Produção de ureia: avaliação técnica e econômica

Abstract

The demand for food has grown every year due to the great population growth and due to the scarcity of nutrients in soils of certain regions, the search for solutions to these problems makes the fertilizers more and more requested due to their capacity to supply to the soil the nutrients for its better development. This demand for fertilizers results in the need to build new industries or to modify existing industries in order to increase their productive capacities, both the implementation of a new industry and the modification of existing ones require high costs, which are the capital and operating costs. There is a classification of capital cost estimates that allows estimating how much it would cost to invest in the construction of a new plant, as well as in the modification of factories already in operation. These estimates can be made from estimates of order of magnitude to the most detailed estimates, each involving their degree of precision and effort. In the present work will be approached the estimates of the order of magnitude, as well as the estimation study, in order to estimate in the order of ± 30%, the cost to invest in a factory of urea production, and also to say if it is economically viable or not such investment. In this work, the once-through urea process will be approached because it is a less complex process and requires less equipment. The main variables in the urea production process are: Temperature, pressure and the ammonia molar ratio for carbon dioxide (〖 NH〗_3:〖CO〗_2). In order to simulate this process, the CHEMCAD simulator was used, which required the feeding of two components (biuret and ammonium carbamate), which were fed to the simulator after its thermodynamic properties were determined using the contribution methods of group of Joback and Reid and indeterminate coefficients. After the simulation it was possible to obtain 77.70% by mass of urea in the final product, for a conversion of 95% in equilibrium, thus producing 336,715.3461 ton / year.