CFL (CFL)

CFL stands for compact fluorescent lamp, a screw-base or pin-base lighting product that produces visible light by passing an electric arc through mercury vapour in a sealed glass tube; the ultraviolet emission excites a phosphor coating on the inner glass wall, which fluoresces in the visible spectrum. Every CFL therefore contains a small but legally significant quantity of mercury — typically 2-5 milligrams per lamp, with older Indian-manufactured CFLs sometimes reaching 8-10 mg.

Why CFLs are hazardous e-waste: Mercury is a potent neurotoxin and a globally listed substance under the Minamata Convention, which India ratified in 2018. When a CFL is broken, roughly 17-40% of the contained mercury vaporises immediately and the remainder leaches into soil and water if the broken lamp enters a municipal landfill. India's E-Waste (Management) Rules, 2022, list fluorescent lamps and CFLs in Schedule I as e-waste requiring channelised collection, separate from mixed municipal solid waste.

Collection and processing: Producers placing CFLs in the Indian market carry an EPR obligation to collect a notified percentage of historical sales each year and route them to a CPCB-authorised mercury-lamp recycler. The processing technology of choice is the end-cut and air-push method, which separates the metal end caps, the inert glass tube, and the mercury-bearing phosphor powder. The phosphor is then thermally distilled in a vacuum retort at 400-600 degC; the mercury vapour is condensed and recovered as a high-purity liquid for industrial reuse, while the residual phosphor is stabilised with sulphur or cement and landfilled at a TSDF.

Trade-offs and current status: CFL volumes in Indian e-waste are now declining sharply as LED lamps have captured more than 90% of the new-lamp market since 2018. However, the installed base of CFLs in homes and offices is still substantial, and dedicated mercury-lamp processing capacity in India remains under-built — only a handful of authorised recyclers nationwide can handle mercury-containing lamps to CPCB standards. Mixing a broken CFL into ordinary glass cullet contaminates the entire batch and is a frequent failure mode at unauthorised informal collection points.