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The housing of the membrane component is an Inconel 625 case joined to the membrane component by means of a custom-developed glass-ceramic sealant that exhibited a remarkable thermo-chemical compatibility both with metal and ceramic, despite the appearance of chemical strain in LSCF at high temperature. The multi-disciplinary approach followed in this work is suitable to be adapted to other module concepts based on membrane components with different dimensions, layouts or materials.The livestock industry negatively impacts the environment by producing high organic and mineral loaded manure and wastewater. On the contrary, manure is also considered as the major focal point of resource recovery. The microfiltration (MF) process in manure treatment is well known for being the least complex and highly energy efficient. However, the major fraction of the dissolve nutrients easily bypasses the MF membranes. In this research work, we reported the efficiency of using MF-nanofiltration (NF) treatment train in a dead-end filtration system for the treatment of raw manure. The objectives were to produce nutrient rich separate streams in reduced volumes and a particle and pathogen-free product water. MF removed TSS above 98% and the COD and phosphorus (P) retention were noticed above 60 and 80%, respectively, within a reduced MF concentrate volume, which accounted for 40% of the initial feed volume. The NF of MF permeate by NF270 showed most promising results by concentrating overall 50 and 70% of the total nitrogen (TN) and potassium (K) within a reduced NF concentrate volume, which accounted for 30% of the initial MF feed volume. Finally, the MF-NF treatment train of raw pig manure could produce a particle-free product water that can be reused in farms to wash barns, to irrigate nearby cultures, or can be applied to specific fields based on the demand.The fouling/wetting of hydrophobic membrane caused by organic substances with low-surface energy substantially limits the development of the membrane distillation (MD) process. The sulfate radical (SO4·-)-based advanced oxidation process (AOP) has been a promising technology to degrade organics in wastewater treatment, and peroxydisulfate (PDS) could be efficiently activated by heat. Thus, a hybrid process of MD-AOP via PDS activated by a hot feed was hypothesized to mitigate membrane fouling/wetting. Experiments dealing with sodium dodecyl sulfate (SDS) containing a salty solution via two commercial membranes (PVDF and PTFE) were performed, and varying membrane wetting extents in the coupling process were discussed at different PDS concentrations and feed temperatures. Our results demonstrated permeate flux decline and a rise in conductivity due to membrane wetting by SDS, which was efficiently alleviated in the hybrid process rather than the standalone MD process. Moreover, such a mitigation was enhanced by a higher PDS concentration up to 5 mM and higher feed temperature. In addition, qualitative characterization on membrane coupons wetted by SDS was successfully performed using electrochemical impedance spectroscopy (EIS). The EIS results implied both types of hydrophobic membranes were protected from losing their hydrophobicity in the presence of PDS activation, agreeing with our initial hypothesis. This work could provide insight into future fouling/wetting control strategies for hydrophobic membranes and facilitate the development of an MD process.Propylene is industrially produced in a mixture with propane and generally separated from the mixture via distillation. However, because distillation is an energy-consuming process, a more efficient separation process should be developed to mitigate both carbon dioxide (CO2) emissions and production costs. In this study, a two-stage membrane-separation process was designed, and its CO2 emission and production costs were evaluated. The separation processes were designed to minimize energy consumption using different membrane combinations (two recently developed membranes each). To evaluate the separation processes using various membrane combinations, two indicators, i.e., CO2 emissions and total annual costs (TACs), were estimated based on the process simulation (Pro/II, version 10.1.1) results, including energy consumptions, operation expenditure, and capital expenditure. These results were compared to the distillation processes as benchmarks, and the advantages of the membrane-separation process were discussed. In the comparison, carbon taxes were implemented for assessing these two independent indicators as a single indicator, i.e., TAC with carbon tax. Furthermore, using the same scheme, model membranes were also employed in the two-stage membrane-separation process as case studies of technological forecasts.In this study, membrane fabrication was achieved by two different methods (i) self-assembly and (ii) physical blending of TiO2 in PES membrane for humic acid filtration. The TiO2 nanoparticles were self-assembled by using TBT as the precursor and pluronic F127 as triblock copolymers around the membrane pores. This was achieved by manipulating the hydrolysis and condensation reaction of TBT precursors during the non-solvent induced phase separation (NIPS) process. On the other hand, the TiO2 was physically blended as a comparison to the previous method. The characteristic of the membrane was analysed to explore the possibility of enhancing the membrane antifouling mechanism and the membrane flux. The membrane morphology, pore size, porosity, and contact angle were characterised. Both methods proved to be able to enhance the antifouling properties and flux performance. The HA rejection increased up to 95% with membrane flux 55.40 kg m-2 h-1. The rejection rate was not significantly improved for either method. However, the antifouling characteristic for the self-assembly TiO2/PES membrane was better than the physically blended membrane. This was found to be due to the high surface hydrophilicity of the MM membrane, which repelled the hydrophobic HA and consequently blocked the HA adsorption onto the surface.Fouling tends to cause a significant increase in hydraulic resistance, decreased permeate flux, or increased transmembrane pressure (TMP) when a process is operated under constant TMP or constant flux conditions. To control membrane fouling and maintain sustainable operation, the concept of critical flux has been discussed by several researchers. Various fouling mechanisms, such as macromolecule adsorption, pore plugging, or cake build-up, as well as hydrodynamic conditions, for example aeration, can take place at the membrane surface. This study aimed to investigate the effects of mixed liquor suspended solid (MLSS) concentration and air bubble flow rate (ABFR) on the critical flux and fouling behavior, when treating refinery-produced wastewater. To determine the critical flux values, the experimental flux-steps were the following (1) the filtration began with a 30 min step duration at a low flux (10 to 20 L/m2h); (2) at the end of this step (after 30 min), the permeate flux was increased, (3) this step was affected the membrane performance, based on the critical flux and fouling behavior.The ocean thermal energy conversion (OTEC) is a potential substitute for traditional power plants in tropical islands and coastal regions. However, the OTEC power generation cycle has low thermal efficiency and the integrated utilization is imperative, in which an OTEC coupled with seawater desalination is the most attractive option. Membrane distillation (MD) has distinct advantages making itself a competitive process for seawater desalination, especially the feature that the drained warm seawater from the OTEC power plant can be recycled, improving the integrated output of the OTEC system. In this study, an innovative OTEC system coupling a power generation sub-cycle (PGC) and a water production sub-cycle (WPC) was proposed, composed of the upstream organic Rankine cycle and the downstream membrane distillation modules. The mass, energy and exergy balance of the individual equipment, the sub-cycles and the whole system were performed by constructing the corresponding balance models. The thermal dynamic parameters were calculated, and the performance of power generation and water production was predicted. The results showed that by coupling with the MD desalination, the thermal efficiency of the OTEC system can be greatly improved from 2.19% to 25.38% while the exergy efficiency changed little. For a 100 kW OTEC power generation cycle, the water production rate approached 58.874 t/d. In addition, the economic analysis based on the electricity and water sale was carried out, and the profit can be improved by extra water production, especially in the Hawaii and Rainbow Beach by nearly 20%.There is a consistent demand for developing highly sensitive, stable, cost-effective, and easy-to-fabricate creatinine sensors as creatinine is a reliable indicator of kidney and muscle-related disorders. Herein, we reported a highly sensitive and selective non-enzymatic electrochemical creatinine sensor via modifying poly(3,4 ethylenedioxythiophene) polystyrene sulfonate (PEDOTPSS) coated indium tin oxide (ITO) substrate by zeolitic imidazolate framework-8 nanoparticles (ZIF-8 NPs). The topography, crystallinity, and composition of the sensing electrode were characterized by field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The peroxidase-like activity of ZIF-8 nanoparticles enabled it to detect creatinine forming a zinc-creatinine composite. The electrochemical behavior and sensing performance were evaluated by amperometric and impedimetric analysis. The sensor obtained a sufficiently low limit of detection (LOD) of 30 µM in a clinically acceptable linear range (0.05 mM-2.5 mM). The interference study demonstrated high selectivity of the sensor for creatinine concerning other similar biomolecules. The sensing performance of the creatinine sensor was verified in the actual human serum, which showed excellent recovery rates. Hence, the magnificent performance of ZIF-8 based non-enzymatic creatinine sensor validated it as a responsible entity for other complicated renal markers detection.The purpose of this study is to establish a practical simulation model based on mass balance, mass transport equations and equilibrium equation between gas and liquid phases across a porous membrane in membrane contactor process in order to predict the separation behavior by the gassing process of gas mixture in membrane contactor. The established simulation model was verified by comparison between the simulated values and real process values in the separation of CH4/CO2 mixture, showing an excellent agreement between them. The parameter R-value in the model, which is a kind of the permeability of permeant across porous membrane, has been determined by fitting a numerical solution of the model equation to the experimental data to obtain a practical value of the parameter. A parametric study on the gassing process of N2/CO2 mixture in membrane contactor was made with the help of the practical simulation model to investigate the effects of operation parameters on separation performance and to characterize the separation behavior of membrane contactor process.

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