STION IN ETHYLENE PRODUCTION
Continuous Emissions Monitoring Systems ( CEMS ), using the SERVOPRO 4900 9 10 11 12 and Servomex sample systems are used to measure the stack emissions for legislative requirements of O 2 , CO , NOx and SOx . The 4900 can also be installed either side of a Selective Catalytic Reduction ( SCR ) unit to monitor the SCR ’ s efficiency in reducing NOx emissions , while the SERVOTOUGH Laser 3 Plus Ammonia
13 monitors the NH3 level , which is allowed to “ slip ” through the catalysis during the NOx reduction reaction .
On the outlet of the cracker unit a transfer line exchanger ( TLE ) rapidly cools the cracked gas to preserve the gas composition : a SpectraScan and H2Scan
14 monitor the gas quality after the cracking unit , ensuring the highest possible ethylene yield and to prevent undercracking or over-cracking .
After every 20 days or so of operation , the cracking furnaces need to be decoked since they acquire a coating of carbon over time and lose efficiency . This is done by burning off the coke with air in a steam atmosphere .
The progress of the decoking phase is monitored by measuring the amount of CO 2 ( 0-5 %) in the effluent . It rises as the carbon is burnt off and then reduces to zero when the furnaces are clean again , and the plant can be returned to normal operation .
During the decoke cycle a SpectraScan
14 with added CO2 channel can also be utilized to monitor CO 2 levels , as well as to ensure the shortest decoking cycle with real-time analysis , or a separate SpectraExact 15 can be utilized for this measurement .
X
er 3 Plus & CO
00 & NO X
Laser 3 Plus
O 2
& CO FluegasExact
O 2
& CO e
SpectraScan H2Scan C1 to C6 H 2
Common Stack
14 15
10
4900
O 2
, CO , NO X , SO X
SpectraExact SpectraScan H2Scan
CO 2
C1 to C6 H 2
Prolysis Probe
BENEFITS OF TDL TECHNOLOGY
Servomex ’ s advanced TDL technologies offer significant advantages when applied as a combustion control solution for ethylene furnaces , maximizing efficiency whilst reducing greenhouse gas emissions .
The highly robust technique provides reliable measurement of combustion gases with less associated maintenance , while the location of the measurement close to the flame delivers the fastest response , optimizing combustion and minimizing fuel costs .
TDL technologies are particularly suitable for in-situ cross-stack measurements , with a typical cross-stack system consisting of the laser emitter module and receiver mounted across the process pipe line or flue stack .
TLE
AVAILABLE NOW :
The SERVOTOUGH Laser 3 Plus TDL range . See pages 6 and 7 . raScan n C6 H 2
5
We have the solution for HP process - contact your local business center at servomex . com
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