Paradigm shift in Nutrient-Energy-Water centered sustainable wastewater treatment system through synergy of bioelectrochemical system and anaerobic digestion.

With advancements in research and the necessity of improving the performance of bioelectrochemical system (BES), coupling anaerobic digestion (AD) with BES is crucial for energy gain from wastewater and bioremediation. Hybridization of BES-AD concept opens new avenues for pollutant degradation, carbon capture and nutrient-resource recovery from wastewater. The strength of merging BES-AD lies in synergy, and this approach was employed to differentiate fads from strategies with the potential for full-scale implementation and making it an energy-positive system. The integration of BES and AD system increases the overall performance and complexity of combined system and the cost of operation. From a technical standpoint, the primary determinants of BES-AD feasibility for field applications are the scalability and economic viability. High potential market for such integrated system attract industrial partners for more industrial trials and investment before commercialization. However, BES-AD with high energy efficacy and negative economics demands performance boost.

Assessing the performance of polyphosphate accumulating organisms in a full-scale side-stream enhanced biological phosphorous removal.

Phosphorous (P) removal in wastewater treatment is essential to prevent eutrophication in water bodies. Side-stream enhanced biological phosphorous removal (S2EBPR) is utilized to improve biological P removal by recirculating internal streams within a side-stream reactor to generate biodegradable carbon (C) for polyphosphate accumulating organisms (PAOs). In this study, a full-scale S2EBPR system in a water resource recovery facility (WRRF) was evaluated for 5 months. Batch experiments revealed a strong positive correlation (r = 0.91) between temperature and C consumption rate (3.56-8.18 mg-COD/g-VSS/h) in the system, with temperature ranging from 14°C to 18°C. The anaerobic P-release to COD-uptake ratio decreased from 0.93 to 0.25 mg-P/mg-COD as the temperature increased, suggesting competition between PAOs and other C-consumers, such as heterotrophic microorganisms, to uptake bioavailable C. Microbial community analysis did not show a strong relationship between abundance and activity of PAO in the tested WRRF. An assessment of the economic feasibility was performed to compare the costs and benefits of a full scale WRRF with and without implementation of the S2EBPR technology. The results showed the higher capital costs required for S2EBPR were estimated to be compensated after 5 and 11 years of operation, respectively, compared to chemical precipitation and conventional EBPR. The results from this study can assist in the decision-making process for upgrading a conventional EBPR or chemical P removal process to S2EBPR. PRACTITIONER POINTS: Implementation of S2EBPR presents adaptable configurations, exhibiting advantages over conventional setups in addressing prevalent challenges associated with phosphorous removal. A full-scale S2EBPR WRRF was monitored over 5 months, and activity tests were used to measure the kinetic parameters. The seasonal changes impact the kinetic parameters of PAOs in the S2EBPR process, with elevated temperatures raising the carbon demand. PAOs abundance showed no strong correlation with their activity in the full-scale S2EBPR process in the tested WRRF. Feasibility assessment shows that the benefits from S2EBPR operation can offset upgrading costs from conventional BPR or chemical precipitation.

Effects of Rumex nervosus leaf powder supplementation on carcasses compositions, small intestine dimensions, breasts color quality, economic feasibility in broiler chickens.

Carcass characteristics, product quality, and the conversion of feed into meat with higher performance and feasibility are important determinants of the profitability and sustainability of any poultry enterprise. The objective of this study was to investigate the potential effect of Rumex nervosus leaf powder (RNLP) on carcass composition, small intestine dimensions, breast color quality, and economic feasibility of Ross broiler chickens. A total of 122 broilers were randomly distributed evenly among 4 treatments (0, 1, 3, and 5 g RNLP/ kg diet, n = 5 replicates per treatment, with 6 broilers per replicate: 3 ♀ and 3 ♂). Performance and economic data were collected in each replicate during the experiment. One male bird from each replication was examined for other criteria on d 34. Results showed that broilers fed 3 g of RNLP had a higher eviscerated carcass weight and dressing percentage (P < 0.05) than the control. The RNLP-fed broilers had higher weights and thicknesses in the duodenum and jejunum of up to 5 g and in the ileum and overall small intestine of up to 3 g. Broilers fed the lowest levels of RNLP had the highest revenue and net gain and the lowest cost-benefit ratio compared with those fed the highest levels of RNLP. The results indicate that the addition of RNLP has a positive effect on carcass processing, the intestinal measurements, and profitability ratios of the broilers. The 1 g RNLP/kg feed is the recommended dose to increase productivity and economic profitability ratios per kilogram of meat.

Magnetic-watermelon rinds biochar for uranium-contaminated water treatment using an electromagnetic semi-batch column with removal mechanistic investigations.

Biosorption using modified biochar has been increasingly adopted for the sustainable removal of uranium-contaminated from an aqueous solution. In this research study, the facile preparation and surface characteristics of magnetized biochar derived from waste watermelon rind to treat U(VI) contaminated water were investigated. The porosity, specific surface area, adsorption capacity, reusability, and stability were effectively improved after the magnetization of biochar. The kinetics and isotherm studies found that the U(VI) adsorption was rate-limiting monolayer sorption on the homogeneous surface of magnetized watermelon rind biochar (MWBC). The maximum adsorption capacity was found to be 323.56 mg of U(VI) per g of MWBC at pH 4.0 and 293 K that was higher than that of watermelon rind biochar (WBC) (135.86 mg g-1) and other sourced biochars. The surface interaction mechanism, environmental feasibility, applicability for real-filed water treatment studied in the electromagnetic semi-batch column, and reusability of MWBC were also explored. Furthermore, salient raised the ion exchange and complexation action capacity of MWBC due to the presence of Fe oxide. The overall results indicated that MWBC was not only inexpensive and had a high removal capacity for U(VI), but it also easily enabled phase separation from an aqueous solution, with more than three times reusability at a minimum removal capacity of 99%.

Maize (Zea mays L.) yield response to the effect of blended fertilizer and varieties under supplemental irrigation at Hadero Zuria Kebele, southern Ethiopia.

Maize is one of the staple cereal crops in Ethiopia. However, in southern Ethiopia, the productivity of the crop is very low as compared to the average national productivity, which is mainly attributed to poor soil fertility and the use of low yielding varieties. Hence, a field experiment was conducted at Hadero Zuria kebele, southern Ethiopia under supplemental irrigation to investigate the effects of different rates of blended Nitrogen, Phosphorus, Sulphur, and Boron (NPSB) fertilizer on the performance of maize varieties. Treatments involving three varieties of maize (30G19, BH-546, and BH-547) and six rates of NPSB fertilizer (0, 50, 75, 100, 125, and 150) kg ha-1 were tested in RCBD using a factorial arrangement with three replications. Data on crop Phenological, growth, yield, and yield components were collected. The results showed that the blended NPSB fertilizer rates and varieties of maize affected days to physiological maturity, leaf area, leaf area index, hundred kernels weight (HKW), dry biomass yield (DBY), and grain yield (GY). The highest mean values for HKW, DBY, and GY were obtained from the 150 kg ha-1 NPSB rate. Similarly, the highest values for DBY and GY were obtained from the BH-546 variety. Significant differences (P < 0.05) were obtained on days to tasseling, days to silking, and harvest index (HI) due to the interaction effect of NPSB rates and varieties. As the NPSB rates increased from 0 to 150 kg ha-1, HKW and DBY increased consistently from 29.62 to 36.62 g and 31.41 to 43.70 t ha-,1 respectively. Grain yield showed a highly significant and positive correlation with cob length, leaf number, HI, HKW, and DBY. Also, maximized economic profitability was gained at a rate of 150 kg ha-1 NPSB fertilizer. Thus, from this result, the NPSB rate of 150 kg ha-1 with the hybrid maize variety BH-546 could be better for the study area.

Nutrients recovery from treated secondary mainstream in an urban wastewater treatment plant: A financial assessment case study.

This study presents the financial assessment for implementing an ammonium and phosphate simultaneous recovery process based on the use of calcium activated synthetic zeolites in a large urban Waste Water Treatment Plant (WWTP) located in the Metropolitan Area of Barcelona. A calcium activated synthetic zeolites was selected, after a benchmarking analysis, as it reported capability for simultaneously recover ammonium and phosphate by a combined mechanism of ion exchange for ammonium and formation of insoluble mineral phase for phosphate. The loaded sorbent, rich in ammonium and phosphate, can be used as slow-release fertilizer. Financial indexes such as the net present value, the internal return rate, the return of investment and the payback period were calculated concluding that the integration of a zeolite-based sorption treatment stage in the main stream is economically feasible, with a reasonable payback period. The need, to achieve low-levels of P and N on the discharged waters and the need to develop more sustainable WWTP facilities indicate that the deployment of nutrient recovery solutions will be encouraged. The sensitivity analysis carried out to define the critical parameters of the economic performance of the technology allows concluding that the main variable in the viability of the nutrient recovery unit is related to the nutrients sorbent, both in the cost of purchase and in the market for the sorbent loaded with nutrients.

Performance of beef heifers supplemented with sodium lasalocid.

This study was conducted on 78 13-month-old crossbred beef heifers that weighed 215 kg in Southern Rio Grande do Sul (RS) State, Brazil. We evaluated the performance of beef heifers that were reared in a pasture system that received a mineral supplement energy-type protein with added sodium lasalocid (LAS). The heifers were randomly and uniformly divided into 2 groups, with 39 animals in each group. One group of animals received a mineral supplement energy-type protein without sodium lasalocid (CON), and the other group received a mineral supplement energy-type protein with added LAS. The mean feed intake, the body weight (BW), the average daily gain (ADG), the body condition score (BCS), and ovarian cyclicity were recorded, and economic parameters were calculated. No differences in supplement intake were observed between the groups, which ensures adequate intake of the other components of the mineral mixture, which are part of the nutritional requirements for the production process. Similarly, no difference in the ADG was observed between treatments. We observed that the heifers in the LAS group had a higher BW gain (51 kg) that the CON heifers (40 kg; P < 0.05). In addition, LAS-supplemented heifers had a higher BCS (3.53) than CON heifers (3.38) at the end of the experiment (P < 0.05). The heifers supplemented with LAS had a higher profitability than the CON heifers, even with the higher cost of the supplement containing LAS; this effect was due to the higher live BW at the end of the study. We concluded that the administration of a mineral supplement energy-type protein with added LAS has beneficial effects on beef heifers in terms of production and economic feasibility.

Profits from pollutants: Economic feasibility of integrated anaerobic digester and nutrient management systems.

There has been sustained interest from both environmental regulators and livestock associations to expand the use of anaerobic digester (AD) technology to mitigate greenhouse gas emissions. However, the generally profitable practice of codigesting off-farm organic waste could increase nitrogen and phosphorus content to the farm and exacerbate nutrient over-application concerns near large animal operations. We examine the economic feasibility of a broad set of dairy waste management systems composed of two technology groups that mitigate air and water pollution: an AD system that includes either animal waste input or combination animal/off-farm organic waste codigestion input and either compressed natural gas (CNG) or combined heat and power (CHP) output; and a filtration system that includes fiber separation, nutrient separation, and/or water recovery. We conclude that AD setups without codigestion are only economically feasible under limited conditions, but scenarios which use codigestion have the potential to contribute to nutrient over-application without nutrient separation technology. Trends for CNG and CHP match closely. Net present value (NPV) is greatest for AD with CNG scenarios. Estimated NPV for AD with CNG and environmental credits is $1.8 million and $39.7 million for dairies with 1600 and 15,000 wet cow equivalents, respectively. For these firm sizes, the addition of codigestion contributes $4.8 million and $47.3 million, respectively, to estimated NPV. Nutrient separation and water recovery both lead to decreases in scenario NPV with codigestion, but with the right policies, dairy owners may be willing to adopt AD with nutrient separation.