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A novel cooling system for a hot elastic plate is considered by combined utilization of magnetic field, wavy channels and ternary nanofluid. Some applications can be found in electronic cooling, material processing and convective heat transfer control. The elastic object is placed between sinusoidal wavy channels where magnetic field of different strengths is imposed. Ternary nanofluid is used as cooling medium in both channels. Cooling performance assessment is made by various values of Reynolds number (Re, between 250 and 1000), Hartmann number of different channels (Ha, between 0 and 15), amplitude (A, between 0.05 and 0.3) and wave number (N, between 1 and 4) of corrugation, and nanoparticle loading (svf between 0 and 0.03). Entropy generation analysis is also considered. Thermal performance enhancement factor for the maximum and lowest Re configurations in the rigid and elastic object cases are 1.70 and 1.65, respectively. The amount of cooling performance improvement generated by imposing magnetic field at the highest strength is 58.5% and 80% with rigid and elastic objects, respectively. The cooling performance is improved by the wavy form amplitude; however, the wave number relation is non-monotonic. When comparing the wavy channel with the flat one, the increments of thermal performance for stiff and elastic plates are 52% and 57%. Using elastic and stiff objects with nanofluid results in increases in cooling performance of 47.2% and 55.5% when compared to the use of base fluid alone. The best thermal performance is always provided by a rigid item with wavy channels. The least amount of cooling is achieved by using an elastic plate and flat channel. The best options are to increase the magnetic field strength and amplitude of the wavy channel as thermal performance improves and entropy generation drops. [ABSTRACT FROM AUTHOR]

Polyester manufacturing industries produce highly polluted effluents, containing organics, nutrients, trace metals, and 1,4-dioxane, requiring a high degree of treatment before being discharged into the water bodies. This study focused on removing complex pollutants from a diluted polyester industrial effluent (DPIE) via a cost-efficient anaerobic/aerobic combined system, with biogas recovery. The integrated pilot-scale system was composed of an up-flow anaerobic multi-staged reactor (UASR; V = 41 L) followed by an auto-aerated immobilized biomass (AIB; Vsponge = 9.54 L) unit and operated at a total organic loading rate (OLR) of 0.75 ± 0.16 g COD/L/d and pH of 7.14 ± 0.14 at 25 °C. The UASR achieved removal efficiencies of 17.82 ± 3.14% and 15.90 ± 3.08% for chemical oxygen demand (COD, total and soluble) and 15.83 ± 4.68% for total Kjeldahl nitrogen (TKN), with bio-CH4 yield of 263.24 ± 31.98 mL/g COD. Adding the AIB unit improved the overall CODtotal, CODsoluble, and TKN to 93.94 ± 2.39%, 94.84 ± 2.23%, and 75.81 ± 3.66%, respectively. The NH4-N removal efficiency was 85.66 ± 2.90% due to the oxic/nitrification condition on the sponge's outer surface. The entire system also achieved 73.26 ± 2.68%, 77.48 ± 5.74%, and 81.26 ± 6.17% removals for Fe (3.93 ± 0.95 ppm), Zn (5.92 ± 2.32 ppm), and 1,4 dioxane (2.50 ± 0.61 ppm). Moreover, the UASR-AIB maintained removal efficiencies of 76.53 ± 8.47% and 77.51 ± 7.38% for total suspended solids (TSS: 335.95 ± 42.84 mg/L) and volatile suspended solids (VSS: 263.50 ± 36.94 mg/L). Regarding the DPIE toxicity level, the EC50 value increased from 12.9 to 39.4% after UASR/AIB application. The UASR's microbial community at the genus level demonstrated that the synergistic cooperation of solubilization, hydrolysis, acidogenesis, acetogenesis, and methanogenesis was responsible for the degradation of DPIE components. [ABSTRACT FROM AUTHOR]

Purpose: A new approach was proposed to model the extraction kinetics according to the operating parameters. This approach is based on the determination of the critical time tc (a characteristic time which depends on the operating parameters). Methods: It is necessary to start by collecting the experimental values of tc from experimental kinetics using the second derivation of extraction yield. Then, a full factorial design 23 is used to model tc as function of studied factors: temperature, solid-liquid ratio and ultrasonic power. The obtained expression of tc was used in second time as the basis of the modeling of extraction kinetics. It made possible to locate the inflection point that separates the two intervals of the extraction. To assure continuity in this point, we changed variable of time for the second phase of extraction and we started fitting from the last calculated point from the first phase. Seven models were tested to fit studied kinetics. Results: A mathematical model was proposed to express tc according to the operating parameters of the studied extraction. Patricelli (composed of two exponential terms) and the exponential models showed the best fitting results for all experiments. Patricelli model fitted very well the first phase of experiments and the exponential model fitted the second phase. Conclusion: This confirms a new coupled washing/diffusion hypothesis of extraction performing in three steps: washing, first diffusion step, and second diffusion step. [ABSTRACT FROM AUTHOR]