Frequently Asked Questions about FlowMixer

Watreco’s FlowMixer will improve the water quality in rivers, lakes, ponds, fountains, waste water treatment plants and fish farms by aerating and circulating the water but only using 50% of the energy compared to traditional systems.

It is scalable from small ponds in golf courses and city environments to large lakes, rivers, fish farms or waste water treatment plants. 

FlowMixer can be used in rivers, ponds, lakes, fountains, fish farms, waste water treatment plants etc… in any water that can be pumped As it also circulates the water it can also replace propeller aerators and similar systems.

The system is scalable. Bigger FlowMixer units can be used and/or sequenced to generate the water flow and air intake required. 

The FlowMixer units are powered by submersible pumps to create the water flow needed. In a case study comparing FlowMixer with propeller agitators, the FlowMixer skid was powered by 2 Pedrollo pumps at 7.5kW each, 15kW in total. 

This setup enabled the FlowMixer to circulate and aerate around 2,000m3 of water per hour, pulling in the same amount of air (2000m3). This means the required entry input needed to draw in 1m3 of air through the FlowMixer application is 0.0075kW.

Tests have shown that around 20 times more water is involved than what is pumped through the system. For example, if every second 100 litres of water are flowing through the FlowMixer, some 2000 litres of water is circulated at the same time.

FlowMixer is installed in skids or as individual units. The installation can be added to any water body as long as there is a minimal depth of 0.5m. 

FlowMixer units can easily be maintained and cleaned by removing the top cap that is crewed on. 

Warranty for the FlowMixer system is 5 years. 

FlowMixer units are 3D printed out of PA2200, which is a type of Nylon. The material is touch and wear resistant, can resist up to 110 deg C. It’s also been tested against concentrated Ozone for 24 hours without any problems.

Yes, larger particles and “long” particles i.e. treads can clog the FlowMixer. However, this is a problem for the pump as well. Eventually the pump will set the “standard” for the system. The FlowMix unit can be taken apart for cleaning.

Fouling and scaling will not occur inside due to the high flow and as long it is possible to pump the water. 

In this picture, the unit was tested inside a fat separation tank in a wastewater treatment plant. After 2 months the unit was taken up and looked as it does in the left picture. However, the inside was completely clean and the canals had not clogged.

Normally, the units can run for very long time, up to a year before maintenance is needed.

In comparison, a membrane based bubbler must change the membrane twice a year (typically) where you need to buy new membranes, as the rubber in the membrane clogs and is aged. Considering the amount of diffusers at the bottom (approx. 9 per m2) this is very costly and time consuming.

 Yes, as larger particles and “long” particles i.e. treads can clog the FlowMixer. 

A large particle is defined as > 5 mm in diameter or longer than 20 mm.

Yes, the centralized pump can be utilized to pump the water through the FlowMix units, if the pump can feed the needed number of units. The air compressor is not needed, but can eventually compensate for any lack of flow from the pump. However, the FlowMixer unit can be run on compressed air as well. This means that the air is used two times. First in order to pump the water, then for aerating.

In general, the FlowMixer will produce finer bubbles and circulation at the same time. As is gives finer bubbles it can put more oxygen into the water for a lower energy cost.

The system gives freedom to use wind powered units where we do not need to go over electricity, i.e. no energy cost at all. This is favourable in remote areas.

No, the tank doesn’t need to be empty. However, you might need to use a diver if the tank is too deep. The units can very easily be removed due to the Kamlock connector for the water and air feed. When the unit is on shore it can be divided and cleaned if necessary. 

The easiest way is to buoy the air tube so the inlet is above water. Then, if the buoy is connected to the FlowMix unit (with pump) with a rope, the whole system can be lifted to the surface. Lifting the unit in the air hose is not recommended.

The air bubbles introduced to the water are less than 2mm, and adjustable using a valve.

We have observed bubbles down to 0,1 mm in diameter in the smallest bubbles. In some cases (extreme but possible) the water looks like “inverted fog” as shown here. 

During these conditions the bubbles create foam not unlike the “foam head” on beer. The interesting thing is that the very fine bubbles lifts out different substances from the water that later can be skimmed off.

The trade off is not circulation but the amount of air that is sucked in to the water. However, the finer bubbles compensate for this as we achieve a better SOTR with finer bubbles, up to a “certain” degree. The “best” air would the bubbles we do not see. They have dissolved completely.

Watreco’s FlowMixer is manufactured and quality controlled in Sweden.