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What you want to know....fast.

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: May 15, 2007

News
Technically Speaking

North America

Sale
Arkema will sell its specialty amines business based in Riverview, Michigan to Taminco.  The business is part of Arkema’s thiochemical division and has annual sales of about $72 million.  The specialty chemicals include alkyl-alcanol-amines (AAA), alkyl-hydroxyl-amines (DEHA) and basic alkyl-amines (AA).
Purchase
Canada-based Chemtrade Logistics has bough the liquid sodium hydrosulphite business of U.S.-based Olin for $7.3 million.  The deal did not include Olin’s liquid SHS manufacturing assets.  Olin will continue to make the product for Chemtrade.
Unit Closure
Dow’s number 8 Freeport cracker in Texas was shut down short-term following a fire in a naphtha pump.  The fire also impacted the number 7 olefins unit, but only briefly.  No injuries were reported.
Investment
The Department of Energy will spend $200 million over five years to fund up to 10 cellulosic research biorefineries for ethanol and bio-based chemicals.  The program is intended to jump-start cellulosic research and the department is seeking research applicants who can share funding on a 50-50 basis toward successful demonstration of cellulosic biorefineries at one-tenth of commercial scale.  Small-scale projects are being targeted to help discover and develop a variety of cellulosic feedstocks, new approaches and refining processes.  The small-scale projects are expected to be operational within four years and will speed the adoption of new technologies to produce ethanol and bio-based chemicals from cellulosic feedstocks, with commercial-scale demonstrations to follow.
Expansion
Potash Corporation of Saskatchewan, Canada has started a $775 million project to expand potash production by 1.2 million tons/year at its Cory operation.  Included in the investment is $75 million for 750,000 tons of new compaction capacity.  The project involves de-bottlenecking underground operations as well as significantly expanding the production of red potash products.  A new plant will be built for the crushing, flotation, centrifuging and drying of 2 million tons/year of red products, with up to 800,000 tons to be crystallized for white product production.  In addition, storage, load-out and rail yard capabilities will be expanded.  Work has begun and is expected to take 36 months to complete.
Refinery Emissions Cut
The Environmental Protection Agency (EPA) is seeking to impose emissions restrictions on new, modified or rebuilt process units at petroleum refineries.  Under the proposed change, refiners would be required to add state-of-the-art emissions control equipment on new or updated facilities as well as require changes in certain work practices.  While this may cost the industry $55 million annually, it could provide environmental benefits of up to $950 million annually.  The implementation period would be five years, but is intended to result in reduction of combined emissions of particulates, sulfur dioxide and nitrogen oxide emissions by nearly 56,000 tons/year.  The standards would include emission limits for fluid catalytic crackers, fluid cooking units, delayed cooking units, process heaters and other fuel gas combustion devices or sulfur recovery plants.  It would also require refiners to generate and implement plans aimed at minimizing emissions from refinery start-ups and shutdowns.
Push for Ethanol
Mexico’s Chamber of Deputies has passed a bill to promote the use of ethanol as an oxygenator instead of methyl tertiary butyl ether (MTBE) in gasoline and to increase the use of biofuels.  The bill gives the task of developing policy on biofuels to the Inter-Ministerial Rural Development Commission, asking it to focus on the use of sugar cane and maize for ethanol, oil-producing plants for biodiesel, and on promoting products that increase air quality.
Onshore Facility
Ambar Lone Star Fluid Services (ALSFS) has opened a 21,800-square-foot distribution and operations complex in Tyler, Texas.  ALSFS is a subsidiary of Patterson-UTI Energy, Inc. and offers a complete line of drilling and completion fluids, including the patent-pending DFX high performance water base mud or Eco-Syn synthetic fluid for deepwater environments.  The new facility was built to expand and enhance both technical and service capabilities for customers in Arkansas, Louisiana and Texas.  The complex consists of a 10,000-square-foot warehouse and a 4,000 square-foot warehouse for drilling/completion fluids material storage and a 7,800-square-foot office facility, housing operations, distribution, sales and a fluid testing laboratory.  The distribution yard has storage capabilities for 25,000 sacks of bulk barite material.

World

Auto Coatings
Rohm and Haas will sell its European automotive coatings business to Mader Group for an undisclosed sum.  This is the last phase of Rohm and Haas’ global automotive coatings divestiture.

Divestiture
Danisco has entered into an agreement to divest its flavors line to Firmenich for $611 million, roughly 2.2 times annual sales revenue.  The deal is expected to close in June and will be accomopanied by a strategic partnership agreement aimed at providing unique and comprehensive solutions for the food industry by the two companies.
Oil and Gas Find
Kuwait believes it has discovered a large oil field in the north of the country, along with gas.  The find is touted as having the ability to have a positive impact on the country’s oil and gas strategy.
Presence Expanded
GE Oil & Gas has established a new Field Service and Maintenance Center for Trinidad and Tobago.  A 30,000 square-foot facility is located in Point Fortin, Trinidad, adjacent to the Atlantic LNG Company’s production facility.
Training Center
Halliburton has opened a new training center in Tyumen, Russia, in cooperation with Tyumen State Oil and Gas University.  The center is intended to further develop the professional and technical skills of the company’s employees in the Europe Eurasia Region.  It is equipped with three classrooms, a laboratory, and state-of-the-art videoconferencing equipment that gives the students real-time access to other students and technical experts around the world.


Technically Speaking

How do I do the preliminary sizing of a surge drum in a closed loop liquid system?

"By the very definition of 'Surge Drum', it is a vessel that is designed to provide a given volume or residence time for the fluid passing through. I have only heard the term used in connection with liquid services, so I'll address it from that point of view. I suppose the term could also be applied to gases, however.

To size a surge drum, you must know the flowrates of materials into and out of the vessel. Typically, the vast majority, if not all of the flow, would be liquid. You must develop a sizing criteria. Perhaps something such as providing for a (say) 5 minute interruption of flow to the downstream unit. So, if your Surge Drum is at its normal operating level and you must interrupt outflow for 5 minutes, you'd like to do so without impacting the upstream unit. That would be typical of the thinking that might occur during the design process.

You next decide on an acceptable minimum, normal, and maximum operating level for the vessel. The minimum might be due to a pump requirement, for example. The maximum could be to avoid overfilling the drum. Now take your design flowrate (let's call it 2 cubic meters per minute), multiply by the 5 minutes of surge you want to provide, and you have the surge volume. That volume must be contained between the normal and the maximum drum levels. Estimate the total volume needed by estimating the normal and maximum levels in this case, and then calculating the total vessel volume.

So you have a flowrate of 2 m3/minute into the drum and you want to run it at least 1 meter full to provide the needed pump NPSH. You also want to leave 250 mm of vapor space at the top for your blanketing gas. You have a surge volume of 2 * 5 = 10 m3. A vertical cylinder of dimensions 1.62 m diameter x 4.86 m high would provide a total volume of 10 m3. Add 1 m of unused space at the bottom and 0.25 m of unused space at the top, and you have a surge drum. Its dimensions would be 1.62 m diameter x (4.86+1+0.25=) 6.11 m high.

Though this seems like a simple problem, it can actually get quite a bit more complex. First note the dimensions chosen. The original 1.62 m diameter x 4.86 m high was chosen to have an length/diameter (usually called L/D) ratio of 3. Using a range of 3 to 5 for the L/D ratio generally gives an economical choice. I chose 3 because I knew the final ratio would be higher as I added in low and high level allowances. For pressure vessels, move closer to 5 at higher pressures, and closer to 3 at lower pressures. (Note that this does NOT apply to atmospheric tanks.) If we use a horizontal vessel, which is more typical, then the calculation of the useful or surge volume is substantially more difficult. In this case, you'd need to assume dimensions, calculate the unusable volume at the top and bottom of the drum, and then determine how much useful volume is left. By hand, this would be a trial and error calculation. The situation worsens further as you consider that the drum almost surely will not have flat heads; it will have elliptical or perhaps hemispherical heads. Calculating the volumes of partially filled heads adds to the complexity of the overall procedure. Fortunately we have spreadsheets and other tools which make this job relatively easy."

djack77494 via Cheresources.com Forums

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