The Carbon Problem in Green Sand Foundries
Coal dust has been the default carbon additive in green sand foundries for decades. Its purpose is to create a lustrous carbon layer that prevents metal-sand fusion. But this protection comes at a steep environmental cost.
When coal dust combusts inside the mould, it releases CO, CO2, and volatile organic compounds (VOCs) directly into the foundry environment. The volatile matter content of coal dust (25–40% at 400°C) means a significant portion of every kilogram you add burns off as emissions — contributing to your foundry's carbon footprint with every single pour.
This wasn't a business problem when emissions had no cost. With the EU's Carbon Border Adjustment Mechanism (CBAM) now in effect, the embedded carbon in every casting you export has a measurable financial consequence. The question is no longer whether to reduce emissions, but how fast you can do it.
How Nanokarb Eliminates Combustion Emissions
Nanokarb uses ceramic nanoparticles impregnated into a quasi-graphitic carbon matrix. These engineered nanoparticles form a non-wetting barrier at the mould-metal interface without combustion. The volatile matter content is 0% at 400°C and less than 10% at 925°C.
The result: the destructive chain reaction that coal dust triggers — heat spikes, bentonite degradation, VOC emissions — never initiates. Protection comes from engineered surface properties, not from burning fossil-fuel based carbon. This is not an incremental improvement. It is a fundamentally different mechanism.
Measured Results — European Foundry Trial
Verified trial data from a Swedish foundry melting high Chromium and high Nickel alloys on a High Pressure Moulding Line. 120 MT sand system, 450 MT liquid metal per month, 1600°C pouring temperature. Trial duration: 36 circulations.
67.8%
Reduction in CO Emissions
87 ppm → 28 ppm (measured)
52.7%
Reduction in Carbon Consumption
2.116 kg → 1 kg per batch
13.9%
Reduction in Bentonite Consumption
2.113 kg → 1.82 kg per batch
0%
Volatile Matter at 400°C
Coal dust: 25–40% at 400°C
Before and After Nanokarb
Data from verified European foundry trial, December 2019
| Parameter | Before (Coal Dust) | With Nanokarb | Reduction |
|---|---|---|---|
| Carbon consumption (kg/batch) | 2.116 | 1.0 | 52.7% |
| Bentonite consumption (kg/batch) | 2.113 | 1.82 | 13.9% |
| CO emissions (ppm, weekly average) | 87 | 28 | 67.8% |
| Surface finish | Standard | Superior — immediate improvement | — |
| Sand sticking | Present | Evident reduction | — |
What would a 67.8% emission reduction mean for your foundry?
We use proprietary predictive tools to forecast your exact results before the trial begins.
Calculate Your Carbon SavingsWhat CBAM Means for Your Foundry
The EU's Carbon Border Adjustment Mechanism (CBAM) requires importers to declare the embedded carbon in products entering the EU. For foundries exporting castings to Europe, this means the CO2 generated during your moulding process — including from coal dust combustion — is now a line item on your customer's compliance report.
Foundries that can demonstrate lower embedded carbon will have a competitive advantage. Those that cannot will face either carbon surcharges passed through by EU importers or, increasingly, loss of contracts to competitors who have already addressed their emissions.
Switching from coal dust to Nanokarb is one of the most direct ways to reduce the embedded carbon in your castings — because it eliminates the largest single source of combustion emissions in the green sand process.
CBAM Compliance Support
Our sister organisation, Carbon Without Borders (CminusB LLP), helps foundries compute their carbon footprint, prepare emissions declarations, and navigate the CBAM compliance process. From carbon accounting to documentation, Carbon Without Borders provides the expertise to ensure your foundry is audit-ready.
Visit Carbon Without Borders →Environmental Product Declarations
We are currently developing Environmental Product Declarations (EPDs) and Life Cycle Assessments (LCAs) for our product range. These third-party verified documents will provide transparent, standardised data on the environmental impact of Nanokarb, MouldMax, and Nanocore — giving your procurement and sustainability teams the documentation they need for Scope 3 reporting and supplier audits.
Beyond Carbon: The Full Environmental Impact
Eliminate VOCs
Coal dust volatiles release benzene, toluene, and other VOCs during moulding. Nanokarb's 0% volatile matter at 400°C means these emissions simply don't occur.
Reduce Raw Material Mining
1 kg of Nanokarb replaces 2 kg of coal dust. Less coal mined, less transported, less burned. Combined with 10–15% bentonite reduction, the upstream environmental benefit compounds.
Reduce Foundry Waste
Better sand system stability means fewer rejected castings. Fewer rejections means less scrap metal to remelt, less energy consumed, and less waste generated.
Ready to Measure Your Foundry's Carbon Reduction?
We'll predict your emission reduction before the trial starts — using proprietary forecasting tools. You hold us accountable.
Request a Free Trial