Fan Management in Industry
Many factories use fans to remove harmful substances and combustion products. However, these systems consume a significant amount of electricity. Mechanical exhaust fans that operate at maximum efficiency demonstrate excellent performance, reduce costs, and greatly enhance return on investment.
Therefore, it is essential to understand how to effectively control and manage such fans to achieve energy efficiency in production processes.
Airflow Control Methods
Methods and devices for managing airflow can significantly impact energy savings. Various methods have their advantages and disadvantages when it comes to controlling flows using fans. In this article, we will discuss the pros and cons of two specific methods: damper control and frequency converter control.
The Purpose of Draft Control
Draft control is relevant because boilers were created decades ago. They had a brick structure that required operation under negative draft or balanced pressure. Negative pressure was used to cool the furnace to prevent positive pressure from entering the boiler, which could lead to damage to the casing or injury to personnel.
However, even in modern airtight boilers, draft control is needed, primarily due to the recirculation of flue gases to control harmful emissions. Failure to maintain draft control can lead to excessive emissions of harmful substances, increased operating costs, and reduced efficiency.
Damper Control
One of the traditional methods is the use of dampers to control the volumetric air flow. This old method is still actively used in various systems and types of boilers.
Advantages
- Damper control is a cost-effective method when considering only the purchase price.
Disadvantages
- This method is not the most effective for controlling gas or air flow.
- Damper control requires regular maintenance due to the presence of more moving parts compared to variable speed drives.
Frequency Converter Control
Variable speed drive (VSD) and variable frequency drive (VFD) are modern methods for maintaining draft control in ventilation systems. Although there are differences between these two methods, they are both used to describe one type of equipment.
Advantages
- VSD/VFD control provides significant energy savings compared to damper control.
- Using VSD/VFD control elements can also reduce the cost of purchasing a motor if a bypass is not necessary.
- The overall cost of the VSD/VFD system may be more advantageous in the long term compared to damper control.
Disadvantages
- The initial cost of the VSD/VFD system exceeds the cost of a simple damper system.
Conclusions
Draft control for fans is critically important. Both described methods: damper control and VSD/VFD control have their advantages and disadvantages.
Choosing the right system can maximize return on investment, reduce costs, and enhance overall productivity of all processes.