Driving Efficiency In Process Industries By Harnessing

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To many, steam power reached its zenith in the 19th and 20th centuries – James Watt’s invention in 1781 of a patented steam engine set in motion the first “golden age” of steam.

That epoch came to an end with the gradual processes of “dieselisation” and “electrification across industries – and it seemed like steam’s day was done.

*Chris Armitage, Chief Executive of Heliex Power*

However, that could all be about to change. A second golden age of steam beckons in the very same place that first made a breakthrough in its mainstream use: Scotland. The results could see businesses that manufacture a wide range of different products improve efficiency, cut their energy costs, and boost their sustainability credentials.

In the town of East Kilbride, just outside of the country’s largest city and industrial hub of Glasgow, Heliex Power has solved a problem that baffled engineers for centuries: how to harness the power of “wet” steam.

It can be surprising to learn that there’s a distinction to be made when it comes to steam – after all, it’s just vapour, and has driven turbines since the 1800s. But there’s a lot more to it than that…

As a simple illustration, take a kettle. When it reaches boiling point, a small amount of almost-invisible, high temperature and pressure vapour escapes from the kettle – or “dry” steam as it’s known. This type of steam, superheated and generally more expensive to produce, has been used in turbines for years.

The other kind of steam, perhaps unsurprisingly given the epithet “Wet”, on the other hand, hasn’t been used anywhere near as much. This is the type of steam you can see emanating from the kettle after it has boiled, full of water molecules that degrade machinery and make it impossible to use.

“We’ve found a way around that”, said Chris Armitage, Chief Executive of Heliex Power. “We’ve developed a robust twin-screw system, our patented Steam Expander System, which will take wet steam without being eroded by water particles. It’s working in areas and conditions that were previously thought to be impossible.”

The technology’s roots sit within the department of mechanical engineering at City University, London. Some of the institution’s top academics, Professors Ian Smith and Nikola Stosic, had been working on the problem for about 40 years, before coming up with the designs for the Steam Expander System.

Recover waste steam between 100°C and 200°C

Their discovery was completely new, making the system a unique proposition for businesses looking to recover waste steam between 100°C and 200°C.

“No one else has a product that can replicate what our system does”, explained Chris .
“The crucial bit that makes it all happen is the screw expander, which has two rotors entwined with each other. The profile of the rotor is the important part, and the two rotors sit within a casing and are supported on bearings at each end.
We expand the steam through that expander and, in doing so, the two rotors turn and we have an output at one end. We connect that to a generator to produce electricity.”

The energy savings that could be made from using lost wet steam from industrial processes are huge. Estimates suggest that more than 40,000 gigawatt hours (GWh) of energy vanishes globally every year through waste steam. Other analyses found that up to 50% of industrial energy usage is eventually released as waste heat – enough to power 28 billion homes.

As the numbers indicate, the potential is huge. Heliex estimates that the potential market for its system is in excess of £70 billion and research from a possible partner in China suggests that a million of its systems are required in that country alone.

The wet steam technology transcends sectors too, with relevance to process industries ranging from chemical manufacturing and dairy processing, to areas such as waste incineration, farming and timber.

“Essentially, added Chris, the technology can be used in any process that uses steam directly or uses a steam system as a heating medium. Its wide range of potential applications and the sheer amount of steam produced by all of these industries means the technology’s potential is vast”.
“When we first ran numbers for market analysis, they were so huge we had trouble believing them. There are so many businesses out there that could benefit from this technology, but the majority don’t know it exists yet.
”Adoption of the technology is picking up, with more than 40 units in the field, clocking up over 60,000 hours of operating time. After booking £900,000 in revenue in 2014/2015, Heliex grew sales to £2.7 million last year. The company expects to double this in 2016/2017, and do the same again during the following 12 months – which translates into a lot more of the systems in action.
“Once they see the economic, efficiency, and environmental benefits, we’re confident more companies will look at how they can make the most of their waste steam, which they’ve been throwing away as waste heat for years”
“There’s a huge amount of it out there that could be put to better use, heating homes and powering industry. It’s a real breakthrough in driving efficiency in a variety of industries and is only in its infancy – there’s still a great deal to come from steam.” Chris concluded.

A glass-ic example…

Milan-based Vetrobalsamo produces more than 500,000 glass bottles every day, putting sustainability first by reducing fume emissions by 70% compared with other traditional glassworks.

The company needed to produce, not only electricity for its factory, but heat energy for the districting heating grid, using energy from the process flue gasses in two furnaces.

While a number of technologies were considered, a Steam Expander System was chosen as the best way of supplying both the electricity for the plant and the correct temperature of heat for the district heating scheme. The system uses steam produced by a dedicated heat recovery steam generator, working at pressure of 20 Bara °C.

One of the first systems to be installed, it generates 400 kW of electricity from the glass-making plant, with the residual 4MW of free heat supplied to local residents.

Thanks to high efficiency and energy-saving incentives, the complete system allows the company to save more than €1 million per year.

And a speciality for chemicals…

One speciality chemicals company with a commitment to sustainable development is taking advantage of its waste steam, a significant amount of which is created in its manufacturing process. The business decided to investigate how it could exploit the wasted energy in its steam.

With its steam raised at 18 Bara and then dropped to 3.3 Bara for its manufacturing processes, the company decided to install two Heliex systems to sit alongside the pressure reduction valve in the existing steam distribution system.

This combination offers the business additional operational flexibility, while retaining the ability to generate considerable power during periods where one of the machines is under maintenance.

The economic benefits have been significant, delivering savings of £122,150 per year and payback in just under three years, while 348.1 tonnes of carbon have also been saved.