In industries or factories, indoor air without exhaust ventilation leads to worker’s discomfort, damages to costly and sophisticated equipment, etc. Thus, these kinds of issues generate the need to install industrial pressurized ventilation system at the workspace. Industrial ventilation system in factories ensures a comfortable, safe, controlled, and dust-free working atmosphere.
The supply of fresh and natural air from the outside to inside depends upon the difference between outside and inside temperature. Outside air will not automatically flow into the building unless a breeze is blowing in the same direction. Nor will the warm air flow out from the building, unless the outside air is cooler than the inside air. Consequently, natural ventilation is less effective in hot windless weather. Furthermore, there can be no control over the ingress of dust inside the building with incoming air. Thus, forced ventilation systems are necessary to install into industries. Air pressure and ventilation system are employed these as follows.
- Air Extraction/Exhaust of Air System
- Air Supply System
- Combination of Air Extraction and Air Supply System
Let’s explore all components of pressurized ventilation system, one by one –
Air Extraction/Exhaust of Air
Properly designed exhaust systems work to remove dust and contaminants from the inside air, but these industrial ventilation system will not work to draw fresh air into the department. Thus, it will cause generating negative pressure on the building and further lead to many undesirable results. So, in order to achieve desired ventilation, mechanical air supply systems are preferred.
Air Supply Systems
Air Supply systems work to throw used air from inside to outside using a pressurized effect, and blow up fresh air into the occupied space with the help of inbuilt fans. These components of pressurized ventilation system provide the best solution to introduce fresh air inside the building in a positive manner. With this positive air pressure ventilation system, interior air can be achieved more conveniently by maintaining reasonable control over it.
Combination of Exhaust and Supply Systems
At the workspace, full control of ventilation can be achieved by using both air supply and air exhaust systems. Uniform distribution of fresh air supply can be ensured and used air could be let out, as per the requirement. Under such industrial ventilation system, the input fans can be selected to give about 20% more air volume than the exhaust fans. Thereby, keeping the building atmosphere at higher pressure than outside leads to reducing ill effects of infiltration due to dust and other air-borne contaminants.
- Certain norms that could be followed to make an Industrial Evaporative Cooling Cum Pressurization Plant successful, are given below –
- air pressure and ventilation system can minimize external heat loads by shading, reflective painting, insulating, etc.
- Minimize internal heat loads by shielding, reflective painting, insulating, and providing exhaust fans over each hot process.
- Use all fresh air with no recirculation in pressurized ventilation system.
- Use grille velocities of 6-8 m/sec. to induce maximum air movements.
- Calculate necessary evaporative cool air volume from known heat loads. Also, avoid the basis of air changes per hour for industrial applications.
- In positive air pressure ventilation system, the cracking area should be kept minimum to create pressurization effect. It can be done by sealing all the unnecessary openings to economize the plant capacity.
- Avoid vigorous evaporative cooling for rooms such as offices and laboratories, where high indoor air velocities are not permissible.
- Open large enclosures can use spot-cooling for people working at work stations.