jamesbury
APPLICATION REPORT
Chlorine
Liquefaction
Cooling
Water
5
Condenser
4
Refrigerant
Compressor
5
3
Evaporator Liquefier
8
Compressed
Chlorine
Uncondensed
Gas
Liquefaction
Knockout Pot
6
2
7
Liquid
Chlorine
1
Refrigerant
Hold Tank
1
Chlorine Liquefaction
Manual/Isolation Valves
1
3" - 6" (80 – 150DN) 815L 11 2236 XZ
w/ Handle
4
12" - 20" (300 – 500DN) 815L 11 2236 XZ
w/ M Series Gear Actuator
5
6" - 12" (150 – 300DN) 815L 11 2236 XZ
w/ M Series Gear Actuator
6
1" (25DN) 7300C 31 2271 XTZ
alt.
1" (25DN) 9FAC 2271 XT
Automated or Rotary Control
2
3
3" - 4" (80 – 100DN) 815L 11 2236 XZ
w/ QPX Actuator w/ Positioner *
7
10" - 18" (250 – 450DN) 815L 11 2236 XZ
w/ QPX Actuator w/ Positioner *
8
* Positioner can be:
NE Style Electro Pneumatic
NP Style Pneumatic
ND Style Digital
4"-8" (100 – 200DN) 830LC 11 2271 XZ
w/ QPX Actuator w/ Positioner *
alt. Valve
3" - 6" (80 – 150DN) 7300C 31 2271 XTZ
3"-8" (80 – 200DN) 830LC 11 2271 XZ
w/ QPX Actuator w/ Positioner *
alt. Valve
2" - 6" (50 – 150DN) 7300C 31 2271 XTZ1
Chlorine Processing
Liquefaction
Cl2 is liquefied so the material can be safely and
conveniently stored, transported and consumed.
Liquefaction occurs when the previously compressed Cl2
is cooled to a sufficiently low temperature.
Liquefaction is normally a staged process. Normal
practice is to liquefy most of the Cl2 under relatively mild
conditions and then increase the pressure of the gas or
reduce its temperature in stages. Operating stages
at different temperatures often requires the use of two
different refrigerants. For simplicity, a single stage is
shown.
Chlo5 • 8/2011
APPLICATION REPORT
Liquefaction (Con’t.)
Some impurities in the Cl2 gas entering liquefaction are non–
condensable. These leave liquefaction as a vent steam
carrying Cl2 with them. This “tail gas” cannot be released to
the atmosphere. The most common approach to disposing of
the “tail gas” is:
a. Synthesis of a useful product from the Cl2 (HCL, Bleach, FeCl3)
b. Destruction of the Cl2 by scrubbing with alkaline material
c. Enhanced recovery of Cl2 from the gas via absorption /
desorption or enhanced liquefaction
Valve Requirements
Liquefaction is a staged process. Two types of refrigerants are
used. We are showing the first stage for simplicity. The
refrigerant is at 0°F (-18°C) and 30 – 60 psi (2 – 4 bar) valves.
Valves range in size from 3" – 20" (80 – 500DN) ANSI Class 150.
Carbon by 316SS is typical material of construction. Second
stage refrigerants (not shown) are at about -20°F to -40°F
(-28°C to -40°C) and 45 – 75 psi (3 – 5 bar). The valves tend to
be smaller than stage 1. Because of low temperature, 316SS
is required (ASTM352 crade LCB or LCCB is acceptable.)
Metso Solution
High performance Wafer-Sphere® valves with handles or gear
actuators are used to isolate the refrigerant holding tank
(1 ) and condenser. Wafer-Sphere modulation control
valves control refrigerant level (2 ) and pressure in the
evaporator liquefier (3 ). A manual isolation valve is located
in the refrigerant line at the condenser (4 ).
Cooling water to condenser is about 70°F (21°C) and 90 psi
(6 bar). Carbon by 316SS is the recommended material. High
performance Class 150 lugged Wafer-Sphere valves with gear
actuators are used to isolate the condenser from the cooling
water system (5 ).
Compressed chlorine is cooled in liquefiers and transfers to
the liquefaction knockout pot where uncondensed tail gas
leaves the liquefaction process. Located in the tail gas line,
high performance ANSI Class 300 lugged Wafer-Sphere valves
(8 ) of Carbon Steel with Monel® trim maintain compressor
pressure at 45 psi (3 bar).
Liquid chlorine leaves the liquefaction knockout pot. The
chlorine is modulated by a high performance ANSI Class 300
lugged Wafer-Sphere control valve that modulates the rate of
Cl2 consumption (7 ). Carbon Steel with Monel trim is the
recommended material. If the chlorine is going to storage, a
modulating valve may not be required. A 1" (25DN) flanged
ANSI Class 300 Cl2 valve functions as a drain on the knockout
pot (6 ).
Monel is a registered trademark of Inco.
The information provided in this bulletin is advisory in nature, and is intended as a guideline only.
For specific circumstances and more detailed information, please consult with Metso.
Metso Automation Inc.
Europe, Vanha Porvoontie 229, P.O. Box 304, FI-11301 Vantaa, Finland.
Tel. +358 20 483 150. Fax +358 20 483 151
North America, 44 Bowditch Drive, P.O. Box 8044, Shrewsbury, MA 01545, USA.
Tel. +1 508 852 0200. Fax +1 508 852 8172
South America, Av. Independéncia, 2500- Iporanga, 18087-101, Sorocaba-São Paulo
Brazil. Tel. +55 15 2102 9700. Fax +55 15 2102 9748/49
Asia Pacific, 20 Kallang Avenue, Lobby B, #06-00, PICO Creative Centre, Singapore 339411, Singapore.
Tel. +65 6511 1011. Fax +65 6250 0830
China, 19/F, the Exchange Beijing, No. 118, Jianguo Lu Yi, Chaoyang Dist, 100022 Beijing, China.
Tel. +86-10-6566-6600. Fax +86-10-6566-2575
Middle East, Roundabout 8, Unit AB-07, P.O. Box 17175, Jebel Ali Freezone, Dubai,
United Arab Emirates. Tel. +971 4 883 6974. Fax +971 4 883 6836
www.metso.com/automation