ENVIRONTEC DT dry type desulphurization is a simple, cost-effective and high-efficiency technology for desulphurization at low H2S inlet concentration (<2000ppm). It can be combined with biological desulphurization for higher H2S concentration application for longer operating time and best effect guarantee.
Design for best gas speed Mass inlet and outlet hopper
Mass lifting device and platform
Continuous mass loading & unloading
Temperature and pressure monitoring
High efficiency Mass: Fe2O3.H2O
High efficiency Mass: Active Carbon
The dry type desulphurization consists of a stainless steel tank, desulphurization filling mass, inlet and outlet hoppers, mass lifting device, double air tightness valves and also pressure and temperature gauges. The filling mass can be chosen with Fe2O3.H2O or Active Carbon.
Desulfurization plant is usually designed 1 use 1 standby. The standby tower is put into use when another tower has to be bypassed to change the filling mass completely. Environtec has designed special mass inlet and outlet hoppers with double air tightness valves. This means the filling mass can be replaced continuously everyday or every week with small amount during operation, so that one tower is enough.
When the raw gas enters the bottom of desulfurization tower, H2S react with fill mass (Fe2O3.H2O) with
following the reaction:
Fe2O3•H2O + 3 H2S === Fe2S3 + 4 H2O
Fe2S3 + 3/2 O2 + 3 H2O === Fe2O3•H2O + 2 H2O + 3 S
Or H2S react with Active Carbon with following reaction:
2H2S+3O2 === 2H2O+2SO2
H2S+2O2 === H2SO4
2H2S+SO2 === 3S+ 2H2O
H2SO4+H2S === S+2H2O+SO2
1/8S8 +O2 === SO2
Fresh desulphurization mass is fed into the reactor by a transport vessel which is lifted to the top platform. By adding oxygen, the above reactions of desulphurization and reproduction occur simultaneously. The desulphurization mass is effective until sulfur blocks the passage of biogas with big pressure loss. Then the filling mass has to be replaced.
Environtec has researched and developed the filling mass for years. For example, the ZC-102 filling mass of Fe2O3
reaches more than 30% working sulfur content; and the ZC-103 filling mass is able to treat H2S to 1ppm at outlet.
As an option, Environtec has designed a special oxygen addition system. A small amount of oxygen addition contributes a lot for the mass reproduction, so as to reduce the frequency of changing the filling mass.