About Hydrogen Gas
Hydrogen gas plants with cylinder filling facilities are what we
design & supply to our customers. Either Knowel’s type Mono
Polar Cells or Filter press type Bi-polar cells known as electrolysers
are used for producing hydrogen on a small scale.
The Process
Knowel's Type Electrolytic cells
Production of hydrogen gas through electrolytic Knowel's cells includes
the following process:
- Special quality electrodes are used for the welding of tanks and
bells to avoid em brittling between Hydrogen and Caustic soda.
- C.R.C Sheets are used for producing bells recommended for Caustic
soda handling.
- 100% pure long fiber asbestos without cellulose core are used for
manufacturing asbestos diaphragm cloth. They are closely woven to
avoid pin holes.
- For extra precaution against bye-pass, cloth with extra length is
provided at the bottom.
- High temperature is suitable for testing ebonite insulators
against warping by Meger for infinity resistance.
- Strict supervision is required for anodes nickelling having
minimum of .002 thick coarse deposit. Pores of each plate is tested
chemically.
Details to be taken care
Feed water's quality is the main aspect for maintaining electrolyser's
longevity & great performance. Impurity introduced due to feed water
gets accumulated in electrolyte which consists of chloride, sulphate &
iron. This happens since only hydrogen and oxygen along with other water
vapor escapes from the electrolyser. There impact has a harmful effect
on Nickel metal which leads to heavy corrosion while the latter part's
usage causes impure Oxygen gas.
Electrolysis
|
- Process Description - Electrolysis Process Description
- Producing hydrogen & oxygen are the main motive of the
plant.
- H2O -----1/2 O2 + H2 –
the electrochemical reaction takes place through an electric
current when the water flow enters in the electrolytic cells.
- The produced gases, hydrogen and oxygen, are separately
stored in their proper circuits and tanks.
- The gas is used by the end user as per his requirement. The
automatic supply of the required gases are possible through
generators.
- Production pressure of both gases is > 4 bar, and it is
kept constant by an electronic control equipment.
- Plant Description - Hydrogen Generator Model G 16/d
- Composition of G16/d Generator:
- N.1 Electrolitic Cells including support slide and fixing
belts in inox steel
- Inox steel comprises of all connections and pipelines
- The composition of chassis in painted carbon steel includes:
- In inox steel, the restraining of liquids present in
generator during the emergency is taken care of by “structural
tank" in the lower level.
- The specified tank has painted & fixed carbonium steel
skid which guarantees a complete painting.
- Compartments of 4 varied types used for shell composition
including A-cells, B-transformer C- electrical and electronics
parts D- electro pneumatics devices.
- Internal tanks made of inox steel have functions of bi.
Phasic separators, with condensators with air and liquid
exchangers. Devices necessary for gas treatment, such as
pressures balancing and regulation are all there. Condenses can
be automatically discharged.
- Threaded connection & pipelines in inox steel AISI304.
- The internal exchangers by tube require cooling gases made
available from the separators group.
- N.1 process off-gas discharges device.
- Oxygen & hydrogen processes off- gas of the generator are
discharged externally from the cabinet through a proper
pipeline.
- Plant control instruments
The electronic control panel having proper PLC & power
interface is installed in the front side of the generator, inside a
separate shaft (insulated from production shaft of the degree IP65).
While there is another shaft in the lower level containing the power
transformer.
- Plant performances
- Hydrogen - 10,66 Nm3 / h
- Hydrogen purity > 99, 999%
- Oxygen 5,33 Nm3 / h
- Oxygen Purity > 98,5%
- Produced gas pressure 4 bar (r)
Purity of gases (Knowel's Cell)
- Hydrogen=99.8+ 2 by Vol.
- Oxygen =99.5+ 0.5 by Vol.
Gas pressure (Knowel's Cell)
For storage in low pressure gas holders, a maximum of 250 mm of water
column is required. The unnecessary oxygen is vented through pressure
balancing tank in the atmosphere.
Air Pollution
- (in filter press type) : NIL
- (in Knowel type) : Caustic atmosphere can be, thus, created in
the cell room when minor leakage of gases cant be detected.
Fire Hazards
- (in filter press type) : NIL
- (in Knowel type) :
- Used primarily in loose electrical connection
- Has fair usage in case of blocking of the cells from bottom
due to the disposition of solid Caustic and Carbonate
- Electrolytes leakage leading to short circuit
