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Salt at its best hroughout history, salt has played a pivotal role through trade routes, voyages of discovery, power struggles, religious ceremonies, agriculture, medical treatments and more. Not to mention adding taste to make the most delicious dishes in the world.
It is estimated that if all of the salt from the oceans could be spread evenly across the earth’s surface, it would form a layer the height of a 40-storey office building. If you consider that about 70% of the earth’s surface is covered with water, and 97% of that water is saline, it is clear that our planet has a lot of salt water. But where does all that salt come from? Over time, dissolved carbon dioxide from rain, in the form of carbonic acid, erodes rock and ultimately carries salts and minerals into the sea.
Concentrated brine is pumped into the crystallisation ponds for final evaporation. NaCl crystallises on the pan floors and is harvested. Just before harvesting, the brine, now called “bittern”, is pumped away. The bittern contains various unwanted chemical impurities. Salt crystals are ready for harvesting after 11 months. A harvesting machine, operated with a laser system, removes the layer of salt, which is now 150-180 mm thick, at a rate of 600 tonnes per hour. After harvesting, the crude product is upgraded through a wash process to remove impurities such as calcium, magnesium and insolubles in order to meet a wide range of client specifications. Through a process of centrifugation, excess moisture and the remains of the chemical impurities adhering to the salt crystals are removed. This results in the final salt product, of which NaCl makes up more than 99.2%.
As Africa’s largest sub-Saharan solar evaporation salt mine, the traditional core business of Walvis Bay Salt is to produce, The product is either bagged in process and market sea salt in both various pack sizes or shipped in bulk bulk and bag formats for the local to various markets internationally. The amazing colours of the and international markets. The Salt is used in the chemical industry mine processes approximately 100 produce chloride and caustic crystallisation ponds – dark to million cubic metres of seawater soda, which in turn are needed per annum to produce in excess for the production of synthetic pink, purple or red – are of 1.1 million tonnes of crude salt products such as plastic. A small caused by microorganisms annually, covering an area of more portion of the product is also refined than 5,000 hectares of land. All it such as the Dunaliella salina for human consumption. Unrefined needs is seawater, sunshine and salt is used in the agricultural sector. algae that thrive in the brine. wind – luckily in plentiful supply in the area. The company’s main markets are Southern Africa, East and West Africa, Europe and North Located at the coastal town of Walvis Bay in Namibia, America. In addition to salt, the company also produces Walvis Bay Salt was established in 1964 through oysters of exceptional quality for the export market. the evaporation of seawater. Seawater contains an approximate 3.5% solution of a mixture of various salts, The salt pan system contains a myriad of living organisms with sodium chloride (NaCl) accounting for about 2.7% and microorganisms that sustains a great number of of seawater’s salinity. The process involves the pumping wetland birds such as flamingos and waders. It has been of seawater from the open lagoon area at a rate of 240 estimated that approximately 70% of all Lesser Flamingos cubic metres per minute into a series of evaporating ponds on the Southern African continent make use of the salt with progressively decreasing surface areas. With the pans and its surroundings as a feeding ground. The area has gradual movement of the water through the pond system, been identified as one of the three most important coastal the freshwater constituent of the saline broth evaporates wetlands in Africa. Annual bird counts conducted since 1983 because of solar heat and wind, resulting in a decrease in have indicated up to 140 000 birds at a time, and more than water content and an increase in salinity. 60 species have been identified.
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