AIR DUCT SYSTEMS
DESIGNERS & SUPPLIERS OF COMPLETE PLANTS FOR VENTILATION, DUST AND FUME EXTRACTION.
ENVIROVENT is an integrated solutions provider to the global mining, bulk material handling, mineral processing and beneficiation industries, offering innovative technological solutions as well as process and commodity knowledge along the industry value chains. The services range from system design, through to manufacture, turnkey installations and after-sales service, with expertise provided over a full range of environmental control and pneumatic conveying systems.
ENVIROVENT’s in-house air duct range for air pollution control is comprehensive, enabling selection of the most cost-effective solution to any dust-control, air-cleaning or product-recovery problem, large or small. Systems are designed, manufactured and supplied as turnkey installation. In-house maintenance teams, specialised technicians and engineers are locally based, including after-sales service.
AIR DUCT DESIGN
A well-designed air duct system, either commercial or industrial, must consider many system constraints and design factors. Deficiencies in duct design can result in systems that operate incorrectly or are expensive to own and operate. Poorly designed ductwork can result in inadequate airflow rates which may cause blockage and unbalanced systems.
The most common methods of air duct system design are:
✓ Equal Friction method.
✓ Static Regain method.
✓ Constant Velocity method.
Examples of well / poorly designed duct sections:
Systems conveying particulates are designed by the Constant Velocity method at duct velocities adequate to convey particles to the system air cleaner. In a multi-hood system it is necessary to provide a means of distributing airflow between the branches of a junction either by balanced design or by the use of balancing devices.
In general, the balance of flows in multibranch duct systems can be improved by adding resistance to one or more branches. For example, it is possible to change the resistance of either path to attain total pressure balance at the junction. For paths conveying particulates, additional resistance is added to the path of lower resistance by decreasing the duct size or inserting a balancing device, thus maintaining the particulate transport velocity. For paths not conveying particulates, the path with the greater resistance can be increased to attain balance.
ENVIROVENT can design and supply complete balanced air duct systems for Ventilation or supplied Air Environmental solutions.