how much blood is recycled through the kidneys everyday
The average human has about 1.0 to 1.5 gallons of blood. The kidneys continually filter this throughout the day, all the blood being filtered about once every 45 minutes or so. The BBC Body page puts the figure at 150 liters a day which is around 40 US (33 UK) gallons. Other data source puts the figure at about 180 liters a day, which is 48 US ( 40 UK) gallons.