Egg Industry - May 2018 - 4
4 ❙ EggIndustry
Heat exchangers may be right
for cage-free layer houses
The reduced housing density and litter areas that are part of cagefree housing might make heat exchangers a practical component
of an air handling system for maintaining good air quality and
temperature in wintertime.
Conserving heat while maintaining air quality
Heat exchangers are found all around us, in our car
engines, factories and even to heat and cool our homes.
Broiler houses in Canada have used heat exchangers for over 10 years, while the layer industries in the
EU and other parts of the world have over 25 years
of experience. However, U.S. egg producers have not
traditionally used this technology. Improvements in
design and efficiency coupled with increased building
and retrofitting to incorporate cage-free production
about cage-free hen
health, welfare, www.
systems have allowed an opportunity to revisit the concept. New equipment installations in the U.S. are being
made incorporating heat exchanger technology.
In basic terms, the heat exchanger works with fresh
incoming air being heated by exhausted air being removed
from the building. The two air streams are directed into
channels or tubes of plastic or aluminum that conduct heat
and prevent air flow cross-contamination. By using heat
generated within the house, costs to warm the building are
greatly reduced in the winter. Several equipment manufacturers offer different designs and approaches to the concept.
US heat exchanger installation
The Van Vuuren family has recently installed two
Vencomatic heat exchangers in a barn in the upper
Midwest that was retrofitted to an aviary system with the
manure belt drying feature. As they plan to pass their
operation to the next generation, the Van Vuurens looked
for solutions that would be cost-efficient to operate and
offer equipment longevity. Temperature ranges in the area
are from -30 F to 100 F. There have been no operational
www.WATTAgNet.com ❙ May 2018
The body heat given off by cage-housed hens
is often sufficient for maintaining adequate
temperatures and air quality in wintertime in
belt-battery housing. Cage-free housing systems give birds more room, which means less
heat is produced by the hens per cubic foot of
house space. Also, the litter or scratch area of a
cage-free house will result in the production of
more ammonia and dust than is generated in a cage house
with manure belts.
Controlling ammonia in a cage-free layer house is
generally accomplished by keeping the litter area dry
and increasing house ventilation. This increased ventilation rate coupled with less bird body heat per cubic foot
means that many cage-free layer houses will need supplemental heat in cold weather. Heat exchangers provide
the opportunity to transfer heat from exhaust air to fresh
air brought in from outside to reduce heating costs.