Energy conversion factors Appendix

Table A 1.2 Energy Conversion Factors and Equivalents Appendix 1... 

Designers, manufacturers, and operators of boilers continue to use many of these terms, without undue deference to unit standardization, to define, measure, and report on plant steam-raising capacities power output) and operating parameters. (In continuance of this common practice therefore, many of these various terms are freely used in discussions throughout this book.) However, to familiarize the reader and minimize confusion, some energy terms and notes are provided here. A more complete list of units and conversion factors is provided in the appendix. 

For quantitative considerations it is convenient to use atomic units (a.u.), in which h = eo = me = 1 (me is the electronic mass) by definition. They are based on the electrostatic system of units so Coulomb s law for the potential of a point charge is = q/r. Conversion factors to SI units are given in Appendix B here we note that 1 a.u. of length is 0.529 A, and 1 a.u. of energy, also called a hartree, is 27.211 eV. Practically all publications on jellium use atomic units, since they avoid cluttering equations with constants, and simplify calculations. This more than compensates for the labor of changing back and forth between two systems of units. 

The advantage of the wavenumber scale is that it is linearly proportional to other energy units. Some of the relationships and conversion factors (see Appendix 8) are as follows ... 

Appendix A gives an extensive table of conversion factors for energy as well as for other units. 

Various units are used for expressing pressures (see Chapter 1, Footnote 8). A pressure of one standard atmosphere, or 0.1013 MPa, can support a column of mercury 760 mm high or a column of water 10.35 m high. As indicated in Chapter 1, the SI unit for pressure is the pascal (Pa), which is 1 N m-2 an SI quantity of convenient size for hydrostatic pressures in plants is often the MPa (1 MPa = 10 bar = 9.87 atm). (An extensive list of conversion factors for pressure units is given in Appendix II, which also includes values for related quantities such as RT.) Pressure is force per unit area and so is dimensionally the same as energy per unit volume (e.g., 1 Pa = 1 N m-2 = 1J m-3). Vw has the units of m3 mol-1, so VWP and hence /aw can be expressed in J mol-1. 

The SI is used throughout this book, as explained in the Preface. The system is reviewed in this appendix. Definitions and sufficient conversion factors are presented to enable the reader to understand the system, and to convert SI units to other common energy units used in the United States. Additional information is presented on the equivalencies of a few common U.S. energy units. 

The necessary basic knowledge is provided in Chapter 2 The Chemical Production Plant and its Components. It deals vhth important subdisciplines of technical chemistry such as catalysis, chemical reaction engineering, separation processes, hydrodynamics, materials and energy logistics, measurement and control technology, plant safety, and materials selection. Thus, it acts as a concise textbook vhthin the book that saves the reader from consulting other works when such information is required. A comprehensive appendix (mathematical formulas, conversion factors, thermodynamic data, material data, regulations, etc.) is also provided. 

The cost of electric power was estimated as the sum of four terms. The first is the cost to provide the steam flow (in pph) noted in Table 4.11. That value was converted to a requirement for energy as 945 BTU/lb steam, and the conversion factor of 3415 BTU/kilowatt (kW). The second term was the power cost to continually operate the air amplifier, taken to be a 6 HP motor. The third term was the power cost to operate a 3 HP water pump for condensed water and solvent vapor fed to the decanter. The fourth term is a general allocation of 52 kW for miscellaneous and unspecified needs. This value was taken from the reference of Appendix A2, Footnote 12, page 34. Both the third and fourth terms were corrected for the actual capacity of activated carbon using the six-tenth power rule used to estimate capital investment. The sum has the units of kW hours. 

An observed spectroscopic transition in the hydrogen atom involves the 2/ Is transition. Using Eq. (4-8), evaluate this energy difference in units of hertz (Hz). (1 Hz= 1 s ) Do the calculation using both me and n. (See Appendix 10 for constants and conversion factors.) How much error in this calculation, in parts per million, is introduced by ignoring the finite mass of the nucleus (i.e., using We instead of /u-) ... 

Some useful conversion factors involving energy and mass units are summarized in Table 1.2 for a more detailed listing of fundamental constants and conversion factors see Appendix (Tables A.l and A.2). 

Chapter 7 foUows this latter approach of treating individual separation processes under each of the three broad categories of separation processes when the bulk flow of feed-containing phase is perpendicular to the direction of the force. Chapter 8 foUows the same approach when the buik flows of two phases/regions in the separator are perpendicular to the direction(s) of the force(s). Chapter 9 briefly elaborates on cascades, which were already introduced in the countercurrent multistaged flow systems of Chapter 8. Chapter 10 introduces the energy required for a number of separation processes. Chapter 11 illustrates a few common separation sequences in a number of common industries involved in bioseparations, water treatment, chemical and petrochemical separations and hydro-metaUurgy. Conversion factors between various systems of units are provided in an Appendix. 

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