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ChExpress

What you want to know....fast.


Dateline: February 7, 2006

News
Technically Speaking

USA

Production resumed
Terra Industries Inc. has resumed production of ammonia and upgraded products at its Woodward, Oklahoma facility.  Production had been suspended in November 2005 due to mechanical repairs and catalyst changes.

Manufacturing resumed
DuPont has resumed manufacturing operations at its Delisle, Mississippi titanium dioxide plant.  The plant had suffered a direct hit from Hurricane Katrina.  DuPont has completed considerable work to repair significant damages in order to restore operations in less than five months.  Work will continue round-the-clock to get the facility back up to the standards of its other titanium dioxide plants.

Expansion
Lonza plans to expand its mid-scale capacity at its biologics facility in Portsmouth, New Hampshire to fulfill the potential of its robust project pipeline.  The expansion will involve a number of 5,000-liter bioreactors.  Groundbreaking is planned for April.  This expansion follows the installation of a fourth 20,000-liter bioreactor at this facility, which will become operational in mid 2006.

New specialty alkanolamines facility
Dow Chemical Company has begun construction of its new specialty alkanolamines facility in Plaquemine, Louisiana.  The unit will produce isopropanolamines and alkyl alkanolamines used in gask treating and many other consumer and industrial applications.  The facility should be running sometime during the first-half of 2007.  The plant will have extensive product-mix flexibility allowing it to meet changing market needs while at the same time reducing levels of co-products and by-products that are common in today's operations.

New PVC facility
Formosa will build a 180,000 tons/year polyvinyl chloride plant in Texas through an investment of $1.1 billion.  The investment will include a 300 mega-watt power plant at the same site.

India

Joint venture
Solvay Group and Chemical Products Corp. (CPC) have launched the joint company of Solvay & CPC Barium Strontium GmbH & Co. KG.  The new company will provide worldwide management of the partners' barium carbonate and strontium carbonate technical grades, sodium sulfide, sodium hydrosulfide and strontium nitrate businesses.  The new company is headquartered in Hanover, Germany and is held 75% by Solvay and 25% by CPC.  The main production sites for the joint venture are in Germany (Bad Hoenningen), Mexico (Monterrey and Reynosa), India (Sri Kalahasti) and Korea (Onsan).

Polypropylene added to project
Reliance Industries Ltd. (RIL) has set up a new subsidiary, Reliance Petroleum Ltd. (RPL), to implement a refinery and polypropylene (PP) project.  This export-oriented refinery and PP complex will cost approximately $6 billion and is planned in a special economic zone at Jamnagar, Gujarat, adjacent to RIL's existing refinery and petrochemical facilities.  The complex should be completed by March 2008, with Bechtel as the engineering, procurement, construction and management contractor.  

Expansion planned
MCC PTD India Corp Pvt Ltd (MCPI), the Indian subsidiary of Japan's Mitsubishi Chemical Corporation (MCC), plans to expand at Haldia through an investment of $370 million.  A second production line with a capacity of 800,000 tons/year would be set up for producing purified terephthalic acid (PTA).  The current production capacity at the plant is 470,000 tons/year of PTA.  Construction work should begin in the middle of 2006 with mechanical completion scheduled for the end of June 2008. 

Technically Speaking

Are there are dangers posed in performing pressure testing with bottled gas or is another method preferred?

Mr. Art Montemayor addresses this question as follows:

"I do not recommend the use of pneumatic testing for piping or vessels within the confines of a process plant.  With over 40 years of engineering experience - 10 of them in the compressed gas industry - I regard pneumatic testing as too hazardous and risky.  That is my personal stand and it is based on personal field experience.  I insist on the use of Hydrostatic testing of equipment, rather than pneumatic.

Let me define the two testing methods:

Pneumatic testing is the use of a compressible gas (usually Nitrogen or air) to fill 100% of the volume to be tested and subsequently raising the gas pressure to the test level. 

Hydrostatic testing is where the internal volume to be tested is filled 100% with ambient temperature water and subsequently raising the water pressure to the test level. The means of raising the water pressure is usually done with a small, positive displacement piston pump but can be also done by imposing a compressed gas pressure (always through a 2-stage regulator).

I do not recommend usage of a compressed gas source as the pressure medium for application on a hydro test. Now, allow me to explain my recommendations. Often times, there could be no other pressure relief on the system besides the "bottle regulator".  The pressure within the gas cylinder could be many times higher than the test pressure.  Otherwise, you couldn't rely on it as a source of pressue.  This is also the source of the hazard!  Unless you have installed a pressure relief valve downstream of the gas cylinder, there is no safety for the system.  All industrial gas cylinders carry a rupture disc within the cylinder valve that is rated for protecting the cylinder - NOT YOUR PIPE OR DOWNSTREAM EQUIPMENT.

This cylinder safety device is installed for the case where the cylinder might be exposed to fire or excessive temperatures. 

It is relatively risky to test pneumatically because of the slowness of the system to relieve itself in the event of a failure.  A small crack will only emit the equivalent critical flowrate (reached at sonic -or "choked"-flow) and this is usually continued to be fed upstream at the pressure source.  This is the critical time when further addition of gas fluid will usually cause a massive failure of the equipment.  Gas regulators are simply that;  they are not pressure controllers nor can they be relied upon to react fast enough to mitigate a tragic accident.  This is particularly dangerous where there are cast iron component within the tested system.

Testing with water, on the other hand, will be characteristically much better controlled - especially if the pressure source is an independent, small and slow rpm piston pump.  Additionally, you can set the pressure relief valve on the pump's discharge slightly above the test pressure for additional safety.  You will discover that a test failure within the system will result in a spontaneous liquid leak and a similarly rapid decrease in system pressure.  As an added feature, you can easily trend the pressure maintenance within the system to confirm the success of the pressure tightness achieved in the system.  This is considered a much safer and conservative method by most experienced engineers.

Agreeably, there is a trade-off between both methods: While being considered safer, the hydrostatic test is slower and requires a source of clean water and subsequent drainage and dryout.  All of these items represent additional costs over the pneumatic test.  Nevertheless, I have always opted for the hydrostatic test because I sincerely believe there is no substitute for safety."

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