Material Flow Section - HOC
Navigation: Models ➔ Common Sections ➔ Material Flow Section ➔ Heats of Combustion, Heating Values
| Material Flow (Qo) | Qxxxx Tab Include Properties | Species Flow | Optional Tabs | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Basic Information | Energy ValuesAtUserTandP | Density Correction Solubility Saturation | Acidity Charge Transport | HeatsOfCombustion Heating Values | Solution Impurity H2O Properties | Water Quality | Sp Tab EC Tab | DLockup LockUp | DTrack Track | DSz Sz MSz | DSSA SSA |
Related Links: Common Content Section
This section is used to display the included properties for: Heats of Combustion (Build 139 and later) and Heating Values (Build 138 and earlier)
Heats of Combustion
| Tag (Long/Short) | Input / Calc | Description/Calculated Variables / Options | |||||||||
Heat of CombustionOnly available in Build 139 or later. For Build 138 or earlier, refer to Heating Values. These will only be shown if the user has chosen to display the HeatsOfCombustion Properties on the Plant Model - Views tab page or from the Include Properties dropdown list on the first page of the material Flow section. The Heat of Combustion is the heat released (i.e. enthalpy change) if the stream components undergo complete combustion with oxygen to produce carbon dioxide gas and water. The higher heating value (HHV) (or Gross Calorific Value) is calculated by assuming that the water produced is liquid water. The lower heating value (LHV) (or Net Calorific Value) is calculated by assuming that the water is produced as steam. NOTE:
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| HoC (Heats of Combustion) | |||||||||||
| HHV.M150 | Calc | Higher Heating Value - Heat released if the stream components undergo complete combustion with oxygen to produce carbon dioxide gas and liquid water at 150°C and 1 atmosphere pressure on a mass basis. | |||||||||
| HHV.M25 | Calc | Higher Heating Value - Heat released if the stream components undergo complete combustion with oxygen to produce carbon dioxide gas and liquid water at 25°C and 1 atmosphere pressure on a mass basis. | |||||||||
| HHV.Ml25 | Calc | As above except on a molar basis. | |||||||||
| HHV.V25 | Calc | As above except on a volumetric basis. NB Gas mass per volume calculated at 25°C and stream pressure. | |||||||||
| HHV.M | Calc | Higher Heating Value - Heat released if the stream components undergo complete combustion with oxygen to produce carbon dioxide gas and liquid water at the stream temperature and pressure on a mass basis. | |||||||||
| HHV.Ml | Calc | As above except on a molar basis. | |||||||||
| HHV.V | Calc | As above except on a volumetric basis. NB Gas mass per volume calculated at the stream temperature and pressure. | |||||||||
| LHV.M150 | Calc | Lower Heating Value - Heat released if the stream components undergo complete combustion with oxygen to produce carbon dioxide gas and steam at 150°C and 1 atmosphere pressure on a mass basis. | |||||||||
| LHV.M25 | Calc | Lower Heating Value - Heat released if the stream components undergo complete combustion with oxygen to produce carbon dioxide gas and steam at 25°C and 1 atmosphere pressure on a mass basis. | |||||||||
| LHV.Ml25 | Calc | As above except on a molar basis. | |||||||||
| LHV.V25 | Calc | As above except on a volumetric basis. NB Gas mass per volume calculated at 25°C and stream pressure. | |||||||||
| LHV.M | Calc | Lower Heating Value - Heat released if the stream components undergo complete combustion with oxygen to produce carbon dioxide gas and steam at the stream temperature and pressure on a mass basis. | |||||||||
| LHV.Ml | Calc | As above except on a molar basis. | |||||||||
| LHV.V | Calc | As above except on a volumetric basis. NB Gas mass per volume calculated at the stream temperature and pressure. | |||||||||
Heating Values
Only available in Build 138 or earlier. For Build 139 or later, refer to Heats of Combustion.
The Heating Value is the Heat of Combustion (i.e. heat released, enthalpy change) if the stream components undergo complete combustion with oxygen to produce carbon dioxide gas and water. The higher heating value (Hi) (or Gross Calorific Value) is calculated by assuming that the water produced is liquid water. The lower heating value (Lo) (or Net Calorific Value) is calculated by assuming that the water is produced as steam.
NOTE: The Heating Value is only calculated for components which contain only carbon (e.g. carbon solid), only hydrogen (e.g. hydrogen gas) or only carbon and hydrogen (i.e. a hydrocarbon, e.g. methane (CH4)). Components which contain only carbon and oxygen (e.g. carbon monoxide) and only carbon, hydrogen and oxygen (e.g. ethanol) are also included.
These heating values will only be shown if the user has chosen to display Heating Values using the ShowHeatingValues tickbox.
| Tag (Long/Short) | Input / Calc | Description/Calculated Variables / Options |
| Heating Values (Combustion) | ||
| HVHiM | Calc | Heating Value - Heat released if the stream components undergo complete combustion with oxygen to produce carbon dioxide gas and liquid water at the stream temperature and pressure on a mass basis. |
| HVHiMl | Calc | As above except on a molar basis. |
| HVHiV | Calc | As above except on a volumetric basis. |
| HVHiNV | Calc | As above except on a normal volume basis. |
| HVLoM | Calc | Heating Value - Heat released if the stream components undergo complete combustion with oxygen to produce carbon dioxide gas and steam at the stream temperature and pressure on a mass basis. |
| HVLoMl | Calc | As above except on a molar basis. |
| HVLoV | Calc | As above except on a volumetric basis. |
| HVLoNV | Calc | As above except on a normal volume basis. |
| HVHiM25 | Calc | Heating Value - Heat released if the stream components undergo complete combustion with oxygen to produce carbon dioxide gas and liquid water at 25°C and 1 atmosphere pressure on a mass basis. |
| HVHiMl25 | Calc | As above except on a molar basis. |
| HVHiV25 | Calc | As above except on a volumetric basis. |
| HVHiNV25 | Calc | As above except on a normal volume basis. |
| HVLoM25 | Calc | Heating Value - Heat released if the stream components undergo complete combustion with oxygen to produce carbon dioxide gas and steam at 25°C and 1 atmosphere pressure on a mass basis. |
| HVLoMl25 | Calc | As above except on a molar basis. |
| HVLoV25 | Calc | As above except on a volumetric basis. |
| HVLoNV25 | Calc | As above except on a normal volume basis. |
If oxygen gas and/or carbon dioxide gas are not included in the project then the following numbers will be assumed when calculating the heat values (all values are at 298K).
|
Species |
Heat of Formation (Hf) (kJ/mol) |
Heat Capacity (Cp) (J/K.mol) |
| Oxygen (O2(g)) | 0 | 29.379 |
| Carbon Dioxide (CO2(g)) | -393.8 | 37.171 |
Reference: The Properties of Gases and Liquids, 4th Edition (Reid, Prausnitz and Poling)