Thermally stable nanofiltration membranes were used to recover hot water from rinsing effluents from acid and reactive dyeing operations. Two types of flat-sheet membranes, MPF-34 (MWCO 200) and MPF-36 (MWCO 1000), were tested at 60degreesC and 10 bar. Experiments carried out with the made-up feeds containing acid dye and acetic acid showed that both membranes were able to retain more than 99% of dye. MPF-36 suffered from substantial flux decline due to the dye and acid in the feeds but still provided higher fluxes than MPF-34. Furthermore, reactive dye rejection of MPF-36 was acceptable, ranging from 97 to 99.5%, while the fluxes, 105-140 1/m(2).h, were exceptionally high. MPF-36 was then further tested with the wastewater from industrial processes. The membrane could recover hot water by removing more than 98% of acid dye and 90% of reactive dyes. Despite severe fouling by acid dye, the membrane was still able to provide 40-50 1/m(2).h of permeate fluxes. For the reactive dye rinsing effluents, remarkably high fluxes of 120-150 1/m(2).h were obtained. Chemical cleaning of the used membrane with 0.2% wt. HNO3 and subsequently 0.5% wt. NaOH recovered 80-100% of the flux.