In agriculture, the human urine could have been used as a natural fertilizer, although there are some problems with the direct utilization, such as the presence of micropollutants in urine, odour and storage of large volume of urine. Therefore, nutrients, such as nitrogen, can be recovered from urine. Continuous flow laboratory membrane reactor was built to investigate nitrogen recovery from wastewater and from human urine. Membrane gas separation method has not been investigated for ammonia recovery from human urine yet. Nitrogen as ammonia gas was recovered in acid using Zeus Aeos™ ePTFE gas-permeable hydrophobic membrane. Acid flux, operating pH, hydraulic retention time and effective membrane surface were experimentally determined. The aim of this work was to verify wastewater experiments in professional flowsheet environment, rigorously modelled with ChemCAD and optimized by dynamic programming optimization method: the membrane separation. Such nitrogen recovery membrane separation has not been published in this professional flowsheet environment yet. The objective function of the process is the ammonia harvesting efficiency. Eighty-five percentage ammonia harvesting efficiency can be reached with 60 membrane surface area/reactor volume ratio, at 35 °C feed temperature with 350 L/m²h acid and in 8 h’ hydraulic retention time. It can be stated that this separation method is based on physical phenomena without any biological factors. The focus for nitrogen treatment in a wastewater treatment plant is removal instead of recovery. It can be determined that this system is capable for the nitrogen recovery from wastewater, and it can reduce the ammonia content of human urine too.

In the separation industry the extractive heterogeneous-azeotropic distillation (EHAD) is a new and powerful innovation, that is capable of making the separation of highly non-ideal mixtures feasible and economical. In the last years there has been much attention paid to the separation of the minimum boiling homogeneous azeotropes. Although maximum boiling azeotropes are fewer in numbers than the minimum boiling ones but their separation is more complicated but it could be solved with the EHAD, too. Since EHAD is not limited to the separation of minimum boiling azeotropes, the separation of the maximum boiling azeotropes is studied in this work. Our work is motivated by industrial problems because there are such maximum boiling azeotropes in the liquid wastes of the fine chemical industry. The separation of highly non-ideal Water–Acetone–Chloroform–Methanol and Water–Ethyl Acetate–Chloroform–Ethanol quaternary mixtures are investigated and optimized in professional flowsheet simulator environment. Total Annual Costs are also determined. The purity requirement is 99.5 m/m% for Chloroform and the bottom product should be as clear as possible in water so that less liquid organic waste has to be incinerated. It is also an important merit of the EHAD that the chemicals in the distillate can be usually reused supporting sustainability. Different solutions for the separations supplemented with heat integration are examined. On the basis of the computer simulations and the experimental verification it can be concluded, the first time on the literature, that the separation efficiency of EHAD is superior also for the separation of the maximum boiling azeotrope mixtures.