Poorly-slaked lime can have a major negative impact on lime consumption and the operating cost at an end-user’s site. The amount of lime used in the process is determined by a combination of slaking parameters. The optimisation of the slaking process will help drive operating costs down and also reduce CO2 emissions. By Roman Stoiber, STT Enviro Corp Systems & Solutions, Canada.
When the slaking of lime (ie, the conversion to calcium hydroxide – Ca(OH)2) takes place on site it is often carried out by operators who don’t have specialised slaking training. Optimising the slaking step can result in significant savings in lime consumption. Studies have shown that anywhere between 10-40 per cent can be saved in chemical consumption by ensuring lime slaking is carried out under optimum slaking conditions. This is true whether the process application is water treatment, exhaust gas scrubbing, mining beneficiation or downstream chemical processing.
