Technology - Finnvoda Reverse Osmosis

”The best way of helping customers is designing something so good that there's no need for comparisons.”

Esko Aulanko, Finnvoda CEO

Our technology
and
patented solutions

ICR
(Integrated Concentrate Recirculation)

up to 80% and above reverse osmosis recovery rate

NERO-ICR (Integrated Concentrate Recirculation) – ICR is our patented breakthrough innovation on enhancing RO-recovery rate. ICR increases the recovery of close to any membrane or RO-system to up to 80% even at tap pressures without compromising the membrane lifetime, or actually, without compromising anything.

The ICR technology for increasing reverse osmosis recovery rate has been utilized in our products for roughly 10 years. By far the highest recovery rate reverse osmosis systems currently on the market.

See table below on the right for comparisons between ICR, and traditional methods for increasing reverse osmosis recovery rate.

Easily fitted to small and large RO-systems
Retrofittable to existing and in-use systems
Can be applied to almost any membrane or membrane housing
Minimal or even negative costs per system
Low material costs
Functions even on tap pressures (min 3 bar)

The ICR technology is currently available for licensing

Do you represent a RO-system or membrane manufacturer? Want your products to reach even 80-90% recovery rates?

Contact
+358 44 230 4501
esa.aalto@finnvoda.fi

Technology licensing availability

China
Europe
India
United States
Finland
Sweden
Various other Global / Local levels - Inquire

Method for increasing recovery

Membrane lifetime uncompromised

Is low-cost and easy to implement

Water quality uncompromised

Can easily reach even up to 80% recovery

ICR

Restricting reject flow

Mixing RO-water with UF-water

Textbook recirculation (HP-Pump input)

What’s the big deal?

Traditional RO-systems function at typical recovery rate of 20-25%. They require 4 to 5 liters of feed water to make just a single liter of drinkable water. The rest goes down the drain, literally. A low recovery rate increases the filter and membrane replacement rate while at the same time demanding more from the raw water pump due to a higher total feed water volume. Hundreds of millions of liters of perfectly usable water is wasted due to low recovery rate systems.

As of now, many countries are introducing new strict regulations and even bans on water wasting low recovery reverse osmosis systems. The most recent example is from India, where the NGT (National Green Tribunal) is driving various regulations and bans on low recovery RO-systems. Similiar movement can be seen in China, and various other countries, where tap water is not usually drinkable, as well.

Increasing reverse osmosis recovery rate

Recovery rate increase done correctly – What are the limiting factors?

Available Pressure

The first limiting factor is the available pressure. The needed pressure depends on the raw water TDS and the recovery rate. Pressure must exceed the osmotic pressure of the feed flow, and the osmotic pressure depends on the feed flow water. If the pressure is lower than the osmotic pressure of the concentrate, the system will not work. What needs to be understood, is that the only concentrate that matters is the one on the membrane surface.

Concentration polarization

Concentration polarization is caused by pure water penetrating the membrane. At the membranes’ surface, the concentration increases and grows larger than the concentration in the feed channel on average. In a properly functioning system, a typical CPF (Concentration Polarization Factor) could be around 1.2, while systems utilizing reject flow restrictors could face a CPF of up to 5. Polarization intensifies throughout the membrane and is at it’s highest at the end, this is due to reduced feed flow and increased concentration. The effect is intensified on low grade membranes.

Scaling and fouling

Scaling means the build up of saturated matter on the membrane surface, while fouling describes microbes and other organic growth clogging the membrane. Fouling is often divided into biofouling and caking. Caking describes for example oxidized iron which clog the membrane. While scaling can be decreased by applying anti-scaling agents, the best way to deal with scaling and fouling is again, to increase the flow velocity.

Membrane lifetime

The question is, how much membrane lifetime is sufficient for your system and for your customers. Membrane life most often ends into scaling and fouling, and most traditional methods on increasing reverse osmosis recovery rate leads to not increasing feed flow velocity, therefore reducing membrane life. If you want to improve the recovery rate, you must increase the feed flow velocity at the same time.

What about permeate quality? Doesn’t it suffer with recirculation?

Yes and no. Permate quality degradation is caused mostly by concentration build-up on the membranes’ surface, and is circumvented by again, increasing feed flow velocity. With ICR increasing feed flow velocity, at large recovery rates, the permate quality can be even better than systems with no recirculation.

Conclusion?

The recovery rate of a reverse osmosis system essentially restricted by 2 factors, the available pressure and feed flow velocity.

So how to increase feed flow velocity?

There are two ways of increasing the feed flow velocity. One is tampering with the membrane geometry and flow direction. The thickness of the feed spacer directly effects the feed flow velocity. As you decrease the thickness of the feed spacer, fouling and caking is intensified. More thin the channel, more caking and fouling.

The other is recirculation.

80% recovery rate without recirculation

80% recovery rate with recirculation

NERO-IDS
(Intelligent Distribution System)

NERO-IDS (Intelligent Distribution System) – IDS is our patented method of delivering purified water from the system to a water network. The traditional costly, malfunction-prone distribution pump is replaced by [Redacted], which continuously delivers purified water to the network while consuming no energy. NERO-IDS provides fully automatic water distribution in the exact same manner as a dedicated distribution pump. As an added bonus, distribution is completely silent.

Zero energy usage for distribution
System no longer requires electronics and logic for automatic distribution
Enables 100% storage tank utilization, which in turn reduces size for the system
Reduces system noise levels by a large margin

The NERO-IDS technology is currently available for licensing

Do you represent a RO-system manufacturer? Want your products to deliver water silently, with zero energy and reduce your manufacturing costs?