Toilet paper recovery from municipal wastewater and application in building sector

One of the most innovative applications for a circular economy approach is the recovery of cellulose fibres from municipal wastewater. Recovered cellulose fibres from the wastewater could bring benefits to the construction industry in terms of reducing the amount of non-renewable raw materials and increasing sustainability. Rotating belt filter was used to obtain cellulose fibre-rich sludge from real urban influent. Recovered cellulosic material reached values up to 26.59 g m when the solids removal efficiency was higher than 70%. Treated cellulosic sludge had an average of 87% content of cellulose, hemicellulose and lignin. The recovered cellulose fibres were analysed and used in mortar mix to understand their possible impact in the building sector and the effect on the properties of hydraulic lime-based mortars. Properties of fibre addition were investigated in terms of microstructure and mechanical strength. Cellulose fibres were added by mix volume up to 20%. The overall results with the maximum content of cellulose fibres indicated the improvement of mortars performance in terms of increased lightness, flexural strength and hygrometric properties.