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<DIV><FONT face=Arial size=2>Dear Mohammed Aliyu</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>The very important information is at what
temperature you are operating the environment to dehumidify.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Example 1. In a very wet climate,
(Angola), a large textile mill (cotton spinning frames), could not operate
due to high humidity of the environment causing breakages and other
problems. They sorted the problem for a while reducing the capacity of the
evaporative air conditioning and leting the temperature raise to almost
40ºC. At this temperature without removing any water from
the ambiente, the resulting RH reached 45/55%. The
conditions were terrible for the personell and the whole operation had to be
moved to the plateau with cooller and dryer environment.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Example 2. To maintain 0,0%
RH, ( to be precise a dewpoint of -50ºC), in a closed small
environment, with a temperature of 23ºC. The system that we specified had
two big housings with silica gell. Working in tandem, while one of
the systems was dehumidifying the others was being regenerated with electric
heaters. Cooling was assured with some DX equipment, nothing
complicated. Works but expensive.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>You need to calculate you sensible and latent
loads. Dividing the sensible load by the total load you get the
sensible heat factor for the process. Place your entering
point in the chart and strike a line from this point in the direction of
the saturation curve with the slope of the SHL. If this line does not
cross the saturation line then your process is impossible with the refrigeration
alone. You need Reheat. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>If you give me some more detail I can
send you the guidelines for your project plotted on a chart.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Best regards</FONT></DIV>
<DIV><FONT face=Arial size=2>Eduardo Barrigana</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=mannir2003@yahoo.com href="">mohammed aliyu</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=bldg-sim@lists.onebuilding.org
href="mailto:bldg-sim@lists.onebuilding.org">bldg-sim@lists.onebuilding.org</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Tuesday, May 12, 2009 9:41 AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> [Bldg-sim] In search of
Dehumidifiers</DIV>
<DIV><BR></DIV>
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<P>Hello All,</P>
<P></P>
<P>Im about to carry out an experiment by dehumidifying an indoor
environment, so Im seeking for advice on the type of dehumidifier to use
which can lower the humidity by as much as 40-60%. RH reach 100% in
Malaysia frequentyl. Has any one got an idea or experience on the
practical performance of such units?</P>
<P></P>
<P>Regards</P></TD></TR></TBODY></TABLE><BR></BLOCKQUOTE></BODY></HTML>