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Analyser Sample Systems
Analyser Sample Systems require experienced design engineering in order
to achieve a representative, conditioned sample for analysis. Engineering design
requires careful selection of materials, temperature and pressure conditioning
along with correct process data. Don't forget, it is generally accepted that
analyser sample systems are the victims of the Pareto principle (i.e., 20% of a
system consumes 80% of the resources) since they are responsible for 80% of
analyser system problems. This Analyser Sample Systems page and our sponsor Haldatec
hopefully will assist in getting this very important design and component
selection correct.
|
Haldatec |
Since 1990 Haldatec have been providing innovative products, systems and services to the Oil, Gas and related industries in Australia, Pakistan, Singapore, Papua Nugini, India, Malaysia, Italy, Thailand and New Zealand. Their main focus initially was in Oil and Gas Sampling, since then there has been a broader involvement into areas such as Gas Control Valves, Gas Tank Blanketing, Instrument gas skids, Pipeline Insertion Devices, gas filtration, instrument manifolds, leak detection and Odorant Injection systems. The Haldatec product line includes;
Have
a question on or need to purchase quality Sample Systems or their Components? Our
Sponsors Haldatec are Experts in this area!
Contact them here.
Practical
Considerations of Gas Sampling, Gas Sampling Systems and Standards - David
J Fish - The need to be able to take a representative sample of a
hydrocarbon product is necessary to ensure proper accounting for transactions
and efficient product processing. The various sampling methods that are
available and the options and limitations of these methods are investigated; the
most appropriate equipment to use; the reasons for its use and correct
installation of the equipment are also addressed.
Spot
and Composite Sampling for BTU Analysis - Determination and Natural Gas
Physical Properties - David J. Fish - The amount of hydrocarbon product that is
transported between producer, processor, distributor and user is significant. To
be able to verify the exact composition of the product is important from an
economic and product treatment standpoint. A small percentage savings made by
correctly determining composition will quickly recoup the investment made in the
purchase of a system designed to obtain an optimum sample. In addition, if the
best sampling procedures are followed, the potential for disputes between
supplier and customer will be greatly reduced. The importance of properly
determining hydrocarbon gas composition benefits all parties involved and will
achieve greater significance as this resource becomes more expensive and plays a
larger role in our energy needs worldwide.
Eliminating
Guesswork – Predicting Gas Temperatures for Analysers - Industry
now has available prediction techniques for calculating the temperature of
pipeline gas that is being presented to on-line analysers. Thus the risk has
been taken out of having a liquid laden sample or a non representative sample,
that can damage analysers or not make the analysis meaningful. Proprietary
programmes have been developed specifically for use with Welker insertion
regulators and Pressure Tech heated regulators.
Instrument
Filters
- These filters are used
extensively for removing contaminates that include dust, aerosols and water from
the gas before it is used for such duties as gas supply to pneumatic
instruments, valve actuators, and analysers.
Pressure
Regulators for Analyser Applications - Pressure
regulators are self contained devices that are often defined by their
application. Hence similar regulators are described as Instrument or Analyser or
High/Low Pressure. Whether
the regulator is a liquid or gas regulator they all work in the same way.
Porting may be different. Sizing is of course different with flow being
constrained by the physical size of the regulator and it's flow configuration.
Self
Contained Pressure Regulator - Sizing - This technical paper gives a
technical introduction on self contained pressure regulators, capacity sizing,
turndown and relief sizing.
Typical Crude Oil Sampling System - This technical diagram shows a
typical crude oil sampling system.
Analyzer
Liquid Shutoff and Eliminator Membrane Filter - The Liquid Eliminator
is designed to protect analyzers from damage and
contamination by removing liquids and particulates
in gas samples. The gas sample enters the housing
and flows through the membrane, effectively
eliminating any free liquids from entering the
analyzer columns.
Flow
Conditioner - This flow conditioner is designed to protect analytical
instruments from liquids. Welker has taken two of it’s products and combined
them into one great product. The “Guardian” is quick and easy to install.
The “Guardian” is equipped with a shut-off ball that floats on the free
liquid and moves up to shut off the flow of liquid slugs that would flood the
analyzer. This design is to help protect analyzers from damage and contamination
by removing liquids and particulates while sampling.
Hot
Loop Sample Probe Conditioning System specially designed for Moisture Analysers
on Triethylene Glycol Dehydration Units - This unit is designed to
gather a representative sample to remove free liquids and deliver a low pressure
gas sample to a analyser.
6.12
Shale
Gas Sampler Applications - This presentation from Welker Engineering
gives an overview of Sampling Systems for the hot topic of Shale Gas
Development.
The
Basics of Analyzer Sample Systems
Written by Ian Verhappen
Included in this article are two
spreadsheets for calculating pressure drops:
Pressure
drops in a liquid line
Pressure drops in a vapour line
Process
Analyser Sample Conditioning System Technology Book
This book provides both novice and
experienced technologist with the technical background necessary to choose
sample conditioning system components that will allow the process analyzer
system to function reliably with minimal maintenance.
The conditioned process sample presented to the process analyzer should be
of similar quality to the calibration material used to zero and span the
analyzer. Filling a long-standing void in the process field, this book
addresses the system concept of Process Analyzer Sample-Conditioning
Technology in light of the critical importance of delivering a
representative sample of the process stream to the process analyzer.
Offering detailed descriptions of the equipment necessary to prepare
process samples, and listings of two or more vendors (when available) for
equipment reviewed, Process Analyzer Sample-Conditioning System Technology
discusses:
• The importance of a "truly representative sample"
• Sample probes, transfer lines, coolers, and pumps
• Sample transfer flow calculations for sizing of lines and system
components
• Particulate filters, gas-liquid and liquid-liquid separation devices
• Sample pressure measurement and control
• Enclosures and walk-in shelters, their electrical hazard ratings and
climate control systems
The
following are from our sponsor Haldatec
Light
Liquid Hydrocarbon Sampling - In the sampling of light liquid
hydrocarbons, the liquid state of the sample must be maintained at all times. To
accomplish this, the equipment and operating features detailed in this technical
list should be employed.
Gas
Sampling Applications- Gas Sampling
usually takes three forms, spot, continuous or representative, this technical
bulletin gives information on this.
Liquid
Sampling Applications - Sampling
liquids usually takes two forms, spot or representative. Spot
samples are taken at one time at one point, normally via a pitot tube inserted
in the process or pipeline. The sample is collected in a sample cylinder and
taken to a laboratory for analysis.
This form of sampling will only give a sample that is representative at
one point in time only. Alternatively,
Representative samples of light oil or condensate are collected using a by-pass
sampler mounted adjacent to the pipe or mounted directly on the pipe. Grab
samples are then collected in a sample cylinder over a period, for later
analysis in a laboratory. For
heavier oils such as Crude Oil or oils with contaminates in them, the by-pass
method is not favoured, a direct mounted insertion type sampler is used. This
type of sampler will take a representative sample from the centre of the pipe.
The oil should first be thoroughly mixed using an upstream static mixer to
ensure the best homogeneous sample is taken.
Collection
and Safe Transportation of Hydrocarbon Samples - David A Dobbs and David
J Fish - This paper discusses the various types of collection methods and
collection devices as well as the importance of proper collection cylinder
construction, benefits of constant pressure sampling together with comparison of
results from various sampling methods. Transporting samples for analysis
remote from the collection point is often necessary and presents problems in
selecting the appropriate container and mode of transport. Safe transportation
is critical and subject to regulation, as well the integrity of the sample needs
to be maintained. The various regulations and transport options are also
detailed.
Other links
Ever wondered where to get
auto-samplers? Try these companies via a search on Google
Bristol Equipment Company
Clif Mock Company
Jiskoot Incorporated
Buehler
Texas Sampling
Sirco
Thermo Ramsey
SA-77
What International Standards Govern Sampling System Selection, Design, Installation and Operation? - There are four major standards that govern 'Sampling liquid hydrocarbons in pipelines'. They are ISO 3171, IP 6.2, API 8.2 and ASTM D4177 - from Jiskoot
Grab
Sampling Systems: Maintaining Quality and Safety - The need for representative samples plays a critical
role in ensuring product verification. Yet sampling
directly from the process often includes the risks of exposure to the
operator as well as contamination and pollution to
the environment. The DOPAK® sampling method reduces such risks
with its patented design and simple method of operation. Thanks to Dopak
1.13
How
to Manage Vaporization in an Analytical System
- D Nordstrom and T Waters -
When done properly, this process ensures that all compounds vaporize at the same
time, preserving the sample’s composition - from Swagelok and Hydrocarbon
Processing.
1.13
Verify
Fluid Flow to Your Analyzer and Keep Your Plant Running - Sam Kresch - No
matter how sophisticated a fluid analyzer system may be, it will be ineffective
if a sample flow fails to reach the analyzer sensor or if the sample is
contaminated or stale. The most advanced systems in the world cannot provide
accurate results without a valid fluid sample. Gas chromatographs (GCs), mass
spectrometers, optical spectrometers and photometers are a few examples of
analyzer technologies applied in process and plant systems that need sample flow
assurance. It is an accepted industry best practice that sampling systems have
some type of flow monitor to assure valid samples and analysis - from Fluid
Components.
1.13
A
New Era of Liquid Chromatography: Improving HPLC Throughput with Automation and
Real Time Diagnostics - Today's drug discovery labs are charged with moving
thousands of samples through HPLC and MS screening processes. If your lab is
operating 24x7 to keep up with the throughput demand, every second counts. To
achieve high throughput, not only must the run time of a single analysis be
shortened, but the total cycle time of the injection sequence and run time needs
to be optimized. Solvent management automation and real time diagnostics allow
you to increase sample throughput and maximize system uptime while meeting the
need to produce reliable results and identify leads. This automation and
diagnostics can be achieved by installing an in-line real time flow measurement
device in the solvent management system - from Brooks Instrument.
The Following Technical Articles are from Jiskoot
What
are the most important steps to consider when Designing or Specifying a Sampling
System? - In a typical sampling application, the volume
analysed is between 1 and 300 billionth of the total batch. When the custody
transfer and batch quality is determined by such a small sample it is vital that
it is representative of the fluids being sampled. The standards defines a number
of steps that need following to ensure successful sampling - from Jiskoot
Why
do the Standards Demand that Pipeline Contents must be Homogenous? -
A sample is taken from a single point in the pipeline. Water and oil do not mix
and therefore it is vital that the point of sampling is representative of a
cross section of the pipeline. This can only be achieved by mixing. Natural
mixing can be provided by valves, elbows and natural turbulence generated by the
flow- from Jiskoot
How
can you decide which type of Mixing System is Best Suited to your Application?
- Selection of the correct mixer as with any process conditioning
depends greatly on the application. There are two main types of pipeline
mixing systems available
Sampling
Systems - The Options - What is the accuracy of different sampling systems
and which is best for your application? There are two main types of sampling
systems, probe based systems and bypass loop sampling systems.
What
is a Representative Sample? - How do you know if I have a representative
sampler?
Sample
Receivers - Which type of sample receivers should you use? Once a
representative sample has been extracted from the pipeline, it must remain
representative in the sample receiver and when analysed in the laboratory.
The standards recommend the use of either fixed or variable volume depending on
the properties of the fluids being sampled.
Sampler
Control Systems - What type of control system is recommended by the
standards? The primary function of the control system is to operate the sampling
device in a time or flow proportional manner. This normally requires that the
controller have a real-time operating system. The system should allow the
operator to enter the batch size and should determine the necessary sampling
rate to achieve the correct volume of sample.
Sampler
Performance Factors - How can you guarantee that a sampling system performs
as specified? The performance of a sampling system is normally monitored by
measuring the accumulated sample volume and comparing it with the expected
sample volume. The variance allowed across the whole batch is +/-10%.
How
can you Sample the Line-fill between the Sampler and Custody Transfer Point?
- The volume left in a pipeline after a batch between the sampling system and
the point of custody transfer (maybe a metering system or ship's manifold)
can be substantial. In the event that this is large it may be necessary to
sample the line-fill to measure the quality, as in the case of ship unloading
operations this is often when the worst part of the cargo is discharged.
Sampling
System Proving - How can you guarantee, prove and certify that a sampling
system complies with the standards? A sampling system needs proving once
installed. Only then can you certify that a system performs as specified. The
only way to prove beyond doubt that an installed sampling system complies with
the standards is to prove the system by water injection. The procedure is
defined in the standards.
Crude
Oil Sampling - Crude oil sampling for custody transfer, fiscal,
allocation or quality measurement purposes should be performed in accordance
with sampling standards of ISO 3171, ASTM D 4177, API 8.2 and IP 6.2.
These standards dictate a number of key design issues and steps that must be
considered to ensure a system fully complies with the standards.
The
“Art” of Crude Oil Sampling - Mark Jiskoot - Crude oil is sampled to
establish the composition quality, density and water content. The quality is
normally known when the oil is purchased, as is the approximate density, for a
cargo there is "expected" water content but receipt terminals can
often be surprised by a water content that is far higher than the "bill of
lading" as stated by the loading port. Depending on how the purchase
contracts are written, discovery of more water may give rise to a claim first on
the shipper and then on the supplier.
Crude
Oil Sampling Customer Satisfaction - Mark A. Jiskoot - Loss
control specialists wish to be sure of both the quantity and quality of the oil
received on board ship and at point of discharge (receipt port). Confidence in
the measurement accuracy reduces risk and improves the demand price of the
batch. The quality measurement accuracy is a function of all the steps involved
in sampling, failure to maintain the representive sample at any point i.e. from
pipeline to analysis invalidates the sample by introducing random errors.
Crude
Oil and Condensate Sampling, Water in Oil and Density Measurement - What is
the uncertainty of your quality measurement system? - Mark A. Jiskoot - The
various standards applicable to sampling, density and on-line water content
measurement have been developed and updated over many years but the most
significant advances have happened over the last 20 years. While sampling
systems have always been a feature of the metering process, many metering
systems installed have been modified to incorporate density compensation (to
yield total mass) water-in-oil monitors (OWD or On-line Water in petroleum
Devices) or both. Integrated systems are now titled QMS or “Quality
Measurement Systems”. Unfortunately, and to their cost (at least that of their
company), many loss controllers pay the price for poor measurement by way of
claims so there is a strong commercial reason to get measurement “right”.
Crude
Oil Quality Measurement -Loss Reduction Through Technology - Jon Moreau
& Mark Jiskoot - Quality measurement system design and laboratory equipment,
handling techniques and analysis methods have improved significantly over the
last 20 years. Simultaneously, suppliers and users have worked together to
develop/validate and improve measurement performance. One of the most
significant steps in achieving this has been the collation and evaluation of
water injection "proving" tests. This large (often independently
validated) and rapidly growing data set enables a comparative evaluation of the
performance of custody transfer sampling/on-line measurement systems. Proving
the accuracy of an installed quality-measurement system is a challenge, even
more so than proving a metering system. It requires adjustment of a physical
property (in this case water content) and validating that the system accurately
measures that change. However, unless an installed system has been proved and
certified as compliant with the standards, its use to arbitrate claims or for
custody transfer becomes questionable.
IP
Petroleum Measurement - Mark A. Jiskoot The interest in sampling accurately
has led to a plethora of studies and the generation of the standards we now use.
Much of the original content was based upon what was then known, bolstered with,
one hopes, educated guesses.The testing of systems designed within
practical/cost limitations has allowed us to accept or reject certain
conceptions and better learn the envelope in which we should operate. This paper
outlines some of the problems to be addressed and some of the discoveries made.
Increased
Profitability through Effective Measurement - Mark A. Jiskoot & Jon
Moreau - The measurement of a Crude Oil shipment at an import terminal
forms the basic measure of profit performance.Accurate techniques for
measurement of flow are well documented and understood. The factor that is often
overlooked is the accurate measurement of actual water, density and composition.
Crude oil and water do not mix and therefore it is fundamental that any
measurement of water content not only considers carefully how a sample is
extracted but also how it is handled and tested. Typical errors in poor sampling
techniques result in payment of oil prices both to transport and to process
water. While the percentage errors between sampling methodologies may appear
insignificant (of the order of 0.05- 0.15%) the volumes of crude traded make the
losses significant and can easily justify the installation of an accurate
sampling system that both the seller and purchaser can be confident in. The
International standards of ISO 3171 clearly define standards which meet the
requirement of accurate sampling of liquid hydrocarbons in pipelines.
Natural
Gas Sampling - An Overview - Robert J. J. Jiskoot - Once a by-product of oil
production discarded and flared off, Natural Gas has become an increasingly
valuable energy source. The ability to verify the composition of the hydrocarbon
gas is critical to the determination of its commercial value, be this in
gathering, transportation or loading systems. Accurate and reliable sampling
allows both buyer and seller to be confident of a fair transaction. The
investment associated with the purchase and installation of a composite gas
sampling system, correctly designed to provide a representative sample, will be
quickly recouped. This paper attempts to outline the correct procedures and
considerations that are necessary to obtain a representative gas sample.
Jet
Mixing - A New Approach to Pipeline Conditioning - M.A. Jiskoot - Accurate
sampling from a flowing pipeline requires that the point from which the sample
is drawn is representative of the average (quality) of the whole cross section.
Fuel
Oil (Bunker) Sampling Break the link between Politics and Quality - Mark A.
Jiskoot - The objective of sampling is to determine to the highest degree of
accuracy possible, the properties of the fluid sampled.This proves beneficial to
all parties as it can, if properly executed, ensure fair transactions. As the
value of product increases or, as in the case of fuel oil, the potential for
claims increase, it is necessary to assure all parties of the properties of the
transaction both at the time of sale and in case of dispute later. In reading
bunker related press it also becomes obvious that aside of the issue of a
"fair deal" assurance of quality can have significant impact on the
prevention of engine failure and the consequent disasters and claims than ensue.
PSA and DNV have both made serious attempts to assure certain sampling
procedures but it is the belief of the author that these are not yet enough.
This paper is to outline the basis on which an accurate sample should be taken,
sampling techniques which if used will serve to both improve the overall quality
of the trade and to determine unintended quality problems which need resolution.
How
Accurate is your Receiving Metering System? - Mark A. Jiskoot - Errors in
terminal receipts due to poor sampling designs and procedures can result in huge
losses. When receiving crude shipments via tanker, there is some doubt on the
quantity of product unloaded. Many errors can be attributed to discrepancies in
sampling and metering results. Oil quality measurement methods are under
continual review. How much water are you actually purchasing in the latest
receipt? An answer is determined by what methods are used to get product
densities and the accuracy of laboratory analysis. Should physical sampling
methods be replaced with online devices? These are just a few of the issues that
refiners must consider as they try to improve the operation of their terminal
metering systems.
Wet
Gas Metering / Sampling - New Method to Determine the Liquid Content of a
Wet Gas Stream and Provide a Sample of the Liquid Phase for Compositional
Analysis.- Mark A. Jiskoot and Ken Payne - There is currently no other method
available that is capable of accurate measurement of the liquid mass of a wet
gas stream. Jiskoot has, in conjunction with AMEC, developed a wet gas sampling
methodology that can determine the liquid/gas mass ratio as well as providing a
compositional sample to allow laboratory determination of the chemical
composition of condensates, methanol and water.
Improving
Customers Profits through Innovation and Technology - Jon Moreau - With the
price of crude oil remaining high, many oil companies and refiners are focusing
on how new technology can reduce costly measurement errors. The importance of
quality as a part of the overall quantity measurement process is being put in
the spotlight by rising hydrocarbon prices. 100,000 barrels of crude oil does
not have the same value if it contains 1.5% water as it does if it contains 0.5%
and poor 'quality' measurement that masks these figures can have a significant
impact on profitability.
Sampling
Technical Papers - Some super technical information on
sampling from Jiskoot International.
Advances
in Natural Gas Sampling Technology - Donald
Mayeaux - The monetary value of natural gas is based on its energy content
and volume. The energy content and physical constants
utilized in determining its volume are computed from
analysis. Therefore correct assessment of the value of
natural gas is dependent to a large extent on overall analytical
accuracy. The largest source of
analytical error in natural gas is distortion
of the composition during sampling. Sampling clean,
dry natural gas, which is well above its Hydrocarbon
Dew Point (HCDP) temperature is a relatively
simple task. However, sampling natural gas that
is at, near, or below its HCDP temperature is challenging.
For these reasons, much attention is being focused
on proper methods for sampling natural gas which
have a high HCDP temperature. This
presentation will address problems associated with sampling
natural gas which is at, near, or below its HCDP temperature.
Various approaches for solving these problems
will also be discussed - from A+ Corporation
and intellisitesuite.com
Spot
Sampling of Natural Gas - Jerry Bernos - In 1978 the United States Congress
passed the Natural Gas Policy Act. This legislation required that natural gas be
priced according to its energy content rather than by volume alone. At the same
time, the economics of the natural gas industry caused natural gas prices to
soar. These two factors resulted in a vast increase in the demand for accurate
analyses of natural gas systems. Since it was not economically feasible to place
analytical instruments at each and every location requiring BTU determinations,
a corresponding increase occurred in the need to obtain "spot" samples
of these systems. This paper is intended to present the problems that arise in
"spot" sampling and to introduce the industry accepted methods, which
can overcome these problems.
Techniques
of Gas Spot Sampling - George L. Bell, Sr - A natural gas sample may
collected as a spot, composite, or as a continuous sample connected to a
chromatograph. The most important things in taking a sample are where and how
the sample is taken - From PGI International and intellisitesuite.com
How
to use a Regulator to Reduce Time Delay in an Analytical System -
Doug Nordstrom and Mike Adkins - Process measurements are instantaneous
but analyser responses never are. From the tap to the analyser, there is
always a time delay. Unfortunately, this delay is often underestimated or
misunderstood - from www.chemicalprocessing.com.
Designing
On-line Chromatograph systems for Liquid Fractionation Facilities
- Murray Fraser - Liquid
fractionation plants can optimize their operations by installing on-line
gas chromatograph systems that have been properly
designed to provide reliable, fast, accurate
results. One of the most important, but overlooked,
facets of designing an on-line analytical system for
gas processing facilities is the sample conditioning system (SCS). The
sample delivered to the Gas Chromatograph (GC) must truly
represent the process media if the measurement is to
be accurate — or even meaningful. Samples may be
transported to the GC in either gas or liquid phase, but they will
ultimately be analysed in the gas phase only.
Selection of sample location and careful attention to
sample phase (liquid or gas ) is required to ensure optimum system
performance. Discussed in this paper are: typical
process conditions, GC location, sample transport
systems, and details of both vapour- and liquid-phase sample conditioning
- from Daniel Measurement and Control.
Breathe
Easy - Darrell Leetham -For many organisations
today, one aspect of the manufacturing process that needs to be monitored
and controlled, for both efficiency and environmental benefit, is gaseous
emissions - Plants are constantly looking for means to increase production
and decrease costs. Increases in production are generally associated with
an increase in fuel consumed and, in turn, a subsequent increase in
emissions generated. In addition, regulatory entities are increasingly
implementing standards and setting requirements for monitoring and
reporting data on plant emissions. In order to improve efficiency
throughout a manufacturing process and at the same time meet the needs of
sustainable development goals, industry is finding an increased need for
robust, reliable and accurate gas analysis methods. To meet the needs of
this demand, different technologies for gaseous emissions sampling and
analysis have been developed over the years. One particular technique is
to extract a gas sample and dilute that sample prior to analysis. This
article explains some advantages of the dilution extractive method. From
Thermo Fisher Scientific and processonline.com.au.
Center
for Process Analytical Chemistry
- CPAC, established at the University of Washington
in 1984, is a consortium of Industrial, National Laboratory and Government
Agency Sponsors addressing multidisciplinary challenges in Process
Analytical Technology (PAT) and Process Control through fundamental and
directed academic research. The present CPAC program
can be summarized by two main components;
(1) new measurement approaches including the miniaturisation of traditional instrumentation and the development of new
sensors and non-traditional instruments.
(2) mechanisms for interaction, collaboration, and communication of center
activities, research programs, and information related to process
analytical technology (PAT)
among sponsors, other universities and academic departments, government
agencies, and the general measurement and control community. CPAC
has an established track record in fostering academic/industrial/national
laboratory interactions, which aim at bridging the gap between basic
research and full-scale process/product development
Techniques
of Composite Sampling - Kris
Kimmel - Since a gas sampling system can be referred to as a “cash register”
it is very important that the correct sampling method
be selected and the appropriate industry standard be
followed. Methods reviewed by this paper will include spot
sampling, composite sampling, and on-line chromatography.
In addition, Gas Processors Association (GPA)
2166-86 and American Petroleum Institute (API) 14.1
will be described - from YZ Systems, Inc
and intellisitesuite.com
The
Integrity And Reliability Of On Line Process Analyzers is Crucially Related To
The Design Of The Supporting Sample Handling System - Ronald A. Downie -
Although a considerable amount of attention is normally given to the selection
of the most suitable type of analyzer to perform the desired analytical task, a
similar amount of attention is all too often not extended to the sample
conditioning system. This may be due to a lack of understanding of the
importance of this part of the complete system. A well-designed, properly
applied measuring system can do no better than give a correct analysis of the
sample being supplied to it. If the sample is not representative of the process,
there is nothing an analyzer can do to correct the situation, and the analytical
data can not be used for control purposes. The results of poorly designed sample
conditioning vary from the analyzer not operating at all to an analyzer
operating only with extremely high maintenance requirements and/or giving
erroneous or poor data - from Teledyne Analytical Instruments.
CT76
Modular Substrate and Component System - This bulletin from ICEweb sponsor Circor
describes why this is "State of the Art" for modular
systems.
Modular
Substrate Sampling System (µMSł™)
- from ICEweb sponsor Circor
Rethink
Sample System Automation
- NeSSI provides new tools to tackle the challenges and improve
performance - By Robert N. Dubois, consulting analytical specialist - Thanks to
chemicalprocessing.com
NeSSI™
Generation II Specification - A Conceptual and Functional Specification Describing
the Use of Miniature, Modular Electrical Components for adaptation to the
ANSI/ISA SP76 Substrate in Electrically Hazardous Environments - This functional and conceptual specification is based on
the use of the miniaturized, modular analytical systems
designed to the ANSI/ISA SP76.00.02-2002 standard substrate. This 2nd
generation specification deals chiefly with
integrating electrical components such as sensors and actuators
(collectively referred to as transducers) onto the
substrate in a manner suitable for use in electrically hazardous areas
commonly found in petrochemical, refining and
chemical facilities - Thanks to CPAC
6.12
NeSSI Keeps Chipping Away
- The Plucky Sampling Sensor Initiative and Its Advocates
Keep On Encouraging Users to Gain the Many Benefits That Its Standardized
Hardware, Communications and Microanalytic Specifications Can Bring to
Process Analytical Systems -Launched in 2000 by the Center
for Process Analytical Chemistry (www.CPAC.Washington.edu) at the
University of Washington, Seattle, NeSSI's Generation I specification for
its modular, compact, mechanical substrate and other hardware evolved from
the ISA SP 76 standard. Next,
CPAC and NeSSI's supporters released its Generation II specification for
automation and communications in 2004 and more recently, its
Generation III specification for microanalytical devices, which is NeSSI's
ultimate goal - from Control Global.
The Following articles are from www.chemicalprocessing.com
NeSSI’s
Success should be a Lock - Mark Rosenzweig - The New
Sampling/Sensor Initiative or NeSSI that replaces tubing, fittings and other
hardware in a sampling system with miniature modular components makes sense.
Enhancements now in the works should assure its success.
Intrinsically
Safe NeSSI Nears - An emerging bus standard promises to spur
application in hazardous environments - Rick Ales - The New
Sampling/Sensor Initiative (NeSSI) has provided the basis for modular
miniaturized process sampling systems that offer ease of assembly and
flexibility while cutting cost of ownership. Not surprisingly, plant acceptance
of such NeSSI systems is growing. A group of analyzer specialists now is working
to enable NeSSI to be used in hazardous environments. They envision an
analytical system with smart transducers that would be capable of being field
mounted at the sample point in a potentially explosive atmosphere and would be
easily integrated into the analyzer control system.
Smaller,
Smarter Systems Streamline Sampling - Mike Spear - An
emerging miniaturized, modular approach for sampling systems provides
substantial savings in both capital and operating costs - Faced with ever
increasing competition on price for their products, chemical companies are
constantly searching for ways to cut costs across their operations. This, in
turn, puts persistent pressure on engineers to reduce both capital and operating
expenditures — without compromising their plants’ reliability and
performance in any way. Easier said than done, perhaps, but this is precisely
what a new approach to the task of delivering process samples to analyzers
actually delivers, claim its proponents.
Since coming into being some five years ago, the New Sampling/Sensor Initiative
(NeSSI) has become the driving force behind the move to modularize and
miniaturize process sampling systems. Now operating under the sponsorship and
umbrella of the Center for Process Analytical Chemistry (CPAC) at the University
of Washington, Seattle, NeSSI first surfaced as an ad hoc group of people drawn
both from equipment manufacturers, keen to adopt the modular approach, and
operating companies prepared to put the vendors’ prototype products to the
test on their plants.
Streamline
Your Sampling System
- Selecting the right stream selection assembly can improve performance - John
Wawrowski, Doug Nordstrom and Joel Feldman.
Constant
Pressure Sample Cylinders with Additional Special Purpose Standard Cylinders
- Constant Pressure Cylinders are being increasingly used to address the
problem of fugitive emissions in spot sampling situations and have been used for
many years in continuous sampling applications. They have minimal dead space,
eliminating or minimising the need to purge, are safe to transport, easily
cleaned and maintained. There are a variety of construction options and
accessories available from our sponsor Haldatec.
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