CSTR

Continuously Stirred Tank Reactor

The CSTR (Continuously Stirred Tank Reactor) is a cleverly engineered floating ‘tank’ designed to replicate the same function of a land-based mechanical tank.
The CSTR serves as:

1. An equalization tank
2. An incubation tank
3. A microbe selector tank

Horizontal-flowing surface water piles up at a floating boom that encircles the unit to create a vertical downward driving force. The down-flowing water ricochets off the sludge directly under the boom and follows a curvilinear diagonal path back to the Blue Frog™ (BF) inlet. As the diagonal-flowing water returns to the BF, a countercurrent is induced below the BF in the donut shaped annulus defined by the bottom and the diagonal-flowing water.

The produced current is aerobic; the countercurrent is anaerobic. Both currents bring nutrients and microbes into gentle-but-intimate contact. The population of the slow-growing anaerobes triples because nutrient availability is no longer rate limiting; the population of the aerobes does not change because oxygen availability controls the rate of aerobe growth.