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This investigation reports the use of agrowaste pomegranate peels as an economical source for the production of fluorescent carbon dots (C-dots) and their potential application as an antimicrobial agent. The carbon dots were prepared through low-temperature carbonization at 200°C for 120 min. The obtained C-dots were found to be small in size and exhibited blue luminescence at 350 nm. Further, the synthesized C-dots were characterized with the help of analytical instruments such as DLS, UV-visible, FT-IR, TEM, and fluorescence spectrophotometer. Antimicrobial activity of the C-dot PP was estimated by the agar diffusion method and MIC. S. aureus and K. pneumoniae are showing susceptibility towards C-dot PP when compared to the standard and showing a moderate activity against P. aeruginosa and resistance towards E. coli. The obtained C dot PPs were found to be around 5-9 nm in size confirmed from DLS analysis and supported by TEM. The synthesized C-dots were investigated to understand their microbial efficiency against pathogens and found to have antimicrobial efficiency. These results suggest that pomegranate peels are a potential source of carbon dots with antimicrobial efficiency.

The quality of a treated effluent changes when there is a sudden variation in the influent flow to the wastewater treatment plant during dry, rain, and storm weather conditions. In this study, various influent flow conditions in an activated sludge process are considered that affect the sensitivity of effluent variables such as chemical oxygen demand (COD), biological oxygen demand (BOD), nitrate nitrogen (SNO), ammonical nitrogen (SNH), and total nitrogen (TN) with respect to varying internal recycle flow rate (Qa), sludge recycle flow rate (Qr), sludge wastage flow rate (Qw) and oxygen transfer rate co-efficient of aerobic tanks (KLa(3,4,5)). The analysis has been carried out based on benchmark simulation model no.1 (BSM 1) plant layout which comprises of two models namely activated sludge model no.1 (ASM 1) and simple one dimensional (Simple 1-D) Takacs model. Based on the present analysis, it is observed that the changes in influent flow rate have larger impact on the effluent variables. This variation can be subdued by introducing additional tanks to smoothen the perturbations or using internal recycle rate from the fifth tank in order to maintain the flow around the optimal influent flow rate. The sludge wastage rate has a greater impact on all effluent variables except nitrogenous variables during maximum flow conditions.

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In this paper, benchmark simulation model no.1 (BSM1) of an activated sludge process is used to evaluate various control strategies. Control configurations such as feedback control and feed-forward plus feedback (FF-FB) control are applied and compared with respect to effluent discharge requirements under specified constraints and operating costs. Feed-forward control is incorporated in the PI control configuration for preventing the influent loading disturbance affecting the process. No case studies of BSM1 model have been reported in the literature for the Indian wastewater. In this work, the dynamic simulation of an activated sludge process is performed using the data collected from the sewage treatment plant, located in India. The influent load data are collected during the dry weather period. The influent fractionation is carried out using the activated sludge model no.1 (ASM1). The results of the dynamic simulation indicate that FF-FB control of the activated sludge process is more effective than feedback control in meeting the constraints, especially effluent ammonia concentration which is considered as very important. From the comparison of performance evaluation criteria, it is observed that FF-FB control has achieved almost the same operating costs as with feedback control.