.SIMULATION AND OPTIMIZATION OF ZEOLITE PRODUCTION SCHEMES FOR WATER TREATMENT

Abstract

Zeolites are hydrated aluminosilicates with uniform pore size distribution. Zeolites exist naturally in sedimentary deposits. Due to their special structure, characteristics and properties they are used in a wide variety of applications including water treatment, adsorption, catalysts, and molecular sieves. Continuous efforts are exerted to develop the systems production as the annual demand for zeolite exceeds 5 million tons worldwide. This work is concerned with the assessment, on technical and economic criteria, of the optional schemes for production of zeolite A, which is used in water treatment in general and as a detergent builder in particular. The ultimate aim is the identification of the optimum scheme and its technical requirements and economic indicators. On the basis of thorough review of the published literature, optional processes for the production of zeolite A have been identified. The principal systems considered include the production of zeolite A using pure materials or natural materials (clays) with or without pretreatment. According to the current local consumption, the production capacity has been assumed to be 150 tpy, as a base case. However, considering that commercial production lines for zeolites have capacities in the order of magnitude of thousands, capacities in the range 150 tpy to 10000 tpy have been technically and economically investigated. The optional processes have been simulated using HYSYS flowsheeting software, which has been adopted to the purpose. Accordingly, detailed material and energy balance, process flow sheets, analysis of unit operations and processes have been obtained. Engineering development has been then undertaken for equipment selection and sizing of all the major equipment for the investigated cases at varying production capacities .. Economic analysis has been conducted to identify the capital and production costs, revenues, and profitability as expressed by the Simple Rate of Return. Further, sensitivity analysis has been conducted to study the effect of probable variations in economic parameters optimistically and pessimistically. Further, the minimum