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 A Special Applications Report by David Wolff, Proton OnSite
Independent industrial gas distributors fill a critical niche in the industrial gas market by providing superior service to customers. With highly personal attention and flexible systems, independent gas distributors can justify premium pricing when meeting the demands of customers whose requirements are dynamic and often urgent. When customer requirements become predictable, however, independent distributors sometimes find that they are at risk of losing accounts when the cost of raw materials, including gases, is subject to increased scrutiny. This situation reduces independent distributors’ margins.
Among the cylinder gases that distributors might fill themselves, hydrogen has been one of the last choices. Requiring more equipment and infrastructure than other gases such as oxygen, nitrogen, argon, helium, and carbon dioxide, and offering a smaller amenable market, hydrogen cylinders have traditionally been purchased from major gas producers and resold by independent distributors, rather than being filled at the distributor level. Buy and resell eases distributors’ filling challenge, but creates certain disadvantages. For example, buy and resell can limit a distributor’s product availability and flexibility, compress margins, and tie up vehicles and money. It also makes distributors vulnerable to competitors (sometimes their own suppliers) stealing their accounts.
Particularly for the supply of high purity grades of cylinder hydrogen, for purposes such as epitaxy, silicon furnaces, and gas chromatography, independent distributors have been at the mercy of the majors for their supply. If high purity grades of cylinder hydrogen could be filled by distributors themselves at reasonable cost, it would enhance their business and profitability. Proton OnSite™ (www.protononsite.com) has introduced a new model of Proton Membrane Electrolysis (PEM) hydrogen generator that can do just that. This system makes relatively small quantities of extremely high purity hydrogen at sufficient pressure to fill 2,400 psig hydrogen cylinders without requiring a hydrogen compressor. Proton’s HOGEN™ HP40 hydrogen generator offers distributors the chance to become self-reliant for most if not all of their hydrogen needs, and may offer them the opportunity to increase their margins.
As with other cylinder and bulk gases, the selling price of cylinder hydrogen is heavily dependent on the purity grade of the contained gas. Every “nine” of purity can double the selling price, or better, making high purity grades of hydrogen more attractive than industrial grade product from a profit perspective. But accessing very high purity grades of hydrogen is difficult.
For example, accessing hydrogen via tube trailer and maintaining very high purity in cascade filling from the tube trailer requires strict procedures and care. Also, because a hydrogen tube trailer may hold up to 125,000 standard cubic feet (scf) of hydrogen, the tube trailer itself becomes a storage problem under NFPA (National Fire Protection Association) flammability guidelines. Many distributors don’t have the room to hold a hydrogen tube trailer on their site in compliance with NFPA guidelines.
Alternatively, major independent distributors can buy liquid hydrogen to fill cylinders and tube trailers, but liquid hydrogen only is available from major industrial gas producers and is widely available only in North America. The liquid hydrogen pumping approach introduces several additional issues including very high front-end and monthly costs and the problem of liquid hydrogen vaporizing and venting if the distributor doesn’t pump cylinders every day. As with filling cylinders from a tube trailer, filling hydrogen cylinders from a liquid hydrogen source must follow NFPA spacing and fill procedure requirements.
Designed for a 100 percent duty cycle, Proton’s HOGEN HP40 hydrogen generator will produce up to 40 scf/hr of 99.9995+ percent purity electrolytic hydrogen at 2,500 psig, without a compressor to buy or maintain. The hydrogen purity can be increased to 99.9999 percent with a simple, inexpensive desiccant drier, which is available from Proton or others. The HOGEN HP40 hydrogen generator produces enough hydrogen to fill 28 cylinders per week of electronics grade hydrogen at 99.9999 percent. Any impurities in PEM electrolytic hydrogen are limited to those actually present in the water used to make the hydrogen, which also can cross the impermeable Nafion membrane; these impurities are known and limited. A HOGEN HP40 hydrogen generator equipped with downstream desiccant dryer produces hydrogen of 99.9999 percent assay, with known sub-1 ppm levels of water, nitrogen, and oxygen. As the HOGEN HP40 contains less than 10 scf of gas at any time, it can be utilized on a distributor’s site without the NFPA spacing concerns of a tube trailer or liquid hydrogen tank cylinder fill system.
With a much simpler and lower cost installation than a liquid hydrogen pumping system, and lower variable costs per volume of hydrogen gas filled than a tube trailer cascade system, the HOGEN HP40 hydrogen generator may provide up to electronic-grade hydrogen cylinders, at a total fixed plus variable cost, which is lower than fill alternatives. As compared to buying and reselling hydrogen cylinders, the business advantages are considerable. The HOGEN HP40 hydrogen generator may allow independent industrial gas distributors to grow their business and ensure their independence. |
