AAI’s Complete Solution to Analysis of Total Sulfur and BTEX–Rising Volume of Natural Gas Exportation Requires Compositional Analysis and Control

LNG Process

Natural gas production has surged over the last decade with the discovery of large new gas wells and gas plant expansions. The abundance of natural gas reserves has led to low domestic trading prices and a need to export for all major natural gas producing countries. Natural gas is also viewed as a placeholder as political agendas are pushing for less reliance on coal and development of renewable energy technologies. U.S. News forecasts a “20% increase in demand for U.S. natural gas by 2020”. The U.S. is expected to be the third largest exporter of LNG by the end of the decade only behind Australia and Qatar.

For transportation and storage, natural gas is cooled and compressed into a liquid called liquefied natural gas (LNG). There is about a 600:1 volume change from gas phase to liquid phase which equates to more efficient use of storage and transportation resources for exporters. Contaminants in natural gas which need to be removed prior to liquefaction include Total sulfur and BTEX.

Increasingly strict reporting regulations and tariffs on the sulfur content of sales quality natural gas has boosted the need for analyzers with a fast response time and multi-component measurement capabilities. In addition, natural gas process producers often need to comply with contractual pipeline agreements and are interested in corrosion prevention on their liquefaction equipment.

Benzene, toluene and xylenes (BTEX) in pre-liquefied natural gas readily freezes at the cold temperatures required in the liquefaction process. The liquefaction equipment can become blocked or coated by these solids which requires shut down for maintenance. As a preemptive measure, LNG producers remove BTEX from the natural gas before liquefaction. Validation of the BTEX concentration in pre-liquefied natural gas ensures efficient BTEX removal to protect downstream equipment.

Applied Analytics offers an automated and continuous measurement solution for monitoring total sulfur and BTEX in pre-liquefied natural gas. Our equipment is designed with a focus on high accuracy, low maintenance and a fast response time. The OMA-300 is a complete solution for monitoring H2S, COS, MeSH, and EtSH to sum to a total sulfur measurement and determining BTEX concentrations in pre-liquefied natural gas.

Please see our video demonstrations of the applications:

Demo: Sulfur Measurements in Natural Gas

Demo: BTEX Measurements in Natural Gas

For more information on all our products and applications, please contact our sales team.

Natural Gas & The Smell of Safety

natural gas and the smell of safety

Why measure odorant level in natural gas?

Unlike modern industrial zones, where safety regulations demand constant monitoring of ambient gases, people in residential areas typically have only one recourse for detecting natural gas buildup: their noses.

On its own, natural gas is technically odorless. The distinctive smell is artificially added solely for the purpose of human detection: US law, for example, requires that all natural gas be detectable by a human with a normal sense of smell when the gas concentration exceeds 1/5 of its lower explosive limit (LEL), i.e. well below the threshold at which natural gas can ignite in air.

To odorize the natural gas, distribution companies inject chemical odorants (typically blends of mercaptans) into their pipeline system. This injection is a sensitive procedure: too little odorant makes the gas unsafe for distribution, but too much odorant makes the product overly unpleasant and wastes resources.

In order to monitor the odorant level in natural gas, distributors have traditionally dispatched designated “sniffers” – humans who sniff gas samples and assess odor rating at a specific pipeline sampling point. Aside from being an unhealthy practice, this method is imperfect because sniffers are subjective; humans can have inconsistent olfactory response due to diet, sickness, or developed tolerance. Even the most objective sniffers will be thwarted by chemical phenomena in the pipeline such as adsorption or odorant fading/masking.

The future of odorant analysis

With safety regulations growing increasingly stringent, many pipeline operators are turning to modern analytical methods to supplement or replace the human sniffer method. Using dispersive UV-Vis absorbance spectrophotometry, the OMA-300 measures the concentration of up to 5 odorant species simultaneously in a continuously drawn natural gas sample.

Critical advantages of the OMA over human sniffing include (1) objective analysis normalized regularly by Automatic Zero; (2) 24-hour analysis for rich trend data; (3) fast response to sudden changes in odorant level; (4) reduced exposure of humans to toxic samples; (5) reduced cost of operation by slashing travel time and workload of human sniffers.

The safety of OMA

Watch this video demo which explains why the OMA is the world’s safest online analyzer for toxic sulfur compounds such as the species monitored in odorant analysis.

More information
1. Application Note   2. OMA Series 

Our Tail Gas Probe v3 Now Available!

Tail Gas Probe v3

Since 2014, we have been field-testing a major update to the probe design for our TLG-837 Tail Gas Analyzer — the most trusted H2S/SO2 ratio monitor in the sulfur recovery industry. We are excited to announce the official launch of DEMISTER Probe v3!

The New Isolation Valve

On previous probe versions, the ball valve allows the user to retract the probe from the process pipe to perform maintenance. In DEMISTER Probe v3, we introduced a bonnet-style shutoff valve directly in the probe head with which you can internally seal the process at the sample entrance port. This safe, quick method to access the sample flow cell completely eliminates the need to retract the probe during maintenance!

Our case studies exceeded our own expectations: engineers reported that the maintenance procedure of cleaning the optics (recommended monthly) is 75% faster when using the isolation valve than when retracting the probe.

Redesigned Cooling Extensions

On the TLG-837, the cooling extensions increase the distance between the fiber optic collimators and the flow cell, protecting the optics from damage due to conductive heat transfer. Thanks to user feedback, we relocated the sealing o-rings from the probe head to the body of the removable cooling extension itself, making them much more accessible for routine inspections. Don’t worry — the new cooling extensions retrofit into all of our previous DEMISTER Probe versions.

No other tail gas analyzer manufacturer takes the needs of the user as seriously as we do. We are now shipping the best version of the safest, most advanced tail gas analyzer in the world.

Get in touch with us today to learn more about DEMISTER Probe v3.

OMA InGaAs version released! Many new applications including Wobbe Index

ingaas-news-release-artwork-v7-same-guy-800px

We’re proud to announce the new InGaAs version of the highly successful OMA analyzer platform, adding hundreds of measurement applications to the OMA’s domain. The first product to use this technology is the OMA Wobbe Index Analyzer, the world’s only all-optical solution for measuring interchangeability of natural gas.

InGaAs Technology

The infrared-range sensor inside the InGaAs OMA capitalizes on recent major advancements in InGaAs (indium gallium arsenide) semiconductor technology to provide accuracy equivalent to gas chromatography at far lower manufacturing costs and operational complexity. Joining the UV-Vis and the SW-NIR versions of the OMA, the InGaAs model monitors real-time sample absorbance from 1550 to 1850 nm, targeting alkane hydrocarbons and other molecules that were previously out of reach for the OMA platform.

The New OMA Wobbe Index Analyzer

One of the major verified applications for the new InGaAs-driven system is the online measurement of Wobbe Index in natural gas, which allows operators to quickly determine the interchangeability of gases. This measurement has historically been performed through residual oxygen analysis, a complex method involving burning precise amounts of the sample fluid and measuring the unused oxygen to indirectly derive the Wobbe number.

The OMA Wobbe Index Analyzer shifts the paradigm for this application as the first entirely optical solution: the system measures the concentrations of each Wobbe-contributing component in the natural gas (typically methane and ethane) and directly derive the gas density as well as the real-time Wobbe number.

Since most conventional Wobbe Index monitors on the market are designed and priced very similarly to Applied Analytics’ own legacy CVA-100 model (combustion-based), the OMA Wobbe Index Analyzer’s performance was benchmarked against this system during development. Under eligible stream conditions, the OMA provides superior accuracy and faster response time than the CVA-100, promising a more reliable measurement at a fraction of the end user price.

Get an Inside Look at our Patented DEMISTER Probe Technology

TLG-837 DEMISTER Sampling Probe Animation

In a new demo from our design department, we answer some common questions about one of our most innovative products: the sulfur mist-removing DEMISTER Probe.

This device solves a very specific and persistent problem in sulfur recovery optimization: how do you obtain a sample from Claus process tail gas without sulfur mist plugging your instrument? Our demo will show you how our in situ probe uses steam to selectively condense elemental sulfur right at the tapping point, eradicating the problem of sulfur mist.

Continue reading “Get an Inside Look at our Patented DEMISTER Probe Technology”