Biomass

Notes from Ed:

Hi sorry I havn't been following all of this thread, but I thought this might be of interest to somebody,

I am a market gardener, I produce a steady stream of biochar from my water heating systems. I live in Wales, it is cold and wet here and I like washing in hot water.

I have played with bringing tlud stoves indoors but it is not easy and so I have built water heating systems using what I call biochar rocket stoves (sorry if this brings back bad memories Crispin!)
Because they are not filled, lit and emptied from the top they can easily be left in place under heat exchangers, hot plates and a flue outlet pipe. Here in Wales this is important.
If you run them in the evening, when you most need space heat and cooking, then after a couple of hours you have your biochar. It is fine to keep them burning for as long as you want (whereas there is a limit to how much you can keep topping up a tlud)
Unlike wood burning stoves, it is possible to have the flue outlet angled up about 30 degrees from horizontal and surrounded in a thermal mass to capture residual heat. Otherwise the 8th photo is of a section of flue outlet with integral thermal mass.
Shut a door on the front and the biochar goes out overnight. My CO meter has yet to read 1ppm indoors. Empty the biochar by sliding out the floor of the stove and it drops straight into a metal bucket, no quenching, no dust and no mess.
The first photos are of these stoves connected to a 50 litre water tank + hotplate and oven for cooking. (The pipe in the second picture is to give secondary air to the flames.) The system in these photos is mobile and connected to a small header tank so that I can do demos at permaculture conventions and workshops.
The youtube video link below is of something different; a double walled flue pipe with feed and empty hoppers for putting in biomass and emptying out biochar. A bit like an anila stove except the inner combustion pipe has no floor, it goes straight through to the stove below. If its ok with Crispin, I was thinking of calling this flue pipe an anila flue pipe.

http://youtu.be/MTiSTrdYuoA

Lighting Cone on the Keren Stove no smoke 1 min after lighting
Anglo Supra Nova Stove
Loading the Anglo Supra Nova Stove
Good Fit for Cone Lighting
Lighting Cone on the Anglo Supra Nova
Handles get hot on lighting cones - make them large

Lighting Cones can help make traditional and charcoal stoves light more efficiently and with less smoke than other lighting methods. For the best detail, download the Masters thesis pdf from Kathleen Lask

From Crispin Pemberton-Pigott's Description:

"The main principle is that there should be enough draft to light the fire rapidly. The lighting cone provides this if it is about 500mm tall."

"The second principle is that the bottom of the cone should sort of cover the lighting fuels so that most air is pulled from below, not from the side."

"The third principle is that if there is a secondary air supply at of just below the top of the fuel, the bottom of the cone should bypass it so that the heat inside the cone is not used to pull air through the secondary air ports. Very few stoves have a secondary air controller."

In the result with good fit: "You can just see on the left that it bypasses the secondary and draws all air from below, through the fuel – in this case charcoal. Peter Coughlin reports it reduces the charcoal ignition time by more than ½. We will quantify the smoke reduction and GERES way independently confirm it at some point – it is about 90%."

Lighting stoves can also be used with traditional fires. In tests lighting damp wood in Suba Island "The speed of ignition and reduction in smoke was dramatic. You can just see the hot air distortion of the picture above the cone – basically no smoke. It is quite a bit cleaner than the fire when lit and the cone removed."
The cone on the 3 stone fire is 125

The Stove in the top example is an Anglo Supra Nova.
"It was developed at YDD during the World Bank/Indonesian Clean Stove Initiative."

"It as an Anglo Supra with preheated secondary air. It can burn wood or charcoal, and it can burn wood pellets in TLUD mode. It can automatically switch from pellet burning TLUD pyrolyser mode to char-burning mode by using a disc of paper on top of the grate."

"The loose piece of clay is a door which can close the primary air without affect the secondary air. It provides a significant level of power control without adding or removing fuel. The heat transfer efficiency burning charcoal (it is nominally a charcoal stove) is about 50%. It Is portable with handles and sells retail for about $5.50."

Kathleen’s investigation is attached.

Regards
Crispin

Removing Handles
Cutting the Throat Hole
Cutting a Top Hole
Internal Elbow
Sheet Metal Held in place with Vermiculite

Nothing fancy but more on the same theme

M Trevor.

Flip Anderson, Haiti Rocket Stove
Aprovecho StoveTec
Mayon Turbo Rice Husk Stove
BioLite Camp Stove
BioLite Camp Stove in Christa Roth's Demonstration House

(Thanks to Ben Sloan!) the presentations are posted on the ETHOS website: http://www.vrac.iastate.edu/ethos/proceedings2013.html

Save the Date!: ETHOS 2014, it will be at Northwest University in Kirkland, Washington on January 24 - 26, 2014.

Jiko Bomba, load the lower half with pellets
Jiko Bomba Gasifying the Pellets and making char
Jiko Bomba, blue flame showing gasification
Jiko Bomba, lower chamber, where charred pellets can be used for low temperature Cooking

Here is some pictures of the Jiko Bomba casification cookstove.
The first shows the two part of the stove with pellet as fuel in the firebox before fire is lit.
Second show the stove burning.
The third the same, in the end of the gasification.
The forth shows the charcoal stage where the pellets remains as glowing carbon. A pot can be put on top of the bottom part of the stove, there are three supports for that.

Yours
Bjarne Laustsen

Here is an example (hard to see of course because it is a still taken from a video) of the spinning of the flame caused by the shaped grate at the bottom.
The fire is circular because it is spinning rapidly, though pushed to the side by the way the fuel happened to be sitting. The spin adds turbulence without a fan and assists in keeping the flame away from the combustion chamber wall.
Here is a really cool picture of a Vesto burning walnut shells in TLUD mode.
Finally, here is a photo of a Vesto cutaway showing the inside parts in their correct positons.

Dear Marc and Ron and All interested in air flows

This is a response to questions about air and Marc’s tube.

Here is an old photo of secondary air entering the combustion chamber of a Vesto pushing the flame to the centre. This accomplishes the following:

Keeps the fire away from the wall, reducing the temperature it has to survive (a lot)
Keeps the flame going
Not allowing it to spread to one side away from the smoke on the other side that might otherwise ‘get away’.
Provides turbulent mixing of flame, hot secondary air and smoke
Allows for preheating to a significant degree (250-500 C)

The fire is circular because it is spinning rapidly, though pushed to the side by the way the fuel happened to be sitting. The spin adds turbulence without a fan and assists in keeping the flame away from the combustion chamber wall.

Here is a Vesto burning switchgrass pellets operating as TLUD, showing that there is nothing special about a TLUD in the sense of it having to operate in a particular fashion. The air flow through the fuel is reduced by the fuel and it operates as a TLUD. The secondary air is send across the surface to keep a deck of flame going at the height of the holes. This obviates the need for adding a circular disk at the top to ’keep the flame going’. Adding a ‘concentrator’ as Paul calls it takes more material and moves the fire too far away from the heat of the pyrolysis bed leading to unwanted flame-outs from time to time. A major issue with all pyrolysing TLUD’s. It is simply not necessary. Just keep the fire near the fuel. This also provides additional vertical space for the flame to finish burning before getting to a cold pot surface.

Finally, here is a photo of a Vesto cutaway showing the inside parts in their correct positons.

The primary air controller is the ring with holes in it. When the handle is moved to the side the holes are closed.

Christa Roth's excellent report
Micro-gasification: Cooking with gas from dry biomass

has a new location:
https://energypedia.info/wiki/File:Micro_Gasification_Cooking_with_gas_f...

Her comprehensive survey of micro-gasification technology has great technical information and is well worth the read.

thanks to GiZ (the German people) for making it available to all of us.

PelletMaker PM 75E  PM 44E, PM 22E

EcoWorxx in Germany is selling a line of pellet makers that take materials from dry, chopped fuel to complete pellets that are suitable for use in stoves and other applications.

Institutional Stove Solutions - InStove

Aprovecho's larger stoves - the instiutional stoves group, have now branched out and become

Institutional Stove Solutions (inStove)

http://instove.org/

They are using the same rocket stove, and have perfected a 60L stove for institutional stove.

They are focusing on schools and other institutions, and have attached an autoclave for hospital and clinic use.

They've found a way to do "Stove factory in a Box", and have perfected a way to build the stove with local labor, and with all tools provided in the factory box and requires only a small generator to operate long term.

A Geyser, is a hot water heater in South Africa. There are many houses that are not connected to conventional utility grids, and heating water with electricity and natural gas is expansive and/or impractical.

Tankless, batch hot water heaters directly connected to the shower etc, are a great single-use application for an efficient stoves.

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