Optimisation of Carbonation Reactor Design Using Multiphysics Models for Precipitated Calcium Carbonate PCC Production

Abstract

Temperature distributions in the carbonation reactor with an inner diameter of 4.23m and overall length of 7m is numerically modelled. This is motivated by the need to lower overall capital and operating costs, and to optimise the carbonation process performance, simultaneously. In this paper, computational simulations are used to design an industrial scale carbonation reactor 89.72m 3 consisting of an external cooling jacket. Several parameters are varied including reactor's geometry (6 shapes), wall thickness (100, 200, and 300mm), cooling jacket temperature (15, 25, and 35ºC), and material type. These parameters are varied interchangeably to compare temperature probe plots at a point probe (1.5,0) located closer to the cooling jacket region. Simulations in COMSOL ® Multiphysics 5.2a show that partial Carbon Steel AISI 4340 jackets with a 100mm distance, between vessel wall and outside wall of jacket, while operating at ambient temperature range of 20-25ºc, can achieve the required operating temperature i.e. 50±5ºC. Then, the precipitation process of the calcium carbonate (PCC) is maximised. This result in decreased bare materials' capital costs by 95.87% and 97.39% compared to Nickel and Titanium, respectively. The need for cooling the water for the jacket is eliminated, while operating costs are lowered by 25-50% per 10ºC. A simplified experimental setup is proposed to demonstrate the coupling of COMSOL ® simulations with experimental work can be a reliable and an effective method to evaluate the carbonation reactor model design.