Introduction; General - Michell Instruments Condumax II Installation Operation & Maintenance

Condumax II Sampling System -
NEC Compatible IOM Manual
1

INTRODUCTION

1.1

General

The Condumax II Hydrocarbon Dew-Point Analyzer Sampling System is specifically
designed for the measurement of hydrocarbon and water dew-point in natural gas.
The addition of water dew-point is optional to factory order. The system is configured
with the necessary pressure letdown and flow control required for measurement at
pressure before finally venting to an atmospheric or a low pressure flare line system.
A fast-loop bypass flow arrangement is included to reduce sample flow response time
lag and to enable the filter to be drained automatically of any potential hydrocarbon
liquids and hydrates formed. Tube and process connections are 1/4" OD.
HC dew-point analysis pressure is adjusted by a heated pressure regulator in the
range up to 35 barg (500 psig). However, it is typical for measurements to be made at
the cricondentherm condition of 27 barg (400 psig), where the highest HC dew-point
temperature will be detected on the retrograde phase envelope.
The water dew-point (where fitted) is measured at full pipeline pressure, to determine
the highest water dew-point for the gas sample being analyzed.
The complete Condumax II Hydrocarbon Dew-Point Analyzer Sampling System can be
located close to the gas sample take-off point in a potentially explosive environment
- designated Class 1 Division 1 hazardous area.
The indoor version Sampling System gas handling components are assembled on
a stainless steel plate suitable for wall mounting within a temperature controlled
analyzer house.
The outdoor version Sampling System is housed within a stainless steel enclosure (304
or 316) for direct field installation next to the process line (with overall environmental
protection to IP66).
The Sampling System must be located in a constant temperature controlled environment
of at least +10°C (+18°F) above the highest envisaged dew-point temperature.
All sample gas wetted metallic parts are in AISI 316L stainless steel with Viton® soft
parts that comply with the NACE standard MR-01-75 (latest edition). Tube fittings are
twin ferrule compression type. All gas and cable entries are located in the base of the
enclosure.
The sample flow gas handling components are as follows:
• Gas Inlet Isolation Valve (BV1):
Allows user to manually isolate the system from the process sample gas
supply line for maintenance or servicing.
• Coalescing & Membrane Filter (F1):
Provides system protection from contamination of liquid carry-over of
hydrocarbon / glycol mist particles using membrane filtration.
Michell Instruments
INTRODUCTION
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