UD Technologies > Acid Recovery Plant > Hydrogen chloride Gas Absorber
HCL Gas Adiabatic Absorbers

Hydrogen Chloride Gas Absorber

UD technologies are leading manufacturer of Hydrogen Chloride Absorber or HCl Scrubber in India.

HCl gas comes with other gases like Chlorine, SO2, and inert gases and also organic Chemicals vapors.So, design of Hydrogen Chloride Absorber is tricky.

Our process engineering department understands your process requirement and offer a suitable solution

Hydrogen chloride generates as a by-product or waste gas by a variety of processes like chlorination of Organic chemicals .

In many countries, there are strict maximum emission levels for hydrogen chloride. So,it must be removed from waste gas streams.

Removal achieves simply by absorbing it to produce and recover hydrochloric acid product.


Hydrogen chloride has a great affinity for water .Due to this fact absorption  easily accomplishes.

The absorption of hydrogen chloride into water causes a great amount of heat evolved. This heat has to be removed from the system. The theoretical maximum concentration achievable is dependent on the temperature and the partial pressure of HCI in the exhaust gas entering the plant.

The most appropriate HCI absorption process for any particular application depends on the nature of the feedstock and on the product required.


The three basic types are

  • batch-wise operated HCI scrubbers
  • continuously operated adiabatically
  • isothermal absorbers.

Hydrogen chloride and hydrochloric acid are very corrosive materials and will attack many materials of construction commonly used in the chemical process industries.

Borosilicate glass is the ideal material of construction .

It is suitable for handling hydrogen chloride gas, hydrochloric acid, and any impurities present with the exception of hydrofluoric acid

Hydrogen chloride eventually generates in reaction along with SO2, Unreacted chlorine or organic vapors.

To absorb Hydrogen chloride with such additional chemicals needs different designs and required expertise

Adiabatic Absorber

The Adiabatic absorber is the simplest form of HCl absorber, which can be operated continuously.

Under the normal operating procedure, Adiabatic Hydrogen Chloride Absorber produces 30 % HCl. Adiabatic Absorber is a vertically mounted Packed Column.

The standard configuration of the adiabatic absorber consists of a suitable Glass or ceramic Packed Column with internals, coil type condenser & cooler with the necessary drain outlet for the acid.

The Hydrogen Chloride Gas enters at the bottom of the column & Water flows from the top of the column & flows down through the column.

The heat generates by the dilution of Hydrochloric acid gas with water. It vaporizes water and other non-soluble components of the gas stream. Top condnesers removes heat of absorption by condensing  water.Due to condnesation;bettert abosrption takes place . Condensed stream together with makeup water returns to the packed tower .Hydrochloric acid discharges from the bottom of the column after cooling by cooling water.

The adiabatic absorber is suitable where HCl gas is contaminated with organic Impurities which are to be recovered.

Falling Film Absorber

UD technologies offer Falling Film Absorber  of 10 Kg/hr to 900 Kg/Hr Incoming HCl gas

Process Description

Hydrogen Chloride gas generates from chlorination operation. This must be scrubbed before venting to the atmosphere.

Hydrogen chloride has a great affinity of water and easily absorbed in water.

Falling Film Absorber is Vertical Shell and tube heat exchanger with a suitable device to form the film

The absorption of Hydrogen Chloride gas into the water causes a large amount of heat. To remove this heat at point of Source Cooling water circulates  in the shell  . The remaining un-absorbed gas along with other gases leaves from the bottom enters into Secondary Scrubber. To get maximum absorption ;Process water circulates through Secondary Scrubber to absorb the HCl gas and forms dilute acid.

Tail Scrubber recovers Unscrubbed 5% gases.

This dilute acid is circulated through Falling Film Absorber to absorb HCl gas..


  • High absorption efficiency.
  • High acid concentration is achievable.
  • Safe Operation due to low isothermal temperature.
  • Handle a wide range of gas loading with minimum liquid flow rates to maintain full tube wetting.
  • Variation in Hydrogen Chloride Gas flow rates or Composition causes no operation problem.

Hydrogen Chloride Absorber is tricky in design.

Please give the following details to enable us to offer

  1. Incoming gas Flowrate in Kg per hour
  2. Incoming Gas composition along with Impurities
  3. Available utility

Major Markets

Overall India, Indian Subcontinent, America, Africa

Our other products

Sulfuric Acid Concentration

Sulfuric Acid Dilution

Anhydrous HCl Gas generation Unit ( from Hydrochloric acid)


Interesting Article



If You Need Any Engineering Solutions, We Are Available For You

Contact Us