Dampier Salt and CAUPL have quality assurance certification under the International Standard ISO9001. The specialist operations people work to ensure that the salt is low in impurities and consistent in quality.
Each operation operates an advanced laboratory for quality control purposes with processes which continually monitor product quality. This is particularly important during the movement of through the pond and crystalliser systems.
Maintenance of the salt pavement in the crystallisers is essential to quality control so that salt is not contaminated.
In the concentrating stage chemists monitor the process to ensure that impurities such as calcium, magnesium and potassium salts don't begin to contaminate the crystalline sodium chloride. This assessment is done in the on site quality control laboratories.
The salt washing process immediately after harvesting of the salt from the crystallisers ensures a high level of salt quality as it minimises the impurity levels and eventual moisture content. The design of the wash plant and location of the salt stockpiles have an important bearing on the quality of the end product.
When deposited on the wet salt stockpile after washing, the moisture content is approximately five percent, which decreases below three percent due to natural drainage.
Salt Typical Chemical Analysis
|Sodium Chloride||(NaCl)||96.50 - 97.50%|
|Moisture||(H20)||1.80 - 2.80%|
|Calcium||(Ca)||0.03 - 0.05%|
|Magnesium||(Mg)||0.02 - 0.03%|
|Sulphate||(SO4)||0.10 - 0.15%|
|Potassium||(K)||0.01 - 0.02%|
|Insolubles||0.01 - 0.03%|
On a dry basis, the typical Sodium Chloride content is between 99.70 and 99.80 per cent.