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Data is not real-time

Typically it takes one month to collect sample before it is sent

to the laboratory for analysis. Although the analysis probably

only takes a week, it could still be another three weeks before

the technician is back at the site to collect the next sample

bottle. By the time the gas quality data is entered into the flow

computer it could be anywhere from 1-2 months old.

Data is not accurate

Although the lab analysis is very accurate it is only as good

as the sample handling practices that were used to obtain the

sample. IF the sample bottle is not properly purged or clean

when it was installed then the analysis data will be corrupted.

The error gets magnified when applied across a whole month

of gas production.

Data is difficult to obtain and not cost effective

Shipping requirements and DOT regulations make it

increasingly difficult to ship samples to the central laboratory.

These problems with composite sampler had to be tolerated

because the cost of a GC was too much to put on these lower

volume stations, UNTIL NOW.

Solution: NGC8106

ABB is pleased to introduce the NGC8106. Based upon the industry leading NGC platform,

the NGC8106 is a perfect replacement for composite samplers. The user can now enjoy

real-time data instead of monthly averages, and shipping and sample collection errors have

been virtually eliminated. Add-in a multivariable transmitter and the NGC8106 becomes a

total energy meter. Or utilize the remote communications on the 8106 to transmit real gas

quality data to an existing flow computer.

Composite samplers

Natural gas is exchanged on the basis of how much energy it

contains. One must not only know the quantity of gas going

through a receipt point, but they must also know the quality of

gas going through the receipt point.

Their most common primary metering device to measure gas

quantity is an orifice plate meter with a flow computer. The

orifice plate causes a pressure drop in the meter tube. The

flow computer senses the pressure drop and calculates the

volume based upon standard equations. Orifice plate meters

are simple, low-cost and installed on a very large percentage of gas wells.

For gas quality, a gas chromatograph is required to provide a

gas composition from which the heating value is calculated.

However, most sites do not have enough gas volume to

justify purchasing a chromatograph. To alleviate this problem,

composite samplers were installed on measurement sites

where the flow was too low to justify a dedicated GC.

A composite sampler is a device containing a sample bottle.

On a periodic basis, either time or volume based, the sampler

will put an aliquot of gas in the sample bottle. The sample

bottles are collected either monthly or quarterly depending

upon the sales contract, and sent to a lab for analysis.

Problems with composite samplers

Standard features

Modular design includes

– Modular software – application-based, plug-in software modules

– Manifold module (internal tubing now replaced manifold)

– Analysis section contains stream selection solenoids,

pressure regulation, 32-bit digital detector electronics, and a

single-train chromatograph in a single, replaceable module

– 32-bit digital, low power, controlling electronics. Using

Windows CE® (internal to GC unit)

– Microsoft® Windows® 2000 or XP-based, remote user

interface software

– Lithium battery-backed RAM

– Two remote serial digital communications ports; one local port

– Comprehensive diagnostics and wizards available to users

– Two-level security for user access control

– Audit-quality historical data; date and time stamped

– Operational alarms available with each analysis cycle

– Detectors – constant temperature, glass encapsulated

thermister beads for rugged service and long life. Will not

burn out on loss of carrier

– Valves have no moving metal parts

– Single stream – Manual Calibration

– On demand diagnostics

– Available standard sample conditioning system

– Front panel consisting of LED indicators for: Run, Hold,

Calibrate, Warning, Fault, Warm-up

– USB (host and client) and ethernet ports

– SD memory cards

– Optional Feed-through heater

– AGA3/AGA7 flow calculations

– API 21.2 compliant flow computer functionality

The NGC8106 performs on-site, real-time gas analysis and

heating value computation. The 8106 can be used as a total

energy meter with the addition of a multivariable transmitter!

The NGC8106 is a perfect replacement for automatic

samples. The user will enjoy real-time data instead of monthly

averages, and shipping and handling errors have been virtually

eliminated. The NGC8106 is based upon the industry leading

NGC8206 platform.

Innovations include

– Compact design

– Extreme serviceability

– Low installation costs

– Low utility requirements

– Low maintenance

– Unmatched performance

Simple, reliable, easy to service, low cost measurement.

The perfect choice to replace automatic samplers

Introduction

The NGC8106 is a field mounted GC capable of a C6+

natural gas analysis. By bringing real-time gas quality data

closer to the wellhead, the NGC8106 is the perfect choice to

replace automatic samplers. Not only will users enjoy real time

measurement to correct their flow calculations, users will no

longer have to deal with the cumbersome tasks of shipping

samples and the sample handling errors that can result.

Real time measurement and heating value computation

ABB flow computers, analyzers and sensors customarily

set defacto standards for natural gas custody transfer

measurement. As an extension of the NGC8206, the

NGC8106 introduces a new paradigm by allowing real-time

measurement at lower volume stations where it was previously

cost-prohibitive to put a GC.

Historical data

The NGC8209 is designed to retain historical data. This data

can be used for custody transfer needs, verify transmitter

operation over time, and provide a limited data backup for

communication link reliability. In addition, various CSV file

outputs are available to download the analysis data into

spreadsheet based company specific data sheets, and

outputs to 3rd party gas accounting packages.

The default¹ memory configuration provides the most recent

480 analysis cycles containing:

– Normalized components

– Un-normalized components

– Ideal Btu/CV

– Real Btu (wet and dry) / CV (superior and inferior)

– Relative density (specific gravity)

– Density

– GPM

– Wobbe index

– Alarms

Stream averages for the (default¹) 840 last hours, 35 last

days and the most recent last month analyses. Operational

Parameters for the (default¹) last 480 cycles (Diagnostics Report):

– Selected peak times

– Selected peak areas

– Ideal Btu/CV

– Carrier regulator pressure

– Oven temperature

– Ambient temperature

– Sample pressure

– Detector noise values

– Detector balance values

Audit logs (Default¹)

– Last 480 alarms

– Last 480 events

Data retained by the NGC8209 can be collected via a remote

communication link or by the laptop PC local operator

interface PCCU 32.

Description

The truck is moved as close to the sample point as is practical.

A flexible sample line is then uncoiled and attached to the probe

in the flowing natural gas pipeline. If the dew point of the gas or

the weather demands it, this flexible tubing must be heated. A

sample of the gas is extracted from the probe in the line, purged

through the flexible line and then transported to the analyzer.

There it is processed for particle removal and phase integrity,

injected onto the chromatographic columns where component

separation occurs. These components are then quantified by

peak integration and concentration is calculated. The other data

of interest is then calculated from these concentrations.

The Portable NGC8209 analyzes each sample utilizing

established chromatographic techniques. The resulting

information consists of mole percent values for the following:

– Air (Contains N2, Ar, CO and O2 but not CO2), C1, CO2, C2,

C3, IC4, NC4, NeoC5, IC5, NC5, C6’s, C7’s, C8’s, C9+

The NGC8209 measures a C9+ (back flushed) peak. Users may

input the results of a comprehensive lab analysis that reflects

the split or ratio of C9 through C12 components. This ratio can

be used in subsequent analyses and energy calculations.

Calculated values include

– Relative density (specific gravity)

– Btu/CV (heating) value

– GPM (gallons of liquid per thousand cubic feet)

– Wobbe index

Standard features

Modular design includes

– Portable GC interface allows user analysis customization

– Modular software – application based plug in software

modules

– Manifold module (internal tubing now replaced by manifold)

– Analysis sections contain stream selection solenoids,

temperature and pressure regulation, 32 bit digital detector

electronics, replaceable column / valve modules and a low

power 32 bit digital controller, using Windows CE® (internal

to GC unit)

– Microsoft® Windows® based man-machine interface

software (PCCU)

– USB MMI port connectivity

– Ethernet connectivity

– Lithium battery-backed RAM

– Two remote serial digital communications ports; one local port

– Comprehensive diagnostics and wizards available to users

– Audit-quality historical data; date and time stamped

– Operational fault/warn alarms available

– Detectors – constant temperature, glass encapsulated

thermister beads for rugged service and long life; will not

burn out on loss of carrier

– 10 port valves have no moving metal parts in each

analysis unit

– Low utility usage – low-power, low-carrier, no instrument air

required

– On demand or scheduled automatic calibration and

diagnostics

• Calculation packages (eg, Hydrocarbon Dew

point via SRK and Peng-Robinson, including: 4

pressures and the Cricondentherm)

• Integral gas flow tube calculations (e.g. Orifice or

turbine meter calculations)

• SD memory cards for raw chromatogram storage

• Feed-Through heater for colder operations or

high dew point gas sampling

Introduction

The Portable NGC8209 is a natural gas chromatograph

designed for installation in a vehicle, allowing it to be used

for real-time analysis on any site that can be driven to.

The NGC is easily powered, either from the vehicle’s 12Vdc

system or from a 110VAC inverter. Its low power operation

means you can maintain continuous power on the unit, thus

keeping it at operating temperature and assuring it is ready

for immediate use on site.

From the spot analysis the following are calculated:

– Relative density

– Heating value

– VOS (velocity of sound)

– GPM (gallons of liquid per thousand cubic feet)

– Wobbe index

This data can be used for flow computers, RTU’s, gas

accounting systems, and SCADA systems for the Energy,

AGA3, 7, 8 and 10 calculations t the meter site. This data

output can be a CSV file format so that analysis data systems

can easily incorporate the information. The number of runs

and the number of averages can be selected. The averaged

output can be formatted to be accepted by a 3rd party gas

accounting software system, allowing automatic downloads

of the analysis data. Analysis done on site is valuable because:

– Transportation of DOT regulated gas cylinders is avoided

– Time and cost of subsequent laboratory analysis

– Problems with sample handling

– Economic solution for gas quality measurement when the

gas volumes are too low to justify on-line chromatography

• Auto-start cycle automatically after power failure:

◊ Stabilizes oven temperature

◊ Confirms modules’ functions

◊ Checks for operational alarms

◊ Returns to pipeline streams

• Operational alarms available with each analysis cycle.

• Detectors – constant temperature, glass

encapsulated thermister beads for rugged

service and long life. Will not burn out on loss of

carrier.

• 10 port valves have no moving metal parts in

each analysis unit

• Low utility usage – low-power, low-carrier, no

instrument air required 

• On demand or scheduled automatic calibration

and diagnostics

• Continuous monitoring for alarms

STANDARD OPTIONS

• H2S measurement from 0.02% and higher

• Sample Conditioning Modules

• On board digital 1/4 VGA display with multiple

screen access

• Calculation packages (eg, Hydrocarbon Dew

point via SRK and Peng-Robinson, including: 4

pressures and the Cricondentherm)

• Integral gas flow tube calculations (e.g. Orifice or

turbine meter calculations)

• SD memory cards for raw chromatogram storage

• Feed-Through heater for colder operations or

high dew point gas sampling