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Effluent application rates

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Use these templates below to help you calculate the distance an irrigator needs to travel per hour, the length of time a spray cannon can be positioned in one place, and the distance an effluent wagon needs to travel per hour.

Travelling irrigators

To calculate the distance an irrigator needs to travel (in metres) per hour:


output volume in litres per hour°  		  
desired depth of applied effluent in millimetres*    
spray swath width in metres       =  
      metres per hour
° If you know your output volume as cubic metres (m³), multiply this value by 1000 to give litres per hour.
* The maximum depth for application is 25 mm at one time.

Stationary 'spray' cannons

To calculate the length of time a spray head can be postitioned in any one place, three simple calculations have to be made:


1.    Determine the area covered by the spray head:
     x    =  
  radius of spray
circle in metres		              Pi area covered by the spray head in square metres

2.    Determine the quantity of effluent required to cover the area to the desired depth :

desired depth of applied effluent 
in millimetres* 		    x    =  
    area covered by the spray head in square metres quantity of effluent required in cubic metres

* The maximum depth for application is 25 mm at any one time.

3.    Determine the time the spray head can stay in one position:

quantity of effluent required in cubic metres		  
 x 
  =  
pump capacity in cubic metres 
per hour 		       minutes number of minutes the spray head can stay in any one position

Slurry tankers / effluent wagons

To calculate the distance an irrigator needs to travel (in metres) per hour:


volume of the tanker in litres		  
desired depth of applied effluent in millimetres*  
spray swath width in metres     =  
  metres to travel to empty each load
* The maximum depth for application is 25 mm at any one time