Product FAQs – Flamite

Have questions about coal supply? Flamite’s comprehensive FAQ page provides insightful answers to frequently asked questions on coal products, categorization, storage, and more. Whether you’re a seasoned industry professional or new to coal procurement, this resource empowers you to make informed decisions about your coal supply needs.

How much steam will 1 ton of coal produce?

It depends on boiler efficiencies. 1 ton of A Grade Coal ( 27.5 CV) could produce approximately 8 tons of steam, 1 ton of B Grade Coal (26.5 CV) could produce approximately 7.4 tons of steam.

How clean is coal really? Wouldn’t I be better off using electricity, gas or HFO?

As electricity is typically generated from coal fired plants, using electricity simply moves the emission site from your factory to the power station. Gas is known to be a cleaner but more expensive option and HFO is also expensive and typically emits a much blacker smoke from the stacks.

Do coal stacks burn black?

If the boiler is maintained regularly and set up correctly for the coal type being burnt then the stack should burn clear.

Aren’t all boilers designed to use A grade peas?

Coal fired boilers used to be designed to burn A grade coal as it was both affordable and readily available in the past. Nowadays many different grades and types are burnt very successfully in different boiler houses around the country.

What is a Rand per gigajoule and why should I know about this?

The energy in coal (Calorific Value or CV) is measured in megajoules so if you divide your delivered price by the CV you will get your Rand per gigajoule. This is a truer reflection of the cost to procure the energy contained in the coal than simply comparing delivered process across different coal sources.

Isn’t all coal the same?

No coal is graded according to its energy content (CV) as well as its size. An A grade coal has a CV higher than 27,5 MJ/kg, a B grade between 26,5 -27,5 MJ/kg, a C grade between 25,5 – 26,5 MJ/kg etc. A common misconception occurs when people discuss “export quality coal”. Richards Bay Coal Terminal typically exports 2 different grades measured at 6500 kcal/kg and 5500 kcal/kg. This equates to 27.21 MJ/kg (a B grade) and 23,03 MJ/kg (an F grade). To convert kcal/jg to MJ/kg multiply by 0.004187.

What would we need to take into consideration when designing a coal bunker? Type of trucks, size specification, space constraints etc. What are the options?

When designing a bunker the main considerations are how must stock the company needs to hold at any one time, the type of access available to the bunker site and the size of the trucks the company would like to receive (all measurements of trucks can be obtained from us).

Can coal be stored out in the open or does it have to be contained?

Coal can be kept on an open stockpile / area as it will not lose any of its value / properties if exposed for short periods of time.

How long before coal loses some of its properties (CV,VOLS etc) if sitting too long on a stockpile, should coal be rotated?

Coal can lie dormant and without protection from the weather without surrendering any of its properties. The main concern is spontaneous combustion that can occur in long standing piles (typically in smaller sized product with higher volatiles). This is really only a concern in long held stockpiles that would typically only occur in a suppliers depot (such as ours) rather than a client’s bunker. We don’t advocate moving piles due to degradation of the coal size but do recommend that stock is rotated as received.

How is coal categorized in terms of sizing? Terminology?

Duff( 0mmx6mm)
Grains (6mmx12mm)
Peas (6mmx25mm)
Small nuts (20mmx40mm)
Large nuts (40mmx60mm)

These are typical sizes but do vary slightly depending on the mine.

What happens when you wet coal?

The water aids combustion and also ensures that more smaller particles are utilised as they tend to stick to the larger sized coal when wet.

Should coal possess duff (fine) content, and if so, what is an acceptable percentage?

All coal will possess a certain amount of fines content due to handling during processing and loading. The amount is determined by the HGI (hard grove index or hardness) of the coal seam that is being mined. An acceptable norm is 5% of the gross weight.

How do we dispose of ash in the correct manner?

Ash needs to be disposed of in an environmentally responsible manner. There are companies that specialise in ash removal. Please discuss this with your rep should you require further information.

What are the benefits of using a higher grade coal versus cheaper alternatives and the impact this would have on my boiler in the long run?

Using a higher grade coal will not necessarily ensure better efficiencies as compared to a lower grade product as boiler settings are all important. In a perfect world with perfect settings, consumption of a higher grade coal will be less and maintenance spend on the boiler should be reduced. Boilers that are functioning above an 80% output should consider using higher graded products to optimise their efficiencies as these tend to drop off when the demand on the boilers exceeds this threshold.

How often is coal analysed and how often can the test results be made available to the client?

Coal is tested daily on the mines and remitted to us on a monthly basis. These reports can be made available on request. We also conduct random independent testing to ensure that the mine is complying with the specification provided.

What control measures do you have in place in terms of back up and quality?

Our Flamite Cato Ridge depot acts as a back up to our KZN based clients – we have the capacity to store 20 000 tons of coal at any one time.
Our clients in other provinces have peace of mind knowing that we draw from a number of sources and have many trucks on the road at any one time to ensure that we can reroute should you run into an emergency.
With the sheer number of mines and suppliers on our books, there is no need to have the added overhead (and cost to our client) of a depot Gauteng as any number of sources can be drawn on as an when required.

Is coal beneficiated around the boiler spec or are boilers designed around the type of coal that is available?

Boilers are designed according to the clients requirement for steam and also around the type of coal that is available and that can be utilized. Basically, boilers designs are done taking into consideration the type of coal that is actually available.

What is the process of obtaining a license for putting up a new boiler?

Please contact one of our reps who would be happy to assist you in this regard.

Don't see your question answered? Contact our experienced team for expert advice on your specific coal supply needs.