H2S Removal Plant

  • Typical feed: H2S-rich Gas Mixture
  • H2S content: ≤1ppm by vol.
  • Operation: Automatic, PLC controlled
  • Utilities: the following Utilities are required:
  • Electric power

Product Introduction


Iron complex desulfurization has the characteristics of large absorption capacity of sulfur, high desulfurization efficiency, fast speed of sulfur extraction and oxidation regeneration, easy recovery of sulfur, pollution-free desulfurizer, and has been experienced in industrial application.

Iron complex desulfurization process can achieve 99.9% H2S removal rate in many industrial fields, including natural gas extraction, crude oil extraction, petroleum refining, biological gas treatment, chemical sulfur gas and coke oven gas, etc.
In these industrial processes, the gas to be treated capacity from a few cubic meters to tens of thousands of cubic meters, and the sulfur produced every day ranges from a few kilograms to dozens of tons.
The H2S content of the gas treated by the complex iron system is less than 1PPmV.


(1) The H2S removal rate is high, the first step reaction removal rate is more than 99.99%, and the concentration of H2S in the treated tail gas is below 1 ppm.
(2) Wide application range, can deal with a variety of H2S gas.
(3) The operation is flexible and can adapt to the large fluctuation of H2S concentration and flow rate of raw gas from 0 to 100%.
(4) Environmentally friendly, no three wastes produced.
(5) Mild reaction conditions, liquid phase and normal temperature reaction process.
(6) Simple process, plant running/stopping and daily operation are simple.
(7) High economic performance, small footprint, less investment costs and low daily operation costs.
(8) High safety performance, the system does not use any toxic chemicals and the sulfur products are without H2S gas.

Application field

Natural gas and associated gas desulfurization
Acid tail gas desulfurization and sulfur recovery
Refinery gas desulfurization
Coke oven gas desulfurization
Biogas desulfurization
Syngas desulfurization

H2S Removal Process

1, Conventional iron complex desulfurization
When dealing with flammable gas or other useful gas, an independent absorption tower and an oxidation tower are adopt and the iron complex catalyst are pump into the vessel by booster pump. The absorber separates the H2S from the sulfur-containing gas and converts it to elemental sulfur. The oxidation column can recover the iron complex catalyst. The desulfurization and regeneration are respectively carried out in two towers, so it is called the two-tower process.
2, Self-circulating complex iron desulfurization
A self-circulating process can be used when dealing with amine gases and other non-combustible low pressure gases. In this system, the absorption tower and the oxidation tower are integrated into one unit, thus reducing one vessel, and eliminating the solution circulation pump and related pipeline devices.

The oxidation of sulfur

H2S absorption process & Ionization Process – Mass Transfer process – Rate control step
H2S+ H2jt HS- + H+
Sulfur oxidation process – Rapid reaction
HS- + 2Fe3+ jt S°(s) + H+ + 2Fe2+
Sulfur is formed as a solid and form inactive iron bivalent

Catalyst regeneration process

Oxygen absorption process – mass transfer process, rate control step, the oxygen source is air
Catalyst regeneration – Rapid reaction process
½ O2 + 2Fe2+ + H2jt 2Fe3+ + 2OH-