1. Call yourLocal Grainair InternationalAgentinSouthAfrica
Alex Kockon+27761698370 or email kock.ah@gmail.com
Webwww.grainair.com.au

2. These photoswere takenrecentlyinSouthAfrica.This
20,000 ton bunkerof White Maize has beendestroyedbymoisture andisnow unusuable as a food source
and alsoas seedforfuture crops.
Grainair International usesproventechnologyandaerationmethodologiestostopthiskindof damage from
happening.We are soconfidentinourmethodsthatwe guarantee lessthan.25% grain lossineveryfacility
we manage.Askus howby contactingeitherAlex KockinSouthAfricaorWayne Paddisonforinformation on
othercountries.
Moisture Migration
How Moisture Migrates
Dry grain isan effectivethermal insulator andthe outer
sectionsof a grainbulkchange temperature fasterthan
the lessexposedgraininthe centre of the SiloorBunker.
The temperature differenceswithinthe grainmasscause
air currentsto move fromthe warm to the coldgrain. The
directionof aircurrentswithinthe grainmassdependson
whetherthe grainiscoolingasthe outdoortemperature
dropsor warmingasthe outdoortemperature increasesin
the springand summer.
Because airholdsmore moisture whenwarmthanwhen
cold,the connectedairpicksup moisture fromthe warm
grain.Whenthe air movesthroughcoolergrain,itcools
down,andits relative humidityincreasestoa pointat
whichmoisture istransferredfromthe airtothe grain.If
the change in temperature islarge enough,waterwill
condense onthe coldgrain.In the autumnand winter,the
coldestgrainisnear the binwall andtop surface,andthe
warm grainis inthe centre of the Bunkeror Silo.
Moisture-ladenwarmairrises,passesthroughthe cold
surface grain,and depositsmoisture.Airmovesdownnear
the wall to replace the warmair risingfromthe warm grainin the centre,thusmaintainingthe convection
air pattern. In the springandsummer,the convectionairmovement isnormallyreversed fromthatwhen
the grain iscooler.The coolestgrainisin the centre of the grainmass andthe warmestnearthe wallsand
the top surface.Asthe warm air risesnearthe walls,itisreplacedwithcoolerairfromthe grain inthe centre
of the grainmass.As the warm air fromthe binover space isdrawn downwardandcontacts the centre
grain,it iscooled,itsrelative humidityincreases,andmoistureistransferredtothe coldgrain.The rate of
moisture transferis usually slowerduringwarmupthanwhenthe grainiscoolinginthe spring.
Grainair International
Webwww.grainair.com.au www.grainair.com.br
Skype wayne.paddison1
Email Wayne Paddison - wayne@grainair.com.au
Phone Alex Kock +27761698370
Wayne Paddison+61 459436758