Pumps as Turbines (BFTs) can be considered a technical and economical solution to control pressures in Water Distribution Networks (WDNs) as a replacement for Pressure Reducing Valves (PRVs). Their use requires an accurate understanding of the operation under various hydraulic conditions in an RDA (off-design). Otherwise, machine efficiency is reduced, making it impossible to regulate pressure and recover little energy. This study presents a methodology that details pressure regulation in a municipal network using BFTs. The evaluation of pressures in the RDA is done for three scenarios (C1 - PRVs operating 24h; C2 - PAT operating 18h and PRV operating 6h; and C3 - PATs operating 24h). Pump selection and off-design operation is performed using two models from the literature. The machines are simulated at varying speeds to replace the valves. The leakage reduction in the three scenarios is estimated. In all scenarios,
there was effective pressure control; in C2 and C3, the PATs regulate the WDN pressure as if it were a PRV and according to current Brazilian legislation. In C2, the best efficiencies (0.674 to 0.675) and power (4.27 kW) occur when flow rates are high and speeds are low (2,500 rpm at 11am and 3,000 rpm at 6pm). The C3 behaved similarly, producing an average power output of 3.70 kW. Thus, the outlet pressure of the pump and throughout the network are regulated, reducing a significant amount of leakage. With this, in C2 the BFT recovers 28,038.00 kWh/year and in C3 32,392.00 kWh/year. Therefore, C3 presented the best results, first from the hydraulic point of view, then from the energy point of view.
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