Fluorescent lamp recycling

From Wikipedia, the free encyclopedia
Jump to: navigation, search

Fluorescent lamp recycling is the recovery of the materials of a spent fluorescent lamp for the manufacture of new products. Glass tubing can be turned into new glass articles, brass and aluminium in end caps can be reused, the internal coating can be reprocessed for use in paint pigments, and the mercury contained in the lamp can be reclaimed and used in new lamps.[1] In the United States, about 620 million fluorescent lamps are discarded annually; proper recycling of a lamp prevents emission of mercury into the environment, and is required by most states for commercial facilities.[2] The primary advantage of recycling is diversion of mercury from landfill sites; the actual scrap value of the materials salvaged from a discarded lamp is insufficient to offset the cost of recycling.[3]

Mercury in lamps[edit]

The amount of mercury in a fluorescent lamp varies from 3 to 46 mg, depending on lamp size and age.[4] Newer lamps contain less mercury and the 3–4 mg versions are sold as low-mercury types. A typical 2006-era 4 ft (122 cm) T-12 fluorescent lamp (i.e. F34T12) contains about 5 milligrams of mercury.[5] In early 2007, the National Electrical Manufacturers Association in the US announced that "Under the voluntary commitment, effective April 15, 2007, participating manufacturers will cap the total mercury content in CFLs under 25 watts at 5 milligrams (mg) per unit. CFLs that use 25 to 40 watts of electricity will have total mercury content capped at 6 mg per unit."[6]

Only a few tenths of a milligram of mercury are required to maintain the vapor, but lamps must include more mercury to compensate for the part of mercury absorbed by internal parts of the lamp and no longer available to maintain the arc. Manufacturing processes have been improved to reduce the handling of liquid mercury during manufacture and improve accuracy of mercury dosing.[7]:194

Mercury-free discharge lamps have considerably lower production of visible light, about half; mercury remains an essential component of fluorescent lamps. [7]:192

A broken fluorescent tube will release its mercury content. Safe cleanup of broken fluorescent bulbs differs from cleanup of conventional broken glass or incandescent bulbs.[how?] 99% of the mercury is typically contained in the phosphor, especially on lamps that are near their end of life.[8]

Phosphors[edit]

Lamps made up to the 1940s used toxic beryllium compounds, which were implicated in the deaths of factory workers.[9]:Chapter 7[10] Today however, it is very unlikely that one would encounter any such lamps.[11]

Formerly, toxic materials such as beryllium, arsenic, cadmium, and thallium were used in phosphor manufacture. Modern halophosphate phosphors resemble the chemistry of tooth enamel. The rare-earth doped phosphors are not known to be harmful.[7]:195

Mercury containment[edit]

When a fluorescent tube is discarded, the main concern is the mercury, which is an important toxic pollutant. One way to avoid releasing mercury into the environment is to combine it with sulfur to form mercury sulfide, which will prevent vapor release and is insoluble in water. One advantage of sulfur is its low cost. The reaction is shown with the equation:

Hg + S → HgS

The easiest way to combine sulfur and mercury is to cover a group of fluorescent tubes with sulfur dust (sometimes called "flowers of sulfur") and to break the tubes; when the glass fragments are put into a bag to continue with the reaction, the mercury will combine with sulfur without any other action. The glass can be recycled where an appropriate facility exists. A quantity of 25 kilograms (55 lb) of dust sulfur is enough for 1000 tubes.[citation needed]

Disposal methods[edit]

The disposal of phosphor and mercury toxins from spent tubes can be an environmental hazard. Governmental regulations in many areas require special disposal of fluorescent lamps separate from general and household wastes. For large commercial or industrial users of fluorescent lights, recycling services are available in many nations, and may be required by regulation. In some areas, recycling is also available to consumers.

Spent fluorescent lamps are typically packaged prior to transport to a recycling facility in one of three ways: boxed for bulk pickup, by using a prepaid lamp recycling box, or crushed onsite before pickup. A fluorescent lamp crusher can attach directly to a disposal drum and isolate the dust and mercury vapor.[citation needed] In some states, drum-top crushers and end-user crushing of lamps are not allowed.[why?]Minnesota Department of Health Drum Top Bulb Crusher Demonstration Disposal methods are regulated at both the state and federal level.

Proper recycling of fluorescent lamps can reduce risk of human exposure to mercury. Companies that recycle spent fluorescent lamps include Air Cycle Corporation; Midwest Lamp Recycling, Inc.; Mercury Technologies of Minnesota, Inc.; USA Lamp & Ballast Recycling, Inc; Waste Management; and Veolia.

Supplier Responsibility[edit]

The concept of Supplier Responsibility, with respect to lamp recycling, considers the involvement of Lighting and Electrical Distributors and large big box retailers (i.e: those who sell new mercury containing lighting equipment to large end users and contractors) in a reverse supply chain. This would see the warehouse space of wholesalers and large retailers, currently deployed to store the new equipment, be reorganized to allow space for waste lighting equipment. This model has been deployed for other types of waste, particularly glass bottles, where in many jurisdictions around the world a deposit systems drives the empty glass bottles back to a space where they can be consolidated and organized. Once organized the cost of moving them to a processing or recycling facility can be executed far more efficiently.

Under Supplier Responsibility, suppliers of mercury containing lighting equipment would be required or at least urged to accept the return of waste lighting equipment from their customers or other generators. The premise of the model is that organizing and consolidating waste makes transport and final processing more efficient and that the organizing and consolidating should be done by those who have experience handling the product when it is new. The condition of a new piece of lighting equipment and an old piece of lighting equipment is irrelevant from a logistics and material handling perspective. The only thing that has changed is that the lamps internal electrical infrastructure can no longer function, it is no longer in original packaging and its outer glass jacket may be dirty.

Supplier Responsibility is an excellent complement to existing Extended Producer Responsibility (EPR) and Product Stewardship programs. Suppliers are a key stakeholder in the effort to recycle because they have ready access to the contractors and commercial properties which generate the vast majority of waste mercury containing lighting equipment. Suppliers can aid, inform and reinforce the generators' commitment to recycling in a multitude of ways:

First, by creating awareness. Suppliers can inform future generators that the equipment they are purchasing contains mercury and needs to be returned so that it can be sent to a mercury management facility for processing. Second, by combining the sale of new equipment with the collection of old equipment, real estate and vehicle assets can be deployed far more efficiently. Trucks that would normally return to base empty can be filled with the waste lighting equipment generated from previous deliveries. Real estate assets can be redesigned to allow for consolidation of old equipment as well as the sale of new equipment. And finally, by adding a highly specialized group of businesses and workers who are very familiar with the handling and shipping of the product new, you add a lot of knowledge and increase the potential of innovation. There are examples of supplier innovation in the lamp recycling realm. US patent 9,061,820, - a simple low cost, reusable cardboard container, specifically designed for the storage and safe shipping of waste fluorescent tubes, was invented in 2010 by Michael Colligan, the owner of a small lighting distribution company.

There are barriers to Supplier participation in the lamp recycling world. Some of these barriers involve resistance from the Suppliers themselves who do not wish to organize and consolidate the waste equipment or deploy scarce human resources in the effort. However most of the barriers involve legacy regulations by various levels of government which make the collection and transport of waste lighting equipment illegal unless carriers have special licenses or permits. Many jurisdictions have exempted certain streams of waste such as lighting equipment, thermometers and thermostats but the complexity and wording of the new regulations is often unclear. Furthermore, the propagation of antiquated rules and the fear mongering of those who carry permits and licenses have caused the adoption of the Supplier Responsibility model to stumble.

It is understood that a lot of lighting equipment contains mercury and that mercury is a potential human toxin. However, it contains mercury when it is new as well as when it is old. And if it is dangerous to handle when it is spent it is no less dangerous to handle it when it is new. Fluorescent and HID lamps are broken all the time in installation, storage and shipping and there are no known cases of human mercury contamination in lighting suppliers, contractors or end users so the argument is one of classification rather than an imminent threat. Most human mercury contamination occurs from the consumption of contaminated fish and the use of mercury in amateur gold mining operations in developing nations not from the management of new or spent lighting equipment.

If jurisdictions wish to increase the proper end of life management of waste mercury containing lighting equipment then they should clearly declassify fluorescent, compact fluorescent and high intensity discharge lamps from hazardous waste to some other category. Local environmental protection agencies should set up agencies which permit Suppliers to register as consolidators or large volume handlers and monitor their activities to insure the material goes to a mercury management facility An example of this is the Recycling Council of Ontario’s Take Back the Light Program.

References[edit]

  1. ^ Fluorescent Lamp Stewardship Initiative, Alberta Environment, 2000, ISBN 0-7785-1730-6
  2. ^ Release of Mercury from Broken Fluorescent Bulbs, State of New Jersey Division of Science Research and Technology, Feb. 2004, pg. 1
  3. ^ Alberta Environment
  4. ^ Page 183 of http://www.chem.unep.ch/MERCURY/Toolkit/UNEP-final-pilot-draft-toolkit-Dec05.pdf
  5. ^ "Lighting Design Lab Articles - Mercury in Fluorescent Lamps". Archived from the original on May 14, 2011. 
  6. ^ "NEMA Voluntary Commitment on Mercury in CFLs". [dead link]
  7. ^ a b c Kane, Raymond; Sell, Heinz [editors] (2001). Revolution in lamps: a chronicle of 50 years of progress (2nd ed.). Lilburn, GA: Fairmont Press. ISBN 0-88173-378-4. 
  8. ^ Floyd, et al. (2002), quoted on page 184 of Toolkit for identification and quantification of mercury releases (PDF) Archived March 4, 2009 at the Wayback Machine
  9. ^ Rosner, David; Markowitz, Gerald [editors] (1987). Dying for work: workers' safety and health in twentieth-century America ([1. Dr]. ed.). Bloomington: Indiana University Press. ISBN 0-253-31825-4. 
  10. ^ Beryllium toxicity and fluorescent lamp manufacture, retrieved June 7, 2008 Archived October 3, 2009 at the Wayback Machine
  11. ^ General Electric Fluorescent Lamps TP 111R, Dec. 1978, says on pg. 23 that since 1949 GE lamps used relatively inert phosphates found to be safe in ordinary handling of either the intact or broken lamp.

External links[edit]