Fly ash in. Potassium and silicon out.

This page describes what physically happens to a tonne of bio-fuel plant fly ash after it reaches VAN. Ten tonnes of ash yield roughly one tonne of potash. The potassium route is running and feeding our own plant — about 20% of the potash we use — and we are building it to 500 tonnes a year by 2027. The silicon route is finishing R&D. The process route itself stays proprietary, and the figures we do not yet hold are tagged rather than guessed.

Potassium: in production · scaling up Silicon: R&D — final stage Heavy metals screened by PCSIR

Two nutrients, two stages

We do not average the two into one status. Potassium is in production; silicon is not. A reader deserves to know which is which before reading the process.

Potassium (K₂O) — in production, scaling up

We recover potassium today and consume it inside our own manufacturing, in place of imported potash. It is a working raw material, not a trial — it covers about 20% of our potash intake. The pilot line has processed 3,000 tonnes of ash; the production line we are building takes 5,000 tonnes a year to 500 tonnes of potash by 2027. More than 1,000 tonnes of imported potash has been replaced between 2023 and 2026, across several forms and grades.

Silicon (Si) — R&D, final stage

We have taken the silicon route to the final stage of R&D. It is proven in our laboratory and is being readied to join the production line. The target form is not fixed yet — soluble silicate and amorphous silica behave differently in an alkaline soil, and we will name the form when the R&D settles it, not before. Scale-up to the production line is planned for the end of 2027.

Ten years from a question to a commercial batch

This route was not bought in and it was not quick. It started with a question from a bio-fuel producer and took a decade to reach a saleable batch. We publish the two dates we can date, and the intervals between them as intervals — we have not converted the gaps into stamped years.

When	What we did	What it settled
2014	Answered a question from a bio-fuel producer — what happens to the ash their boilers leave behind. That question, not a research grant, is where this route begins.	The problem was named. Nothing was recovered yet.
The next seven years	Ran the chemistry before the engineering. Characterised feedstock types and their analyses, mapped ash chemistry batch by batch, profiled the impurities, and worked out which grades of ash were worth touching at all.	Seven years before the first batch of fly ash landed with us as a working input.
Two more years	Built the extraction technology and its configurations — turning a characterised feedstock into a route that recovers potassium repeatably rather than once.	A process, not a laboratory result.
Late 2023	Produced the first commercial batch.	The point the route stopped being development and started being production.
Late 2023 → today	Produce, measure, adjust, produce again. The line has been on a learning curve since the first batch — yields, impurity handling and configuration have all moved since late 2023.	In production and still improving. The journey continues.

Production site is not published. The dates above are VAN's own record of the route's development; they are not third-party verified.

Where the recovered potassium goes

It enters the same potash stream every other kilogram of potash enters. That is the answer, and it is why the recovered potash carries no per-grade list.

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Into the shared potash stream

Recovered potassium is blended into the potash VAN draws on across its manufacturing. It is not ring-fenced for one grade, so in practice it reaches every potash-containing product we make.

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No per-grade split to publish

Because the stream is shared, a claim that a named grade "runs on recovered potassium" would be an accounting choice, not a measurement. We publish the intake share — about 20% — and stop there.

This is why no VAN product page carries a "made with recovered potassium" mark. The material is real and it is measured at intake; attributing it to one bag rather than another would not be.

What form the recovered potassium takes

We recover potassium in both liquid and solid form. Which one a given batch becomes is a manufacturing decision, not a fixed output of the process.

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Liquid and solid, both

The recovery route yields recovered potassium in either form. Both go into VAN's own manufacturing as raw material.

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The conversion is not fixed

Today the split follows what our internal process needs. As we scale past our own demand, we will produce the form the market and the customer ask for. We are not going to pin a ratio to it in advance.

Recovered potassium is a raw material either way. It carries no separate registration and no separate performance claim — the finished grades it feeds carry theirs.

Step by step

#	What we do	Why it works	Status
01	We source captured fly ash from boilers fired on agricultural residue. 3,000 tonnes processed to date; the 2027 line takes 5,000 tonnes a year.	Combustion removes the carbon and the water, so the mineral fraction — including K and Si — arrives concentrated relative to the raw residue.	IN PRODUCTION 1 UNDER LONG-TERM CONTRACT · 4 IN NEGOTIATION
02	We assay each incoming batch for potassium and silicon before accepting it.	Ash composition swings with the feedstock and the boiler, so there is no single fixed window worth quoting. We trace the crop residue and the burn cycle behind each batch and judge the ash against what that fuel should produce. Batches outside it are rejected rather than averaged out.	RUNNING
03	We send the ash to PCSIR for heavy-metal screening before it enters the process.	Ash is a waste stream. A recovered nutrient is only usable if what rides along with it is measured, and measured by someone other than us — PCSIR is a government laboratory outside VAN. The screening is against the applicable PSQCA limits, and the report goes out against a batch number like any other certificate.	PCSIR — EXTERNAL · PSQCA LIMITS
04	We extract the plant-available potassium and silicon from the ash body — about one tonne of potash per ten tonnes of ash.	The recoverable fraction is separated from the inert residue so the nutrient can be dosed accurately rather than spread as bulk ash.	K: IN PRODUCTION Si: FINAL R&D ROUTE PROPRIETARY
05	We charge the recovered potassium into our own manufacturing, in place of imported potash.	A recovered nutrient still has to granulate, flow, store and dissolve like the bought-in material it replaces. That is a manufacturing problem, and it is the one VAN already solves across 23 registered products. Which finished grades carry the recovered potassium, and in what proportion, is not published.	IN PRODUCTION — ~20% OF INTAKE GRADE ALLOCATION NOT PUBLISHED
06	We hold it to the same guaranteed analysis as any other raw material we buy.	The finished product's declared N-P-K does not move because its potassium arrived from ash instead of a ship. The incoming material is assayed and dosed to hit the same number.	IN PRODUCTION
07	We are building the line beyond our own demand — 500 tonnes of recovered potash from 5,000 tonnes of ash, by 2027.	Recovery currently sizes to what VAN's plant consumes. Scaling past that is what turns an internal substitution into a supply.	TARGET: 500 t/yr BY 2027

What we measure, and under whose scope

We separate what our accreditation covers from what it does not. Both numbers are real; only one of them is accredited, and we print which.

Parameter	Where it is measured	Scope
Potassium (as K₂O) — every production batch	VAN QC Laboratory	✓ PNAC ACCREDITED ISO/IEC 17025:2017 · LAB 336
Silicon (Si)	VAN QC Laboratory — R&D method, final stage	IN-HOUSE METHOD — OUTSIDE ACCREDITED SCOPE
Heavy metals — incoming ash	PCSIR — external government laboratory, not VAN	EXTERNAL SCREENING · PSQCA LIMITS
pH · conductivity	VAN QC Laboratory	✓ PNAC ACCREDITED (conductivity within the extended scope)

VAN's laboratory holds PNAC accreditation No. LAB 336 to ISO/IEC 17025:2017. We do not extend that accreditation to parameters it does not cover.

What this page claims, and what it leaves open

Carbon: outside this route. Combustion has already released the residue's carbon before the ash reaches us. We recover minerals, not carbon.

Yield: no separate claim. Recovered potassium replaces bought-in potash inside an existing formulation. The product performs as that product performs — recovery changes where the potassium came from, not what it does in the soil. The performance claim stays the product’s own.

The recovered material is a raw material, not a product. It is a raw material inside VAN's own process. It carries no separate PSQCA registration because it is not a separate registered product — the finished grades it goes into carry theirs.

Displaced imports: the held figures, as held. We publish what we hold: 3,000 tonnes of ash processed, about 20% of our potash intake covered, and a 500-tonne-a-year line for 2027. A tonnes-of-import-avoided figure follows when it is one we can stand behind.

Heavy-metal limits: printed when exact. PCSIR screens the incoming ash. The pass/fail thresholds we screen against go on this page when we can print them exactly.

Silicon: final-stage R&D, not yet on the line. The silicon route is at the final stage of R&D. It works in our laboratory. It joins the production line when it is running there, and this page will say so then.

The route is held as a trade secret, not a patent. We hold the recovery process as a trade secret by choice — a decade of feedstock characterisation and configuration work is easier to protect unpublished than disclosed. VAN's patent 144684 covers the sulfur-coated urea process; this route is separate. Where a page says the route is proprietary, it means exactly that.