Leveraging on innovation to combat COVID-19 pandemic, Assam’s Numaligarh Refinery Ltd (NRL) engineers and technical staff have developed a prototype for ‘Auto Sanitizer Tunnel’ with the objective of ensuring proper sanitising of its employees and contract workmen working in the refinery.
The design conceived by Nihar Prasad Sharma, DGM (Instrumentation), was implemented in-house by instrumentation department at its workshop with assistance of other maintenance groups utilizing mostly refurbished components sourced within the refinery.
The unit works on optoelectronic principle to automatically discharge a controlled mist of sanitizing liquid as a person walks-in through the tunnel.
Utilizing compressed air that is readily available in the refinery, the sanitizing liquid is atomized to generate a fine mist, avoiding requirement of heavy duty pump; thereby minimizing the wastage of scarce liquid disinfectant as well as regulating over exposure to the liquid to achieve safety levels.
The frame of the unit has been made from waste cable trays, the canopy from aluminum while the optoelectronic components and controller module are repaired faulty spares.
The spray nozzles have been taken from agricultural pesticide spraying hand pumps used in the locality.
The disinfectant liquid – Sodium Hypochlorite of 0.4 per cent concentration – has been sourced from NRL’s Effluent Treatment Plant and appropriately diluted to about 40 times and the compressed dry air further produces fine mist to restrict the liquid exposure within safe minimum levels.
NRL proposes to use the auto sanitizer tunnel for its plants within the refinery and other locations of the company, an NRL release informed on April 12.