Category Archives: Fluid Properties

MBBR Nitrification Denitrification Spreadsheet

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Where to Find an MBBR Nitrification  Denitrification Spreadsheet

To obtain an MBBR Nitrification Denitrification spreadsheet, click here to visit our spreadsheet store.  This Excel spreadsheet is intended for MBBR nitrification denitrification process design calculations. You can buy a convenient MBBR Nitrification Denitrification spreadsheet  for a very reasonable price.  This spreadsheet makes MBBR process design calculations for BOD removal, nitrification, and denitrification. including both pre-anoxic and post-anoxic denitrification processes.  It is available in either U.S. units or S.I. units.  Read on for information about using an MBBR process design calculations spreadsheet for nitrification and denitrification.

Background for MBBR Nitrification Denitrification Spreadsheet

The moving bed biofilm reactor (MBBR) appeared relatively recently on the wastewater treatment scene.  It was developed in the 1990’s, and is now used in many countries around the world.

The MBBR wastewater treatment process is quite flexible.  It is used for domestic and industrial wastewater treatment and can be designed for BOD removal alone or in combination with nitrification or with nitrification and denitrification.  It is used as a single stage process or as a two-stage or three-stage process.

The diagram below shows the general configuration of a Pre-anoxic nitrification denitrification MBBR wastewater treatment process.  Denitrification can also be carried out in a Post-Anoxic nitrification denitrification process.

MBBR Nitrification Denitrification Spreadsheet flow diagram

MBBR Pre-Anoxic Nitrification Denitrification Flow Diagram

 Example MBBR Wastewater Treatment Design Spreadsheet

An example MBBR nitrification denitrification spreadsheet is partially shown in the two images below.  This Excel spreadsheet can be used to calculate the required MBBR tank volume and dimensions, based on user input media information and wastewater design flow and characteristics.  This Excel spreadsheet, as well as others for wastewater treatment process design calculations, is available in either U.S. or S.I. units for a very reasonable price in our spreadsheet store.

MBBR Nitrification Denitrification Spreadsheet Screenshot1

Screenshot1 – Pre-anoxic Nitrification Denitrification

MMBR Nitrification Denitrification Spreadsheet Screenshot2

Screenshot2 – Pre-anoxic MBBR Nitrification Denitrification Spreadsheet

 References:

1. McQuarrie, J.P. and Boltz, J.P., Moving Bed Bio-film Reactor Technology: Process Design and Performance, Water Environment Research, Vol 83, No 6, June 2011.

2. Bengtson, Harlan, “MBBR Denitrification Design Spreadsheet,” an online blog article

3. Bengtson, Harlan H., “Biological Wastewater Treatment Process Design Calculations,” available as an Amazon Kindle ebook or as a paperback.

4. Bengtson, Harlan H., “Spreadsheets for MBBR Denitrification Design Calculations,” an Amazon Kindle ebook.

5. Bengtson, Harlan H., “Spreadsheets for MBBR Process Design Calculations,”  available as an Amazon Kindle ebook or as a paperback.

Sutherland Formula Viscosity Calculator

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Where to Find a Sutherland Formula Viscosity Calculator Excel Spreadsheet

To obtain a Sutherland formula viscosity calculator Excel spreadsheet, click here to visit our spreadsheet store.  Look in the Fluid Properties category on the Download page.  This Excel spreadsheet is intended to calculate gas viscosity at a specified temperature using Sutherland’s formula.  You can buy a convenient Sutherland formula viscosity calculator Excel spreadsheet  for a very reasonable price.  This spreadsheet calculates a gas viscosity based on a reference temperature and reference viscosity..  Calculations may be made in either U.S. or S.I. units.  Read on for information about using a Sutherland formula viscosity calculator Excel spreadsheet.

Background for Sutherland Formula Viscosity Calculator Excel Spreadsheet

Sutherland’s formula for calculating the viscosity of a gas at a specified gas temperature is shown below along with an explanation of the parameters in the equation.

Sutherland Formula for Gas Viscosity CalculationThe parameters in Sutherland’s formula are as follows:

To = reference temperature, K

μo = viscosity of the gas at temperature, To

C = Sutherland’s constant for the gas, K

T = the temperature of the gas, K

μ = the viscosity of the gas at temperature, T, in the same units as μo.

Example Sutherland Formula Viscosity Calculator Excel Spreadsheet

An example Sutherland formula viscosity calculator Excel spreadsheet is partially shown in the image below.  This Excel spreadsheet can be used to calculate the viscosity of a specified gas at a specified tempeerature.  This Excel spreadsheet, as well as others for fluid property calculations, is available for both U.S. or S.I. units for a very reasonable price in our spreadsheet store.

Sutherland Formula Viscosity Calculator SpreadsheetReferences

  1. Chapman, S. & Cowling, T. G., “The Mathematical Theory of Non-Uniform Gases, 3rd Ed, 1970, Cambridge Mathematical Library.
  2. National Physical Laboratory, Kaye & Laby, Tables of Physical and Chemical Constants, Chapter 2, Section 2.2, Subsection 2.2.3.
  3. Bengtson, Harlan, Sutherland Law Viscosity Calculator, an informational blog article.
  4. Bengtson, Harlan H., “Gas Property Calculator Spreadsheet,” an Amazon Kindle e-book.

Gas Compressibility Factor Calculator Excel Spreadsheet

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Where to Find a Gas Compressibility Factor Calculator Excel Spreadsheet

To obtain a gas compressibility factor calculator Excel spreadsheet, click here to visit our spreadsheet store.  Look in the Fluid Properties category on the Download page.  This Excel spreadsheet is intended for calculation of the compressibility factor of a gas using the Redlich-Kwong equation of state. You can buy a convenient gas compressibility factor calculator Excel spreadsheet  for a very reasonable price.  This spreadsheet calculates the compressibility factor of a gas from the gas temperature, gas pressure, and the critical pressure and critical temperature of the gas.  It is available in either U.S. or S.I. units.  Read on for information about using a gas compressibility factor calculator Excel spreadsheet.

Background for Gas Compressibility Factor Calculator Excel Spreadsheet

The compressibility factor of a gas is used in several types of calculations including calculation of real gas density.  The Ideal Gas Law, PV = nRT, can be used to calculate the density of a gas that exhibits ideal gas behavior by introducing the molecular weight of the gas and solving for gas density to give:  ρ = MW*P/R*T.
For information on the use of the ideal gas to calculate gas density, see the article, “Air Density Calculator Excel Spreadsheet.”

Conditions required for ideal gas behavior are pressure << critical pressure and/or temperature >> critical temperature.  For gases that don’t exhibit ideal gas behavior, the compressibility factor, Z can be introduced to give:     ρ = Z*MW*P/R*T.

The Redlich-Kwong Equation of State

One possibility for a gas compressibility factor calculator Excel spreadsheet is through the use of the Redlich-Kwong equation of state, which is shown below:

Gas Compressibility Factor Calculator Excel Spreadsheet - Redlich-Kwong Equation of StateA, B, and h are constants calculated as shown.  The compressibility factor, Z, can be calculated for known values of the gas temperature, T, the gas temperature, P, and the critical temperature and pressure of the gas.  The temperatures should be in K and the pressures in atm for use of the equations given above.  Calculation of Z requires an iterative calculation because the equations can’t be solved explicitly for Z.

Example Gas Compressibility Factor Calculator Excel Spreadsheet

An example gas compressibility factor calculator Excel spreadsheet is partially shown in the image below.  This Excel spreadsheet can be used to calculate the compressibility factor of a gas, based on user input values for gas temperature, gas pressure, and the critical temperature and pressure of the gas.  This Excel spreadsheet, as well as others for fluid property calculations, is available in either U.S. or S.I. units for a very reasonable price in our spreadsheet store.

Gas Compressibility Factor Calculator Excel Spreadsheet ScreenshotReferences

1. Otto Redlich, and J.N.S. Kwong, “On the Thermodynamics of Solutions. V. An Equation of State. Fugacities of Gaseous Solutions”, Chemical Reviews 44 pp. 233-244 (1949).

2. Bengtson, Harlan H.,  Redlich Kwong Compressibility Factor Spreadsheet, an informational online blog article.

Air Viscosity Temperature Calculator Spreadsheet

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Where to Find an Air Viscosity Temperature Calculator Spreadsheet

To obtain an Air Viscosity Temperature Calculator excel spreadsheet, click here to visit our spreadsheet store.  Why use online calculators or tables to find the viscosity of air at a specified pressure and temperature when you can buy a convenient air viscosity temperature calculator excel spreadsheet for only $4.95?  This spreadsheet will calculate the viscosity of air at specified pressure and temperature in either U.S. or S.I. units.  Read on for information about Excel spreadsheets that can be used as an Air viscosity temperature calculator for specified pressure and temperature.

Air Viscosity Temperature Calculator Spreadsheet Applications

An  Air Viscosity Temperature calculator excel spreadsheet  can be used for any situation where a value of air viscosity is needed at a specified pressure and temperature.  This could include calculations for air flow in a pipe, drag force or drag coefficient calculations for flow of an object through air, and any other calculation requiring the Reynolds number for air flow or flow through air.  For example, see the related article, Fanno Flow Excel Spreadsheet for Air Flow in a Pipe.

Equations for an Air Viscosity Temperature Calculator Spreadsheet

Equations are available for an air viscosity temperature calculator to calculate the viscosity of air at specified temperature and pressure.  The spreadsheet shown in  the diagram below calculates air density using an equation for air viscosity as a function of temperature ratio, Tr , and density ratio, ρr  , where in U.S. units:  Tr   =  T/238.5 with T in degrees R  and ρr    =  ρ/0.6096 with ρ in slugs/ft3.  Since the air density is needed for this calculation, the spreadsheet also calculates the density of air at the specified air temperature and pressure.  The complete equations are included in the spreadsheet discussed above and shown in the screenshot below.

Example Air Viscosity Temperature Calculator Excel Spreadsheet

The Air Viscosity Temperature calculator excel spreadsheet shown in the image below can be used to calculate the viscosity of air at given temperature and pressure as discussed above.  This Excel spreadsheet and others for fluid properties calculations, in either U.S. or S.I. units are available for very reasonable prices in our spreadsheet store.

Air Viscosity Temperature Calculator Spreadsheet

References

1. Bengtson, Harlan H, “Air Viscosity Calculator Pressure Temperature Spreadsheet,”  An online informational blog article.

Air Density Calculator Excel Spreadsheet

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Where to Find an Air Density Calculator Excel Spreadsheet

To find an air density calculator Excel spreadsheet to use as an air density calculator, click here to visit our spreadsheet store.  Why use an online calculator or look in tables, when you can get an air density calculator excel spreadsheet to use as an air density calculator here? Read on for information about Excel spreadsheets that can be used to calculate the density of air (and other gases) at different pressures and temperatures with the ideal gas law.

Gas density background for an Air Density Calculator Excel Spreadsheet

Pressure and temperature have significant effects on the density of gases, so some means of determining the density of air and other gases at specified temperatures and pressures is needed for a variety of fluid mechanics applications.  Fortunately, the ideal gas law provides a means of doing this for many gases over ranges of temperature and pressure that are of interest.

The Ideal Gas Law for use in an Air Density Calculator Excel Spreadsheet

A common form for the ideal gas law equation is PV = nRT, giving the relationship among T, the absolute temperature of the gas; P, its absolute pressure; V, the volume occupied by n moles of the gas; and R, the ideal gas law constant.

The density of the gas can be introduced into this equation, through the fact that molecular weight (MW) has units of mass/mole, so that n = m/MW.  This leads to the ideal gas law written as:  PV = (m/MW)RT.  Solving this equation for m/V (which is equal to the gas density, ρ) gives the following equation for gas density as a function of its MW, pressure and temperature:  ρ = (MW)P/RT.

A commonly used set of U.S. units for this equation is as follows:

ρ = density of the gas in slugs/ft3,

MW = molecular weight of the gas in slugs/slugmole (or kg/kgmole, etc.) (NOTE: MW of air = 29),

P = absolute gas pressure in psia (NOTE: Absolute pressure equals pressure measured by a guage plus atmospheric pressure.),

T = absolute temperature of the gas in oR (NOTE: oR = oF + 459.67)

R = ideal gas constant in psia-ft3/slugmole-oR.

For conditions under which air can be treated as an ideal gas (see the next section), the ideal gas law in this form can be used to calculate the density of air at different pressures and temperatures.

The air density calculator excel spreadsheet template shown in the screenshot below will calculate the density of a gas for specified molecular weight, pressure and temperature.   This Excelair density calculator excel spreadsheet spreadsheet is available at a very reasonable price in our spreadsheet store and can be used with either U.S. or S.I. units.  These spreadsheets also contain tables of critical temperature and critical pressure for several common gases.

But When Can I Use the Ideal Gas Law to Calculate the Density of Air?

A good question indeed, because air and other gases for which you may need a density value are real gases, not ideal gases.  It is fortunate, however, that many real gases behave almost exactly like an ideal gas over a wide range of temperatures and pressures.  The Critical Temp and Press for Air Density Calculator Excel Spreadsheetideal gas law works best for high temperatures (relative to the critical temperature of the gas) and low pressures (relative to the critical pressure of the gas).  See table at the left for values of critical temperature and critical pressure for several common gases.  For many practical, real situations, the ideal gas law gives quite accurate values for the density of air (and many other gases) at different pressures and temperatures.

S.I. Units for the Ideal Gas Law

The ideal gas law is a dimensionally consistent equation, so it can be used with any consistent set of units.  For SI units the ideal gas law parameters are as follows:

ρ = density in kg/m3,

P = absolute gas pressure in pascals (N/m2),

T = absolute temperature in oK (NOTE: oK = oC + 273.15)

R = ideal gas constant in Joules/kgmole-K

References:

1. Bengtson, Harlan H., Flow Measurement in Pipes and Ducts, An online PDH course for Professional Engineers

2. Munson, B. R., Young, D. F., & Okiishi, T. H., Fundamentals of Fluid Mechanics, 4th Ed., New York: John Wiley and Sons, Inc, 2002.

3. Applied Thermodynamics ebook, http://www.taftan.com/thermodynamics/

4. Bengtson, Harlan H., “Gas Property Calculator Spreadsheet,” an Amazon Kindle e-book.