This design compared to other kilns on the medium scale can reduce kiln cost, save feedstock processing time, can be easily manufactured, is feedstock agnostic, wins on logistics, is more easily assembled and can be adapted to feedstock/Biochar requirements with modular expandable volume.
It's basic panel design and predicted reliable performance could be suitable for generating Biochar Carbon Removal credits from an integrated CRM platform. Read on...

TECH SPECS
- South Australian available steel:
    - 1.55mm (or 2mm) HW350 Corten 'Weathering steel', 1210 x 2440 standard sheets
    - Durable structural steel, weathering for outdoors (can be left assembled), no steel rot
- Standard 'V panel' sides 1150x1150 with 4 x 30mm 90 degree folds
- Standard Panel for Ends, 1160x1180, with 3 x 30mm 90 degree folds, dual prongs for anchoring into soft ground/earth
- both end and side panels will use 25x25x2 square tube 'X reinforcement' using a laser stitch weld (or MIG/TIG) on same side as folds

- optional 'U leg system' per side panel for stable load bearing, also using 25x25x2 square tube with 304 door hinges plus square tube blocks for the upper attachment points and a horizontal base support connecting the 2 legs
- Could have a U shaped 'bolt on' handle central and on top of the top fold for moving a panel around. 'Bolt on' handle can be removed for pallet logistics and is stronger than welds

- Modular/Expandable

    - Volume for base unit (2 ends, 4 side panels, with no truncation is 1322.5 litres) then add volumes per additional V panel pairs (could add truncation to increase overall volume too)
    - length also determined by the length of the biomass feedstock eg.bamboo, hemp straw, kelp et al.
- Weight: 35kg/sheet, so, just under 17.5kg per panel + weight of 'X reinforcement ' (should be OK for Oz Workplace, Health & Safety as there are now no upper weight limits). Heavy but can be managed by one person.

- Panels will fit on a standard 1165x1165 Oz pallet - perfect for logistics

Assembly
- Drop the first end panel in
    - Folds pointed away from the V panels/fuel chamber footprint
    - pound the top of the end to drive the prongs in (with the club hammer)
- pound in 2 star pickets per side, 60cm apart (with the club hammer), lining up with edge of end panel, first one 30cm away
- assemble the sides/V panel pairs
    - first V panel pairs, leaned against star pickets (with optional truncation)
    - 2 steel 'C clamps' per outward facing and sloping adjacent V panel folds for additional stability
- drop in and pound the second/last end panel in, folds facing outwards

Operation
- fill the kiln half full with thin biomass waste
- light at the top (using firelighter gel if you can get it)
- create a bed of coals
- add the first layer
- wait until top ashes a little
- add next layer and repeat until the top of the panel module is full
- flame almost goes completely out
- quench
    - carefully remove one side of the V panels
    - rake out the biochar
    - use water, urine, soil, manure etc.
    
DONE

- add a 'U leg system' to each side panel
 - each vertical leg top anchored at 200mm in from the lateral edges and 100mm from the top
        - 304 door hinges
            - needs a tough weld eg. Stick welding as it would be partly load bearing on leg/hinge

            - attached to galv square tube 'blocks', same tube as legs and 'X reinforcement'
        - for legs, same galv square tube used for blocks and 'X reinforcement'
            - 1050 length
            - 60 degree cut at top end of leg for leg/panel interface and load bearing through the entire leg
            - 60 degree cut at bottom of leg
            - 8mm hole drilled 50mm in from end of leg (through 2 opposite tube sides) for tent peg anchoring

            - 700 bottom square tube cross piece connecting both legs at the base for stability which makes a 'U' shape. Sits flat when U is extended
            - default position for storage or transport will fold parallel to and sit against the panel outer surface

        - pros
            - soft ground (tent pegs) or hard ground (no tent pegs) kiln operation
            - no pounding of star pickets needed
            - more stable than vertical star pickets
            - easier for 1 person assembly compared to no weld Galv legs (possibly wedged under the top folds at 60 degs)
        - cons
            - if truncation needed could use vertical star pickets without using attached legs

Initially, the CRM platform could use manual volume verification while the burn numbers are low and there's enough work time to do it.

How?

- An end/long shot of the kiln, after a burn and before a quench, can be used to
    - count the number of 'V panel' pairs using the top handles as an indicator with the result compared to an app question, 'How many pairs of V panels are used in your burn?' for verification. This can be used to calculate the length of the kiln. If the 'V panels' are at a 60 degree angle, the top width of one pair of 'V panels' will be known. The base width will be zero, without truncation
    - estimate the height of the biochar via an internal central vertical measuring strip on the inner side of the end panel at the far end of the photo eg. galvanised roofing screws equidistant eg.50mm, between each screw

    -a simple calculation can then be performed to determine the biochar volume

https://www.omnicalculator.com/math/trapezoidal-prism-volume

Once the volume of the biochar is known, the mass yield of biochar (17% of volume - need to confirm for the Algorithm) can be calculated that can then be used to estimate C (approximately 85% of mass yield) then CO2 emission equivalents (CO2e) in tonnes removed from the atmosphere/climate system (44/12) which can determine the number of Carbon removal credits paid (per tonnes of CO2e) according to current market value (USD/tonne)
So,
Volume (L) x 0.17 x 0.85 x 3.67
=CO2e in kg removed by a burn(B)
$ per tonnes of CO2e
($ x B/1000)
= Black Gold

What if the kiln is 30 metres long and the long shot can't capture enough detail on the handles? That's where 4k video could be handy for 'Object detection' of the top handles. 

Think of the modelling as an AI 'helper' for determining kiln volume which could one day be automated if, say, 100,000 Algorithm's are out in the field with large numbers of burns to verify.  As competition steps up in the Carbon Removal Marketplace, more secure approaches will be expected for small to medium sized kilns to attract Biochar Carbon Removal credit buyers.

One other point is that standard outer dimensions of the panels, sides and ends, are practical from a standard sheet metal availability perspective and should work exceptionally well with the standard Ozzie pallet and possibly elsewhere for logistics. It will also standardise easy volume calculations, whether it be manual or 'Object detection'. Every other aspect of the Algorithm is open to design interpretation, testing and development eg. steel, panel bracing, handles and legs/supports.

Any feedback on the 'Contact' page on this would be much appreciated...

As the Algorithm is at the build phase of R&D (I'm building one for the 2025 biochar season) this design may need to be modded for future iterations/generations. For eg., I can't guarantee the panels won't warp for a given (?any) feedstock although I have tested 1.55mm Corten panels in the Flat Modular Biochar kiln which were smaller without X reinforcement but did not warp. Any feedstock with a moisture content below 15% is going to test the engineering limits of this kiln. Mistakes lead to more learning, so if you can't wait until I've tested my first one, can access manufacturing and are prepared to lose some money if some/all the panels warp, go for it - but I doubt they will warp. You can always mod the panel(s) design for stronger reinforcement (or for future variations if the initial design fails). There's also a possibility of using thermal cogeneration for power during a burn using a heat exchanger on one end of the kiln coupled to a Stirling engine or ORC.

If we can get a group working on the same tech, it will be much faster R&D. The main bucks will be in kiln manufacturing, kiln sales, possible biomass waste removal service for farmers, biochar sales (or farmer keeps it) by Charistas and Biochar Carbon Removal credits for Charistas. There's also a software angle too.

The Carbon Removal Marketplace idea I am thinking about ATM could be integrated with the Algorithm.

A subscription service or one off payment (with lifetime platform access & support) could be used with no Carbon Removal Credit micro-transactions, which goes against the tide of most CRM platforms I have come across. Basically, SaaS with a decentralised manufacturing Industry 4.0 concept - except, it would be artisanal manufacturing (as opposed to 3D printing) around the world  (local jobs, low logistics C footprint) with initially a non-commercial Creative Commons license used until an 'appropriate' (eg. cutting, folding & welding) and 'standard' (eg. outer panel dimensions and 'Object detection' reference points) kiln design is engineered that can be built in most places, is steel agnostic, and can be integrated with the CRM. If we get that far, then the license will be reviewed, possibly using a commercial Creative Commons license for the kiln.

Initially, a lean team of Python coding volunteers, deep learners and data scientists eg. Uni students, GitHub etc. and Charistas prepared to build an Algorithm and give it a go could build the platform prototype.

What do you think?

If you're interested...please use the 'Contact' form and send me a message and I'll get back to you promptly.

Here's also a link to a blog about flame cap panel kilns on this site:

https://www.permachar.net/2024/08/01/panel-kilns-the-future-of-low-cost-high-volume-medium-scale-biochar-production/