\"Handbook of Chemical Process Design\": Power calculation for isothermal compression of compressors

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Everyone, take a look at the issue with the calculation formula and discuss it. I wonder if there are any corrections; if corrections have already been made, please ignore this issue. “Handbook of Chemical Process Design”, 5th edition, Page 1261, Chapter 28: Compression and Expansion Machinery 1. Thermodynamic Calculations for Ideal Gases 1.1 Isothermal Compression During isothermal compression, the temperature remains constant; at this time, p1V1 = p2V2 = constant. The power required during isothermal compression is the lowest. The theoretical power required in this case is given by N = 1.634 × 9.81 × p1V1 × ln(ε). Here, N represents power in kW; p1 and p2 are the pressures of the gas when it is drawn in and discharged, in absolute terms, in Pa; V1 and V2 are the volume flows of the gas at the inlet and outlet states, in m3/min; ε is the compression ratio, defined as ε = p2/p1. However, the formula for calculating power given above is incorrect. The correct formula should be N = 1.667 × 10^-5 × p1V1 × ln(ε) in kW. The values of p1 and p2 remain the same as before, while V1 and V2 as well as ε are defined similarly. The value 1.634 in the above formula comes from page 18 of “Process Design Data for Refining Equipment (Compressor Process Calculations)”. In that book, 1.634 is calculated as (9.8 × 10)/60, and this formula is correct.