Hydrogen Sulfide (H₂S)

Even at low concentrations, H₂S emits an unpleasant rotten egg smell – but activated carbon filtration is an effective way to treat this odour nuisance. DESOTEC supplies solutions for a huge range of common sources of H₂S in air emissions, such as wastewater treatment plants (WWTPs), tank storage, truck loading and unloading, and biogas plants.

We use specially impregnated carbon for H₂S chemisorption. As H₂S is often emitted with other components, you might need more than one type of treatment technology: e.g. scrubbers to reduce the bulk of components, then a DESOTEC filter for the H₂S. Another common set-up is to use multiple DESOTEC filters in series, filled with different carbon grades. Our filters can handle discontinuous flows and varying concentrations of components, making them a highly adaptable option. 

Activated carbon is widely used to remove H₂S from biogas, protecting downstream equipment such as combined heat and power (CHP) machines or the membranes used to upgrade biogas into biomethane. You may require two DESOTEC filters filled with different carbon grades – one for volatile organic compounds (VOCs) and one for H₂S – or complementary technology such as a scrubber. We can advise you on the optimal set-up to meet the H₂S limits set by the manufacturer of your downstream equipment, ensuring efficient operation and cutting maintenance costs. 

Activated carbon filtration is a reliable treatment for H₂S, which is governed by strict legislation due to its toxic, corrosive and flammable nature. Your company must comply with occupational health and safety regulations, odour controls, and environmental legislation to protect air quality and avoid the formation of acid rain. All of these laws might get stricter in the coming years. Plus, you need to stick to manufacturer’s warranties and guidelines for any downstream equipment. 

DESOTEC has the expertise and technology to help you reduce H₂S to very low limits. Our filters can be delivered and installed rapidly to start work immediately in urgent situations, such as odour complaints. Additionally, we handle all waste carbon ourselves in compliance with relevant legislation, saving you hassle. 

Activated carbon filtration is a Best Available Technology (BAT) for many purification applications, and is often the most cost-effective and sustainable option – but it does depend on various factors.

For example:

• Where air flow is intermittent, activated carbon is generally more cost-effective than alternatives such as thermal oxidisers (RTOs).
• If space is tight, DESOTEC filters have a smaller footprint than most alternatives.
• For short-term usage, our filters are mobile and rental – unlike more permanent installations such as RTOs.
• If treatment is needed immediately, our filters can be delivered fast and are plug-and-play – some alternatives have a lengthy lead-in time.
• If your needs might change in the future, our systems are modular – other technology might be less adaptable.

DESOTEC is keen to help customers find the best treatment for their needs, and our experts will tell you if they think an alternative technology might be more suitable than activated carbon.

Activated carbon is a very versatile technology, so there are many ways to optimise set-ups for H₂S removal – e.g. placing two filters in series to treat VOCs and H₂S, or combining filters with complementary technology such as scrubbers.

DESOTEC’s experts carry out testing, advise on set-up design, and offer ongoing support as part of our full-service solution. Our activated carbon filtration solutions have a low total cost of ownership (TCO): they have minimal capex costs, and our service includes maintenance, upgrading, and sustainable carbon waste handling. They enable your business to continue production uninterrupted, and prolong the lifespan of your downstream equipment.

Carbon waste with a high sulphur load requires careful management – and DESOTEC takes care of this for you as part of our full-service solution. Instead of disposal or incineration, we can reactivate this spent carbon safely in our groundbreaking new facility. The carbon produced this way is of the same quality as virgin carbon. Furthermore, we reuse water and heat from the treatment, and recycle by-products such as gypsum for plaster production, making this a highly sustainable and cost-effective process.