Reducing VOC and BTEX emissions for a major Spanish thermosolar company

Compound parabolic concentrators (CPCs) use cylindrical parabolic solar collectors to harvest the rays of the sun. A synthetic organic fluid runs through these collectors, which is crucial for heat transfer. This fluid is a mixture of biphenyl and diphenyl ether, and can quickly reach temperatures up to 400°C.

A negative consequence of this high temperature is the formation of volatile organic compounds (VOCs) including: benzene, toluene, ethylbenzene and xylene (BTEX); naphthalene; diphenyl ether; and biphenyl. To maintain good air quality, it’s crucial to prevent these substances from entering the atmosphere.

This issue may be partially avoided by using an expansion vessel and different separation processes. Even so, emissions still contain VOCs that require treatment.

DESOTEC has the simple and sustainable answer: mobile activated carbon filtration solutions that reduce VOCs to acceptable levels.

The client is happy with DESOTEC’s solution, and is renewing its contract with us for a third year.

Activated carbon is a simple and adaptable technology, capable of treating fluctuating flow rates and concentrations. Therefore, our solutions are well suited to the variable conditions common to thermosolar systems, which depend on the season and level of solar radiation.

We also provide mobile water treatments for thermosolar customers who experience an issue with heat transfer fluids (HTF) ending up in rainwater.

All our filters are mobile, allowing them to be quickly installed. Once the carbon is saturated, the entire filter unit is transported safely away from customers’ sites to DESOTEC’s facilities. There, the adsorbed molecules are destroyed in our furnaces in accordance with national and European legislation, and the carbon is reactivated wherever possible. Only harmless water vapour is seen exiting the chimney. This circular system reduces costs and boosts sustainability, helping to build a greener future for everyone.