Heating Saturated Air in an Incinerator

[mehtasoham]

I need help to understand heating requirement in an incinerator meant for aqueous wastewater;

The wastewater is evaporated in a primary chamber and then the gases are required to be heated to 1200 deg.C in a secondary chamber with 2 seconds residence time. The operating pressure is just about atmospheric. In calculating the heat input, do I need to consider specific heat of water vapors being raised to a temp. of 1200 deg.C? Is it possible that water vapors in the air will rise to this temperature without being pressurized? Given the 2 seconds residence time, will both air and water vapors reach that temperature together?

 

[Aaron Barnard]

Yes, you need to consider the specific heat of water vapor when calculating the heat input for an incinerator meant for aqueous wastewater. The water vapors in the air will not necessarily reach a temperature of 1200 degrees Celsius without being pressurized. Depending on the type of incinerator and the air pressure, it is possible that both air and water vapors could reach that temperature together in two seconds. However, it is important to note that the higher the air pressure, the easier it is for the water vapor to reach a higher temperature due to the increased pressure. Additionally, the efficiency of the combustion process and the type of fuel being used can also affect the amount of heat needed to reach the desired temperature.

 

[astrokreng]

I can provide some insights on the heating requirements for an incinerator meant for aqueous wastewater. In order to heat the saturated air in the incinerator, we need to consider the specific heat of water vapors, as they will also contribute to the overall temperature of the gases in the secondary chamber. The specific heat of water vapors is higher than that of air, so it will require more energy to raise their temperature to 1200 deg.C. Therefore, it is important to consider the specific heat of water vapors in your calculations for heat input.

In terms of pressurization, it is possible for water vapors to reach a temperature of 1200 deg.C without being pressurized. However, the temperature and pressure of the gases in the secondary chamber should be carefully monitored and controlled to ensure safe and efficient operation of the incinerator.

Given the short residence time of 2 seconds, it is unlikely that both air and water vapors will reach the target temperature of 1200 deg.C simultaneously. The air, being less dense, will reach the target temperature faster than the water vapors. However, it is important to ensure that both the air and water vapors reach the target temperature before exiting the secondary chamber to ensure proper incineration of the wastewater.

In conclusion, the specific heat of water vapors should be taken into consideration in calculating the heat input for an incinerator meant for aqueous wastewater. The temperature and pressure of the gases in the secondary chamber should be carefully monitored and controlled, and the residence time should be optimized to ensure efficient and safe operation of the incinerator.