In the early 1990s, during the period of a lull following the commissioning of the Indian Tokamak “ADITYA” at the Institute for Plasma Research (IPR), the idea of converting our rich experimental knowledge base created over two decades of producing and manipulating plasmas into industrial applications appeared attractive. Moreover, plasma science seemed to offer unique and novel opportunities in high-energy-density and high value-added material processing.
Plasma processing exploits plasma as an industrial tool. Plasma can respond to external electromagnetic energy fields and transport energy. Setting up internal self-consistent electric and magnetic fields enhances fluid properties, resulting in collective effects like flows, waves, instabilities and self-organization. Each species may have independent energy distribution, not necessarily in equilibrium with other species. The internal energy is composed of thermal, electric, magnetic and radiation fields, whose relative magnitudes allow the plasma state to exist in vast, multi-dimensional parameter space. Properties like high chemical reactivity, microscopic electric fields, sheaths, radiation and particle flux mediate plasma processing. Plasma-based manufacturing integrates the plasma-material interaction phenomena with the manufacturing process. The technology adds value to conventional materials and makes new materials and processing techniques possible by exploiting the characteristics of both the equilibrium and non-equilibrium plasmas.
The Plasma Processing Programme at IPR had some unique features not encountered in basic research. The necessity for it to be relevant to industry, the fact that it can make or lose money in its commercial exploitation, the contractor-client relationship with industries etc., are some examples. It was the first time in India that a research institute ventured into a commercial application programme. So, the business plan evolved and matured along with our learning curve. The programme had to be industry-driven to make it agile and responsive to rapid changes and focused on a few thrust areas where the immediate impact would be possible. Financial self-reliance was a goal from the beginning.
The first foray was into plasma nitriding because of the interest shown by several industries. Nitriding is a process in which Nitrogen is incorporated into the steel matrix to increase hardness. The prototype was a cold wall furnace with only plasma heating. We added heat shields to minimize heat loss and increase thermal efficiency and uniformity. We obtain the auxiliary heated hot-wall reactor by actively heating the vacuum vessel with a heating element. We also added automation and computer control to build state-of-the-art systems during this time.
Plasma Nitriding became the first technology to be transferred to industry. In addition to this, we set up a job shop to do nitriding of high-value components like plastic dyes etc., on a commercial basis. Work on many other applications like thermal plasma processing of zircon sands, anodic vacuum arcs, plasma ion implantation etc., followed this. The zircon dissociation was our first foray into thermal plasmas and plasma torches.
In 1997 we moved our activities to the industrial area in Gandhinagar. The primary reasons for this were the relative inaccessibility of IPR being an institution under the Department of Atomic Energy and our concern that the grand settings would give an impression to the customers that the plasma technology would be equally exotic. As a result, the Facilitation Centre for Industrial Plasma Technologies (FCIPT) came up in a rented building in the industrial area of Gandhinagar to act as a bridge with industry. We consolidated all technology development, demonstration, incubation, and commercialization activities. FCIPT had a multi-disciplinary group of physicists, material scientists, chemists and engineers and infrastructure for process and instrumentation development for plasma technologies.
FCIPT is a path breaker in India in converting physics-based research into commercially and societally valuable devices and processes. We transferred technologies to industries by supplying complete process plants manufactured by FCIPT. We can:
· nitride industrial components like precision moulds and hydro turbine parts, reaching defined hardness and case depth values.
· synthesize large-area optical quality reflective and anti-reflective coatings using Plasma Enhanced Chemical Vapour Deposition.
· deposit super-hydrophobic fluorocarbon films on surfaces with expanding plasma jets, making them slide without friction.
· create high enthalpy flows to test material properties at high temperatures and ignite coal fired furnaces.
· densify, spherodize or segregate ceramics in in-flight high-temperature plasma jet reactors and produce aerosols and Nano particles.
· texture Angora wool in atmospheric pressure cold plasma to enhance the spinnability of the yarn.
· destroy medical waste with a 95% volume reduction and undetectable levels of dioxins.
· create cold plasma streams to induce changes in biological materials with applications in medicine and agriculture
We developed an atmospheric pressure dielectric barrier discharge system to produce large-area Helium free cold plasma. As a result, continuous steams of Angora wool fibre can be introduced and retrieved after treatment. A technology demonstration unit for Angora wool farmers has been functioning at Kulu in collaboration with the Wool Research Board and the Government of Himachal Pradesh.
Another development relevant to the brass ware industry in India is a Technology Demonstration Plasma Polymerization reactor in which plasma dissociates a monomer containing silicon to form thin silicon dioxide coatings on finished brass ware, providing a tarnish-proof lifetime protective coating. The brass ware manufacturers in Moradabad are using the unit for the final finishing treatment of their products.
We developed a plasma treatment process of tyre valve stems made of brass to release Zinc, which interacts with Sulphur in vulcanized rubber to form brass-rubber solid bonds. This durable rubber-brass bond has a high resistance to dynamic and thermal ageing, typical in its use in automobile and truck tyres. We scaled up the process to treat more than 600 pieces per batch, necessary for industrial-scale exploitation by a manufacturer of these valves. In addition, this process is environmentally friendly compared to the conventional treatment, which uses chemicals and acids for the procedure.
In September 2000, I got an opportunity to participate in the third conference on “Physics and Industrial Development: Bridging the Gap” at Durban, South Africa. The meeting was the third of a series of biennial conferences initiated by the Commission on Physics and Development (C13) of the International Union of Pure and Applied Physics (IUPAP) to empower physicists in developing countries to foster physics-technology bonds in developing countries. I described the IPR initiative in establishing links with the Indian industry for developing and commercializing advanced plasma-based industrial technologies. There were many participants from developing countries who found this initiative very inspiring.
Plasma processing has transcended conventional material processing applications into waste destruction, environmental remediation, water purification, flue gas treatment etc. It is emerging as an enabling tool with a broad spectrum of applications relevant to modern industrial society.
Even after two decades, the spirit of innovation thrives in FCIPT. A cold plasma system to treat high-density polyethylene (HDPE) has been developed for Central Institute of Plastic Engineering and Technology, Ahmedabad for inline processing of HDPE. Inline plasma treatment facility to treat synthetic textiles with plasma at the rate of 30 to 40 metres per minute has been supplied to Man-Made Textile Research Association (MANTRA) for innovation in the textile manufacturing process. We have developed an atmospheric pressure plasma system for food processing with continuous feeding of the food material. Nano-powder production technology has been transferred to private industry. A plasma pyrolysis / Gasification system to dispose of the liquid solvent waste and generate useful fuel gas has been installed at CSIR-CSMCRI, Bhavnagar.
On 30th October 2021, FCIPT became one of the ‘Atal Incubation Centres’ as a part of the ‘Startup-India’ mission. As an AIC, it will support the nucleation and growth of startups based on Plasma Based Technologies in India and utilize the multi-disciplinary team of scientists, academics, students and industry representatives. Its location in the GIDC industrial zone is an added advantage.