Metal: Difference between revisions

Revision as of 11:58, 6 December 2019

Overview

A metal is defined as 'a material of various opaque, fusible, ductile, and typically lustrous properties that are good conductors of electricity and heat, form cations by loss of electrons, and yield basic oxides and hydroxides'^[1].

The term metal can capture a wide range of different categories/types within the waste and resources sector, but the macro split tends to be into Ferrous Metal, Non-Ferrous Metal, and Mixed Metal (which is then subsequently sorted into various categories for subsequent recycling) - the broad term normally used for waste metals is scrap metal in the UK.

Scrap Metal Grades (examples)

Whilst the macro split is into essentially three categories, scrap metal dealers and recycling business trade in the wider commodity markets which have a global influence. Grades of non-ferrous and ferrous scrap metal might include, for example:

Mixed Brass Scrap
Mixed Alloy Cuttings
HE9:Clean
Household Cables
18/8 Stainless Steel Solids
13% Chrome Iron
70/30 Cupronickel
Dry Bright Wire
Heavy Copper
Lead Batteries
Grade 1 Old Steel (No1 5ft)
Grade 5C Loose Light Steel Scrap
Grade 10 Light Cast Iron

Local Authority Descriptions

Local authorities collect materials and describe them as required by WasteDataFlow, which is based primarily on the use or origin of the metal, for example cans and fire extinguishes. The headers following are these categories with a listing of which local authorities collect a significant tonnage of these types of materials. Whereas local authorities separately identify large WEEE items such as domestic fridges, the scrap metal industry tends to classify, recycle and trade based on the metal type from these appliances.

Scrap Metal Recycling

Recycling of metals can include the following processes:

Collection, weighing, sorting and distribution of metals: dealing with a wide range of suppliers, including engineering industries; small traders, such as plumbers or vehicle dismantlers; local authority collection sites; and householders disposing of domestic appliances.
Shearing – reducing the size of large pieces of metal by cutting
Baling/compacting – to improve ease of handling and transportation
Shredding – reducing feedstock to fist-sized lumps; and separating metals from other materials using magnets and air classification methods. A large shredder can process a car in less than ten seconds.
Media separation – further separation of any remaining non ferrous metals using liquid density and hand or mechanical sorting methods
International metals trading – moving metals around the world^[2].

Macro Tonnages

The most recent information published by DEFRA ^[3] ^[4]is summarized in the pie charts below, with 2,060,580 tonnes of ferrous, 478,855 tonnes of non-ferrous and 3,965,881 tonnes of mixed metallic wastes generated in the UK in 2016 and is part of the broader figures reported in UK Waste Tonnage:

File:Metallic Wastes Pie Chart.png

Metallic Wastes - Tonnage Reported as Generated by DEFRA in 2016

The recording of tonnage from the following headers by local authorities in WasteDataFlow is aggregated into the household figures, as the tonnage of metals that might be extracted from Comingled Recyclate that are sorted at a MRF, although these tonnages are not reported by the local authorities in WasteDataFlow]] as segregated metals unless the MRF provides information back to them