How to calculate the dehumidification capacity of air conditioning box from the difference in air moisture content?

The theoretical dehumidification capacity of the air-conditioning box can be calculated by multiplying the dry air mass flow rate by the difference in moisture content before and after treatment. Moisture content is expressed in terms of the mass of water vapor per kilogram of dry air and cannot be directly subtracted from the relative humidity percentage. Calculations also need to confirm air conditions, mass flow apertures and whether there are other sources of moisture in the system.

Write the three calculated quantities in full units

Assume that the dry air flow rate is 10,000 kg/h, the inlet moisture content is 14 g/kg, the outlet moisture content is 8 g/kg, and the theoretical dehumidification capacity is about 60 kg/h. The 6 g/kg in the example must first be replaced with 0.006 kg/kg. If there is only m³/h air volume, the dry air mass flow rate should be converted according to the corresponding air state, and the temperature, humidity and altitude conditions cannot be ignored.

The air flow rate adopts the mass flow rate of dry air passing through the dehumidification section; the moisture content difference requires that both the inlet and outlet use the same dry air reference; the time unit is converted between kg/s and kg/h before calculating the water volume. For the relationship between air volume and mass flow, please refer toHow to convert the air volume units of air conditioning box in m³/h, L/s and CFM? . If you only know the relative humidity on site, you need to know the temperature at the same time to convert the moisture content. You can refer toWhy does air conditioning box selection depend on relative humidity and temperature?。

How to use calculation results for engineering verification

This result corresponds to the reduction of moisture in the air and is not automatically equal to the drainage volume measured at any time in the drain pan. Starting and stopping water storage, airflow carrying water or poor drainage may cause short-term readings to be different. The coil must also meet the corresponding heat exchange status, and the equipment cannot be specified based only on the dehumidification volume number without omitting the cold water temperature and air outlet requirements.

How does the air inlet and outlet status of the coil affect the selection? Please refer toHow to select the type of air conditioner cooler according to the air inlet and outlet conditions? ;How to confirm the cold water parameters, please refer toWhat water parameters should be confirmed before connecting the air conditioning box to the cold water system? . The water tray and drainage layout will also affect the actual drainage performance. Please refer toHow to combine the slope of the water pan of the air-conditioning box with the layout of the drain outlet?。

Dehumidification capacity is not equal to cooling capacity

Dehumidification describes the reduction of moisture on the air side, while cooling includes sensible heat and latent heat. Condensation and dehumidification will occur only when the air is cooled below the dew point. The part of the total cooling capacity used for moisture condensation and the part used for cooling need to be checked separately. By only giving a dehumidification number, it is impossible to judge whether the coil can reach the target temperature and moisture content at the same time. When comparing plans, you should also check the total cooling capacity, sensible cooling capacity, air outlet status and cold water conditions. For the relationship between dew point and moisture control, please refer toWhat role does the supply air dew point play in the selection of fresh air air conditioning boxes?。

What to do when there are other sources of moisture in the system

What is calculated is the moisture reduced by the air treatment in this section, which is not equal to the total moisture load of the room. Moisture dissipation from personnel, processes, penetration by opening doors and introduction of fresh air are all possible sources of moisture in the room. If the goal is to control room humidity, you should first balance the moisture in the room and then determine how much dehumidification task the air-conditioning box will undertake. Confusing the unit's dehumidification capacity with the room's humidity load may lead to equipment selection that is too small or too large. For the division of room load and unit tasks, please refer toWhat indoor loads should the circulating air handling unit be selected based on?。

Aili industrial supporting equipment

When submitting a dehumidification task to Aili Industrial, the air volume and the moisture content of the inlet and outlet air can be provided at the same time, making it easy to check the coil selection, water connection and drainage conditions under the same working condition. Aili Industrial can jointly confirm coils, water trays, drainage structures, fans, and control configurations; the manufacturing end covers motors, fans, control systems, sheet metal, air filters, and complete machine assembly. The interfaces between the dehumidification section and the front and rear functional sections can be aligned in the same package.

Product form can be viewedAir handling unit andFan box page; if gaseous pollutants need to be controlled, please communicate separatelyChemical filter solution; clean air supply end can be combinedFFU fan filter unit andHEPA/ULPA filter verification. The specific dehumidification effect, applicable environment and operating conditions still need to be verified based on the corresponding configuration data and on-site working conditions. Actual results are subject to on-site leak detection and performance test results.

Submit project parameters:https://ailigy.com/contactus.html

Related questions and answers

Can dehumidification capacity be calculated directly by subtracting relative humidity?
cannot. Relative humidity is a proportional value, and the calculation of dehumidification requires a difference in moisture content, which is expressed in terms of the mass of water vapor per kilogram of dry air.

Is the theoretical dehumidification capacity equal to the actual drainage capacity?
uncertain. Starting and stopping water storage, airflow carrying water and poor drainage will make the short-term drainage volume different from the theoretical value, which should be judged based on the operating status.

Can Aili Industrial help check the dehumidification configuration?
The coil and drainage configuration can be checked based on the air volume, inlet and outlet air moisture content, and cold water conditions. The specific plan needs to be confirmed based on the project conditions.

Related articlen=linkage

1. Why does air conditioning box selection depend on relative humidity and temperature?

2. How to select the type of air conditioner cooler according to the air inlet and outlet conditions?

3. What role does the supply air dew point play in the selection of fresh air air conditioning boxes?

4. How to combine the slope of the water pan of the air-conditioning box with the layout of the drain outlet?

Key points for selection and acceptance inspection