DESALINATION, vol.164, no.1, pp.63-70, 2004 (SCI-Expanded)
Ultrafiltration (UF) studies were conducted on latex and ink rinse wastewaters to assess the potential of concentrating the wastewater and recovering the permeate for reuse and recycling purposes. The physicochemical characteristics of the ink and latex wastewater suggested that the quality of both wastewaters was strongly dependent on the rinse process. A 4-fold and 7-fold concentration of ink and latex wastewater, respectively, may be achieved depending on the initial physicochemical characteristics of the wastewater. The UF system concentrated the latex wastewater to a total solids (TS) concentration of 275 g/L (approx. 28%) and to 99 g/L (approx. 10%) for ink wastewater. The permeates had turbidities ranging from 0.13 to 0.4 NTU. However, a significant percentage of the TS remained in the permeate of the ink wastewater which may require further treatment before it can be reused. For latex wastewater, it is likely that the retentate can be reused along with the permeate for rinsing purposes. For the ink wastewater, both pore blocking and cake resistance models were able to describe the change in flux with time. However, for the latex wastewater, pore blocking seemed to describe the flux with time data better than the cake resistance models. The fouling coefficient, K, for the pore blocking model was found to be a function of the TS present in the latex wastewater.