Heavy Metal Removal
Calomel Tower
The Calomel Process is a proven wet scrubbing technology designed for the efficient removal of elemental mercury from industrial process gases.
The calomel process for mercury removal
Widely used in non-ferrous metal production and metallurgical applications, the process converts mercury vapor into stable, solid calomel (mercurous chloride), enabling both environmental protection and potential mercury recovery.
Calomel tower process
The process is based on the reaction of elemental mercury vapor with a circulating solution of mercuric chloride (HgCl₂), converting the mercury into insoluble mercurous chloride, commonly known as calomel.
Mercury-containing process gas is introduced into a packed absorption Calomel tower, where it comes into contact with the recirculating mercuric chloride solution. Within the Calomel tower, mercury reacts with the absorbent and forms mercurous chloride, which precipitates from the liquid phase as a stable solid.
A side stream of the circulating solution is continuously directed to a primary settler, where the calomel solids are separated by gravity. The clarified liquid is returned to the absorption system, while the concentrated solids are transferred to a secondary settler for further thickening. If required, zinc dust can be added to enhance mercury precipitation and maximize recovery efficiency.
The concentrated calomel solids are then discharged for storage, recovery, sale, or further processing. Through this continuous scrubbing and separation process, mercury is effectively removed from the gas stream, enabling reliable compliance with stringent environmental regulations while supporting the recovery of valuable mercury-containing by-products.
Key benefits
- High-efficiency removal of elemental mercury from process gases
- Proven technology for non-ferrous metal and metallurgical industries
- Supports compliance with stringent environmental regulations
- Enables collection and recovery of mercury-containing by-products
- Reliable continuous operation with robust process design
- Can be integrated into existing gas cleaning systems
Downloads
GEA Insights
Reality check for biotech
The new GEA Application and Technology Center (ATC) in Sarstedt, south of Hannover, is neither a showroom nor a substitute for a lab. It is a place for testing, data collection and early decisions. This is where it becomes clear whether a biological concept can become a robust industrial process. That step is bigger than it may seem.
Shifts in food packaging: 4 trends
Thermoforming has long played a central role in food packaging. Now it is facing a major shift. As regulations tighten, materials evolve and costs rise, form fill seal lines must do more than run reliably – they now shape how food stays fresh, affordable and recyclable. Take a look at the key thermoforming trends informing the food packaging and delivery landscape.
