Senseible

Your dye is not a CBAM good. Your buyer will still ask what one batch burns.

For dye and chemical makers in Vapi, Ankleshwar, Vadodara, Ahmedabad and Thane-Belapur

CBAM is the European Union's border carbon check. It covers a short list of goods, and dyes are not on it. Buyers still ask for a footprint per kilogram. It starts with one batch sheet.

Footprint here means the carbon dioxide (CO2) released by the fuel and power you used. Think of it as the smoke behind every kilogram you sell.

Is my product a CBAM good? Almost never.

Only iron and steel, aluminium, cement, fertilisers, hydrogen and electricity are CBAM goods. Ammonia, nitric acid and potassium nitrate count as fertiliser goods.

On the list

Not on the list

If you ship dyes, you need no CBAM data today. European buyers may still ask for a product carbon footprint for their own reports, and for data under Together for Sustainability, a chemical industry scheme. Keep your energy records by plant, so a per-kilogram figure can be built when they ask.

Tick through one batch

Tap the box when a step is done. Watch the line at the top of the sheet. Tap a step's name to read what it means and what a buyer asks.

Example: one batch that gave 2,400 kg of product. kg means kilograms.

1. Charge

Load the raw materials into the kettle. power.

Charging means pouring or pumping the raw materials into the reactor. It is like filling a pot before you cook. Pumps use a little power. This example does not meter it, so it adds nothing to the line.

What a buyer asks

How many kilograms of each raw material went in for each kilogram of finished product, at your real yield, not the textbook one. In a dye, the raw materials are usually the biggest part of the footprint.

Example dye, per kg:

2. React

Heat and stir until the chemistry happens. steam, power.

The kettle is heated with steam from your boiler and stirred by a motor. Chilled brine cools steps that run hot. Steam is your boiler fuel in another form, so its CO2 counts back to the gas or coal you burnt.

Example batch:

What a buyer asks

Steam meter readings and the start and end times in the batch record. Meter readings beat design values. Mark any design value as an estimate.

3. Distil

Boil off the solvent and catch it again. steam, power, solvent.

Distilling boils a liquid and cools its vapour back into liquid, so the solvent can be used again. It is like the lid of a pot dripping. Its steam and pump power count like any other. What you do with the spent solvent decides how the rest is counted.

Where does your spent solvent go?

What a buyer asks

Solvent purchase invoices, recovery logs, incinerator feed records and waste manifests. They also back up the solvent balance some buyers want to see.

4. Filter

Separate the solid product from the liquid. power.

Filtering is a coffee filter for the batch. The product stays on the cloth and the liquid goes through. Pumps use a little power. The liquid left behind is effluent.

What a buyer asks

Where the effluent goes. If it goes to a common effluent treatment plant (CETP) that you do not own, the CO2 from treating your share counts as yours, as waste you send out (buyers call it Scope 3, Category 5). Ask the CETP for its yearly totals.

5. Dry

Take out the last water or solvent with hot air. steam.

Drying is the washing line of the plant, with hot air doing the work. It runs long, so it burns a lot. In Ahmedabad dye units, tray and spin flash dryers take 20 to 36 hours a batch, the longest and one of the most heat-hungry steps. This example does not meter it, so it adds nothing to the line.

What a buyer asks

How you shared the dryer fuel between products, by water evaporated or by dryer hours. Write down which rule you used. Liquid and press-cake products skip the dryer.

6. Pack

Weigh the good product and seal it. nothing counted.

Packing weighs what you can sell. That weight is the number you divide by. A batch that is reworked burns more fuel without giving more product, so it raises the figure, and it belongs in it.

What a buyer asks

The dry weight of good output, the year, and the method. A clear figure a buyer can check beats a polished one.

Recovered here

Count the steam and power of the recovery columns, like any other step. Nothing else is added.

A separate example, one month at a recovery column. It is not part of the batch above.

Burnt in my own oxidiser

Solvent you burn in your own incinerator is counted at the carbon inside it. Add the support fuel from your invoices. This is counted as your own fuel (buyers call it Scope 1).

A separate example, 10 tonnes of toluene burnt. It is not part of the batch above.

Sent to a common incinerator

Solvent waste sent to a common incinerator is counted as waste you send out, using the operator's figure or an estimate you state. This is counted as waste you send out (buyers call it Scope 3, Category 5). Ask the operator for its figure.

Raw materials add far more (example dye: 6.55 kg CO2e per kg in total). This example counts only the reactor's steam and power. Distil, dry and the other steps add what your own meters show.

Which bill sets your number?

Units differ. For some the gas bill is the biggest part of the footprint, for others the power bill. Four examples from regional energy studies. Tap one.

Vapi: A typical dye unit is mostly a gas bill.

A 2020 study of Vapi gives a typical dye and pigment unit about 3,83,000 scm (standard cubic metres) of gas a year for heat, if all heat comes from gas, and about 8,60,000 kWh of power (kWh is one unit on your power bill).

Example, one year:

If your steam comes from coal, use the coal you consumed from your stock register, not these gas figures.

Ankleshwar: Across the cluster, the power bill carries most of it.

A 2020-21 study of 750 Ankleshwar chemical units found 13.31 crore kWh of power and heat from gas and light diesel oil. Power carries about 70 percent of the CO2.

Example, cluster, one year:

The study does not split gas from diesel oil. If all heat were diesel oil, the total would be about 1,36,900 tonnes.

Ahmedabad: In Vatva, gas gives about three quarters of a dye unit's CO2.

A 2020-21 study counted 750 chemical units in Ahmedabad. Most are small. Drying is the first place to look, since it is the longest and hungriest step.

Example, one typical dye and pigment unit, one year:

Thane-Belapur: Bought power is a quarter of the energy, but most of the CO2.

In a 2019-20 profile of the Thane chemical cluster, grid power is 23 percent of the energy and carries about 60 percent of the fossil CO2. That fossil CO2 is an estimated 1,09,000 to 1,12,000 tonnes a year.

Biomass briquettes give 34 percent of the energy. They come from plants, so their CO2 is shown on its own line, not in the fossil figure. For most units, the kWh on the power bill matters more than the boiler.

Keep the batch sheet. Add three lines to it.

For every batch, write down the steam you used, the power you used and where the spent solvent went. Add the year, and the rule you used to share the boiler between products.

A kWh is one unit on your power bill. A clear figure a buyer can check beats a polished one.

Work out my batch footprint per kilogram