The C.I.S. COMBER Inerting System is designed for the operation of equipment whose internal environment is classified as Group II 1 G and/or D (Gas Ex Zone 0 and/or dust Ex Zone 20) per guideline 94/9/EC. Category 1 G (Ex Zone 0) applies for an environment in which an explosive atmosphere consisting of a mixture of air with flammable substances in the form of gas, Vapour or mist is present continuously or for long periods or frequently. Category 1 D (Ex Zone 20) is the equivalent for explosive or combustible dusts.
The limits of pressure and temperature of applications are: 500 to 1100 mbara and –20/+70 °C respectively.
Machines suitable for operation in such an environment require a very high level of protection against ignition. Using intrinsically safe Ex ia rated instrumentation provides protection from potential electrical hazards (sparks or hot surfaces). Other possible sources of ignition are electrostatic effects and frictional sparking, which cannot be prevented entirely, therefore a safe operation of equipment with an internal explosive atmosphere is not possible.
The equipment thus has to be designed to prevent explosive conditions from building up and to assure the equipment is operated always with a fully inert i.e. safe internal environment.
The C.I.S. COMBER Inerting System has been developed to meet these requirements and has been certified as a “Safety Device” per the 94/9/EC Directive by Company Ineris with certificate no. 05 ATEX 0009.
Diagram of the C.I.S. COMBER Inerting System
The system is designed to provide for inerting of the vessel when the process is working with product and to monitor the inertness of the atmosphere during equipment operation using an oxygen analyzer. Inerting is initiated when oxygen levels at or exceeding 3% are detected. At vessel pressures of 500 or 1100 mbara out of the ATEX limits, the system is put on standby.
The C.I.S. COMBER Inerting System comprises a redundant oxygen analyzer and the relevant engineering documentation as well as the ATEX certificate.
The oxygen analyzer and its sampling path with dual low sample flow switches are fully self monitoring, a feature differentiates between low oxygen concentrations and a dead oxygen sensor, calibration is fully automatic.
SIL 2 approved Inerting Control System
Meets Category 1 requirements for hazardous applications.
Can be applied to the OEM or end user application.
ATEX approved as a Safety Device.
Full FMEA calculations.
Inerting System based on Oxygen and Pressure measurements.
