Satyajai Mayor, Managing Director, Permionics Membranes, discusses the intricacies of membrane technology. He reiterates the importance of water harvesting, reducing pollution in water bodies and reducing indiscriminate building in order to tackle the water resources problem.
Tell us more about membrane technology, its applications and relevance for India.
Membrane technology is a separation process using a semi-permeable membrane to sieve out the impurities from the solution/solute. Its applications are vast and across the filtration spectrum. Any industry that uses water will need membranes either for water desalination to produce process water, to recycle waste water, or to separate/purify/recover products and impurities from solutions and also to purify and extract maximum utility from process water. This technology is not new to the world of water. Membranes have been applied for water decontamination and purification since the early 60´s. It was an Indian-born Canadian, Dr Sourirajan, who demonstrated that a semi-permeable membrane can extract pure water from a salt solution when a pressure greater than the osmotic pressure of the feed is applied to the salt solution. Most of the desalination plants in the Middle East use Reverse Osmosis membrane technology to desalinate seawater. I remember that way back in 1980, our founder, Satyapal Mayor, who developed the RO membrane from theory and commercialised the technology in India, demonstrated to the Government of Gujarat how they could alleviate the scarcity of drinking water in drought-hit regions of the state. Simultaneously at that time, he deployed membranes for use in a special application of concentration and purification of papain enzyme which was probably the first time membranes were used for such an application. This led to various other interventions in areas like pharmaceuticals, biotech, infrastructure and other such industries. On the relevance of membranes in water management - yes, they are now an integral part of any tertiary treatment plant, be it surface water, sewage water or industrial waste water.
Is membrane technology enough to deal with the threat of contaminated groundwater?
Membrane technology is not a standalone process and needs upstream and downstream processes to work in tandem. For example, if we need to remove fluoride or arsenic from water using membranes, we still have to deal with the reject stream from a membrane which is more contaminated than the feed. So a combination of coagulation and filtration is more suited with membranes in tandem where they provide the filtration media for such applications where a solid precipitate is generated while rendering the water free from the contaminant.
Do you have any installations at all for any state or municipal governments?
The answer to the first part is yes, we do have installations of membrane systems for townships and villages. Our business is more related to membrane separation where water and waste water recycling is one of the applications. About increasing our installations for urban water treatment, we surely are looking at that market, especially now when we have expanded our membrane manufacturing facilities and yes, we have the capabilities and capacities and also the designation of the first and only membrane manufacturer in India. Our facilities provide integral solutions and our knowledge base is broad spectrum. The new membrane manufacturing facility is producing UF, NF and RO membranes where all three processes can be used depending on the type of water and end use. The use of our indigenous membranes will really and truly make the whole project a real ´Make in India´ model.
Do your systems work independently or should they be considered as only a single part of a sequence of different technologies?
In most industrial applications, the membranes/membrane systems can be used on a standalone basis, especially in treating process solutions.
However in waste water and water treatment applications, proper pre-treatment and removal of turbidity and suspended solids is essential for the membrane to work for reasonable lengths of time.
Pre-treatment is the key to successful operation of a membrane plant. We have developed high COD tolerant and high turbidity intake spiral wound elements that work more efficiently than disk/tube and other configurations as well. But upstream primary and secondary treatment processes are essential to reduce contaminants that are settleable and biodegradable. These conventional processes have low operating costs and its pointless using a more expensive method when a proven and cost-effective method can do that job.
How much of your revenues are derived from industrial applications?
Around 80 per cent of our revenues are derived from industrial applications. The market for our membranes for replacements is also growing at a fast pace. As mentioned above, our COD tolerant membranes are leading the battle for reducing recycling costs and making membranes more robust in this challenging application.
Where do you see the market for your products in the coming years?
The next five years are dedicated to water recycling and reuse. Revenues will be generated from these applications. And as said earlier, we see a large chunk shared by membrane replacement. Also, as your readers may be aware, water is perhaps going to become one of the most precious commodities in the next few years.
What are the challenges that you are facing?
We face one major challenge: competition from players inexperienced in the business of waste water recycling with little experience in membranes. They end up designing a system that may work on borewell water, but certainly collapse when run on waste water. This ends up giving a bad name to the technology.
What are your views on how the country can tackle its water resources problem?
Water harvesting, reducing pollution in water bodies and reducing indiscriminate building, are the main drivers to augment water resources. If you see the rain map of the country, it is scattered but overall in excess. So I am sure there is scope and hope.
Is enough emphasis placed currently on water conservation and sustainable water practices?
Yes, I think the new generation is more aware and proactive. But given the nature of the challenge facing us, I do feel there is a much greater need for educating and guiding people as to how water is used.