Gas Moving Pressure Service

Fans Power up to 7.5 kW/m /s. For fan air-conditioning package units 13.5 Ndm /s per ref of floor area. For the process area, allow 13.5 Ndm /s per kW for refrigeration for office space, X 3 for stores, X 7. Allow 0.5 L/s of cooling water/kW of refrigeration. Related topic Section 3.12, refrigeration. 

Blowers, rotary lobe maximum pressure ratio 2 1. 

Rules of Thumb in Engineering Practice. Donald R. Woods Copyright 2007 WILEY-VCH Verkg GmbH Co. KGaA, Weinheim ISBN 978-3-527-31220-7 

Heat capacity ratio, k = Cp/c, = 1.04 for gases with molar mass 100. The value of k increases to 1.67 as the molar mass decreases. For air =1.4 and for such gases as ethylene, carbon dioxide, steam, sulfur dioxide, methane, ammonia = 1.2-1.3. Temperature rise between feed 1 and exit 2  

For each stage keep the exit temperature (T2-298) 120-150 °C. For diatomic gases, k = 1.4, this limits compression ratio P2/P1) to 4 for triatomic gases, 6. 

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In this section, we consider gas moving equipment for pressure service and then for vacuum liquid moving equipment. Then, two-phase flow is considered in Section 16.11.2.4. Hydraulic conveying of solids is discussed in Section 16.11.2.5. Conveying solids is considered in Section 16.11.2.6, while Sections 16.11.2.7 and 16.11.2.8 address piping and steam. 

Cylinders containing liquefied fuel gas should be stored or transported in a position so that the safety relief device is always in direct contact with the vapor space in the cylinder. All valves must be closed off before a cylinder is moved, when the cylinder is empty, and at the completion of each job. Low-pressure fuel-gas cylinders should be checked periodically for corrosion, general distortion, cracks, or any other defect that might indicate a weakness or render it unfit for service. 

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