Heat/Mass Balance Module

Heat balance calculations are needed to estimate the energy requirements and the cost of the process, as well as the operation preconditions. In fact no process will work if the heat balance is not met.

Input and output species, with their amounts and temperatures, are specified initially. HSC recalculates the heat balance every time the initial conditions are changed. In this way you can, for example, find the optimum preheating temperature for raw materials to offset external heating of a reactor system.

Theoretical heat balances can take species and amounts from the reaction equations or equilibrium calculations. Real heat balances can be calculated by taking species and amounts from experimental results.

The Temp Bal button is used to get product temperature at zero heat balance. In the case of gaseous combustion processes with zero heat exchange to the environment, this yields the adiabatic flame temperature.

Both input and results can be saved as text files. This assures the files will be available later for editing in HSC or use in other programs.

Heat Loss Module. The new Heat Loss module may be used to estimate heat loss values needed in the Balance module. The user must first specify the wall layers, layer materials and thickness of these layers. Two basic types of calculations may be carried out:

• Temperature profile with fixed heat loss and one temperature point.
• Heat Loss with two fixed temperature points will return the heat loss but also the temperature profile.

The calculation routine handles conduction, convection and radiation properties as functions of temperature but fixed values may also be used by selecting the value and pressing the Fix Value button. These fixed values are shown in red on the calculation sheet.

Temperature profile as well as some other user specified values may also be presented in graphical form. Target dialog may be used to find, for example, minimum layer thickness. The calculation specifications may be saved to files for later use.

The Heat Loss module is integrated with three databases and two calculators:

• Conduction database with 718 substances
• Convection database with 111 substances and 4 functions
• Radiation database with 61 surface materials
• Gas Radiation Calculator with data for H₂O, CO₂, CO, NO, SO₂ and CH₄.
• Particle Radiation Calculator
• The user may edit or add new data to these databases.

Click below to see screenshots relative to the Heat/Mass Balance Module.

• Heat/Mass Balance screenshot
• Heat Loss Calculation Screen
• Gas Mixture Radiation Calculator
• Particle Suspension Radiation Calculator
• Heat Loss Database screen