Reducing ash when burning pits.

Hi All,
Here is a bit of general information which is really aimed at Aussie pit burners but may have a bit of interest to anyone Stateside who is burning multi-fuels.
Olive pits like other nut like fuels can be very ashy. Mixing in some wheat helps but the ash pan can still require cleaning out every 12 hours. The pits burn partially and then are blown from the pot as they lighten, this leaves a lot of material in the ash pan. It also risks the holes in the pot being exposed at which point the fresh unburnt pits fall straight through and the stove goes out.
My mate Gav who lives near the pit pile has developed a a plate which goes over the pot to stop the pits from blowing out. He says the pits then burn down much better. He was going to send me a photo but hasn't yet. C'mon Gav; give it up!!
I have been experimenting a little. When burning with wheat we use a set of side wings to to stop the wheat bouncing out. I have bent the wings out straight and put them back in like you can see in the photo. The idea is to funnel the cascading pits back into the pot to be reburnt. Like Gav's experience this does seem to work.
From the photo you can see that I have the wings positioned forward so there is a gap at the rear fire wall. This allows for some pits to escape as I found that the pot was filling too quick if none was getting out. From the photo of the ash pan you can see that after 12 hours the ash is less than 1/2 full and the fire has been running on high overnight. Normally by now it would be chockers and would have to be cleaned out. I am certain it will make 24 hours no problem plus the material in the pan is burnt down better with less half burnt pits.
The pot itself is quite full (which you can just make out in the photo) after 12 hours but the fire is still running hot at 410 Celsius. I have just emptied the pot with a soup spoon, thrown in a bit of cat litter and relit without issue. The risk of using the spoon is that you force ash through the pot into the air chamber and choke the stove, so at 24 hours I will tip out the pot and scoop out any ash in the air chamber with the spoon. All of this can be done while the fire is hot provided you have the 2 tools shown, no need to wait for things to cool down. The offset pliers are especially good as they allow you to pull out the pot without having your hand over the heat, much better than normal pliers.
I have found that the fire is burning hotter so I have reduced the feed settings to maintain a good running fire temp. The fire has been running on high mostly but my low setting seems to working okay as well. I have also reduced the set temp down to 22 Celcius. You can see the settings I am running in the photos, these settings would not work at all without the wings in. I have also taken out the spreader bar as it did not seem to be helping either. After the 12 hours the glass wiped completely clean so I think the fire is burning very clean. My exhaust setting reflect the fact we have a hard drawing vertical flue so horizontal flues may need to be 5 volts but these are a good starting point. The number 1 setting is 140v, I have No.5 at 185 as we are using Breeders Choice cat litter which is harder to get going, if you have Woolies Select brand then I would back down to 170-175v. You can see from my start fuel settings I am really heaping it in as I am concerned that with the lower running rates the pot may still blow out so I am trying to build up a bit of pit base. This may be unnecessary so I would leave the start settings wherever you have them for a start and see what happens. I would not let the stove start on low however. I did do the restart on low without issue but the stove was still at 280 Celcius when it relit.
This may have some benefit with the hazelnut and macadamia nut burning but it sounds like the maccas work fine by themselves without any messing around.
Another plus you can see is that there is a slightly bigger flame on high which looks nicer.

 

WE have a similar issue on the Big Whitfields with the shells falling through the grate.

I cut a piece of stainless steel that just covers the grate and drilled rows of 1/8" holes that align with the grate slots.

This keeps the shells from falling through and the burn is far better.

The amount of ash is still much higher than wood pellets, but no worries.

Thanks for sharing