Energy generation from bioelectrochemical techniques: Concepts, reactor configurations and modeling approaches.

The process industries play a significant role in boosting the economy of any nation. However, poor management in several industries has been posing worrisome threats to an environment that was previously immaculate. As a result, the untreated waste and wastewater discarded by many industries contain abundant organic matter and other toxic chemicals. It is more likely that they disrupt the proper functioning of the water bodies by perturbing the sustenance of many species of flora and fauna occupying the different trophic levels. The simultaneous threats to human health and the environment, as well as the global energy problem, have encouraged a number of nations to work on the development of renewable energy sources. Hence, bioelectrochemical systems (BESs) have attracted the attention of several stakeholders throughout the world on many counts. The bioelectricity generated from BESs has been recognized as a clean fuel. Besides, this technology has advantages such as the direct conversion of substrate to electricity, and efficient operation at ambient and even low temperatures. An overview of the BESs, its important operating parameters, bioremediation of industrial waste and wastewaters, biodegradation kinetics, and artificial neural network (ANN) modeling to describe substrate removal/elimination and energy production of the BESs are discussed. When considering the potential for use in the industrial sector, certain technical issues of BES design and the principal microorganisms/biocatalysts involved in the degradation of waste are also highlighted in this review.

Purification of domestic laundry wastewater in an integrated treatment system consists of coagulation and ultrafiltration membrane process.

An integrated unit to purify and reuse domestic laundry wastewater consisting of coagulation, sand filtration, carbon adsorption, and ultrafiltration process is developed. Chitosan and Ameztreat 102 polyamine were used as coagulants and their treatability was measured by color, turbidity and concentration of Linear Alkylbenzene Sulphonates (LAS) at various operation conditions. As a result of the trial studies, the maximum removal efficiency was attained as (i) for Chitosan- 98.2% color, 99.3% turbidity, 100% LAS removal efficiency; (ii) for Polyamine-88% color, 99% turbidity, 100% LAS. The transport mechanism of the pollutant towards the coagulant was described using kinetic models. The thickener area calculated is 0.2436 m2 for the flow rate of 100 L/h by Kynch theory. The results were recommended that the laundry wastewater be efficiently treated in the proposed treatment train and could be reused effectively.

Experiments and adaptive-network-based fuzzy inference system modelling in a hybrid up-flow anaerobic sludge blanket reactor to assess industrial azadirachtin effluent quality.

Experimental investigations were carried out for the treatment of industrial azadirachtin effluent in a hybrid up-flow anaerobic sludge blanket (HUASB) reactor continuously for 115 days in three stages at mesophilic temperature (30 - 35˚C). An adaptive-network-based fuzzy inference system (ANFIS) modelling and statistical regression analysis were applied with the raw data. In the ANFIS modelling as well as in the statistical regression analysis, the operating parameters such as initial pH, influent COD, effluent COD and biogas generation (X1, X2, X3 and X4) were taken as variables and effluent BOD values as a response (Y). The average percentage error (APE) values of ANFIS modelling were 2.18, 12.29, and 0.01%, for stage-I, II and III respectively. These values indicated that ANFIS modelling performed well in all the three stages and provided more accurate results.

Elucidation the influence of design variables on coagulation-flocculation mechanisms in the lab-scale bio-coagulation on toxic industrial effluent treatment.

Bio-coagulants are environmentally friendly substances that have shown potential in removing organic and inorganic contaminants from wastewater from the Imitation Paint Industry. Under the optimized conditions, the use of the three bio-coagulants (of plant origin), Strychnos potatorum, Cactus opuntia and Portunus sanguinolentus (crab) shell (of animal origin) were evaluated, and their removal mechanism was based on kinetic models and adsorption isotherms. The error analysis method was used to find the best isotherm fit. In addition, the kinetic model parameters showed the absence of chemisorption and confirmed the existence of pore diffusion. The interaction between coagulant and pollutant, the type, homogeneity and intensity of the coagulation process, the pollutant absorption capacity of the coagulant were evaluated with the aid of the adsorption isotherm models. From the Pseudo first-order kinetic model an equilibrium pollutant uptake (mg/g) was marked as 598, 554 and 597 for Strychnos potatorum, Cactus opuntia and Portunus sanguinolentus respectively. The better affinity between the pollutants and the bio coagulants were observed through the lower values of Langmuir isotherm constant kL. The adsorption intensity from Freundlich model (nF) were ranged between 1 and 10 for all the listed coagulants, which revealed the physisorption behavior and heterogeneous mechanism of removal. With these results, it would be possible to conduct scale-up studies to adopt the process for practical systems.

Utilization of fruit and vegetable waste to produce value-added products: Conventional utilization and emerging opportunities-A review.

Fruit and vegetables are one of the most consumed commodities globally, accounting for more than 42% of total food wastage. These vegetal foods can be consumed raw, processed, or taken as an addition to other food items. The continuous rise in population, in addition to technological advancements, has led to an imbalance in demand supply, resulting in increased food wastage globally. Although source reduction and recycling have shown promising results, more evaluations concerning economics and environmental impacts need to be given importance. The need of the hour lies in finding a possible method towards effective utilization for fruit and vegetable waste to generate value-added products which are more eco-friendly, cheaper, and sustainable. Thus, this article attempts to focus on the conventional and emerging opportunities of fruit and vegetable waste to generate value-added products. Conventional utilization, namely briquetting, waste to energy conversion, enzymatic degradation, and adsorption, as well as emerging opportunities in the areas of nutraceuticals, packaging, flavoring agents, and waste induced nanoparticles, have been emphasized. Additionally, recommendations and future perspectives towards better utilization of vegetal waste have been given importance. This review aims to narrow down the path towards evaluating the most techno-economic and efficient waste management technique for fruits and vegetable valorization, which can be promoted in the long term.

Towards zero waste production in the paint industry wastewater using an agro-based material in the treatment train.

An attempt has been made to evaluate the use of natural, agro-based material, Moringa oleifera as a coagulant in the treatment of recreated water-based paint effluent. The treatment train sequence comprising coagulation, flocculation, sedimentation, sand filtration, and membrane filtration was used. The efficiency was evaluated in terms of color and turbidity. The influence of experimental parameters such as eluent type, eluent concentration, coagulant dose, coagulant-eluate volume, initial effluent pH, and initial effluent concentration was examined. The recommended conditions to yield maximum removal efficiency are 80 mL of eluate prepared using 3 g of M. oleifera seed powder and 1 N NaCl, under actual pH, to treat a liter of effluent. The treated supernatant from coagulation unit was passed through a sand filtration setup and a membrane filtration, with a maximum removal of color above 95%. The results affirmed the positive coagulation properties of M. oleifera, which could serve as a better alternative for chemical coagulant. The optimized treatment conditions derived for the recreated paint effluent were applied in the real paint effluent treatment. An opportunity was identified for re-using treated wastewater, as a cooling fluid and a diluting agent for lower quality paints.The results affirmed the positive coagulation properties of M. oleifera, which could serve as a better alternative for chemical coagulant. Graphical abstract ᅟ.

SURGICAL OUTCOMES AND COMPLICATIONS OF RHEGMATOGENOUS RETINAL DETACHMENT IN EYES WITH CHORIORETINAL COLOBOMA: The Results of the KKESH International Collaborative Retina Study Group.

PURPOSE: To study the outcomes of management of rhegmatogenous retinal detachment in eyes with chorioretinal colobomas. METHODS: A retrospective review of 119 patients (119 eyes) with chorioretinal colobomas who underwent surgical repair for rhegmatogenous retinal detachment was performed. Data were collected on the site of the retinal break, type of surgery, anatomical success, and complications. RESULTS: The most common location of the primary retinal break was the intercalary membrane in 58.8% of eyes. The most common surgical intervention was vitrectomy with endolaser and silicone oil tamponade (77.3% of eyes). Final anatomical success was achieved in 87.4% of eyes. Anatomical success was significantly higher in eyes that received long-acting tamponade (P = 0.006). Cryotherapy was significantly associated with failure of primary vitrectomy (P = 0.028). Placement of an encircling band did not affect anatomical outcomes (P = 0.75). Most of the eyes (60%) with recurrent retinal detachment after primary vitrectomy had a primary break within the normal retina. CONCLUSION: The optimal option for managing retinal detachment in eyes with chorioretinal colobomas is pars plana vitrectomy with long-acting tamponade (silicone oil or octafluoropropane) and retinopexy to the edge of the coloboma and the primary breaks. Cryotherapy is associated with poor anatomical outcomes. An encircling band does not seem to affect the final anatomical outcome.

Pars plana vitrectomy with juxtapapillary laser photocoagulation versus vitrectomy without juxtapapillary laser photocoagulation for the treatment of optic disc pit maculopathy: the results of the KKESH International Collaborative Retina Study Group.

BACKGROUND/AIMS: To compare the functional and anatomic outcomes of pars plana vitrectomy (PPV) with juxtapapillary laser photocoagulation (JLP) versus vitrectomy without JLP in optic disc pit maculopathy. METHODS: This was a multicentre, retrospective study of 46 consecutive patients with optic disc pit maculopathy presenting at tertiary eye centres between 1992 and 2012. Indications for surgery included distorted or decreased vision. Surgical intervention included PPV, posterior vitreous detachment, with or without gas tamponade. Twenty-four patients received laser photocoagulation at the temporal edge of the optic disc pit (group A) and 22 patients had no laser (group B). Postoperative best-corrected visual acuity (BCVA) and optical coherence tomography findings were the main outcome measures. RESULTS: Mean follow-up was 44 months (range 12-98 months). BCVA in group A improved significantly from 0.7 logMAR (20/100) preoperatively to 0.5 logMAR (20/60) postoperatively (p=0.017). In group B, BCVA improved from 0.7 logMAR (20/100) preoperatively to 0.4 logMAR (20/40) postoperatively (p=0.014). The difference in final BCVA between groups was not statistically significant (p=0.693). The mean central macular thickness (CMT) in group A improved significantly from 750 µm preoperatively to 309 µm at last follow-up (p<0.0001). The mean CMT in group B improved from 616 µm preoperatively to 291 µm at last follow-up (p=0.028). The difference in final CMT between groups was not statistically significant (p=0.747). CONCLUSIONS: PPV with JLP for optic disc pit maculopathy had similar functional and anatomic outcomes compared with vitrectomy without JLP.