Garbage disposal recycling

Fittings, Fixtures And Services 3(1+2)

Lesson 15 : Garbage and solid waste disposal system

Garbage disposal recycling

The practice of recycling solid waste is an ancient one. Metal implements were melted down and recast in prehistoric times. Today, recyclable materials are recovered from municipal refuse by a number of methods, including shredding, magnetic separation of metals, air classification that separates light and heavy fractions, screening, and washing.

Another method of recovery is the wet pulping process: Incoming refuse is mixed with water and ground into slurry in the wet pulper, which resembles a large kitchen disposal unit. Larger pieces of metal and other non-pulpable materials are pulled out by a magnetic device before the slurry from the pulper is loaded into a centrifuge called a liquid cyclone. Here the heavier noncombustible, such as glass, metals, onto a glass- and metal –recovery system; other, lighter materials go to a paper-fiber-recovery system.

The final residue is either incinerated or used as a landfill. Increasingly, municipalities and private refuse- collection organizations are requiring those who generate solid wastes to keep bottles, cans, newspapers, cardboards and other recyclable items separate from other waste.

Last modified: Wednesday, 15 February 2012, 4:44 AM