Steam Hated Vaporizer

Sun Engineering Service manufactures Evaporators for Chlorine, Sulphur Dioxide and Ammonia. The capacity ranges are from 20 kgs/hr to 3000 kgs /hr. Evaporators are classified into two categories depending on type of energy used for vaporizing, namely

• Electrically heated Evaporator Capacity 200 KG/HR MAX
• Steam heated Evaporator Capacity 3000 KG/HR MAX

VAPOURIZER is of heavy duty construction with all pressure parts in contact with chlorine liquid or gas of extra heavy pipe with a minimum of 3 mm corrosion allowance on chlorine side and 1.5mm corrosion allowance on steam side.

Operating principle
In operation the liquid is introduced through liquid inlet which is piped to the bottom of the vapourizer tube by a dip pipe. Here the liquid rises to contact sufficient surface to supply vapour demand rate. After equilibrium is reached vapourizer operates at essentially liquid line pressure As gas demand is reduced. Vapourizer pressure raises, reducing the flow of liquid feed. On sudden shut down of gas valve, liquid Would be forced out of vaporizing chamber back to the container.
With evaporation the vapour raises through the vapour baffle to the super heating chamber. Enters the indicated parts of the suction trap and leaves through the gas outlet.
The steam chamber has nipple connections for steam inlet condensate outlet pressure gauge and pressure relief valve, insulation on shell must be done by the client.

Design Temperature & Pressure for Tube.
The evaporator tube is constructed of specified materials for 64.5 kg/cm² (920 psi ) pressure and 120 °c (250 °f ) temperature. Flanges are of class 300 ( ANSI B 16.5 – 1968 ) and the pipe is of sch 80 (ASA B 36.10 – 1950).

Hydraulics Test Pressure for Tube
102 kg/cm². (1450 psi ) as per ANSI B 16.5 – 1968.

Description of Steam Heated Vapourizer

• Two numbers single tonner connection manifold are provided. When first tonner is getting empty, second tonner line will open automatically through inter lock system for which 3 – way ball valve with electric actuator (8) and pressure switches (6) are installed for auto operation chlorine tonner valve and corresponding valves should be kept open.
• Note :- before admitting liquid chlorine to vaporizer system. Steam shall be admitted first. So that vaporizer body will be heated and ready to receive liquid chlorine. The steam pressure shall be 1.0 kg/cm² unless steam pressure is available in vaporizer steam chamber. Automatic shut off valve (8) on manifold and auto shut off valve (19) on chlorine gas line will not open so that flooding of liquid chlorine is avoided .from manifold liquid chlorine will be fed to vaporizer through dip pipe. As soon as liquid chlorine is fed, gas is formed . please note that chlorine gas coming out will be at least 3 to 5°c above room temperature.
• The chlorine gas coming out of vaporizer passes through chlorine gas filter (16) where all impurities like ferric chloride will be trapped. The filtered gas will pass through automatic shut off valve (19) which is inter locked with pressure switch on steam chamber. As the gas reaches pressure reducing valve where chlorine gas pressure will be reduced from 8 kg/cm² to 0.5 to 3 kg/cm². the outlet of pressure reducing valve is taken to system bye oass valves (17) are provided in case pressure reducing valve is taken for maintenance.

Excess pressure:-
Chlorine vaporizer should be equipped with pressure relief valve to protect the system against rupture spring loaded safety valve are combined in series with a frangible disc ( rupture disc). The rupture disc is 19 to 21 kg//cm² rupture pressure. Because of this pressure relief valve opens when reupture disc burst vent connection shall be taken to chlorine absorption system.

Expansion chamber on liquid chlorine line:
During operation incase automatic shut off valve closes pressure will be developed in liquid chlorine line. In order to reduce the pressure in the line expansion chamber with rupture disc is provided. The repture disc bursts at 19 to 21 kg/cm² and liquid chlorine enters empty cylinder. Because of this action pressure in the line reduces.