During manufacturing of any item there are activities like conveying,transferring,mixing etc. in which lot of dust generates which needs to be collected. When any dust collection system is designed three things to be taken care.

Dust Collection System

1. Capture the dust with proper capture velocity and correct hood design. With this we calculate capacity of the system. Any over design increases fixed cost as well as operation cost due to more power consumption. Undersize will not give desired result.

2. Convey the dust with proper duct velocity. If velocity is less then the required material will settle in the duct and the duct get choked which reduces the suction capacity, Duct size becomes bigger and cost will be more. If velocity is more, then duct size is small which increases pressure drop in turn power consumption is more.

Dust Collection :
Dust collection can be in the dry form or wet form. Hence selection of proper equipment is very important which is based on dust load, particle size analysis, properties of dust & temperature. Based on the above data system can be only with Bag Filter or Venturi Scrubber. If dust load is very high then Cyclone Separator can be used as preliminary separator.

Efficiency
With Cyclone Separator we can achieve 80% to 85% efficiency down to 20micron
With Pulse Jet Bag Filter efficiency can be more than 99% down to 2micron

Generally in chemical industries during manufacturing activities gases like SO2,SO3, NO2, NO3,HF, HCL generates from reactors. These fumes needs to be controlled at source, scrubbed properly and let out clean air to atmosphere.Fume Scrubbing System

Commonly used equipment is Packed Bed Scrubber. Scrubber is filled with packing material like polypropylene pall ring which provides more surface area for contact of gas & liquid. Gas/fumes are sucked from the bottom, liquid is sprayed from the top. When the gas & liquid come in contact with each other, liquid may absorb the gas or it may react with gas.

With this gas transfers to liquid and clean air is let out. Base on gas scrubbing liquid can be water or alkaline solution like NaOH or Na2CO3. Since the gases are corrosive in nature material of construction is PP FRP, PVC FRP or only FRP.

Once the capacity of the system is decided, then size of the scrubber, packing height, flow rate of scrubbing liquid are decided. Efficiency of system generally vary from 90% to 99%.

Any effluent weather it is industry or municipal needs to be treated to control suspended solids, PH, BOD, COD, dissolved solids to prescribed level.Effluent-Treatment

This is generally done by equalization, setting aeration and filtration etc. Based on the nature solid & load various equipment’s are used. Generally based equipment’s are clarifiers

In general engineering industries or godown due to heat load temperature increases in the premises. To provide comfort working condition, it is necessary to ventilate the area so that HVAC Systemtemperature & odor can be controlled to desired level.

In some of the area temperature can be controlled only with ventilation but in hot area where humidity level is low, it is necessary to provide Evaporative cooling system to bring the temperature to desired level.

System capacity is calculated based on heat load & number of air changes required. Pressurization System is generally required to maintain clean manufacturing area or machine room etc. 2 to 3mm pressure is maintained in the area by supplying filtered air in to the room & exhausting naturally through gravity operated damper.

Clean room system:
As per GMP it is necessary to provide clean room system in pharmaceutical industries. It is basically done through properly designed supply & exhaust system.