Salt: The Facts
Salt, or sodium chloride has a chemical formula of NaCI, with each single gram of salt usually containing around 40 per cent sodium and 60 per cent chloride.
It has been used for many years, so long in fact, that it has been in use long before recorded history.
Naturally salt occurs in seawater when an area of water becomes enclosed and the sun causes the water to evaporate.
This natural rock salt is used to de-ice our roads in the winter weather, but has to be processed in a different environment to achieve the salt that many of us enjoy on our fish and chips.
Most of the salts used in over 14,000 products today come from ancient underground salt deposits and are actively mined in Cleveland, County Antrim and Winsford in Cheshire.
However there are many hundreds of salt beds across the world, with no real fear that stock piles will ever run out, certainly not in our lifetime.
The Mining Process – Rock Salt
Rock salt mines vary in depth from 100 metres to over one mile in depth and within them are networks of pathways formed from previous extractions, which act as roads. There are approximately 140 miles of tunnels in our rock salt mines in the UK, which is almost as long as the M5 motorway.
There are two techniques used to mine rock salt in the UK. These are cut and blast mining and continuous mining.
Cut and blast mining is done by cutting a slot at the base of the rock face using a machine called the undercutter, with a jib carrying a series of tungsten-carbide picks. Using an electro-hydraulic rotary drill, a series of carefully sited holes are drilled. The rock is crushed into pieces about the size of a football, using a feeder-breaker. It is then passed along a conveyor belt, where it is crushed even furtherand sieved to ensure they are just the right size to de-ice our roads.
Continuous mining is different is and produces smaller rocks using a boring machine, similar to a pneumatic drill.
Its head rotates carrying a tungsten-carbide tip, which bores into the salt.
Because the lumps are smaller they are transferred directly to a crushing and screening plant, rather than being crushed by a feeder-breaker.
About Salt: The Facts: The Environment
Members of The Salt Association actively seek to minimise the environmental impact of their manufacturing, storage and distribution operations and are constantly looking at ways to help the environment.
Salt is not damaging to our environment and does not require registration under the Environmental Protection Act Integrated Pollution and Control Regulations.
Our industry is continuously regulated through a number of European Directives who regulate food safety and Environmental performance.