openspaceman

Forgetting RHI is probably good The amount of wood needed depends on its efficiency, no matter what device you use. It does look a bit expensive and would need lots of manual refuelling. The efficiency here would depend on the flue temperature as that is the only wasted heat. One thing it has got going for it is that it avoids the need to heat water so only one heat exchange surface but what temperature would you run it at? It looks like it's for a workshop at room temperature rather than 60C. If you refer back to Duffryn's first post today in this thread you will see his first option is a straight through system. If we were using natural gas to dry say paper slurry then there would be no need of heat exchange surfaces. Consider there is a loss at each heat exchange. So one could run a flame direct onto the wettest wood with enough bypass air to prevent scorching. The wood would have to be moving into the container consistently and probably require more than 12m to make sure you got maximum heat into the wood. If you had a clean enough wood chip stoker burner it would be an interesting project. Back in the 80s it was possible to buy a cheap 150kW(t) Veto stoker-burner which would be ideal as long as you had some dry arb wood chip and maybe some dunlop coal to get rid of. Having said that there's nothing difficult about building a chip stoker: A feed auger, rotary valve, stoking auger, fire brick and fans plus a couple of inverters and Programmable Integrated Circuits. In practice it would pay to jig the basic concept about a bit to make it workable as the solely concurrent flow doesn't make best use of the heat. It could make a nice retirement project.

BigJ is the expert on this I think. A dehumidifier is a heat pump it compresses a refrigerant back to a liquid, which releases heat and is blown into the container then it allows the liquid to evaporate, this requires heat so a cold spot develops which is below the dewpoint of air in the container so water condenses and runs into a container, all the electricity is turned into heat and there is no net change in the container as water has left the wood and then drained out still as water but again it's a low temperature method, great for drying wet clothes. In practice it's likely to be cheaper to add a bit of cheap heat and still recover the moisture as liquid via a heat exchanger, there is a thread where this was discussed.

Road pins and two luggage screens from a Ford Focus estate

I reckon on nearer 4kWh/kg with hardwood at 20% WWB and that allows for dumping the flue heat at about 150C, Cornishwoodburner manages to extract more heat as he runs a low flue temperature, softwood can be a bit more because it has a higher lignin content.

Not done it but wouldn't advise it other than low temperature lumber drying. The thing is that heat pumps have a Coefficient of Performance which varies inversely with the difference in temperature you are pumping through. So assuming your heat source can stand the heat removal ( and the one I remember couldn't as the pipes under the lawn froze the soil and could be seen as a network of ridges ) then it's good for underfloor heating as you only have to pump up to about 25C and the COP will be better than 3, that is 1kW(electrical) in will deliver 3+kW(thermal) out. However as has been discussed log drying benefits from higher temperatures than 25C and the COP would drop if you could find a pump capable of running at 60C out.

Thanks, I'll have to buy the ingredients as I don't grow my own but shall try this.

pologies to mikerecike all those years ago but here is the picture of the socket I used

Not to mention stag beetle larvae if you are in the south.

It was done with a back acter. This was the same chap that took in a load of leaf sweepings as mulch from the local parks department, he hadn't reckoned on the loading with simazine.

Recipe?

Sounds like yours runs at a fairly high temperature in the kiln to get it down to 20% in 3 days and a bit. In the hardwood lumber industry the kiln just finished off the drying after the boards had been in stick for a season, not sure about imported softwood, but the same can apply with logs. They don't necessarily have to be dried from 45-50% down to 20% in the kiln. BTW is that 20% measured straight after the kiln is opened or after the log has "normalised"? I found my test pine log which was oven dried still hadn't gained much moisture and was about 10% from sitting in the shed, I had expected it to get up to about 17% by now. I shall have to devise a rewetting experiment to see if the higher temperature treatment resists re adsorption of moisture from the air.

30 years ago the curator at RHS Wisley wouldn't allow grinding, roots had to be removed and taken to a stump dump for burning.

I'd say it was exempt as a mobile piece of equipment but the use may constitute a change of use of the field which they could enforce. You could try it for 28 days and see if anyone objects.

Horses seem to like tanalith treatment

My post was my inference (and she didn't mention saprophytic) as she was initially talking about the necessity for fungi to decompose dead wood on the forest floor, I'm open to further enlightenment. I took the view that pathogenic fungi would have evolved to get in through defences and attack the tree rather than sit and wait for the tree to discard a branch?? The trigger for their activity being the lessening of water content.

I'll have to search for that, I thought I'd have much more time on my hands for such things but my DIY plumbing has escalated from changing a tap to having to replace the whole basin due to my hamfistedness. What I should like to clarify is that Lynne Boddy was referring to saprophytic fungi sitting dormant in healthy tissue and waiting for the parent trees efforts to discard a branch after abscission causes the loss of water, rather than a response to drought as I implied.

It was a bit more than thought provoking for me, I haven't kept touch with this arb science but was gobsmacked with the idea that progenitors of fungal bodies were already in the healthy tissue waiting to grow once the branch came under drought stress.

I cannot remember what ours was but I never had that trouble. I would have thought that as long as water is circulating through the mixer there would be enough heat. Anyway what about warming it up with a hair dryer?

Check the engine has some antifreeze and that the water hose is getting warm. The thing is that unlike blow torches, which draw gas from the top of a bottle, vehicles use a liquid take off, this liquid then has to be turned into vapour before it enters the mixer and meets air and is sucked into the engine. In turning from liquid to gas energy is needed (the enthalpy or latent heat of vaporisation) and this heat comes from the surroundings, in the case of a water cooled engine the engine coolant supplies the heat. If the coolant is not circulating this can cause the vaporiser to get too cold, any water in the air then condense on the vaporiser and then freezes. You will see the same with a normal propane bottle in cold weather as the frost line shows the level of propane remaining in the bottle. Normally there is enough thermal mass in the vaporiser that supplies heat until warmer water starts to circulate.

Tom and Brushcutter are right, the last thing you want is back pressure in the return pipe as this can pop out the seals at the end of the spools. In your case it fails safe as it is the supply that is popping out but it is always best to return direct to tank rather than through the return of a spool as there will be less back pressure and hence less heating of the oil.

That takes me back to those early APF shows where Jones would have a skyline running and Highland bears forwarding the produce back to the end. I briefly worked on a Igland skyline near Port Talbot in the late 70s and found it one of the most strenuous and frustrating jobs. The boss's wife ran the tower . Here is a picture of my mate putting up an intermediate support, note the Goliath boots and full safety gear:001_smile: However I did buy the double pulley and snatch block to extract when felling a carr, I never did become competent with the control and had lots more frustration unwinding the block when it got tangled. I cannot remember being able to use it downhill which would probably suited better. Working on SSSIs and ancient woodland I thought it would be the way to go because of the lower ground damage but by 1984 I had given up and gone the shortwood route with a tractor mounted grapple.

My point was I don't trust the phytosanitary controls. having experience of their falsification. My brother in law used to import "specimen" trees from a nursery in Holland, they were all grown in Italy because they could reach a saleable size in 4 years which took him 10 years to grow in Surrey.

I know nothing about plant passports but the restriction on issuing a certificate with ZP for Plane Wilt seems to have expired in April 2016 unless it has been renewed on a later document. I do remember a ship load of beech with bark still on bound for Turkey being issued with a phytosanitary certificate stating it had been treated with ethylene bromide ( the use of which was probably banned in UK at the time) .

I don't know about these but I do know that you need a 2m3 or bigger bucket, 54 trips with a standard JCB bucket just takes too long and uses too much machine time.

Yes in most cases it is and in these cases it doesn't compete with the common alternatives, like coal for instance. So in a competitive market and as labour is the major part of the cost of production one needs to create brand loyalty. This is a form of monopoly to enable you to sell an apparently similar good at a higher price. I see things sold as "EDGE" at the moment, I haven't looked up what it means but if it appeals it becomes part of the Unique Selling Point that gives a competitive edge to your product in exactly the same way "kiln dried" is being used. Now I'm easy either way with "kiln Dried" or "hand crafted" logs and when I sold logs( over 35 years ago) they were only partially air dried because I did not have storage facilities, so my customers expected to store logs in a dry place before using them. That model would appear not to work now. When a client had a business model that pointed to needing a quick turn around from raw material to sale because because they could not sustain the cashflow of stockpiling kindling, which only had a demand from October to January, then kiln drying was a good option and energy considerations did not come into it any more than flying blueberries from Peru for Waitrose (very tasty with ice cream) to sell. That's economics. If you feel that on principle it's wrong to do something that's fine by me but, like me, you will have to forego the riches a competitor that ruthlessly exploits the market can make.