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christa.jpg (5628 bytes) Chemical Industry News Editor Christa Semko
Every two weeks, Christa will bring you the latest chemical industry news from around the world.  If you have a press release that you'd like to share with us, please mail it to us through our online contact form here.

Dateline: July 10, 2007

Technically Speaking

North America

Award Winner

Cargill was recognized in the 2007 Presidential Green Chemistry Challenge Awards in the U.S.  The Designing Greener Chemicals award was given for Cargillís BiOH polyols, the first commercially successful of its kind.



The New Jersey state government is seeking hundreds of millions of dollars worth of compensation from producers and distributors of methyl tertiary butyl ether (MTBE) and others for pollution damage.  New Jerseyís Department of Environmental Protection (DEP) has filed 120 lawsuits in various jurisdictions within the state against that many companies and more to cover cleanup costs and compensation for environmental damage that cannot be reversed.  Defendants include Amerada Hess, Atlantic Richfield, BP America, Chevron, ExxonMobil, Getty, Shell, Texaco and Valero Energy.  The suit is seeking recovery of all past and future costs to investigate, remediate and restore natural resources damaged by the discharge of MTBE.

Fat-Based Fuel

Tyson Foods and Syntroleum plan to make liquid synthetic fuels from animal fats for the diesel, jet and military fuel markets.  They will produce the fuels through technology developed by Syntroleum in facilities that will be constructed and operated by their 50/50 joint venture, Dynamic Fuels LLC.  Tyson will supply feedstock derived primarily from animal fats, including beef tallow, pork lard and chicken fat.  Vegetable oils and greases are also potential raw material sources.  Construction on the first plant will start next year at a yet-to-be-determined site in the south central United States.  The $150 million facility is expected to produce about 75 million gallons of synthetic fuel/year beginning in 2010.  The companies say that fat-based fuel will offer the same benefits as synthetic fuels derived from coal or natural gas while providing advantages over petroleum-based products, including higher cetane levels and lower emissions of carbon dioxide and nitrogen oxides.  The fuels will be usable in existing diesel engines with no modifications and should be compatible with existing pipelines and storage facilities.

Job Movement

Pfizer is moving 65 jobs from Sandwich, England to Kalamazoo, Michigan, where it is consolidating its global research and development for its Pfizer Animal Health division.  In addition, 300 jobs from an animal health research unit in Richland Township, Michigan will move to Kalamazoo.  The research farm in Richland will continue to operate.   


Polymer Deal
Arkema plans to buy specialty polymers and additives firm Coatex from
Switzerlandís Omva Group for an undisclosed amount.  The deal should close by the end of the third quarter.  The acquisition is part of the French companyís divestments of its non-strategic assets and ties to a new step in its growth plans.  The acquisition offers strong synergies downstream of Arkemaís acrylic monomer production in Bayport, Texas and Carling, France.  Coatex mainly makes acrylic-based polymers used as dispersants and thickeners for paper, paint, water treatment, cosmetics and textile industries.

Safety Charter

Dow Europe, INEOS Chlor and Chimcomplex Borzesti signed a product stewardship charter to ensure the safe use of trichloroethylene in metal cleaning applications.  The charter commits the signing companies to sell trichloroethylene to end-users with the appropriate equipment, minimizing workplace exposure.  The companies have also committed to phasing out the sale of trichloroethylene for open metal-cleaning systems by the end of 2010.  The charter was developed by the European Chlorinated Solvent Association.

Growth Plans

Xodus Group is planning growth for both its environmental and sub sea divisions.  The oil and gas engineering consulting group has recently added employees to these divisions and plans to add additional employees throughout the remainder of the year.  The additional employees are being added to help cover the number of new contracts the group has won this year.

Ethanol Venture

BP, Associated British Foods (ABF) and DuPont will build a $400 million plant in northeastern England to make ethanol from locally grown wheat beginning in late 2009.  BP and ABF will each hold a 45% share in the plant, with DuPont having the remaining 10%.  The facility will be built on BPís existing chemical site in Saltend, Hull and will have a capacity to produce about 100 million gallons of ethanol/year.  ABF will supply the wheat for the venture.  BP and DuPont will also build a technology research and demonstration facility at the site to produce the gasoline component biobutanol from feedstocks like wheat, corn, barley and rye.  The facility will initially produce ethanol, but the partners are looking at the feasibility of converting it entirely to biobutanol once the required technology is available.

Agreements Signed

BASF and Bosch will cooperate as members of a new German government-backed technology initiative aimed at making the manufacture of solar cells much more cost effective than it is today.  Germanyís federal ministry of education and research will provide about $80 million in research funding with companies like BASF, Bosch, Merck and Schott spending up to $400 million.  The partners are aiming to develop solar cells based on organic semi-conductive materials that can generate electricity from light at a lower cost than those with the silicon-based materials currently in use.  In conjunction with this goal, BASF and Bosch are each investing more than $2 million Heliatek, a company that specializes in the manufacture of organic solar cells.



Israel Chemicals will purchase Supresta from private equity firm Ripplewood Holdings for $352 million in cash.  Supresta manufactures elemental phosphorus-based flame retardants and other phosphorus-containing products.  The acquisition is expected to close later this summer and expands Israel Chemicalsí position in phosphorus chemicals and builds upon a previous acquisition.  Supresta will be integrated in Israel Chemicalsí industrial products portfolio to achieve both operational and raw material synergies.


Pfizer plans to spend $300 million on research and development in South Korea during the next five years.  The investment will support cooperation between Pfizer and the South Korean Ministry of Health & Welfare in the discovery and development of drugs through late-stage clinical trials.

Technically Speaking

I need advice on changing the duty of an API storage tank?  The service duty is changing and I have to decide on a new relieving set point.

"Low pressure storage tanks can be lethal and dangerous vessels – even in the pressure ranges of 0 to 15 psig and especially in the ranges of negative pressure (partial vacuum or 'external pressure').

If you’re revamping an existing API water tank to include a N2 blanket system or a fixed desiccant chamber in the breathing pipe, you find yourself in a dilemma because you need to fix the set points and “dead band” for the tank’s instrumentation and don’t know how to obtain these. My reaction to the situation is that one should never attempt to make any modification on a vessel – whether pressure or storage – unless the actual design calculations or specifications are in hand or if one can generate (or calculate) the required mechanical specifications that meet the proposed application.

As I’ve stated in the past, an API 650 or 620 storage tank is usually built to conform to operating pressures of 0 – 5 psig and partial vacuums down to 24 inches of water column (WC). I have found this range to be very appropriate and flexible for application to a very large variety of liquid chemicals – with or without N2 blanketing. HOWEVER, the ranges I’ve mentioned aren’t necessarily the ones that a specific tank was designed and built for. Tank fabricators will build an API tank to your purchase specifications and order. It has been my experience in inheriting existing field tanks in the past that most (if not all) tanks were purchase with nothing more than the description of “API storage tank”, period. No engineering specification or guidelines were given to the fabricator – especially a requirement to design to a specific MAWP (maximum allowable working pressure) or MAWV (maximum allowable working vacuum) – nor was the requirement for written design calculations and an API stamp noted. Naturally, the fabricator did exactly as the purchaser indicated (or did not indicate) and supplied just that: an API storage tank (probably one that was already partially built and “on the shelf” for immediate application. The sad result is what I and many others (like you) have had to confront out in the field, trying to make a sound, safe, and economic engineering decision.

Some years ago I decided I was not going to jeopardize my health and life as well as other people’s by taking the attitude of 'Just use a setpoint of ____ in W.C. They're all designed to withstand that.' I took a stand with what I thought was sound engineering and demanded that mechanical integrity be proven and documented in all tanks that I applied engineering on. I obtained what I thought was sound logic in the services of an experienced mechanical engineer with whom I worked hand-in-hand in making all vessel revamps. I learned a lot about what can and can’t be done with API storage tanks and the results speak for themselves: no 'suck-ins', stabile and safe operation, credible and reliable documented records, totally reduced emissions, minimal inert gas consumption, and quality product as well as raw material. I’ve done modifications such as umbrella roofs, anchor lugs, double-bottoms, wall re-enforcements, sloped floors, emissions controls, and many others. I would not attempt a revamp on a tank without a minimal of documentation and calculations that confirm the MAWP and MAWV of the vessel. That’s my comment, and I’ll add another directed to your specific first question: No, there is no 'minimum pressure, be it as low as a fraction of an inch of water', that one can believe a mechanically sound ‘atmospheric’ storage tank is capable of withstanding” - at least, not without proving it with checked, accurate, and documented calculations. That’s the very least that any owner can furnish you as an engineer working on their project. You deserve it, and you should have it coming to you. Fair is fair and you can’t compensate for past errors or omissions by taking steps that jeopardize your life and others. It isn’t morally (and now, finally) legally correct.

Paul Ostand has written a lengthy and, in my opinion, a very needed and useful paper on the employment of N2 blanketing. I dare not speak for such a qualified and experienced individual, but he does state the importance of storage tank mechanical integrity in his paper. Part I, under Methods and Requirements, states:

“When considering safety in relation to the gas blanketing system, bear in mind the following. The tank must be capable of operating at the desired pressure, with an appropriate factor of safety. The tank must be protected from vacuum and pressure that might occur outside of the operating pressure range and within safe limits of tank operation.”

So, even though Paul is not writing about API tank design and fabrication, he specifically identifies a pre-requisite for revamping a storage tank: make sure that your tank can withstand the pressures (or vacuums) you intend to impose on it before attempting any revamp.

Agreeably, our engineering logic and sound judgment is countered in the real-life applications where an owner expects his project engineer to correct a previous mistake or existing safety or environmental problem by simply “converting” a vessel to today’s state-of-the-art through the addition of new equipment on a rusted, non-stamped, undocumented piece of junk. I wouldn’t do it until it was proven that the subject vessel is, in fact, a reliable and mechanically sound piece of equipment with defined pressure ratings. I realize that it’s easy for me to assert my position strongly since I’m a consultant and my paycheck does not depend on any one individual liking me, my under-arm deodorant, or what I say. But nevertheless, I’m doing what’s correct by my engineering license and I can go home knowing that I haven’t harmed or damaged anyone with my decision. And no one can offer a reasonable, logical, and much less legal argument against my decision – at least not to my knowledge.

Thanks to all my prior relations and working with mechanical engineers, I can generate API tank design hand calculations. I have never used this ability to design a tank. I demand a design result from a recognized and experienced engineer. But being able to follow and understand the bases and underpinnings of tank design help out a Chemical Engineer enormously in later making mechanical or process modifications decisions. I highly recommend any Chemical Engineer to follow this principle whenever the opportunity presents itself. Learning and respecting what Mechanical Engineers can do is simply another way to broaden and diversify your capabilities as a professional engineer and dominating your craft.

Art Montemayor via Forums

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