Print this page Overview of Vapor Absorption Chilling Systems
A. Bhatia, B.E.
Course Outline
"How can you
have cooling with heat?"
This 4-hour course describes, the vapor absorption chiller machine (VAM) that
uses heat to produce chilled water for process or comfort cooling. In general
the VAM finds applications in
- Large Tonnage Space Cooling
- Industrial Process Cooling
- Cogeneration Waste Heat utilization
- Waste-to-Energy
utilization
The course is intended for use primarily to the students, end users, consultants, architects, contractors and HVAC designers.
This course includes
a multiple-choice quiz at the end, which is designed to enhance the understanding
of the course materials.
Learning Objective
At the conclusion of this course, the student will:
- Be knowledgeable about the " Vapor Absorption Refrigeration Machine";
- Be knowledgeable about the economics of VAM; and
- Be able to conceptualise,
judge and select the right system.
A vapor absorption
refrigeration system is heat energy driven unlike the conventional vapor compression
system, which uses a motor driven compressor. VAM uses only small fraction of
electricity as compared to the conventional vapor compression chillers.
VAM uses a heat source that could be steam/hot water or it could be direct fired
using gas or oil. Steam fired absorption finds application where a low cost
steam can be generated from a waste energy plant in the process industry application.
The direct-fired units find justification where electricity prices are high
or where non-ozone depleting refrigerants are a concern.
Today's modern absorption chillers range from around 90 tons to 2000 tons. Larger
tonnages (above 500 tons) have a more favorable first cost when compared to
electric technologies. The economics of operating costs vary depending on the
energy used.
Course Content
The the course content is in a PDF file Overview of Vapor Absorption Chilling Systems. You need to open or download this document to study this course.
Course SummaryA vapor absorption
chiller (VAM) is a machine to produce chilled water using heat source such as
steam, hot water, gas, and oil. The VAM for commercial air-conditioning application
use lithium bromide (Li Br)-water as absorbent-refrigerant pair.
The single effect VAM generally works on steam/hot water and require about 18pph
per ton of 9-psig steam at the generator flange at ARI standard rating conditions.
The double effect VAM are more efficient than the single effect machine that
are either direct fired or utilize high-pressure steam. The steam driven units
require about 9 to 10 pph per ton of 114 psig input steam at ARI standard rating
conditions. Double effect gas-fired units require an input of about 10,000 to
12,000 Btuh HHV per ton of cooling at ARI standard rating conditions.
The VAM uses non-ozone depleting refrigerants and rely on very less electricity
as compared to the vapor compression systems.
The VAM provides immense benefit particularly for an industrial application
where there is a possibility of tapping waste heat to generate steam/hot water.
The cooling can be available for free.
Related Reading
Six Ways to
Perform Economic Evaluation of Projects
When you decide to implement a Building Automation System, you must take into
consideration all the fixed and variable costs. Since the cost of BAS alone
is significant portion of the project costs, it is wise to carry out the life
cycle assessment before implementing. A course titled 'Six
ways to perform economic evaluation of projects' provides techniques
to carry out the financial analysis of new or retrofitting projects. This is
a generic 2-hour course recommended for the project advisors, architects and
project engineers.
HVAC made Easy
- Selection Tips for Vapor Compression Machines
Commercially, the most of the chilling installations for comfort and process
cooling work on the use of vapor compression machines. A 2-hour course titled
"HVAC made Easy - Selection Tips for Vapor Compression
Machines" provides insight to the different vapor compression chiller
options such as reciprocating, screw or centrifugal chillers
Once
you finish studying the
above course content,
you need to
take a quiz
to obtain the PDH credits.
DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDHonline.com or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered professional engineer. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.
