Amine treatment is a process typically used for Hydrogen Sulfide removal from natural gas (sour gas). This operation is commonly referred to as gas “sweetening," acid gas removal, or amine scrubbing

Amine units are used all over the world in oil refineries and gas plants to remove hydrogen sulfide (H₂S) from a product stream. New environmental standards are more strict and require ever-decreasing contents of H₂S in clean natural gas. Most of the new sources of oil and gas discovered today have high contents of H₂S which demand more efficient removal technologies (the Shah Gas field in the United Arab Emirates for example has up to 30%  H₂S).

The Challenge of Amine Units in Harsh Chemical Environments

Amine units operate under harsh chemical environments. H

Kalrez Spectrum 7275 is a perfluoroelastomer that provides long life sealing in an array of aggressive chemical environments that typically make sealing difficult: ethylene oxide, acrylic monomers, silanes and chlorosilanes, and strong oxidizers such as nitric acid, chlorine and chlorine dioxide.

It has demonstrated improved chemical and compression set resistance and mechanical property retention when compared to competitor’s elastomers.

Kalrez Spectrum 7275 is based on a proprietary cross-linking system, and is uniquely identified by its light brown shade.

Targeted applications include industries that depend on mechanical seals, pumps, valves, compressors, filtration columns and analytical equipment for their critical processes.

Success Story: Kalrez® Spectrum™ 7275 Double Seal Life in Chlorine Dioxide Service

Chlorine dioxide is a strong oxidizing gas that finds many uses as bleaching agent

High Performance Seals for Polycrystalline Silicon Process Equipment

The Challenge

To meet growing demand in solar cells, the Siemens* process is used to produce highly purified polycrystalline silicon by thermally decomposing tri-chloro-silane (TCS). The reactors employed require three kinds of high-performance seals in the following locations: A) bell jar seals; B) electrode seals between the electrode and ceramic inlet; and C) a gasket for the view port seal (see schematic).

Application Details

The process involves a very hot, dry environment with temperatures up to 1200°C (2100°F). Sealing components see up to 300°C (572°F). Process media include TCS and aggressive by-products of its decomposition, such as HCl gas. Superior compression set performance is needed for effective sealing and extended seal life. Very low outgassing is a key requirement for preventing contamination of the process environment.

The presence of harsh chemicals in high temperature conditions often require an upgrade from standard sealing materials to PTFE or fluoroelastomers (FKM) to improve thermal stability and chemical resistance. However, PTFE can deform and creep “hot flow” in the bell jar seal increasing the risk of product loss. FKM, with its high temperature rating of 200°C (392°F), also has deficiencies in this 300°C (572°F) environment.

The Solution and Key Advantages of Kalrez PV8070

Kalrez PV8070 perfluoroelastomer parts installed as washers and gaskets in reactors for the Siemens CVD process have demonstrated outstanding performance in this demanding application. Kalrez® PV8070 parts are effective seals that provide:

DuPont™ Kalrez® 1050LF perfluoroelastomer parts are a carbon black-filled general-purpose product for o-rings, seals, and other parts used in chemical process industries. It is a classic-grade and longtime favorite for premium performance and provides a more economical option than similar compounds such as 7375.

Kalrez 1050LF o-rings can maintain their recovery with elasticity following high-pressure applications, maintaining a tighter seal for longer periods of time compared to other compounds. With a pressure rating of 1,500 PSI, it can help extend seal life and integrity, ultimately lowering costs.

With above-average hot water and steam resistance, the maximum application temperature for 1050LF is approximately 550°F (up to 288°C). This compound is also known for its excellent amine resistance and

Article re-posted with permission from Parker Hannifin Sealing & Shielding Team.

Original content can be found on Parker’s Website and was written by Nathaniel Reis, Applications Engineer for Parker O-Ring & Engineered Seals Division.

In our semiconductor entry from last month, we noted that lowering the cost of ownership is a multi-faceted goal. We discussed how one of the areas for potential improvement

Article re-posted with permission from Parker Hannifin Sealing & Shielding Team.

Original content can be found on Parker’s Website.

Oil & Gas Sealing Solutions with a Low Temperature FFKM

Technology advancements and new-to-world discoveries are constantly creating a new series of challenges for seal materials in the Oil and Gas industry. In today’s environments, seals are being pushed to perform in temperature, pressure and chemical extremes never before thought to be obtainable with rubber products. Application pressures exceeding 20,000 psi, service temperatures ranging from -40°F to upwards of 500°F, and exposure to some of the most aggressive media on the planet are placing immense amounts of stress on sealing elements. Parker’s FF400-80 compound has been formulated to provide a solution to all of these sealing challenges.

FF400-80 Compound - FFKM Product Features

• Temperature range: -40° to 527°F
• Best-in-Class low-temperature FFKM
• Excellent compression set resistance
• RGD resistant per ISO 23936-2 and TOTAL GS EP PVV 142
• Sour service H₂S resistant per ISO 23936-2
• Maintained resilience at high pressures and low temperatures
• Great for use in HTHP applications

Sounds great, but what's the catch?

The Challenge

By switching from gasket seals of PTFE to custom gaskets of DuPont™ Kalrez® perfluoroelastomer parts in the sensor head of a process instrument refractometer used by the food, pulp and paper and chemical industries, process instrument manufacturer K-Patents Oy, Vantaa, Finland, was able to dramatically extend instrument service life, increase reliability and safety, and reduce costs for the company and its customers.

The Solution

Aggressive environment
Through permanent in-line fluids immersion, K-Patents’ “PR-01-S” refractometer is exposed to temperatures      from –20 ° to +220 °C, pressures from –0,7 to +25 bar, and some 500 process fluids and chemicals, many of which are extremely aggressive. Delicate digital detector circuits and fiber optics in the sensor head are sealed by two gaskets from attack by aggressive fluids. Because of inherent inelasticity, the original PTFE gaskets could not withstand the dynamic temperature fluctuations of many food, pulp and paper and chemical manufacturing processes, creating a leak path allowing process media to enter and damage the device. As a result, costly replacement of the PTFE seal became necessary approximately every 6–12 months.

Article re-posted with permission from Parker Hannifin Sealing & Shielding Team.
Original content can be found on Parker’s Blog.

Semiconductor FFKM Offers Low Particle Generation AND Extreme Etch Resistance

In the world of semiconductor manufacturing, performance requirements are driving circuit sizes smaller and smaller, causing increased sensitivity to wafer defects. In parallel, the number of manufacturing steps has also increased driving a need for improved tool utilization and leaving more opportunity for these defects to be introduced. Identifying and eliminating the sources of defects is a tedious but necessary process to improve wafer yield.

What impact does seal contamination make?

One very distinct source of defects are the seals within a fab’s tool. Plasmas involved in both deposition, etch and cleaning processes utilize aggressive chemistries that put even high-functioning perfluorinated sealing compounds to the test. Much room for improvement has been left in this industry with many seal materials still posing significant threats to defectivity or downtime despite being designed for low particle generation or etch resistance.

How can Parker ULTRA^™ change the industry?

Parker’s Ultra^TM FF302 Perfluorelastomer has proven success in CVD and etch applications, putting this material at the top of its class.  Typically, seal materials for semiconductor applications are optimized for low particulation or extreme etch resistance, however, Ultra FF302 provides both attributes in one material.  Laboratory testing shows Ultra FF302 has lower erosion in aggressive plasma chemistries even when compared to today’s leading elastomeric materials (Figure 1 below shows comparison erosion levels of various etch resistant perfluoroelastmers after exposure to O₂ plasma).

Gallagher recently released our High Performance Elastomer Seals for the Instrumentation Industry White Paper.  This was written by Russ Schnell, an Elastomer Consultant contracted by Gallagher Fluid Seals, and a former Senior Application Engineer with the Kalrez® perfluoroelastomer parts business at DuPont.  This white paper is now available for download on our Resources page.

Below is the third and final section of the white paper, which will discuss the importance of proper seal and groove design.

Proper Seal & Groove Design

Proper seal design is a necessity for elastomer seals to perform reliably over the long term. Many of the instrument applications mentioned above use o-ring seals. The suggested compression for an elastomer o-ring seal to perform properly is typically a minimum of 16%, and a maximum of 30%. However, this range must also take into account the thermal expansion of an elastomer at elevated temperatures as well as any swell due to chemical exposure. Many of the elastomer seals used in instruments are small o-rings, which can create design issues. This is especially true for perfluoroelastomer parts which have a relatively high coefficient of thermal expansion (CTE). Fluoroelastomers have a lower CTE, making seal design easier at elevated temperatures.