Branch
Report:
18th June 2005 - Site Visit
The branch annual site visit took place on the 18th May when 15
members visited Tarmac’s Port Talbot granulation and processing operation
and Civil & Marines ground granulated blast furnace slag manufacturing
plant both within Corus Steelworks at Port Talbot.
David McClelland area operations manager and Nigel Baker unit manager
explained the core activities of Tarmac’s Port Talbot works, which is the
re-processing of blast furnace slag which is undertaken by two separate
activities. The primary activity is the granulated slag process where the
granulation plant is supplied by molten slag produced direct from the
blast furnaces. The molten slag is met by water at high pressure and
volume (8 – 10 tonnes of water for 1 tonne of molten slag). On contact
the slag immediately vitrifies and it is the water ripping the slag apart
that gives it its sand like appearance.
The other activity that is undertaken is air-cooled slag digging &
processing. This is where the molten slag is skimmed off the iron and is
directed into four quenching pools adjacent to the blast furnaces. The
molten slag beds are treated with water until they are suitably cooled &
can be safely removed. Water is applied to the finished slag pool and the
thermal shock that it creates fragmentises the slag. The slag is
transported to a surge pile for weathering for a pre-determined time,
prior to the processing for sale. The slag is processed using a complete
mobile crushing unit comprising a 300tph impact crusher plus pre & post
screening machines. Single size chippings are produced for general
aggregate, asphalt aggregate and surface dressing as well as Rock Wool
fibre.
The visit continued to the Civil & Marine ground granulated blast furnace
slag manufacturing plant on the wharf in the steel works, where Martin
Johnson, John Doolan & Barrie Forrester took small groups around the plant
explaining the production process and the particular properties of the
product. The importance of the wharf facilities was highlighted along
with the capacity of the storage silo’s. Some interesting questions were
posed by the members to the Civil & Marine guides, which were all very
well answered. The thoroughly informative visit was rounded off by a
buffet in the Heronstone Hotel. The branch would like to thank David &
Nigel for very informative visit and also Anthony Morgan director of
Tarmac Western for organising the visit. The branch would also like to
thank Martin, John & Barrie for their time and allowing us around the
plant.
