Process Gas Treatment

Ethylene oxide removal

maximum efficiency through conversion to ethylene glycol

Our advanced systems deliver a highly effective solution for the safe and efficient elimination of hazardous emissions from industrial gas streams. Ethylene oxide (EO) - a highly reactive and toxic compound - is absorbed using diluted sulfuric acid and subsequently converted into non-hazardous ethylene glycol within a dedicated reaction tank.

How does it work?

1.) Absorption in diluted sulfuric acid
In the first stage, ethylene oxide is absorbed in diluted sulfuric acid. Ethylene oxide is completely dissolved in the liquid phase without the formation of hazardous side reactions. 

2. Conversion to ethylene glycol
In a dedicated reaction tank, the absorbed ethylene oxide is chemically converted into ethylene glycol. This process achieves high conversion rates and ensures that the hazardous gas is safely transformed into a useful product.

3.) Wastewater neutralization
In the final stage, the resulting wastewater is neutralized with sodium hydroxide to ensure environmentally compliant disposal.
System design options:

• Single-stage or multi-stage configuration
  Depending on process requirements, the system can be designed as a single-stage or multi-stage unit. Multi-stage configurations enable removal efficiencies of over 99.99999 %.
• Maximum safety through explosion-resistant design
  Due to the high reactivity and explosiveness of ethylene oxide, our absorption columns can be designed as pressure-resistant and explosion-proof systems to ensure maximum operational safety.

Your benefits at a glance

• Extremely high removal efficiency - removal rates exceeding 99.99999 %
• Safe conversion of ethylene oxide - transformation into ethylene glycol in a dedicated reaction tank
• Flexible system design - available in single-stage or multi-stage configurations
• Maximum operational safety - explosion- and pressure-resistant construction
• Environmentally responsible wastewater treatment - neutralization using sodium hydroxide 

Efficient gas drying with sulfuric acid

advanced process gas conditioning

In many chemical processes, a dry gas phase is essential - whether to prevent corrosion, enhance product quality, or ensure optimal reaction conditions. Our sulfuric acid gas dryers provide a powerful, economical, and field-proven solution for deep gas dehydration.

How does it work?

The process gas flows upward through a packed-bed column or a tray column in a countercurrent direction to concentrated sulfuric acid. Utilizing its exceptionally high hygroscopic capacity, the sulfuric acid efficiently strips moisture from the gas stream. 

The internal packing provides a maximized surface area for intensive mass transfer between the gas and liquid phases, enabling extremely low residual dew points in the treated gas. Depending on your process requirements, the water-loaded sulfuric acid can then be continuously regenerated or replaced. 

Your benefits at a glance

• Superior drying efficiency - consistently low residual moisture, even with highly humid inlet gases or fluctuating flow compositions
• Robust operational reliability - simple operating principle with no moving parts, ensuring minimal maintenance and maximum uptime
• Flexible system design - easily adaptable to a wide range of gas flow rates and stringent residual moisture specifications
• Versatile applications - ideal for sulfuric acid plants and the dehydration of highly corrosive gases such as chlorine, HCl, and SO₂ 

Efficient recovery of hydrochloric acid from HCl-laden exhaust gases

sustainable and economical

Our hydrochloric acid recovery systems enable the efficient separation and recycling of HCl from industrial exhaust gas streams. Utilizing a multi-stage scrubbing concept, the exhaust gas is thoroughly purified while the recovered hydrochloric acid can be reused as a valuable byproduct.

How does it work?

The hot, HCl-laden gas stream is first cooled with liquid in a quencher to protect downstream equipment and establish optimal absorption conditions. The gas then flows through multiple packed-bed columns, where the HCl content is reduced stepwise. Each stage is fed by the discharged liquid from the subsequent stage:

Quencher (first stage):
The hot exhaust gas is cooled with circulating hydrochloric acid, initiating significant HCl absorption. High-concentration hydrochloric acid is discharged from this stage and made available for further use or storage.
 
Second stage:
The pre-cleaned exhaust gas enters the first packed column, where it is further treated with the scrubbing solution from the third stage. Here, HCl continues to be selectively absorbed.
 
Third Stage:
Fresh water is added in the final packed column to completely remove remaining traces of HCl from the gas stream. The resulting diluted hydrochloric acid is fed back into the previous stage, creating a stepwise concentration build-up.

 
Your benefits at a glance

• Efficient hydrochloric acid recovery through multi-stage absorption
• Optimal utilization of the scrubbing medium via countercurrent inter-stage recirculation
• Integrated quencher for precise temperature control and initial separation
• Customizable system design adaptable to various inlet HCl concentrations
• Economical and resource-saving solution due to a closed-loop design 

Efficient removal of hydrogen fluoride in sulfuric acid plants

In sulfuric acid plants, hydrogen fluoride (HF) can occur as an unwanted impurity in the process gas. Our specialized absorption column enables highly efficient separation of HF, minimizing harmful fluorine carryover into the produced sulfuric acid and preventing equipment damage.

How does it work?

1.) Targeted HF absorption
The process gas is routed through a packed-bed column, where it contacts water in a countercurrent flow. In this stage, the hydrogen fluoride is selectively absorbed while the purified gas passes onward.

2.) Effective fluorine elimination
Through this targeted absorption, the HF content in the process gas is reduced to a safe level, ensuring that downstream process stages remain unaffected. This prevents corrosion and contamination throughout the sulfuric acid production process.

3.) Optimal process integration
The system can be individually tailored to the HF content of the process gas and the specific requirements of the sulfuric acid plant. The scrubbing solution flow rate and column geometry are optimally engineered to achieve maximum separation efficiency.

Your benefits at a glance

• Effective removal of hydrogen fluoride from the process gas
• Protection of the sulfuric acid plant from harmful fluorine contamination
• Custom tailoring to specific process conditions and HF load profiles
• Seamless integration into existing plant layouts
• Durable and low-maintenance design ensuring highly reliable operation 

P₄O₁₀ typically generates during high-temperature processes where phosphorus compounds oxidize. In humid exhaust gases, P₄O₁₀ reacts to form phosphoric acid aerosols. These finely dispersed droplets are highly corrosive, posing a significant risk to both the environment and downstream plant equipment. 

Our specially designed separators equipped with filter candles offer a highly efficient solution for removing these aerosols from the gas stream - compact, reliable, and low-maintenance.

How does it work?

The aerosol-laden gas stream is routed through a vessel containing filter candles made of glass or synthetic fibers. Physical filtration occurs via a combination of mechanical interception, inertial impaction, and diffusion. This process reliably retains the aerosols on the filter surface, allowing them to be continuously drained.

Your benefits at a glance

• Reliable separation of ultra-fine aerosols with collection efficiencies up to 99.99 %
• Corrosion-resistant construction ideally suited for highly aggressive media
• Compact footprint perfect for retrofitting or integrating into existing systems
• Low maintenance costs thanks to long-lasting filter candles and easy handling
• High operational reliability even under fluctuating process conditions 

SO₃ typically generates during the production and processing of sulfuric acid or in other high-temperature processes where sulfur compounds oxidize. In humid exhaust gases, SO₃ reacts to form sulfuric acid aerosols. These finely dispersed droplets are highly corrosive, posing a significant risk to both the environment and downstream plant equipment. 

 Our specially designed separators equipped with filter candles offer a highly efficient solution for removing these aerosols from the gas stream - compact, reliable, and low-maintenance. 

How does it work?

The aerosol-laden gas stream is routed through a vessel containing filter candles made of glass or synthetic fibers. Physical filtration occurs via a combination of mechanical interception, inertial impaction, and diffusion. This process reliably retains the aerosols on the filter surface, allowing them to be continuously drained.

Your benefits at a glance

• Reliable separation of ultra-fine aerosols with collection efficiencies up to 99.99 %
• Corrosion-resistant construction ideally suited for highly aggressive media
• Compact footprint perfect for retrofitting or integrating into existing systems
• Low maintenance costs thanks to long-lasting filter candles and easy handling
• High operational reliability even under fluctuating process conditions