What does Wobbe index measure?
What does Wobbe index measure?
The Wobbe Index (WI) or Wobbe number is an indicator of the interchangeability of fuel gases such as natural gas, liquefied petroleum gas (LPG), and town gas and is frequently defined in the specifications of gas supply and transport utilities.
What does high Wobbe index mean?
The Wobbe index is a measure of the interchangeability of gases when they are used as a fuel. It compares the energy output of different gases during combustion. The Wobbe index may be calculated from the higher heating value (HHV) and the specific gravity of the gas.
What is Wobbe number?
The Wobbe Number or Wobbe Index describes the way in which the gas burns and is calculated as a factored ratio of CV and specific gravity (SG otherwise known as relative density).
How can I reduce my Wobbe index?
To decrease the Wobbe Index of the natural gas, for example, a lower (or preferably zero) Wobbe Index component is added to create a blend. Options for this component include nitrogen (N 2) and carbon dioxide (CO 2). Alternatively, the Wobbe Index of the tail gas could have been increased.
What is Modified Wobbe index?
The Modified Wobbe Index is a calculated. measurement of volumetric energy content of. fuel and is directly related to the fuel tempera- ture and lower heating value (LHV).
What is the gross calorific value?
Gross calorific value is the amount of heat produced as a result of the complete combustion of a unit volume of a substance. It is the absolute value of the specific energy of combustion for a unit mass of a substance. We can generally call it calorific value or high heating value.
What does higher heating value mean?
gross calorific value
The higher heating value (also known gross calorific value or gross energy) of a fuel is defined as the amount of heat released by a specified quantity (initially at 25°C) once it is combusted and the products have returned to a temperature of 25°C, which takes into account the latent heat of vaporization of water in …
What is the Wobbe number of natural gas?
Pure methane has a Wobbe number of 1363; natural gas as piped to homes in the United States typically has a Wobbe number between 1310 and 1390.
What happens when you burn propane?
Propane undergoes combustion reactions in a similar fashion to other alkanes. In the presence of excess oxygen, propane burns to form water and carbon dioxide. Complete combustion of propane produces about 50 MJ/kg of heat. Propane combustion is much cleaner than that of coal or unleaded gasoline.
What is the heating value of hydrogen?
120-142 MJ/kg
Heat Values of Various Fuels
| Heat value | |
|---|---|
| Hydrogen (H2) | 120-142 MJ/kg |
| Methane (CH4) | 50-55 MJ/kg |
| Methanol (CH3OH) | 22.7 MJ/kg |
| Dimethyl ether – DME (CH3OCH3) | 29 MJ/kg |
What is the difference between gross and calorific value?
The key difference between net calorific value and gross calorific value is that net calorific value is the amount of heat that is created when water is converted into water vapor upon combustion of a material, whereas gross calorific value is the amount of heat created when water is converted into water vapor and back …
Which fuel has more calorific value?
hydrogen
Calorific value is nothing but the energy contained in a fuel or food, determined by measuring the heat produced by the complete combustion of a specified quantity of it. This is now usually expressed in joules per kilogram. Hence, hydrogen has the highest calorific value.
What is the difference between Wobbe index and calorific index?
Wobbe index is an indicator of the interchangeability of fuel gases whereas Calorific value is the total amount of heat energy that a unit mass of fuel can produce when we burn it completely. Therefore, this is the key difference between wobbe index and calorific value.
What is the calorific value of LPG?
LPG is the abbreviation of “liquefied petroleum gas”. It is a mixture * of propane and butane. The calorific value of domestic LPG is about 116 MJ/m3 and its flammable limits are approximately 1.8 ～ 9.5%. The Wobbe Index of LPG is 84. LPG is colourless, odourless, non-toxic, flammable, explosive and heavier than air.
What is the calorific value of fuel?
Calorific value is the total amount of heat energy that a unit mass of fuel can produce when we burn it completely. Therefore we can define it as the efficiency of fuel. We can use different units to measure this value.
What is the calorific value of town gas?
Its major components are nitrogen, methane, carbon dioxide and a small amount of carbon monoxide. Its calorific value is about 17.27 MJ/m3 and its flammable limits are approximately 4.5 ～ 44.3%. The Wobbe Index of town gas is 24.
