Air conditioning is a familiar phenomenon in households and public spaces around the world.
Air Conditioning and
Humidification
INTRODUCTION
Air
conditioning is a familiar phenomenon in households and public spaces around
the world. Its application for comfort means the provision of warm (achieved by
heating or cooling), filtered air. High moisture content or humidity is
oppressive, but a low humidity may cause irritation by excessive loss of
moisture from the skin. In some climates, steps may be taken to add or remove
water vapor from the air. The air is cleaned, usually by passage through a
fabric filter, which may be dry or moistened with a viscous liquid, and heated
elec-trically or by banks of finned tubes supplied with steam or hot water over
which the air is blown. Electrostatic precipitation provides an alternative
method of air cleaning. The fine particles entrained in the air are charged by
the absorption of electrons as they pass between two electrodes. The charged
particle then migrates in the electrical field and is finally arrested on one
electrode.
The
same general principles apply to the supply of air in some pharma-ceutical
processes. However, the control of its quality may be more stringent. In areas
in which sterile materials are made and handled, for example, the air cleaning
must remove bacteria. In other processes, it may be necessary to remove water
vapor. The flow of powders is a sensitive function of moisture content. The
equilibrium moisture content of a material is determined by the humidity. Some
tabletting processes break down if the humidity is too high. In such processes,
the scale of the air conditioning varies. It may be necessary to supply a whole
room with air of a certain quality. Alternatively, conditioning may be
restricted to a small area surrounding a particular piece of equipment.
TH 2019 - 2023 pharmacy180.com; Developed by Therithal info.