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openspaceman

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Everything posted by openspaceman

  1. It was the whole CPSC bit and IMO any other certificate won't be an investment. If you're not on a building site or FC land you may get away with just proof of training.
  2. No it was more of a dictatorship
  3. A couple of lads I worked with went to MI Training at Godstone, even the dopey long haired yoof got through
  4. Define usable? It probably won't be saleable to the barbecue market, softwood is too light, doesn't last as well and too friable to travel but it's ok to cook on. I made some sticks of pine char that would light with a match and burn out on there own to just white ash, wrap a few in cerablanket, stick them in an old tobacco tin and they work as a hand warmer.
  5. The Viper was technically a kiln rather than a retort. The output looked more "coked" than the shinyblack the market required. IMO kilns offer some advantages over retorts. I think the big Simcoa kiln for making jarra charcoal for silicon smelting was interesting but even that was shutdown.
  6. What I didn't calculate was the duration of the electric winch and 2 95 Amp-hour batteries to 50% depth of discharge, it's about 1 hour of full on pulling. I guess a chainsaw will run about 30 minutes on a full tank on load?? but a days worth of fuel only weighs 8kg
  7. I would go for something in hand portable bits and use a wheelbarrow. Lets consider what power we are using as dragging something along is force time distance =work and work per unit time is power. Tirfor input power 200 Watts at best but what is the conversion efficiency, I've a feeling it's not good, say 70% gets into the load. Small 4000lb winch say about 1000Watt and probably over 90% efficient. Portable Winch 1600 Watt and similarly 90% efficient Lewis winch with 60cc husky 3100 Watt similar efficiency So the Lewis should do the job fastest but it costs £750 plus Vat and you need a 60cc saw. I have never used or seen a Lewis or portable winch.
  8. Maybe for some rufty tufty he men but having spent some minutes hauling a t16 through a carr to pull a fallen alder that was blocking a drainage ditch last week I'd opt for some fueled assistance. The portawinch looks OK, is as light as the tirfor and wire but only pulls a tonne and costs £1500+VAT. if you have the work I'd consider this with a snatch block or two. My colleague recently tried the alternative: he bought a 4 tonne 12V winch and mounted it on a plate, equipped with 2 95Amphour batteries it pulled 2 large trees out of the Thames but both batteries were flat by midday (and I doubt it did them any good being deep discharged). The advantage is the winch can go on a vehicle after but it needs 2 men to carry it into site and 2 trips with the batteries. It only cost £300 but would need a portable battery charger (about £400 or one could build one from an old mower and transit 65A alternator cheaper), Pulled a true 4 tonnes but very slowly. I'd be tempted to go down the hydraulic route with a 4 stroke power pack. by candlelight
  9. The bracken control group negotiated licences to use Asulox but I doubt anyone will do this for Timbrel. As I understand it any existing stocks of Timbrel may be used before November.
  10. I cannot see this being a reason, one of the attributes of a retort over a kiln is that all of the solid carbon in the charge is retained and the char contains more volatiles as temperatures are much lower, so yield of over 40% of the dry weight are possible. It's great for easy lighting and UK barbecues but people who are used to a well cooked char, from countries where jiko type charcoal stoves are traditional disliked it as too smoky. IIRC we used to get £1.70 /bag delivered on the bioregional scheme but I cannot remember the weight of the bag.
  11. I'd not go as far as you as extolling the benefits is all cases but I did successfully make a high ash biochar by running a chip stoker on low primary are and speeding up the grate. The biochar was well cooked and high pH as a result so would have worked better on acid soils growing veg rather than horticultural stuff like rhododendron.
  12. Probably but I was thinking as the land owner rather than a contractor. Yes the contract for the work would be with the landowner client and there would be none other than a duty of care with the neighbour.
  13. Sorry, well spotted, I meant three years, is there a way of getting this edited by a moderator?
  14. If we agree that the branches were trespassing but the nuisance was not actionable (e.g. no damage was being caused) and the aggrieved party has the right to mitigate the nuisance by cutting them off and they remain the property of the tree owner then I would say the tree owner could be approached for the disposal cost if they do not accept them back. However they are now waste and must be dispose properly. This perennial problem will only be settled if some warring neighbours take it as far as the high court and get a precedent set. In the meanwhile talk to neighbour first, tell them what work will be done, ask if they want any of the arisings and if not dispose of them as normal.
  15. Boozy evening? I was specifically replying to a post that referred to taking and returning a supply on a tractor via the service spool.
  16. Yes that's why I posted the warning, though I have only seen it blow the seals on one occasion with a hired in JD. The thing is the JD has a zero pressure return in the back axle but the fitter didn't understand the concept so took feed and return to the service spool. Yes, in the old days it was not a problem as many tractors only had the trailer tipper so you returned through a back axle level plug. We used a Dowty coupling with the guts removed (in case one forgot and coupled the supply first, messy as oil got dumped) with the advent of double acting spools and quickfits it seemed much easier to simply put quickfits on and go direct to the service spool outlets but damaging. So whilst it's okay to take a high pressure supply from one side of the service the return should be direct to the reservoir and preferably without quickfits. In practice I have stuck with the quickfits for the return but always couple it first.
  17. I think the one day course is for staff in low hazard environments. Best to do the 3 day FAAW course and update with 1 day refresher every 3 days IMO. Currently mine have lapsed and I just have the appointed person competency, which means where I work there should always be a first aider but if it's him that gets ill I should be competent to cope
  18. Apart from this problem of mistaking the feed and return pipes I consider it to be wrong to return the oil via the other port of a double acting spool being used as the feed because it causes an unnecessary flow retriction. This increases the losses, increases oil temperature and the back pressure can cause leaks around the spool O rings. Instead return to a zero back pressure point, preferably below the oil level.
  19. I imagine this is the temperature you measure inside the charge chamber rather than the combustion space? It's the temperature that you need to heat the wood to for it to self sustain pyrolysis, between 330 and 440 C pyrolysis is reckoned to be mildly exothermic, above 440 and you have to supply energy as a proportion of the tars form tiny pieces of graphene like ring structures. The temperature in the firebox will be anywhere between 800C-1600C in places and the steel shell will have a temperature bof an average between the two temperatures on either side. The difference between these two temperatures is what I referred to as the delta T. Heat flows from hot to cold temperature reservoirs. The amount of heat flux from hotter reservoir to the cooler one is a direct ratio to the difference in temperatures between the two reservoirs (the delta T), so to make more heat transfer into the load of wood you want to pyrolyse you either have to take longer, increase heat exchange rate or increase delta T. The reason you need to put heat into the raw material is: 1 To raise its temperature to 100C 2 too boil of water and then other volatile organic compounds 3 to raise it to around 330C Of these 2 requires the most heat, so it pays to use dry wood. I think you mean the charge chamber is initially heated from a fire underneath, once pyrolysis is initiated offgas from the charge also contributes to the heating. Yes as I said above the average temperature the charge chamber suffers is the average of the firebox and the charge chamber temperatures. The big limitation of this sort of retort is the small heat exchange surface the walls of the retort provides plus the reliance on natural convection and conduction to move heat around inside the charge chamber.
  20. A lady I know virtually, Priya Karve, was making char from sugar cane leaves in India, using the design of another virtual acquaintance, Yury Yudkevitch, and opted for a number of stainless retorts and they lasted no better than mild steel. The trouble with most retorts is getting a decent heat transfer and to do this the firebox temperature is raised to get a high delta T across the wall, which limits its life. The aim should be to get better heat transfer into the retort and keeping temperature less than 700C.
  21. It's a considerably worse conductor than mild steel but the real reason it's not used in retorts is that it depends on a thin layer of chromium oxide forming, this is refractory in normal use as long as it is in an oxidising atmosphere, otherwise the layer gets attacked by acids and it loses its resistance. The inside of a retort is oxygen free, or the charcoal would burn, and the offgas given off during pyrolysis is pyroligneous acid...
  22. Transit 280 with a window in side door and 2 rows of extra seats will do all those except the 40mpg (I got 34 on a long run) and price is dependant on how old.
  23. Yes, PICS are generally in the soot so a standard smoke test will give an indication. I have a feeling that PICs will be related to CO:CO2, my home-made burner ran at 30ppm CO and seemed to be clean but I never had other analysis tools so never did find out how good it was. If there is any visible smoke you have PICs in abundance. Dioxins are a different matter though and depend on how much halogenated hydrocarbon is in the feedstock. PVC is the obvious one and neoprene, if you burn it hot enough and quench the flue gas quickly they can be minimised but then you notice a cloud of vapour above the flue, this is the chlorine recombining with hydrogen and then sucking water vapour out of the air to rain as hydrochloric acid. This has interesting effects on stainless steel flues. As I said not only the sensors; I've seen a greenish deposit below a EGR pipe which was the first indication that acid had etched out the iron and micro perforated it, from the outside it looked fine. The cure should have been to only burn clean chip but insulating the pipe to prevent condensation solved it. I never did decide if it was an iron chloride or sulphate on the floor. The plastic wire you mention will almost certainly be PVC covered. You need to look at exemptions U10 or U11 https://www.gov.uk/waste-exemption-u11-spreading-waste-to-benefit-non-agricultural-land
  24. It didn't used to be acceptable for pallets but was taken for cable drums (Pirelli) and dunnage.
  25. There is certainly a higher mineral content in needles, bark, buds and leaves than the wood in a tree, that's why for sustainability the fast grown hardwood plantations set the harvester to strip bark and leave all the lop and top to fertilise the next crop. It must be a very complicated subject because fly ash is generally only collected in fan assisted burners. The particles are fine and they are mostly formed in the secondary combustion area (from small particles carried over from the fire bed) and apart from being mostly silica (SiO2) which itself is bad to inhale in fine particle (think silicosis and mesothelioma ) they contain alkali metals which lower the silica melting point, so they can form a droplet which being in the secondary combustion area forms a nucleus to attract products of incomplete combustion. These PICs can contain polycyclic aromatic compounds like benzo-a-pyrene the carcinogen know to cigarette smokers and dioxins. Any heavy metals that have species of oxides or carbonates which volatilise at combustion temperatures are likely to become concentrated in fly ash. Most legislation about solid fuel burning comes from long experience with coal and fly ash from that (most ash is fly ash in pulverised coal burners I suspect) is definitely hazardous and cannot be disposed directly to land. I think the same rules apply to fly ash from biomass. I'm sure you also need an exemption from EA to apply any wood ash from a commercial biomass burner to land. I've been out of dealing with commercial biomass boilers for over 5 years now but my view is that most nasties will be from "contraries" that come in with the chip. Toward the end I noticed bits of pallet, chipboard and even melamine resin in the biomass chip. The reason is simple; the gate fee for disposing treated timber at a licensed incinerator is between £50 and £80/tonne. The rules seem to allow a small % of contamination so if for instance you can get away with 1% contamination of an otherwise clean sample of wood chip and still sell it for £50 delivered in then for every 1000 tonne you gain up to £1300 by losing 10 tonnes of treated wood waste and this will contain the bulk of the copper, chrome, arsenic, cadmium, lead etc. not to mention pvc.

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