Energy Recovery Systems - Atlas Copco GA 75+ Instruction Book

Reference
BV1
Field installation
The main components are assembled ex-factory as a compact unit which fits inside the bodywork of the
compressor. Consult Atlas Copco for installing and connecting the energy recovery unit.
6.2

Energy recovery systems

General
The energy recovery systems can be applied as low temperature rise/high water flow systems or as high
temperature rise/low water flow systems.
Low temperature rise/high water flow systems
For this type of application, the temperature difference between the water in the energy recovery system and
the compressor oil is low. As a consequence, a high water flow is needed for maximum energy recovery.
Example: The heated water is used to keep another medium at a moderately high temperature, in a closed
circuit, e.g. central heating.
High temperature rise/low water flow systems
For this type of application, a high water temperature rise in the energy recovery system is obtained, which
consequently brings on a low flow rate.
Example: An open circuit where cold water from a main supply is heated by the energy recovery system for
use in a factory, e.g. pre-heating of boiler feed water.
Recovery water flow
The recovery water enters the unit at inlet connection (1). In heat exchanger (HE) the compression heat is
transferred from the compressor oil to the water. The water leaves heat exchanger (HE) via outlet connection
(2).
Water requirements for closed water circuits
The use of a closed water circuit minimises make-up water requirements. Therefore, the use of soft or even
demineralised water is economically feasible and eliminates the problem of scale deposits. Although the heat
exchanger is made of stainless steel, the water circuit connected to the compressor may require corrosion
inhibitors. Consult section
any doubt, consult Atlas Copco.
Add an anti-freeze product such as ethylene-glycol to the water in proportion to the expected temperature to
avoid freezing.
140
Designation
Location of oil cooler bypass valve (BV1)
Cooling water requirements to minimise problems due to bad water quality. If in
Instruction book
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