poo-free!) into burning fuel, and would that be more environmentally friendly than oil? I’ve experimented trying to compact it into short pieces of sewage pipe, but the problem is keeping the litter in one block.

To give you an idea, we would spend about £2000 a quarter during the winter on heating kennels and catteries electrically.

I’d be grateful for any suggestions, even if it’s to say “For Christ’s sake, what are you thinking man?” as it feels like we could be using this used litter for producing heat.

I tempted to say “For Christ’s sake, what are you thinking man?” just for the humour but I can see where he’s going with this. I guess it would be particularly galling if you had a biomass boiler or stove for heating: throwing away all those wood chips only to buy different ones back for burning.

This is basically an appeal for help/information/tips anything that might get Simon started on his way or conversely warn him off the plan if it’s unsound.

Anyone know if this is viable? As Simon says, the litter is poo-free but I presume it’s been wee-ed on – would that cause any problems for burning?

Any suggestions on how to make logs stick together or make pellets?

I hear that biomass boilers/stoves are quite expensive to install – anyone had any experience with this? Anything special Simon needs to consider?

We’ve had an email from Ashley Sue, asking:

What is a good sustainable use of 40 lb plastic empty kitty litter containers? I’ve got a bunch of them. not recyclable in our area :(

We get our cat litter in paper sacks so I’m not quite sure whether Ashley Sue means bucket-like tubs like this one or jug-style containers like these. The link on the former already give one potential re-use — for growing veg — and we’ve got a few of the latter type that originally held dry cat food which we use for other cat-related purposes – either mixing up two flavours of dry cat food to dilute one they don’t particularly like, for holding litter when the paper bag splits or if a bulk-bought sack of food/litter needs decanting so the smaller member of our household (ie me) can lift it. I’m sure a well-washed out litter jug could be used for all these things too.

Any other (cat or non-cat) suggestions though?

(Oh, and if you’re interested, we’ve already covered recycling/composting the litter itself. Also, can I just say how delighted I am that it’s spring and the cats are leaving the house for the first time in months – it’s been a long, long poopy winter.)

We’ve had an email from Andy Whittington about a subject that is close to my own heart (and nose):

We have two new feline housemates, and the accompanying cat litter with waste, does anyone have any idea how I can reuse/recycle this after the solid waste has been removed, and is the sawdust product more eco friendly than the porous stone chip version?

Congratulations on the new additions to your household Andy and welcome to the world of sitting on the floor because they’ve snagged the best chairs and refuse to be moved.

As I say on our sister site Compost This, it’s tempting to compost wood-based litter but poop parasites can cause a problem. Our garden is too small for multiple compost heaps but my mum and dad have a heap they just use for litter and accept that it’ll take ages to break down and not use it on their veg plot.

If the poo is, well, perfectly contained, then it’s less of a problem because it can be disposed of separately and the absorbed urine might actually help your compost heap because it’s nitrogen based. Just be careful to keep the heap balanced with other materials if you want it to breakdown in a reasonable time-frame.

I don’t know for sure about the eco-friendliness of the wood-based versus clay ones (does anyone else?) but I suspect (read: hope) that the former is a waste byproduct of the wood industry. It is also less likely to cause clumping issues for the cats. We’ve also tried recycled paper-based litters – they worked alright, just left the room smelling of damp paper – and if poo-free, could be composted like the wood ones.

Any other thoughts? Anyone know if the clay-based ones be used as aggregate in concrete or anything like that?

(Photo by mzacha)