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Industrial Growth Partners Acquires Process Insights

Industrial Growth Partners Acquires Process Insights


San Francisco, CA – Industrial Growth Partners (“IGP”), in partnership with management, has acquired Process Insights, Inc. (“Process Insights” or the “Company”) from Union Park Capital.

With global operations across North America, Europe and Asia, Process Insights designs and manufactures analytical instrumentation used to provide compositional analysis and measure contaminants within gases and liquids in demanding and high cost-of-failure applications. The Company provides a broad portfolio of analytical technologies for in-line, on-line and at-line testing, including optical spectroscopy, mass spectroscopy, chilled mirror / hygrometry and electrochemical technologies. Process Insights’ products provide real-time, tight-tolerance speciation and analysis, enabling its customers to enhance process efficiency, ensure safety and maintain environmental and regulatory compliance. Process Insights’ products serve a broad range of end markets including semiconductor, renewable / alternative energy, life sciences, chemical, environmental monitoring, agriculture, food & beverage, general industrial, labs & research, and water & wastewater.

“We are excited to partner with IGP and leverage their resources for strategic and operational support as we embark on our next phase of growth,” commented Monte Hammouri, CEO of Process Insights. “IGP’s decades of industrial sector expertise, and specifically its track record with test & measurement businesses, stood out to the full management team as a true differentiator. We are confident that with IGP’s support, we will continue to grow Process Insights into a global leader of process instrumentation.”

Acquisition Details. On July 18, 2023, Industrial Growth Partners VI, L.P., in partnership with management and certain other co-investors, acquired Process Insights, marking the fourth platform investment for IGP’s sixth fund. The transaction creates a platform for Process Insights to accelerate its growth by aggressively pursuing its strategic initiatives, including pursuing additional add-on acquisitions. The acquisition of Process Insights is an ideal fit with IGP’s strategy of investing in niche industrial companies with leading market positions, significant growth opportunities and outstanding management teams. To learn more about Process Insights, please visit www.process-insights.com.

William Blair & Company, LLC served as the exclusive financial advisor to IGP in connection with the transaction.

Industrial Growth Partners, founded in 1997, is a San Francisco-based specialist private investment partnership investing exclusively in middle-market companies in the industrial sector in partnership with management teams.

For more information, please contact John Malloy, Jeff Webb or Sam Adler.

(415) 882-4550


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Select the Right Oxygen Deficiency Monitor for Your Application

When selecting your oxygen analyzer, there many factors to consider for your critical process application.

Oxygen Sensor Types

Today’s oxygen analyzers use one of a several types of oxygen sensors.  As industrial process applications call for improved measurement accuracy and repeatability, users are also demanding analyzers that require a minimum of maintenance and calibration. Users of oxygen analyzers are encouraged to evaluate the merits of a particular oxygen sensor type in context to the application for which it is intended. There is no one universal oxygen sensor type.

The synoptic review of the various gas phase oxygen sensors provided below should be used in conjunction with information gathered from manufacturers of oxygen analyzers. This combination will help to ensure the selection of the right sensor type for the application under consideration.

  • Ambient Temperature Electrochemical Oxygen Sensors
  • Paramagnetic Oxygen Sensors
  • Polarographic Oxygen Sensors
  • Zirconium Oxide Oxygen Sensors

Ambient Temperature Electrochemical Oxygen Sensors

The ambient temperature electrochemical sensor, often referred to as a galvanic sensor, is typically a small, partially sealed, cylindrical device (1-1/4” diameter by 0.75” height) that contains two dissimilar electrodes immersed in an aqueous electrolyte, commonly potassium hydroxide. As oxygen molecules diffuse through a semi-permeable membrane installed on one side of the sensor, the oxygen molecules are reduced at the cathode to form a positively charge hydroxyl ion. The hydroxyl ion migrates to the sensor anode where an oxidation reaction takes place.

The resultant reduction/oxidation reaction generates an electrical current proportional to the oxygen concentration in the sample gas. The current generated is both measured and conditioned with external electronics and displayed on a digital panel meter either in percent or parts per million concentrations.

With the advance in mechanical designs, refinements in electrode materials, and enhanced electrolyte formulations, the galvanic oxygen sensor provides extended life over earlier versions and are recognized for their accuracy in both the percent and traces oxygen ranges. Response times have also been improved.

major limitation of ambient temperature electrochemical sensors is their susceptibility to damage when used with samples containing acid gas species such as hydrogen sulfide, hydrogen chloride, sulfur dioxide, etc. Unless the offending gas constituent is scrubbed prior to analysis, their presence will greatly shorten the life of the sensor. The galvanic sensor is also susceptible to over pressurization. For applications where the sample pressure is > 5 psig, a pressure regulator or control valve is normally recommended.

Paramagnetic Oxygen Sensors

Within this category, the magnetodynamic or “dumbbell” type of design is the predominate sensor type. Oxygen has a relatively high magnetic susceptibility as compared to other gases such as nitrogen, helium, argon, etc. and displays a paramagnetic behavior. The paramagnetic oxygen sensor consists of a cylindrical shaped container inside of which is placed a small glass dumbbell.

The dumbbell is filled with an inert gas such as nitrogen and suspended on a taut platinum wire within a non-uniform magnetic field. The dumbbell is designed to move freely as it is suspended from the wire. When a sample gas containing oxygen is processed through the sensor, the oxygen molecules are attracted to the stronger of the two magnetic fields. This causes a displacement of the dumbbell which results in the dumbbell rotating.

A precision optical system consisting of a light source, photodiode, and amplifier circuit is used to measure the degree of rotation of the dumbbell. In some paramagnetic oxygen sensor designs, an opposing current is applied to restore the dumbbell to its normal position. The current required to maintain the dumbbell in its normal state is directly proportional to the partial pressure of oxygen and is represented electronically in percent oxygen.

There are design variations associated with the various manufacturers of magnetodynamic paramagnetic oxygen sensors. Also, other types of sensors have been developed that use the susceptibility of oxygen to a magnetic field which include the thermomagnetic or `magnetic wind’ type and the magnetopneumatic sensor.  In general, paramagnetic oxygen sensors offer very good response time characteristics and use no consumable parts, making sensor life, under normal conditions, quite good. It also offers excellent precision over a range of 1% to 100% oxygen.

The magnetodynamic sensor is quite delicate and is sensitive to vibration and/or position. Due to the loss in measurement sensitivity, in general, the paramagnetic oxygen sensor is not recommended for trace oxygen measurements. Other gases that exhibit a magnetic susceptibility can produce sizeable measurement errors. Manufactures of paramagnetic oxygen sensors and analyzers should provide details on these interfering gases.

Polarographic Oxygen Sensors

The polarographic oxygen sensor is often referred to as a Clark Cell [J. L. Clark (1822- 1898)]. In this type of sensor, both the anode (typically silver) and cathode (typically gold) are immersed in an aqueous electrolyte of potassium chloride. The electrodes are separated from the sample by a semi-permeable membrane that provides the mechanism to diffuse oxygen into the sensor.

The silver anode is typically held at a potential of 0.8V (polarizing voltage) with respect to the gold cathode. Molecular oxygen is consumed electrochemically with an accompanying flow of electrical current directly proportional to the oxygen concentration based on Faraday’s law. The current output generated from the sensor is measured and amplified electronically to provide a percent oxygen measurement.

One of the advantages of the polarographic oxygen sensor is that while inoperative, there is no consumption of the electrode (anode). Storage times are almost indefinite. Like the galvanic oxygen sensor, they are not position sensitive. Because of the unique design of the polarographic oxygen sensor, it is the sensor of choice for dissolved oxygen measurements in liquids. For gas phase oxygen measurements, the polarographic oxygen sensor is suitable for percent level oxygen measurements only. The relatively high sensor replacement frequency is another potential drawback, as is the issue of maintaining the sensor membrane and electrolyte.

A variant to the polarographic Oxygen Sensor is what some manufacturers refer to as a non-depleting coulometric sensor where two similar electrodes are immersed in an electrolyte consisting of potassium hydroxide. Typically, an external EMF of 1.3 VDC is applied across both electrodes which acts as the driving mechanism for reduction/oxidation reaction.  The electrical current resulting from this reaction is directly proportional to the oxygen concentration in the sample gas. As is the case with other sensor types, the signal derived from the sensor is amplified and conditioned prior to displaying.

Unlike the conventional polarographic oxygen sensor, this type of sensor can be used for both percent and trace oxygen measurements. However, unlike the zirconium oxide, one sensor cannot be used to measure both high percentage levels as well as trace concentrations of oxygen. One major advantage of this sensor type is its ability to measure parts per billion levels of oxygen. The sensors are position sensitive and replacement costs are quite expensive, in some cases, paralleling that of an entire analyzer of another sensor type. They are not recommended for applications where oxygen concentrations exceed 25%.

Zirconium Oxide Oxygen Sensors

This type of sensor is occasionally referred to as the “high temperature” electrochemical sensor and is based on the Nernst principle [W. H. Nernst (1864-1941)]. Zirconium oxide sensors use a solid-state electrolyte typically fabricated from zirconium oxide stabilized with yttrium oxide. The zirconium oxide probe is plated on opposing sides with platinum which serves as the sensor electrodes.

For a zirconium oxide sensor to operate properly, it must be heated to approximately 650 degrees centigrade. At this temperature, on a molecular basis, the zirconium lattice becomes porous, allowing the movement of oxygen ions from a higher concentration of oxygen to a lower one, based on the partial pressure of oxygen. To create this partial pressure differential, one electrode is usually exposed to air (20.9% oxygen) while the other electrode is exposed to the sample gas.

The movement of oxygen ions across the zirconium oxide produces a voltage between the two electrodes, the magnitude of which is based on the oxygen partial pressure differential created by the reference gas and sample gas. The zirconium oxide oxygen sensor exhibits excellent response time characteristics. Another virtue is that the same sensor can be used to measure 100% oxygen, as well as parts per billion concentrations.

Due to the high temperatures of operation, the life of the sensor can be shortened by on/off operation. The coefficients of expansions associated with the materials of construction are such that the constant heating and cooling often causes “sensor fatigue”.  A major limitation of zirconium oxide oxygen sensors is their unsuitability for trace oxygen measurements when reducing gases (hydrocarbons of any species, hydrogen, and carbon monoxide) are present in the sample gas. At operating temperatures of 650 degrees centigrade, the reducing gases will react with the oxygen, consuming it prior to measurement thus producing a lower than actual oxygen reading. The magnitude of the error is proportional to the concentration of reducing gas.  Zirconium oxide oxygen sensors are the “defacto standard” for in-situ combustion control applications.

Other types of oxygen measuring techniques are under development and in some cases being used for specific applications. They include, but are not limited to, luminescence polarization, opto-chemical sensors, laser gas sensors, et al. As these techniques are further developed and improved, they may represent viable alternatives to the major oxygen sensor types currently in use.

Compare Oxygen Deficiency Monitors

Like most things in life, not all oxygen deficiency monitors are the same. There are significant differences in automobiles, lawn mowers, cell phones, as well as in oxygen deficiency monitors.

A number of oxygen moni­tors use what’s referred to as “fuel cell” oxygen sensors. Fuel cell oxygen sensors typically require replace­ment every 10-14 months. But that’s only half of the problem. The issue is that as fuel cell sensors age, their respective electrical outputs diminish over time (similar to a flashlight battery). This reduction in out­put mimics a low oxygen signal to the electronics. If the drop in output is significant enough, it will result in a false low oxygen alarm. Typically, with the first few false low oxygen alarms, the reaction by personnel is to treat them as actual low oxygen alarms and clear the areas in question. As these false low oxygen alarms increase in frequency, it often leads to frustration on the part of personnel, and may create a po­tentially dangerous scenario. Employees begin cancelling the audible alarms assuming they are false, when in fact they may be real low oxygen events. Cases have been documented where employees have gone as far as to permanently disable the monitor’s audible alarms due to the “nuisance factor”. Is it worth taking the risk with fuel cell oxygen sensors?

Frequent exaggerations are being made on the part of certain suppliers of zirconium oxide based oxygen deficiency monitors. Claims that the zirconium oxide sensors are calibration free for 10 years plus! One should ask why aren’t these same manufacturers offering a 10 year sensor warranty? Ironically, one of the major Japanese suppliers of the actual zirconium oxide sensor used in many of these monitors makes no such spurious claims. Upon closer examination, customers find a much different story is told when they read the instruction manual for many of these zirconium oxide oxygen monitors. One manual states, “as the oxygen sensor ages over time, it may require adjustment to 20.9%. The 02 monitor also requires pe­riodic testing with nitrogen to verify the cells response to 0% oxygen”. The manual goes on to detail how to make the adjustments (AKA calibration) to the monitor. As the old adage says, “if it sounds too good to be true, it probably is”. Trained safety personnel both understand and agree that gas monitors used to help protect personnel require occasional checks. The stakes are significant.


Series 1300 Oxygen
Deficiency Monitor
Fuel Cell Oxygen Monitor
High Temperature (450 °C) Zirconium Oxide Oxygen Monitor
Three-year warranty on both the electronics and      sensor


NO – Typically one year

NO – Typically two years

Accepts up to 3 oxygen sensors with one set of electronics drastically reducing the per point monitoring costs





Built-In data logger standard



Limited Availability

Easy field replacement of the oxygen sensor



NO – Both sensor and mating electronics need replacement – an expensive repair

Built in alarm relay contacts

YES (4 Standard)

Some at extra charge

Often an extra charge

Can be affected by changes in ambient air now caused by HVAC / air handling systems



YES – Changes in airflow may sufficiently cool the high temperature sensor producing erroneous oxygen readings.

Can be used in the presence of combustible gases, refrigerant gases, other reducing gases




Long-life oxygen sensor



Can fail prematurely from heat fatigue

Practical Considerations for Quantitative Gas Analysis with Quadrupole Mass Spectrometers

Practical Considerations for Quantitative Gas Analysis with Quadrupole Mass Spectrometers

Many factors must be considered when comparing the overall suitability of different quadrupole-based gas analyzers for any given application and the list can sometimes appear daunting and confusing. This can be due to inconsistencies in the way that different manufacturers choose to define specifications or, in some cases, omit them altogether.

These factors can be categorized into two main areas: (i) inlet interface suitability and (ii) quadrupole mass analyzer suitability. This article aims to remove some of this confusion and define and present those practical specifications which are critical for repeatable and reliable quantitative gas analysis.

The suitability of the inlet and interface determines how well the gas analyzer can capture, condition or transfer the gas sample without altering it and for it to be measured on an appropriate timescale, which could be milliseconds or hours. The inlet and interface can include both the upstream transfer elements and the downstream pumping and gas handling elements.

Quadrupole Mass Spectrometer
Assuming the inlet and interface are properly designed and equal between systems, then the quadrupole mass spectrometer is the critical element determining the overall precision, stability, and detection limits of the gas analyzer. The quadrupole mass spectrometer includes the ionization method, the transmission characteristics, and the quality of the driving electronics.

Precision, stability, and detection limit are often mis-represented in commercial literature. This misrepresentation can be addressed and clarified by directly comparing two different classes of quadrupole analyzers: a 6mm rod diameter, RGA type instrument, typical of many currently on the market, and a higher performance 19mm rod diameter instrument, used in more demanding research and industrial applications. These two systems are compared with nominally identical inlet/transfer conditions, so that only the mass spectrometer performance is under consideration. This presents a direct comparison of the practical range of precision, stability and detection limit in each case so potential users of this powerful analytical technique may be better equipped to make meaningful comparisons between different suppliers.

The MAX300-CAT is typical of the high-end RGA based gas analyzers, based upon 6mm quadrupole rod technology, whereas the MAX300-LG is a higher performing analyzer based on 19mm quadrupole rod technology and more sophisticated electronics.

Detection Limit Comparison
The specified figure of detection limit can be very misleading. Often it will be a calculated figure, or it may reflect data that has been averaged and smoothed for long periods of time to give a best possible case which is often not achievable in practical situations. Nonetheless, the ultimate detection limit is a good starting point to begin to define the practical capabilities of the analyzer.

Speed of Analysis
Analysis speed is a key factor in quantitative gas analysis. Applications such as catalysis, reaction monitoring or kinetics, and evolved gas monitoring all require faster capture of process changes than QA/QC applications, while a breath measurement application needs to report quantitative differences on the millisecond scale. Note that this refers to the ability of the analyzer to measure, with the desired level of accuracy, raw signals and then analyze these in a given timeframe, taking into account spectral interferences, in order to output the result of a single analysis. The rate at which an analyzer scans directly influences this data quality. Slower scanning or more averaging yields more repeatable results and lower detection limits.

Analysis Precision
Analysis precision (or short-term repeatability) represents the standard deviation of analysis results over short time periods. Repeatability can be improved by slowing analysis scan speed or averaging more scans.

Analysis Stability
Analysis stability is a representation of drift or fluctuations over long-term data collection. It is a critical factor which influences longer analyses such as process control, slow heating TGA and thermal analysis, and air monitoring, but also impacts general instrument operation. Stability allows for accurate results over time, less calibration frequency, and confidence in the day-to-day repeatability of the analyzer.

Dynamic Range
Large dynamic measurement range is an essential requirement of quantitative gas analysis and becomes especially apparent in applications such as solvent drying, where species must be monitored from high to low concentrations with accuracy and repeatability.

The MAX300-CAT, a high-end RGA based gas analyzer using 6mm quadrupole rod technology, can demonstrate low detection limits of approximately 5 ppb, using slow scan speeds. The scan speed on this instrument can be increased to a typical quantitative analysis rate of 2 seconds per component, resulting in an increase of detection limits to 0.5 ppm. The MAX300-CAT has a maximum speed of approximately 2-seconds per component in quantitative scans. While this changes the instrument precision, the stability remains constant. The dynamic range of the MAX300-CAT allows for an analysis range from 1×10-6 to 5×10-13 Torr (100% to 0.5 ppm), when scanning at a rate of 2 seconds per analysis component.

The MAX300-LG, a higher performing analyzer based on 19mm quadrupole rod technology and more sophisticated electronics, displays extremely low detection limits of <1 ppb, using slow scan speeds. The scan speed on this instrument can be increased to a typical quantitative analysis rate of 400 milliseconds per component, resulting in a moderate increase of detection limits to <10 ppb. The MAX300-LG has a maximum speed of 5 milliseconds per component in quantitative scans. This instrument has incomparable precision and stability, a result of the large quadrupole and high-performance electronics combination. The MAX300-LG demonstrates a very large dynamic range from the dual detector setup, allowing an analysis range of 1×10-6 to <1×10-14 Torr (100% to <10ppb), while scanning at a rate of 400 milliseconds per component.

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Using a Mass Spec in Semiconductor Fabrication

Consider Using a Mass Spec in Semiconductor Fabrication

Ultra-pure gases are a necessity for semiconductor device fabrication and the continuous monitoring of bulk gas purity can ensure maximum production. Contamination is costly. Semiconductor manufacturers need the ability to continuously verify the purity of process gases in real-time and detect trace contamination at concentrations in the low parts-per-trillion (ppt).

Our ultra-high purity gas analyzers have the speed, sensitivity, and ease-of-use to continuously monitor Nitrogen, Argon, Helium, Oxygen, and Hydrogen supply streams and rapidly report ppt-level contamination to protect the electronics fabrication process. The Process Insights VeraSpecAPIMS combines Atmospheric Pressure Ionization (API) technology with a high-performance mass spectrometer optimized over five decades in industrial gas analysis. Process Insights is the only mass spectrometer manufacturer in the world that utilizes a 19mm, tri-filter quadrupole mass filter in semiconductor gas analysis for the very best performance, reliability, and uptime.


  • Confident supply of UHP production gases
  • One analyzer for all contaminants
  • Fully automated, real-time contamination alerts
  • Reliable 24-7 process protection
  • Maximized wafer yields

Atmospheric pressure ionization is a technique that gives a mass spectrometer the very highest sensitivity for trace gas analysis in UHP samples. A corona discharge needle is used to ionize the molecules of the bulk gas sample. These ions readily transfer this charge to contaminant molecules with lower ionization potentials. The approach yields ionization efficiencies approaching 100%, ensuring exceptional detection limits.

VeraSpec APIMS for Continuous Semiconductor Bulk Gas Purity Verification

While APIMS allows for high ion currents, resulting in low detection limits, the technique is limited to species whose ionization energy is less than that of the bulk gas, or components with sufficient proton affinity to be ionized. The VeraSpec APIMS system combines both EI and API ionization sources. Having two ionization techniques allows for the complete analysis of all components in the pure gas sample with one system.

The Questor5 process control software that drives the VeraSpec APIMS System is designed for continuous gas monitoring in a process environment. The intuitive web-based interface allows the user to check instrument status, review data, or run an acquisition from anywhere on the network, while maintaining government and industry security standards for login and electronic record keeping.

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Validating CRDS for Moisture Analysis in Medical Oxygen

Validating CRDS for Moisture Analysis in Medical Oxygen

Medical oxygen is one of the most commonly used gases in the healthcare industry, from giving O2 to critical care patients, providing the basis for anesthesia, to supplementing O2 to patients with chronic lung diseases, such as COPD.

To ensure that the oxygen meets the necessary quality to prevent harm to patients, strict standards outline limits to a variety of possible impurities in the gas, one of them being water vapor (H2O). One of the most common standards for medical oxygen is the European Pharmacopeia (EP) standard, we will demonstrate analytical equivalency between the Process Insights’ Tiger Optics’ Spark Cavity Ring-Down Spectroscopy (CRDS) analyzers and demonstrate analytical equivalency to traditional electrolytic moisture analyzers, so the Spark can be used as a more modern and powerful alternative.

Proving Equivalency to European Pharmacopeia
The EP standard dictates that the maximum water vapor content in medical and pharmaceutical grade gas must be less than 67 parts per million (ppm), and the recommended method for analysis of moisture content in medical gases is electrolytic based sensors. Since this standard was published in 1999, gas manufacturers have significantly improved their process efficiency, resulting in considerably higher purity product; at
the same time, the state-of-art in analytical technologies for moisture measurement has evolved. The combination of improved analytical capabilities and higher purity product creates an opportunity for gas manufacturers to maximize the return on oxygen by qualifying it for multiple uses in a single validation step.

Based on powerful, proven CRDS, the Process Insights‘ Tiger Optics Spark H2O offers a wide dynamic range, from single-digit parts-per-billion to one thousand ppm for analysis of moisture in oxygen. This low-cost, fast and accurate analyzer features self-zeroing and auto-verification, eliminating the need for field calibration and saving time & money on labor and consumables. In addition to qualifying oxygen, the same analyzer can service nitrogen, argon, helium, hydrogen, clean dry air, and many other gases and mixtures. In support of the proposed use of the Tiger Optics Spark for qualification of medical oxygen, we present the following validation data, demonstrating equivalency in accuracy of the Spark H2O with two EP-approved electrolytic moisture analyzers.

The Tiger Optics Spark analyzer allows accurate measurement of moisture in oxygen to within ±4% or 6 ppb, whichever is greater, as clearly demonstrated in the present validation data. Thereby, it demonstrates equivalency with the European Pharmacopoeia standard, which mandates a relative accuracy of less than ±20%. Plus, the Spark affords a significant performance advantage over the incumbent electrolytic based sensors, including lower detection limits, wider dynamic range, higher accuracy, and faster speed of response. This allows for better throughput and simplified product qualification, ultimately saving end-users time and money. It should be noted that the ability to conduct one-step qualification of pure oxygen for multiple applications provides significant value to users.

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Accurate Online Analysis of Helium Tube Trailer Filling

Industrial gas manufacturers package and deliver gases in a variety of different ways. These include on-site pipeline distribution, bulk delivery of liquefied gas into an on-site bulk container, exchange programs for large, compressed gas vessels (i.e., tube trailers), and delivery of smaller cylinders containing gas or liquefied gas.

Each delivery mechanism has unique advantages, but also unique associated costs. Here we describe the requirements and challenges of tube trailer filling, detailing the needs related to filling high purity Helium into tube trailers and showing that our Tiger Optics Spark H2O analyzer can offer a perfect solution for detecting trace moisture in this application.

Challenges of Helium Filling
Helium tube trailer filling is a demanding activity with relatively high cost and process complexity. “Crude” Helium is harvested in geographic locations that have Helium-rich natural gas fields, which mostly include areas in Algeria, Australia, Canada, Poland, Qatar, Russia, and the United States. It is delivered to industrial gas packaging facilities around the world as a bulk cryogenic liquid in 11,000-gallon refrigerated ISO tankers. The bulk liquid is not thermodynamically stable and must be quickly and efficiently transferred to more stable product forms (i.e.,
pressurized gas) with longer storage potential. This is typically accomplished by decanting off some of the liquid into smaller Dewar vessels for immediate sale and use and gasifying and compressing most of the Helium for filling pressurized vessels (compressed gas cylinders and “tubes”).

In recent years, Helium has become short in supply numerous times. As a result, Helium prices have doubled in the last decade and are routinely exceeding $200 per thousand standard cubic feet (SCF). Therefore, efficient management of Helium processing and minimization of product loss directly affects the profitability of the enterprise. Additionally, Helium tube trailer filling is a time-consuming process, taking at least 14 hours for a successful fill of the largest tube bundles (180,000 SCF). With respect to other activities at packaged gas facilities, a relatively large investment in time and product value is made for Helium tube trailer products.

Typical Helium tube trailer filling operations perform several steps including gasification, compression, purification, and tube filling (schematically outlined in Figure 3). The goal is to fill the trailer tubes in the most energy and time-efficient manner possible, and there are several points were making a fast, accurate moisture measurement can assist in achieving this goal.

The major monitoring points of interest are:

  • Incoming Helium Product: Incoming crude Helium is typically too wet to be packaged without some purification. Moisture measurements made on the crude Helium allow optimization of purification procedures.
  • Post-Purification: Purification processes typically include a selective adsorptive bed that can saturate with moisture and other impurities. Once saturated, the bed loses its capacity to retain any additional moisture and it must be regenerated. The active lifetime of the bed is a function of the moisture level in the incoming gas stream and the total time of usage. Monitoring the purification system output stream helps to indicate the active lifetime of the bed between regenerations.
  • Tube Trailer Inlet: Most crucially, monitoring of the Helium product as it enters the tubes assures that the tube trailer is filled within specification product. Moisture measurements made at the point of fill will detect any quality defect stemming from bad product, inadequate
    purification, or compromised transfer lines. Since the fill is accomplished over such a long period of time, small variations in the moisture levels can indicate to an operator that minor process adjustments should be made. For example, an upward-shifting moisture level could indicate that the purification must be slowed, to better extract the moisture.

Traditional moisture measurement technologies have some drawbacks for these applications. Most demonstrate slow response time, limited range, and a high degree of signal averaging, which can miss a moisture excursion. At minimum this can lead to energy waste in the process, and in the worst case an entire tube trailer can be filled without specification product due to a missed moisture spike.  Lack of ability to change sampling points is another issue with traditional technologies. To switch from crude product to purification or final fill sampling points, the analyzer needs to be disconnected and the inlet exposed to ambient for a short period. Most technologies would experience saturation in this situation and take hours or even days to dry down again sufficiently to perform the next measurement.

Improving Measurement with the Spark
For each of the measuring points highlighted above, the Process Insights’ Tiger Optics’ Spark H2O analyzer is optimally suited to make the measurement. The absolute accuracy offered by Cavity Ring-Down Spectroscopy (CRDS) is a key advantage. There is also no requirement for a zero gas or a span gas.

Flare Compliance at Oil Refineries

Flare Compliance at Oil Refineries

EPA Refinery Sector Rule (RSR) 40 CFR 63 Flare Gas Compliance with Total Composition Monitoring

January 30, 2019 is the compliance deadline for the latest update to the US EPA Refinery Sector Rule (RSR). This will require additional monitoring and gas analysis when regulated material is sent to the flare. The MAX300-AIR, environmental gas analyzer, provides a rapid, speciated analysis of vent gas composition that many refineries are currently using for EPA compliance. According to new requirements in the General Provisions, flares used as Air Pollution Control Devices (APCD) are expected to achieve 98% Hazardous Air Pollutant (HAP) destruction efficiencies. These updated requirements include monitoring of the pilot flame, visible emissions, flare tip velocity, net heating values, and dilution parameters, as well as maintaining a Flare Management Plan and a Continuous Parameter Monitoring System Plan.

The Net Heating Value of the gas in the Combustion Zone (NHVCZ) is of particular importance as it has a direct impact on combustion efficiency. As a result, the RSR update mandates a NHVCZ ≥ 270 Btu/scf, based on a 15-minute block average, when regulated material is sent to the flare for at least 15 minutes. For flares actively receiving perimeter assist air, NHVdil must be greater than or equal to 22 Btu/ft2, when regulated material is sent to the flare. To meet this requirement, continuous direct measurements of refinery vent gas must be made. High variability, sulfur content, and corrosivity can make these samples difficult for many analytical techniques.

The MAX300-RTG 2.0 real-time gas analyzer is currently used at many US refineries for NSPS Subpart Ja sulfur monitoring. The analyzer measures the full, speciated composition of the flare gas and delivers continuous updates of NHV, H2S, and Total Sulfur several times per minute (Fig. 1). Rapid updates of NHV are critical for compliance because the refinery must be able to both monitor and control the gases at the flare tip within the regulated 15-minute block. The additional information provided by full speciation can be used at RSR sites for Ja sulfur compliance, validating or replacing existing sulfur analyzers, as well as for operational control and accurate root cause analysis.

The regulation provides multiple ways to calculate the Net Heating Value of the gas in the Combustions Zone (NHVCZ) for RSR reporting, but all methods use the Net Heating Value of the Vent Gas (NHVVG) as an input. In fact, several parameters, including NHVCZ, NHVdil, and each flare’s specific maximum tip velocity (Vmax), are determined based on NHVVG, making this value one of the key components of reporting compliance and effective flare control. Direct measurements of vent gas composition can be used to calculate NHVVG and high precision gas analysis ensures accurate, actionable NHVVG data (Table 1). When regulated material is sent to the flare, NHVVG changes dramatically as hydrogen and hydrocarbon concentrations in the stream spike and recede. Regardless of the BTU content of the sample, the MAX300-RTG maintains constant, high precision on the NHV parameter due to the inherent repeatability of the gas analysis.

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Fenceline, Air & Flare Gas Monitoring

Fenceline, Air & Flare Gas Monitoring

Environmental Applications for Real-Time Mass Spectrometer Gas Analyzers

By Chuck Decarlo, Business Development & Marketing Manager

See how the recent updates to 40 CFR 60 and 63 have increased EPA regulation of flare gas and fenceline monitoring requirements is prompting the need to adopt real-time gas analysis solutions at many sites, ranging from oil refineries to downstream hydrocarbon manufacturing.

Industrial mass spectrometers provide fast, continuous updates of the necessary compliance parameters as well as additional information for overall process safety and control. This presentation showed many examples and data from fenceline, flare gas, fuel gas and air monitoring environmental applications using a real-time, mass spectrometer gas analyzer.

Mass spectrometry is an analytical technique that utilizes the molecular mass of substances for identification and quantitation. Gas and vapors are ionized inside a vacuum chamber. The ions are then filtered using electric fields generated by the quadrupole. Ions of a particular mass are selected to go to the detector. The composition of the gas sample is calculated from measured ion current and reported to the user in real-time.

By its very nature, a mass spectrometer is a generalist: there is no class of molecules that is unable to analyze and it’s fast.   Also, if you have to measure 80 or 100 sample points spread throughout your facility that would mean many dedicated analyzers, and all of the required maintenance.  A mass spec can do it all.

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Why Controlling The Temperature of the Sample Interface Matters


Some applications such as nucleation reactions, polymer cross-linking or high viscosity fluids require that the temperature of the fluid be precisely controlled to ensure that the reaction proceeds as expected and passes through the flow cell. If the temperature drops, the fluid may solidify in the flow cell or the polymer chain may not be the correct length.

You Need To Consider A Temperature Controlled Flow Cell for At-Line FT-NIR Measurements

Our Guided Wave Multi-Purpose Flow Cell (MPFC) that is compatible with NIR and UV-VIS Analyzers is available with internal tubing for heating or cooling fluid. While the heat exchanged is not sufficient to impact a rapidly flowing sample, it can be used to maintain the temperature of a preconditioned sample.  A version of the MPFC, drilled to accept a heating or cooling fluid, is also available. While the heat exchanged is not sufficient to significantly impact a rapidly flowing sample, it can be used to maintain the temperature of a preconditioned sample.

The MPFC provides exceptional optical performance and is optically matched to all our Guided Wave analyzers Typically, peak transmission exceeds 50%. That means more signal, lower measurement noise translating to lower limits of detection.

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