Cast Zirconium Pump the Answer to Rohm and Haas Corrosion Problem

Oremet-Wah Chang recently produced this 2745-lb. pump casing for a Rohm and Haas sulfuric acid application.In July of 1997, Goulds Pumps of Seneca Falls, New York contacted Oremet's Casting Sales and Marketing Group with a big request. Goulds' customer, a Rohm and Haas plant in Deer Park Texas, was having severe corrosion problems with some of its processing equipment and concluded that Zirconium 702 just might be the solution. Goulds asked Oremet to quote on what would be the largest zirconium pump body ever cast - a part estimated to tip the scales at 2500-lb. In addition, Goulds asked if the casting team could produce the cover, suction side plate, and impeller for the pump.

Rohm and Haas requested that Goulds Pumps produce the circulator pump. The chemical company was experiencing a serious problem in which Hastelloy® pumps were corroding sooner than expected in hot mid-range sulfuric acid. Rohm and Haas decided to explore the possibility of Goulds providing a long-term solution --zirconium-- to try and stop the corrosion problems that bedeviled its equipment.

Choosing a materials supplier was easy. Although no one had ever manufactured such a large zirconium pump before, Goulds had worked with castings expert Oremet to produce what was, at the time, the world's largest cast zirconium part (a 2100-lb. unit also built for Rohm and Haas in 1992).

An Oremet-Goulds team traveled to Rohm and Haas, examined the pumps, and agreed that one of the three Hastelloy@ pumps in service had very serious corrosion problems that warranted replacement. In-service coupon tests and literature studies confirmed that zirconium would solve the problem.

The next hurdle involved the size of the pump. The 2500-lb. zirconium casing that Rohm and Haas required actually exceeded Oremet's dimensional limitations for castings. Oremet determined that it would have to cast the part in three sections, then weld it together.

Since this would be the largest zirconium pump casing ever poured, Goulds and Rohm and Haas also had quality concerns and requested source inspection of the parts. Oremet passed the inspections with flying colors and was given approval to finish welding without additional source inspection.

Oremet produced the zirconium casing much like any other casting made in its Albany, Oregon plant. The company designed and built pattern equipment. It then produced molds by packing graphite and binder (ramming) around the patterns.

After forming, the molds were fired. The finished molds were set up and sent to melting. Zirconium was melted and poured into the molds under vacuum.

After cooling, the parts were knocked out of the molds. Following various cleaning and grinding steps, the parts were hipped and welded into one casing.

Timely delivery was critical since Rohm and Haas estimated that the Hastelloy unit would only be able to work another few months before it had to be shut down due to severe corrosion problems. And, if the process line had to be shut down, it would cost the chemical company millions of dollars in lost production.

In May 1998, the company met its deadline and all of the dimensional criteria (as if the casing were a one piece casting) and shipped the ordered components to Goulds on time. The materials were received at Goulds Pumps, and the manufacturer was able to machine the large casing and components without a problem. Goulds assembled the pump and sent it via a special flatbed truck to Deer Park, Texas for installation at Rohm and Haas.

When all was said and done, the 72-in. high casing actually weighed in at a hefty 2745 lbs. In a matter of months, Oremet-Wah Chang and Goulds took on a big corrosion problem and remedied it with a solid solution...the world's largest cast zirconium pump.

For further information on corrosion resistant pumps, contact Goulds at 315-568-2811. For information about titanium and zirconium castings, phone Oremet-Wah Chang at 541-812-7055 or fax requests to 541-812-7446.

JNFL Specifies Zr-702 for Spent Fuel Reprocessing Facility

JNFL began constructing a reprocessing plant in Rokkasho-mura, Aomori, Japan in April of 1994. This will be the first large commercial-scale reprocessing plant in Japan. The facility for storage of spent nuclear fuel is nearly complete, and all facilities are scheduled to be completed around 2003, when reprocessing is to be started.

The capacity of the reprocessing plant is 800 MTU/year, which is equivalent to the quantity of spent nuclear fuel generated from around thirty 1,000 MW-class nuclear reactors annually.

The total construction cost is estimated to amount to approx. 1,880 billion yen ($13 billion).

The purex process is applied at the facility. The process has been proven in separation and refining of uranium, plutonium and fission products in Japan and other countries. Additionally, the following state-of-the-art technologies are being employed at the facility.

= Technology for shearing/dissolution and separation/purification from SGN, France
= Technology for depressurizing/evaporation of liquid waste from BNFL, U.K.
= Technology for iodine removal for gaseous waste coming from shearing and dissolving processes from KEWA, Germany
= Technology for vitrification of high-level radioactive liquid waste and denitration of uranium and plutonium from PNC, Japan

Zirconium and stainless steel will be used for some process equipment and components. Zirconium, especially, will be used for the major parts, such as in the dissolver and the iodine desorber.

All zirconium products, including Zr-702 bar, piping and plate, required for this plant are manufactured by Oremet-Wah Chang and supplied to Japan through Oremet-Wah Chang agent, Mitsui & Co., Ltd.

To contact Mitsui & Co., call 81-3-3285-3356 or fax 81-3-3285-9985.11

Japan's first large commercial-scale spent fuel reprocessing facility, located in Rokkasho-mura, Aomori, will use zirconium in leading-edge process equipment.

Castings: A Growing List of Applications

The use of titanium and zirconium castings in corrosive applications, pollution control equipment, marine, petrochemical and other industries has increased significantly in recent years. And there's no doubt that the list will continue to expand as new uses are found for these amazingly versatile materials.

Both titanium and zirconium have proven unusually resistant to corrosive attack. These metals and their alloys are virtually immune to many oxidizing and reducing environments.

Oremet-Wah Chang casts titanium and zirconium for a variety of applications, including components for marine, chemical and mineral processing, pollution control, and other equipment.

Titanium and zirconium's exceptional resistance to corrosion is due primarily to their tenacious oxide films. When exposed to the atmosphere, these metals form tight, cohesive oxide surface layers which are resistant to a wide variety of corrosive media.

When to specify:

Since titanium is highly resistant to attack by oxidizing media, it is ideally suited for the following environments:

• wet chlorine gas

• hypochlorous acid

• nitric acid

• sea water and fresh water

• solutions containing chlorine

• hypochlorites

• calcium chloride

In these destructive environments, titanium may last many times longer than some common metals. So while the initial outlay is greater, titanium often proves very economical on a life-cost basis.

Zirconium. also a reactive metal performs best in reducing environments. Because zirconium is a very corrosion-resistant metal it will perform especially well in the following environments:

• hydrochloric acid

• sulfuric acid

• caustics

• phosphoric acid

• nitric acid

• organics and organic acids

Since most corrosive environments are not covered by simple cases, testing is recommended Oremet-Wah Chang maintains a complete test laboratory to assist customers in corrosion testing and material selection.

Current cast product applications:

• Pollution control

• Valve sets

• Impellers

• Marine Hardware

• Hydrofoil components

• Special Purpose Equipment

• Anodes

• Agitators and Mixers

• Logging Equipment

• Pump sets

• Oceanographic Instrument Housings

• Seaballs (for oceangoing submarine valves)

Oremet-Wah Chang castings available:

Titanium, zirconium and their alloys as centifugal, centifuged, or static castings depending upon shape and size

Dimensional tolerances:*

Minimum section thickness 3/16 inch; 1/8 inch if less than 1 square inch of surface

Base tolerances:*

• Up to one linear inch + 1/32 inch
• 1 inch up to 10 inches + 1/16 inch
• 10 inches up to 20 inches + 1/8 inch
• 20 inches up to 60 inches + 3/16 inch

Added tolerance for dimensions across the parting line: + 1/8 inch
Added tolerance for dimensions affected by parting line and parallel to the parting line (mis-match):

• + 1/16 inch less than 10 inch
• + 1/8 inch 10 inch and above

Radius dimensions:*

• Sharp to 1/8 inch radius + 1/32 inch
• 1/2 inch fillet radius + 1/32 inch

Finish stock:*

Nominal 1/8 inch on all machined surfaces for dimensions less than 12 inch; nominal 3/16-1/4 inch on all machined surfaces greater than 12 inch.

Maximum weights:

Oremet-Wah Chang castings are produced over a weight range of 1 lb. to 1800 lbs. (0.5 kg to 818 kg)** in titanium. Zirconium castings can be produced in any size up to 2400 lbs. (1090 kg)**. Larger castings can be produced by fabricating several castings into a single component.

*Stated tolerances represent historical performance. Size and configuration of your part may enhance capability. Contact the Oremet-Wah Chang Casting Team for dimensional analysis of your job.

**In certain configurations, castings weights in excess of this figure are possible but must be evaluated on a case-by-case basis.

Pattern equipment:

Standard loose or match-plate patterns, either wood or metal. Standard core boxes except those designed for core blowing only. Customers may provide equipment subject to process acceptability. Most ferrous and nickel based alloys conform dimensionally. Pattern modifications or new construction can be accommodated through a local state-of-the-art pattern shop. Generally pattern equipment designed for sand casting processes can be utilized with modifications to gating and risering systems.

For more information on corrosion resistant casting products, contact Oremet-Wah Chang at 541-812-7055 or fax questions to 541-812-7446.11

Q&A:

Question: DO titanium and zirconium exhibit similar corrosion properties?

ANSWER:

Similarities do exist. For example, zirconium and titanium are excellent for handling seawater, where more common metals are unsuitable. However, zirconium and titanium exhibit some significant differences in corrosion properties. Both metals are counted on heavily for use in severe environments (see accompanying table), but mistakes can be made when their dissimilarities are overlooked.

The excellent corrosion resistance of zirconium and titanium are attributable to the formation of an autogenous, adherent and stable oxide film on the metals' surfaces. Zirconium's predominately quadri-valent oxide is inherently more protective than titanium's multi-valent oxides. Consequently, the differences between zirconium oxides and titanium oxides are responsible for the corrosion differences.

Zirconium is attractive for reducing acids like H₂SO₄ (<70%) and H₃PO₄ (<55%). Zirconium is also suitable for handling other reducing acids, such as sulfurous and sulfamic acids. Titanium has limited usefulness in pure reducing acids, it is adequate for up to ~5% H₂SO₄ and ~30% H₃PO₄ at room temperature.

Titanium is well known for its excellence in oxidizing acid solutions, such as FeCl₃, CuCl₂, and aqua regia. It is likely the most practical material for handling hot, oxidizing acid chloride solutions. The presence of oxidizing ions helps titanium form a protective TiO₂ film. Zirconium does not fair well in chloride solutions. It is susceptible to localized corrosion under oxidizing conditions. Zirconium can be used to handle oxidizing chloride solutions when measures are taken (such as application of a small cathodic polarization).

In non-acidic chloride solutions, such as seawater, NaCl, KCl, and SnCl₄, both zirconium and titanium are corrosion resistant over a wide range of conditions.

Zirconium resists attack in most alkalies. It is one of the few materials that has corrosion resistance in solutions ranging from very acidic to alkaline. Zirconium has been used for processes that cycle between strong acids and strong alkalies. Titanium resists attack in weak alkalies, but not strong alkalies. A major concern for titanium in alkaline solutions is hydrogen embrittlement. Corrosion resistance of titanium in alkaline solutions can be improved by adding strong oxidizers, such as chlorate and hypochlorite compounds.

Zirconium has a low affinity for chlorine at temperatures below 200°C. It resists attack by dry chlorine but is susceptible to localized corrosion in wet chlorine. Titanium has a high affinity for chlorine, even at low temperatures.

Ignition of titanium in dry chlorine (<0.5% H₂O) is possible. In wet chlorine (<0.7% H₂O), titanium reacts easily with H₂O to form a protective TiO₂ film and is one of the best metals for handling the chemical.

Zirconium is much more reliable than titanium for processing organic compounds, such as acetic, formic, and citric acids. Zirconium has resistance in almost the whole concentration range of these acids to elevated temperatures.

Conclusion

Zirconium and titanium can be corrosion resistant or reactive depending on the nature of the environment. They often exhibit quite different corrosion resistance under many conditions. It is important to recognize these differences in order to use these materials for severe environment applications.

For more information on the corrosion resistance of zirconium and titanium, contact Oremet-Wah Chang’s Corrosion Lab at 514-917-6777.

This issues Question and Answer was adapted from work submitted by corrosion consultant, Dr. Te-Lin Yau. Dr, Yau, who headed Wah Chang’s corrosion research effort for many years, has published numerous articles on the corrosion resistance of materials, including several in Outlook.

First International Conference on Reactive Metals in Corrosive Applications

CALL FOR PAPERS

Oremet-Wah Chang is pleased to announce an international conference on "Reactive Metals in Corrosive Applications", September 12-16, 1999, in Sunriver, Oregon. This conference follows the successful Zirconium /Organics Conference held in September 1997 that covered topics ranging from zirconium in organic media to various aspects of designing and fabricating zirconium equipment. The attendance enjoyed international participation from end-users, fabricators, equipment manufacturers, engineering contractors, and academia. The focus of the 1999 conference is expanding to include the reactive metals zirconium, titanium, niobium, and tantalum.

We invite you to participate in the conference by submitting a paper for presentation. We are looking for presentations that discuss the application of zirconium, titanium, niobium, or tantalum in chemical process environments. Potential topics and areas of interest include:

Industrial Applications

• Specific Organic Environments
• Specific Mineral Acid Environments
• Food Processing
• Pulp and Paper
• Fertilizers
• Hydrometallurgy
• Pharmaceuticals
• Electronics, including ultra-pure chemicals
• Petroleum production

Science and Technology

• Corrosion Mechanisms
• Oxide Film Characterization
• Metallurgical Properties
• Alloy Development

Fabrication

• Equipment Design
• Surface Treatments
• Manufacturing Trends
• Standards and Specification
• Cladding Technologies

Service History

• Case Histories
• Failure Mechanisms
• Life Cycle Cost Analysis
• Material Comparisons
• Applications Development
• Project Management

Interested authors should submit a 250-350 word abstract with the title, author(s), and the attached form by October 30, 1998 to Oremet-Wah Chang. The abstract may be accompanied by charts, graphs, or tables. Authors of the selected papers will be notified by December 4, 1998. Final manuscripts will be due to Oremet-Wah Chang no later than May 7, 1999. All selected papers that are submitted within the deadlines will be included in the conference proceedings. Contact Mr. Jack Tosdale at 541-917-6777 if you have a topic you would like to discuss. Finished abstracts should be sent to Mr. Tosdale at Oremet-Wah Chang, P.O. Box 460, Albany, OR 97321 or faxed to 541-967-6987.

Organics Proceedings Available

Oremet-Wah Chang has a limited number of copies of the Conference Proceedings for the 1997 International Zirconium in Organic Acid Environments Meeting. The Proceedings contain 23 papers, including useful technical information from chemical producers, chemical plant equipment fabricators, and metals producers. Companies who sent representatives to the conference can purchase extra copies for $50. Non-attendees may buy a copy for $495 (the price of conference admission). Contact Oremet-Wah Chang at 541-926-4211 ext: 6280 for more information or to place an order.

Ammonium Nitrate Producers Study Group

Coastal Chem, Inc. will host the 1998 Ammonium Nitrate Producers Study Group (ANPSG) Meeting at the Snow King Resort in Jackson, Wyoming, October 5-8. Oremet-Wah Chang and a contingent of suppliers to the chemical process industries will be on hand to co-host a golf scramble and awards reception (October 5), a luncheon (October 6), and evening hospitality events (October 6 and 7). Most importantly, the exhibitor group will offer solutions to challenges facing plant operators and engineers.

For more information about the meeting (including registration), call Coastal Chem's Trish Becklinger at 307-637-2730. For further information on the exhibitor and hospitality programs, contact Wah Chang's Kirk Richardson at 541-967-6955 or Sheryl Renzoni at 541-926-4211 ext: 6280. (Note: space is limited, so sign up soon!)

We look forward to seeing you in the Wild West this fall!

ITA Applications Conference

The International Titanium Association (ITA) will host its 14th Annual Applications Conference and Exhibition October 4-8 at the Hotel Loews Monte Carlo in Monaco. This year's conference, the first to be held outside of North America, promises to be the most unique ever. In addition to top level speakers in the forefront of the industry, the conference will offer high-tech workshops and panel discussions on such subjects as new technologies in titanium manufacturing, chemical processing applications, welding, surface treatment, titanium in future aircraft, and much more.

The High Performance Metals Group of Allegheny Teledyne will be in Monte Carlo to showcase its new combination of manufacturing capabilities and metal products. Now one of the top three titanium producers in the world, HPMG, through its Allvac, Allvac SMP, international Hearth Melting, Oremet-Wah Chang, Rome Metals, and Titanium Industries operating companies, can draw on an extensive network of titanium melting, finishing, and distribution facilities and equipment to meet almost any customer need.

To celebrate this new force in titanium, HPMG will be hosting a special reception before the ITA banquet at the spectacular Monte Carlo Sporting Club. For more information on our conference events, look for our special Titanium Edition of Outlook in September 1998! For more information on the conference, contact the ITA at 303-443-7515. •

Nitric Acid Producers Meeting Recap

Oremet-Wah Chang recently joined 37 co-exhibitors in hosting luncheons and hospitality events at the 1998 Nitric Acid Producers Meeting in beautiful Jasper, Alberta, Canada. Approximately 250 people gathered to discuss challenges facing nitric acid producers and potential solutions. Many answers were provided by the exhibitors, who offered everything from metals and other materials to fabrication to engineering services. Feedback from the producers has been very positive.

Oremet-Wah Chang thanks producer and meeting host Agrium for its great efforts in making the event a success.

This year's Exhibition Hall Master of Ceremonies, Bob Gill of Ellett Industries (Vancouver, B.C.), thanks his bodyguard for saving him from the hostile crowd. "Truth be told", the Royal Canadian Mounted Policeman graciously dropped by to mix with Nitric Acid Meeting attendees and exhibitors and pose for a few photos.

We also thank our exhibition hall co-hosts Allegheny Ludlum, Alloy Engineering, AstroCosmos, BSL, C&I Engineering, Chemineer, CRI Catalyst Company, Degussa, Dollinger, Doyle & Roth, Dynamic Materials, Ellett Industries, Engelhard CLAL, H.A. Simons, H.C. Starck, Haynes, Hickham Industries, High Performance Tube, industrial Alloy Fabricators, ICF Kaiser, Ionics RCC, Johnson Matthey, Joseph Oat, Koch Engineering, KTI Fish, Kvaerner Chemetics, Nooter, Ohmstede, PGP Industries, Phoenix, Sabin Metal, SPF America, Stockhausen, Tricor, W. L. Gore, and Weatherly. Your participation in the exhibit hall and events helped make the 1998 Nitric Acid Producers Meeting a great success? We look forward to seeing you at next year's meeting in Nashville, Tennessee.•

Sulphur '98 Meeting

British Sulphur is hosting Sulphur '98 November 1-4 at the Westin La Paloma in Tucson, Arizona. Visit Oremet-Wah Chang at stand #7 to learn about the latest metals solutions to sulfuric acid corrosion challenges. For more information on attending or exhibiting at the conference, contact British Sulphur's Tina Fiman at 44 171 903 2437.11

ANPSG Meeting Winner Update

Darrell Larsen (ICI) and wife Connie, winners of the exhibit hall raffle at the 1997 ANPSG Meeting, enjoyed their good fortune on a cruise to St. Barths, St. Kitts, St. Martins, Nevis, and Antigua islands. Darrell and Connie thank all of the exhibitors for an unforgettable time.