MODELAÇÃO DO DESEMPENHO OPERACIONAL DA DESIDRATAÇÃO DE LAMAS FECAIS COM RECURSO A MODELAÇÃO: Estudo de caso da cidade de Chimoio, Moçambique

Calibration and validation of the mass water balance mathematical model used in the drying bed dewatering process involved successive simulations, adjusting parameters and initial conditions based on experimental measurements. The aim of the work was to calibrate and validate the simulation model for the dewatering of fecal sludge in drying beds. For implementation and analysis, EXCEL software was used, which facilitated both the implementation of the model and the visualization of data through graphs. The modeling made it possible to predict the behavior of the moisture content (TH), the thickness of the sludge layers and the mass of water drained during the drying cycle. The simulation revealed that the beds performed differently, with LS04 showing the highest drainage efficiency, followed by LS04 line and LS03. The comparison between the model and experimental results indicated major differences, especially in moisture content, where the model overestimated drainage efficiency. For LS03, the reduction in TH predicted by the model was only 9.9%, while the experiment indicated a reduction of 51%. These discrepancies can be attributed to factors such as variable environmental conditions and the heterogeneity of the sludge. The simulation also indicated an overestimation in the mass of water drained and the final thickness of the sludge layer, suggesting that the model needs to be adjusted to better consider dynamic and environmental conditions. The modelling proved effective for predicting drainage time and initial moisture content, but improvements are needed to optimize the accuracy of the predictions of the dewatering process.