H.U.T. provides solution for harmful roasting emissions


H.U.T. is passionate about its solution to produce catalysts to reduce harmful waste gases, aggressive smoke and unpleasant odours associated with coffee roasting. The result is happier local authority, local neighbourhoods, and environment. 

Not everyone smells the aroma of freshly roasted coffee with delight. For Julia Heuwieser, Managing Director of Germany-based manufacturing company Heuwieser Umwelttechnik GmbH (H.U.T.), it’s often a sign that something is going wrong.

“The smell of coffee indicates that harmful emissions are escaping. When you have odour and smoke, we know that polluting gases are coming out also,” she says.

Heuwieser has been the Managing Director at H.U.T. since 2015, but she grew up understanding the problem represented by the smell of coffee.

Heuwieser’s father Bernd established H.U.T. in 1995, manufacturing catalytic converters to reduce harmful and polluting emissions from industrial factories.

Heuwieser recalls growing up alongside the business, helping out as a teenager, and working with her father during school holidays.

“I’ve been involved in the company since I can remember. It started out supplying catalytic converters to mainly German-speaking areas, like Germany, Austria and so on, but over the years it’s grown to have customers on every continent,” she says.

Demand for the catalytic converters has expanded dramatically, alongside the global understanding of environmental protection and sustainability.

“Roasting coffee beans primarily creates hydrocarbons, carbon monoxide and nitrogen compounds, which escape into the atmosphere as gases,” Heuwieser explains.

These gases are what Heuwieser focuses on when she visits her clients, who include major roasters around the world looking for ways to shrink their emissions.

Many employ H.U.T.’s catalytic converters as a solution. At the catalyst, chemical reactions lead to a significant reduction of harmful emissions before they can escape into the atmosphere.

“Larger roasteries, who might have a processing volume somewhere around 500 kilograms a day, face similar government restrictions to any other large industrial processor,” Heuwieser says.

“Unfortunately, roasting coffee does inevitably create certain emissions. Simplified: The more caffeine and the darker the roast, the higher the concentration of emissions.”

For example, the caffeine in coffee beans contains nitrogen compounds, which form nitrogen oxide (NOx) gases when roasted.

Nitrogen oxide is classified as a poisonous gas, which is why it is now specifically regulated in many jurisdictions around the world.

“That said, there are many factors in the real emissions we see besides bean variety. If you have a slow roasting process that takes 15 minutes or longer, there is a lower concentration of emissions,” says Heuwieser.

This means roasters who focus on slower, lighter-roasted coffees are likely to produce fewer harmful gases. Companies who look for an intense, dark bean, or simply the volumetric advantage of faster processing, need to account for correspondingly higher emissions.

H.U.T. offers customized solutions for all scenarios – adapted to the roaster’s size, the roaster type, the capacity and the roasting profile. Its catalytic converters – as the name suggests – convert harmful gases just as required in the specific context.

The catalytic converters are placed between the roasting chamber and the chimney to create a chokepoint that gas emissions must pass through before escaping outside.

Set-up is straightforward, “like sliding in a drawer,” says Heuwieser, noting that H.U.T. generally ships its catalytic converters straight to clients with basic installation instructions.

The part which requires particular know-how and experience comes well before the catalytic converters are posted or shipped: H.U.T.’s trained engineers evaluate current emissions in the light of requested limits. Based on that, the catalytic converters are tailored in order to meet specific client needs. All products are fully manufactured in the German headquarters.

“Different countries, and even different regions within a country, can have very different regulations for allowable emissions levels, and they can change quite quickly,” says Heuwieser, noting that within most European countries, those having a roasting capacity of at least 500 kilograms per day are legally required to take measures against emissions. However, there is no common standard.

“Nitrogen compounds weren’t even on the radar until recently, but now they’re a big focus of emissions reduction efforts.”

H.U.T. translates its clients’ legal responsibilities into precisely tailored systems, creating custom catalytic solutions to bring monitored emissions in line with regulations.

“Typically, for reducing carbon monoxide, hydrocarbons, coffee smoke and odours, we recommend our oxidation catalysts. For additionally reducing NOx, the H.U.T. Tandem System is the preferred solution.” Heuwieser says.

The results speak for themselves. For example, a European roaster with a capacity to roast 3000 kilograms per hour, reduced its volume of hydrocarbons by 95 per cent, equalling 17.6 tonne less hydrocarbons per year – just by means of a catalyst. Heuwieser says those with a catalyst can also lower carbon monoxide output by 95 per cent, equalling 21.6 tonne less carbon monoxide per year. With the H.U.T Tandem System, users can save an additional 2.8 tonnes per year of nitrogen oxide.

Based on their long-term experience, the H.U.T. team offers individual advice on how to reduce emissions. They support their clients even after their catalysts have been installed, especially in order to ensure that their products last as long as possible – but also if requirements change and the solution needs to be adapted. Generally, catalysts are low-maintenance, have a long lifetime and are easy to integrate, irrespective of the roaster’s particular set-up.

“We do see some younger specialty roasters just getting started who are very aware of sustainability and want to design their production around a low-emissions, low-footprint standard.”
Those are the companies that go above and beyond current legal requirements, often pitching their products squarely at niche coffee markets to find invested and environmentally aware consumers.

While more and more businesses focus on sustainability, Heuwieser believes that also global legislation will impose further emissions reductions on the coffee industry.

“There is so much attention on sustainability in nearly every country as well as on a global level, and in my personal view that will lead to even stricter standards,” she says.

“The entire coffee industry is very aware of sustainability and the effect emissions have on the environment.”

There are less dire reasons than environmental protection to keep an eye on a roastery’s gaseous outputs. In residential areas, neighbours may not be enthusiastic about the robust aromas achieved by their local coffee roaster.

This might not be a concern for facilities in entirely industrial environments, but H.U.T. is seeing an increasing number of neighbours complaining about smells and odours in mixed residential zones.

“I don’t know if it’s a global trend, but I am seeing more and more clients who have received these kinds of complaints,” says Heuwieser.

To avoid such neighbourly confrontation and contribute a more considered environmental plan, Heuwieser encourages prospective customers to speak to H.U.T.’s experienced team about the best options to suit their needs, hopefully resulting in an even more informed and sustainably-conscience future of coffee roasting.

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This article was first published in the May/June 2022 edition of Global Coffee Report. Read more HERE.

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