By Isabel Siew
Reverse osmosis (RO) has become a cornerstone of water purification, desalination and industrial water reuse, but its reliance on high operating pressures comes with a significant energy cost. H2MO is seeking to challenge that model with its bio-programmable membrane reverse osmosis (BPMRO) technology, designed to deliver comparable rejection performance while operating at substantially lower pressures.
According to Guan Ong, chief executive officer of H2MO, the technology combines a bio-programmable membrane structure with a hollow-fibre configuration to increase water permeability and reduce fouling.
Engineering a more permeable membrane
The technology uses biomaterials to influence the formation of the thin-film composite layer during membrane manufacturing. Rather than remaining within the finished membrane, the biomaterials are removed during processing, leaving behind a structure with greater surface area and more channels through which water can pass.
“The final structure has a lot more leaf-like structures on the surface and greater surface area,” Ong explained. “We also have a lot more loose structures within the rejection layer itself, allowing more channels for water throughput and allowing water to flow more easily through the membrane structure.”
According to Ong, this higher permeability allows the membrane to achieve greater water throughput while requiring less pressure.
H2MO’s second innovation is its hollow-fibre configuration, which differs from the spiral-wound format commonly used in conventional RO systems. Ong said the design allows water to flow continuously through the membrane, reducing the potential for contaminants to accumulate and contributing to improved fouling resistance.
Combined with lower operating pressures, these characteristics enable the membranes to achieve higher flux and permeability while reducing the energy required for treatment.
The biomaterials used during production do not remain in the finished membrane. “After the process, it disappears,” Ong said, noting that the finished membranes contain no residual biomaterials. H2MO’s membranes have also received NSF safety certification.
Reducing the energy burden of RO
Energy efficiency is becoming increasingly important as water treatment operators contend with rising electricity costs and growing demand for power from industries such as data centres.
Ong said H2MO’s membranes maintain rejection performance comparable with conventional RO membranes, while their higher permeability reduces the pressure needed to achieve the same water throughput. “In terms of pressure, we are able to use up to about 50% less,” he said, adding that this can translate into energy savings of around 40–50% in suitable applications.
The potential impact is significant because electricity can account for around 70% of the cost of membrane filtration processes, according to Ong. Reducing the energy requirement could therefore lower both operating costs and the carbon footprint associated with water treatment.
Making use of existing pressure
One of the most significant opportunities created by ultra-low-pressure operation is the ability to make use of pressure that already exists within a water system.
H2MO’s membranes can operate across a pressure range of approximately 2–8 bar, according to Ong. This creates opportunities to use residual pressure from existing processes rather than relying entirely on additional pumping.
In a conventional RO system, the reject stream can retain significant pressure after passing through the membrane. In some industrial applications, this pressure can reach 6–10 bar.
H2MO’s approach is to recover this existing pressure and reduce it to the level required to drive water through its membrane system. “I do not need pumps because I am using existing pressure in the water lines,” Ong said.
In suitable applications, this could bring the energy requirement for the treatment stage close to zero.
The same principle could potentially be applied to lower-pressure applications. Household water systems, for example, can already operate at around 2–4 bar, creating the possibility of integrating RO without the additional pumps and components typically required to increase pressure. “We are also exploring new ways of ultra-low-energy applications that enable us to be pump-light or pumpless,” Ong said.
Supporting industrial water reuse
H2MO sees potential across industries that require large volumes of high-quality water, including electronics, semiconductors, energy, food and beverage, pharmaceuticals and petrochemicals.
As water resources become increasingly constrained, particularly in densely populated or water-stressed regions, the ability to recover and reuse existing water supplies is becoming more important.
Ong sees opportunities to treat industrial water to a quality suitable for direct reuse in production processes or power generation, helping industries reduce freshwater demand while lowering the energy burden associated with treatment. “Where there are industries that require a lot of water and good-quality water, this is where we see a role for ourselves,” he said.
Developing new applications
H2MO’s development priorities extend beyond improving the performance of its existing membranes. The company is also exploring new applications that can take advantage of the technology’s ultra-low-pressure operating range.
One potential area is emergency water supply. Conventional emergency filtration systems can remove bacteria, sediments and other particulates, but may not remove dissolved chemicals.
Ong believes low-pressure RO could make higher-quality water treatment viable in these applications. “With RO at such low-pressure operation, it is now viable,” he said, noting that the technology could potentially produce mineral-water-quality water from a wider range of sources.
At the same time, H2MO is working to further increase membrane permeability and improve fouling resistance, with the aim of delivering additional energy savings and reducing operating expenditure.
A technology platform for water reuse
H2MO’s BPM technology is not limited to RO. The company says its bio-programmable membrane platform can also be used to manufacture nanofiltration and forward osmosis membranes, broadening its potential applications across water treatment and resource recovery.
For Ong, however, commercialisation will depend not only on membrane performance but also on collaboration with companies capable of integrating the technology into real-world projects. “We position ourselves very much as a solutions provider,” he said. “We provide tools, but one thing we do not do is EPC work.”
Instead, H2MO is seeking partners to develop projects around its technology, with the company providing membrane solutions tailored to project requirements.
As water reuse expands across industrial sectors, reducing the energy intensity of treatment will become increasingly important. By combining high-permeability membranes, hollow-fibre architecture and ultra-low-pressure operation, H2MO is seeking to expand the range of applications in which RO can be deployed economically.
The broader opportunity may lie in using pressure and infrastructure that already exist rather than continually adding energy-intensive equipment. If successful, this approach could make RO a more flexible tool for industrial water recovery, reuse and decentralised treatment.
All images courtesy of H2MO.
