The Nuts and Bolts (Mass and Energy Balance) of torrefaction

Over the past couple of weeks, since my last post, I have had more requests for further information than I can recall receiving in the past 3 years.

As a consequence of those enquiries, I have decided to post a detailed outline of our technology, and it's operating prowess. 

It is fair to say that the single most important factor in torrefaction is not the Heating rate - but rather quite the opposite - it's the cooling rate that really matters. As we operate just at the edge of exothermic runaway, controlling the rate at which the reaction develops is critical.

This was probably the single most important revelation in the entire development process.

Most of the requests wanted to look at the "Nuts and Bolts" of our Torrefaction System. The VAST MAJORITY were interested in the performance characteristics of the system. These being:

• Mass Balance
• Energy Balance
• Financial Sensibilities

From an operational point of view . . here are the numbers for our 2-Tonne per hour reactor.

Mass Input = 2790 kg (bone dry)
Mass Output = 2,000 kg (bone dry)
Mass Loss = 790 kg
Net mass recovery = 71.68%
Net mass loss = 28.32%
Feedstock Conversion Ratio = 1.395:1 (dry basis)
Energy In = 52.26 Gj
Energy Out;
Torrefied Fuel = 43 Gj (82.28%)
Tor-gas = 3.95 Gj (7.56%)
Total = 46.95 Gj
Energy loss = 5.31 Gj = 10.16%
System Efficiency = 89.84% (assuming use of Flue Gas for pre-drying) 

Now, from a financial point of view, achieving this level of performance doesn't mean anything - unless it can be done at a price that is sensible.

Our core system, very nicely achieves the $750,000.00 per tonne hour mark. It operates with a 2-man crew, and is capable of sustained performance - 24 hours a day, seven days a week.

Densification, whether into pellets or briquettes is proven, without binders or other additives. In the not-too-distant future, I will be posting a video of the entire system, and it's operation from infeed, through reaction, through grinding, and finishing with pelletisation. I receive a barrel of the product this week, and I have to tell you - it is some of the best bio-coal I have ever seen. Ever particle - from the smallest - to the largest, was a consistent colour and texture. There were no pyrolised pieces, and nor "raw" pieces. 

I have to say that it does my heart good to see that we have finally succeeded in creating a system that is stable in operation, and produces the elusive homogeneous product.Now - It's Onward and upward to the next level. 

RW 

P.S. In answer to the few anonymous requests I have had to publish photographs of our system - we purposely choose not to. There are a number of reasons for this. If however - anyone wishes to contact me, and has a bona-fide reason to learn the intimate details of our technology; to visit and tour our facilities; or to receive sample production runs - then I am happy to share with them on a one-to-one basis.

Unfortunately - there are FAR too many people out there - just on "fishing" expeditions, and we have little time to suffer fools. It's roughly the same as the number of requests I get for "samples" of our product. I dare say that I could keep the shipping department VERY busy if I responded to every request for samples.

Unfortunately - we need to be somewhat selective about who we send this product to - as there needs to be a sound commercial basis for doing so. When you consider that the cost to date of manufacturing this product - is in the tens of thousands of pounds sterling per tonne - you can appreciate that even a kilo of product is very valuable to us. For our Utility and Industrial Partners - for whom we are making hundreds of tonnes - it is a product that they don't particularly want out in the marketplace. Those that have supported us throughout the process - are recipients of this "black gold". Those that now want to just jump on the bandwagon . . . well, I'm afraid without a quid pro quo, the samples and information simply won't be forthcoming.

The last time I checked - we were working on projects in America, Canada, Brazil, South Africa, New Zealand, and most recently - Malaysia. Once these are installed, commissioned and operational - there will be many opportunities to tour the facilities.