Biological Gas Treatment - biogat

Features

For significant reduction of H2S and CS2 waste gas emissions.

  1. Cleaning Efficiency
    +Up to 98% for H2S
    +Up to 90% for CS2
  2. Column units treating 15,000 to 30,000 m3/h each
  3. Low operation costs
  4. Low waste water quantities
  5. Minimum maintenance requirements

In Detail

The BIOGAT process significantly reduces Carbon Disulphide and Hydrogen Sulphide in waste gases out of viscose processes. H2S and CS2 are converted to diluted sulphuric acid, CO2 and biomass. This catalytic decomposition of CS2 and H2S is achieved by micro-organisms which are immobilized at a carrier layer (saddle packing).

The gas passes four treatment layers inside the column. Each treatment layer reduces the H2S and CS2 concentration in the gas by a certain amount so that the desired cleaning efficiency can be accomplished at the end.
Moisturizing by spraying water is required to keep the biomass in proper conditions and to wash out the sulphuric acid. In order to keep the acid concentration in the right level a certain amount of make up water is dosed into water system, according to the conductivity.
The biomass acts as a catalyst and is not involved in any chemical reactions.
H2S + 2 O2 => SO4 + 2 H+ CS2 + 4 O2 + 2 H2O

=> 2 SO4 + 4 H+ + CO2

The excess water out of the circulation system is equal to the amount of make up water dosed into the system. Thus BIOGAT technology requires no neutralization within the circulation water system.
The micro-organisms need to be fed by nutrients to keep the biomass working. It is dosed in small quantities according to actual demand.
Due to build up of biomass on packed layers they have to be cleaned annually.
The BIOGAT process is particularly suitable for cleaning of low concentrated exhaust gases from Viscose industry, from plants producing pesticides and the like.

Reference plant:
CASE TECH, in WALSRODE, GERMANY
treating 66.000 m3/h with 400 mg CS2/m3 and 100 mg H2S/m3 in four columns. CASE TECH's BIOGAT plant is in successful operation since 1994.

Efficiency:
H2S up to 98%
CS2 > 90%
Projects:
BAODING, CHINA
100,000 m3/h
H2S up to 400 mg/m3
CS2 up to 400 mg/m3
Four columns
FABELTA, BELGIUM
Step 1
Four columns treating 100,000 m3/h
H2S: 57 mg/m3
CS2: 460 mg/m3
Step 2
Six columns treating 150,000 m3/h

Support

For further details about this product group please contact:
visco-tech@lenzing.com