How many times have you walked past the urinals at a metro station, or any other railway station, and grimaced or covered your nose due to the terrible odour? As reported by the New Indian Express, three odourless urinals, which convert urine into biofertilizer, have been set up at the Miyapur Metro Station, on an experimental basis. The total cost for setting up these three urinals was Rs 3 lakh. Others, at Kukatpally, JNTU and Rasoolpura Metro stations have been operational as well. Now, the Hyderabad Metro Rail (HMRL) authorities, are planning to install this facility at the other stations in the city. A process is in place that separates the water and breaks down the ammonia and urea components of urine. The urine is converted into safe water, which is directed to a soak pit through a channel. This odourless water can be used for plants. The urine is collected in an anaerobic digester, where, in the absence of air, anaerobic microbes degrade the urine, reduce stickiness and dissolve the solids. The urine then enters the activated carbon filter, followed by a biofilter. The ammoniacal nitrogen in the system is broken by a microbial strain, in which ammonia and nitrogen are se...