Air handling system- An overview of Pharmaceutical air handling systems

1. VINOTH R
2061010003
M.Pharm (IP) – 1st Semester

2. CONTENTS
 HVAC systems
 Air handling units
 Air filteration systems
 Dust collectors
 Humidity and temperature control

3.  Heating Ventilation and Air Conditioning systems
are the integral part of environmental control
system design.
Basic components of HVAC:
1. Air Handling Unit
2. Air distribution
 Dust network
 Insulator
 Dampers/valves
 Return lower & grills.
3. Air filters

4.  AHU is a device used to condition and
circulate air as part of a heating ventilating
and air-conditioning (HVAC) system.
 It is a large metal box containing a blower,
heating or cooling elements, filter racks or
chambers, humidity & temperature control
loops.

5.  Temperatures in the 68-74°F (19-23°C) range
is comfortable for working environment.
 Temperature control is important in the areas
where autoclaves, ovens, dry heat
sterilization tunnels are present.
 Humidity comfort levels are in the 45-55% RH
range.
 Air dryers can be used to maintain lower than
normal humidity levels.

6. CONTENTS
 Introduction
 Types of filteration
 Mechanisms of filteration
 Types of air filters

7.  Filteration is an important aspect of
environmental control in Pharmaceutical
industry.
 The main aim of filteration is to produce dust
free atmosphere.
 It is required in areas like spray drying,
coating, granulating, milling, packaging etc.
 Filters are selected based on the required
environment.

8.  Air filteration involves the removal of
unwanted particles due to collision of
particles with the filter.
 Such removal of particles due to collisions are
governed by forces called as
a) Impingement
b) Diffusion
c) Interception

12. Air filter efficiency is
 Maximum – impingement in low velocity
diffusion at high velocities
 Minimum – impingement in high velocity
diffusion at low velocities

13.  Air filters are made up of fibre glass, sinter
glass,
 charcoal, glass wool, dry fabric, oil wetting
fabric.
Purpose:
 final filter
 post filter
 fine filter
 intermediate filter

14. 1. Ultra low penetration and high efficiency
particulate air filters(ULPA & HEPA)
2. Packed towers
3. Membrane filter catridges
4. Hydrophobic filters

16.  MEDIA is the filtering material.Eg: glass fiber,
synthetic fiber, non-woven fiber
 Sealant is the adhesive material that creates a leak-
proof seal between the filter media and the frame.
 Frame is where the filter media is
inserted.Eg:aluminum, stainless steel, plastic or
wood.
 Faceguard is a screen attached to the filter to protect
the filter media during handling and installation.
 Gasket is a rubber or sponge like material used to
prevent air leaks between the filter and its housing by
compressing the two together.

17.  HEPA filter performance is dependent upon
the following characteristics:
 Air flow
 Temperature
 Pollutant loading
 Dust holding capacity
 Filter media
 Construction of HEPA
 Operating conditions etc.

21.  Dust collectors are used for equipment
maintenance.
 Air pollution is controlled.
Main features
 Low cost & maintenance
 Most commonly used for all type of medium
from coarse to fine except <5 microns
particles.
 Collection efficiency of 10 to 100 microns
with multiclones.

22.  1) Dry mechanical collectors
 2) Wet collectors & scrubbers
 3) Fabric collectors
 4) ESP

23.  Collection efficiency is influenced by size,
shape, weight of the particles
 Conc. Of dust & inlet velocity
Types
 Gravity seperators
 Inertial seperators
 Cyclone collectors
 High efficiency centrifugals

24. Collection mechanism:
 Collect the droplets
 Contact particles with water or another liquid
Advantages:
 Can handle high temperature & moisture
 Dust which represent explosion or fire
hazards in the dry form can be wetted and
collected

25. Types:
 Spray dryer
 Packed towers
 Wet centrifugal collectors
 Wet dynamic precipitator
 Venturi type
 Orifice type

26. Mechanism:
 Ionizing the gas
 Charging the dust particles
 Transporting the particles to the collecting
tube
 Neutralizing the dust particles
 Removing the dust from the collecting
surface

27. Advantages:
 Large gas volumes & high collection
efficiency for small particles.
Disadvantages:
 This is a costly method

28. Collection mechanism:
 Impaction
 Interception
 Diffusion
Advantages:
 Can handle varying exhaust gas flow rates &
particle loading

29. The amount of filter area depends on:
 Release characteristics of dust
 Porosity of dust cake
 Conc. Of dust in carrier gas stream
 Type of fabric & surface
 Airflow patternn within the collector
 Temperature & humidity within the gas
stream