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Finding a supplier for a difficult order

Q: I have several chemical manufacturing sites have a need for a compressor requiring the following specifications. The molecular weight of the gas is 18.0 and is saturated H2O vapor with trace (50 ppm) concentration of hydrogen peroxide. Flow rate = 11,562 kg / hr Inlet temperature = 47oC Inlet pressure = 80 mm Hg absolute Relative humidity = 100% Discharge pressure = 456 mm Hg absolute Cooling water temperature = 30 oC Ultimately, we will require three units. Unfortunately, I cannot find an interested supplier in the U.S. and a European colleague cannot find an interested supplier in Europe. How can I obtain these machines and if I find a supplier willing, how can I ensure high quality, timely delivery, and longterm reliability?

A:

If I did not misinterpret the data, I think I understand the difficulty in getting a bid for this application. Based on the data given I did a sizing of a compressor for this application. The problem is that this is a very high flow application, near the upper end of current beam type centrifugal compressors. A gear mounted multistage centrifugal could cover the flow. The flow could be handled by an axial. However this brings up a second problem, which is the required head to meet the specified pressure ratio.

This laterproblem could be solved by putting several compressors in series, which would require at least two for either the beam type or the gear mounted compressors. In the gear mounted compressor the head can be reduced by interstage cooling as each impeller can be cooled, but this would be limited in this case due to the onset of condensing if too much cooling is used. The axial could be put in series with a beam type centrifugal compressor to achieve the head. My guess, since this would be such a very large compressor train, which I think is unique and would be very expensive that the suppliers are not taking this too serious.

Should you find a supplier, and to answer your other question, relative to reliability, you would not have the option of checking with other users who have this type of compressor train  which is normally recommended. For the specifications, I would recommend you use API 617 "Axial and Centrifugal Compressors and Expander-compressors for Petroleum, Chemical and Gas Industry" which is based on custom engineered compressors and is geared to obtaining reliable compressors.

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