Innovative Wastewater Treatment Technologies for Resource-Saving Activities of Feed Mills

Introduction. National economies are looking for tools to activate the explicit and hidden resource potential. Innovative resource-saving projects are such a tool. Feed production strives to increase its resource efficiency. Study objects and methods. The present research featured the feed industry of the Russian Federation and regional feed mills. It involved structural, functional, and systematic approaches and standard research methods. Results and discussion. Liquid waste proved to be an important resource potential of modern feed production. It contains substances with high nutritional, biological, and energy value and can be used to produce methionine. The experimental part featured an industrial enterprise in the Voronezh region, which expects to produce 1452 tons of methionine worth 58 080 thousand rubles. The profitability will be 616.76%, the gross return on sales − 86.1%, the payback time – 1.44 months, the efficiency of capital investments – 8.45. Conclusion. The innovative project will reduce the negative impact on the environment, increase the resource efficiency of the enterprise, and provide additional income.

Evaluation of the economic viability of grid-connected photovoltaic systems in different Brazilian regions

This study aimed at the dimensioning and economic analysis of grid-connected photovoltaic systems in different cities in Brazil. As a criterion for the selection of the cities of interest, it was considered the capital with the highest number of residences in each of the five regions of the country, as well as the city where the authors are established, namely the cities of Salvador, Manaus, Goiânia, São Paulo, Curitiba, and Cascavel. Based on local characteristics and adopting an average monthly electricity consumption of 400 kWh, was developed the dimensioning of the photovoltaic systems, adopting the methodology presented by Pinho and Galdino (2014). Based on the components determined for the systems, budgets were made to enable their implementation. The investments to be made varied between US$ 4,682.97 and US$ 5,326.06. From these values, economic analyses were made using the discounted payback method. The projects presented different payback times, with the shortest payback time to the city of Manaus, with 9 years and the longest in the city of Curitiba, with 15 years. Therefore, it was confirmed the research hypothesis that the regional characteristics linked to the dimensioning of the photovoltaic systems directly affect the time of return on investment.

Multi-criteria prioritization of the renewable power plants in Australia using the fuzzy logic in decision-making method (FMCDM)

The presented study focused on developing an innovative decision-making framework to select the best renewable-power-plant technologies, considering comprehensive techno-economic and environmental variables. Due to the favourable conditions, Australia was selected as the case study. A fuzzy-logic method and analytical hierarchy process were applied to prioritize different renewable-energy power plants. The techno-economic factors included levelized cost of energy, initial cost, simple payback time, and operation and maintenance costs along with environmental factors including carbon payback time, energy payback time and greenhouse-gas emissions were used to rank the power plants. The results showed that the capital cost and simple payback time had the highest priority from an economic point of view. In comparison, greenhouse-gas emissions and carbon payback time were the dominant environmental factors. The analysis results provided economic and environmental priority tables for developing different power plants in the current state and a future scenario by 2030. The fuzzy results and pairwise composite matrix of alternatives indicated that the onshore wind, offshore wind, single-axis tracker polycrystalline photovoltaic, single-axis tracker monocrystalline photovoltaic, fix-tilted polycrystalline photovoltaic and fix-tilted monocrystalline photovoltaic scored the highest in the current state. In contrast, by 2030, the single-axis tracker photovoltaic power plants will be the best choice in the future scenario in Australia. Finally, the results were used and analysed to recommend and suggest several policy implementations and future research studies.

Influence of Different Allocation Methods for Recycling and Dynamic Inventory on CO2 Savings and Payback Times of Light-Weighted Vehicles Computed under Product- and Fleet-Based Analyses: A Case of Internal Combustion Engine Vehicles

Light weighting by material substitution is a key to reducing GHG emissions during vehicle operation. The GHG benefits are a salient factor in selecting lightweight materials for vehicles. Although the literature has performed lightweight material selections using GHG benefits under product- and fleet-based life-cycle inventory (LCI) analyses, recycling effects have therein been accounted for by arbitrarily selecting allocation methods for recycling, as the consensus on their selection is absent. Furthermore, studies have mistreated the temporal variations of the LCI parameters (the dynamic inventory (DI)), though that could be an important factor affecting the overall LCI results when allocation methods for recycling are in place. Therefore, to investigate their influence on greenhouse gas (GHG) benefit evaluations, an LCI case study was conducted, centered on aluminum- and magnesium-substituted internal combustion engine vehicles (ICEVs) at the product- and fleet- levels. “CO2 savings” and the “CO2 payback time”, as well as four allocation methods for recycling, were considered to represent the GHG benefits and address the recycling effects, respectively. The dynamic inventory was based on the world average electricity grid mix change. The results indicate that changing the conditions of the DI and the allocation methods for recycling could alter the better performing material under fleet-based analyses. Therefore, we ascertained that the choice of the allocation method for recycling and conducting fleet-scale dynamic LCI analyses in the presence of the DI is pivotal for material selections.

Comparison between double slope solar still and fourfold slope solar still: energy, exergy, exergoeconomic, and enviroeconomic evaluation

This paper proposes a single basin fourfold slope solar still, which includes a fourfold slope glass cover plate used for solar heat collection and steam condensation. In order to show the efficiency of fourfold slope solar still, comparative experiments are conducted under the winter climate conditions in Hangzhou for testing the operational performance of double slope type solar still (DOSS) and fourfold slope still (FOSS), so as to make a comparative analysis between them. Results show that the productivity of fourfold slope still is 19.51% higher than that of double slope still, and fourfold slope solar still enhances the average hourly energy efficiency by 31.11%. According to the energy method, the energy payback time values of fourfold slope solar still and double slope solar still are 64.88 months and 75.42 months respectively. According to the environmental parameter method, FOSS and DOSS reduce 5.47 tons and 4.58 tons of CO2 respectively. The corresponding values based on the exergy environment parameters are 0.21 and 0.18 tons of CO2, respectively. The fourfold slope solar still has more obvious emission reduction function than the double slope solar still. The cost of distilled water of fourfold slope solar still is 0.28 RMB/kg, and the cost of double slope solar still is 0.30 RMB/kg. In addition, the environmental and economic parameters of fourfold slope still and double slope still are 79.29$ (561.37RMB) and 66.35$ (469.76RMB), respectively. While, the corresponding values based on the exergoenvironmental parameter are 3.05$ (21.59RMB) and 2.56$ (18.12RMB), respectively. From the analysis of exergoeconomic and exergoenvironmental parameters, fourfold slope single basin solar still appears to be more effective.

Effects of elevated CO2 concentration and nitrogen addition on the chemical compositions, construction cost, and payback time of subtropical trees in Cd-contaminated mesocosm soil

Rising atmospheric CO2 concentration ([CO2]) and nitrogen (N) deposition are changing plant growth, physiological characteristics, and chemical compositions; however, few studies have explored such impacts in a heavy-metal-contaminated environment. In this study, we conducted an open-top chamber experiment to explore the impacts of two years of elevated atmospheric [CO2] and N addition on the growth, physiological characteristics, and chemical compositions of five subtropical tree species in a cadmium (Cd)-contaminated environment. Results showed that N addition significantly increased concentration of leaf N and protein in five tree species, and also decreased payback time (PBT) and leaf C:N ratios and increased tree relative height growth rate (RGR-H) and basal diameter growth rate (RGR-B) in Liquidambar formosana and Syzygium hainanense. Elevated [CO2] increased leaf maximum photosynthetic rate (Amax) and concentration of total non-structural carbohydrates (TNC) and shortened PBT to offset the negative effect of Cd contamination on RGR-B in A. auriculiformis. The combined effects of elevated [CO2] and N addition did not exceed their separate effects on RGR-H and RGR-B in Castanopsis hystrix and Cinnamomum camphora. N addition significantly increased the concentration of leaf Cd by 162.1% and 338.0%, and plant Cd bio-concentration factor (BCF) by 464% and 861% in C. hystrix, and C. camphora, respectively, compared to Cd addition. Among the five tree species, the decreases in PBT and the increases in Amax, RGR-B, and concentrations of leaf protein in response to N and Cd addition under elevated [CO2] were average higher 86.7% in A. auriculiformis than other species, suggesting that the mitigation of the negative effects of Cd pollution by elevated [CO2] and N addition among five species was species-specific. Overall, we concluded that N addition and elevated [CO2] reduced Cd toxicity, and increased the growth rate in A. auriculiformis, S. hainanense and L. formosana, while maintained the growth rate in C. hystrix, and C. camphora by differently increasing photosynthetic rate, altering the leaf chemical compositions, and shortening PBT.

Bipolar Membrane Electrodialysis for Sulfate Recycling in the Metallurgical Industries

Demand for nickel and cobalt sulfate is expected to increase due to the rapidly growing Li-battery industry needed for the electrification of automobiles. This has led to an increase in the production of sodium sulfate as a waste effluent that needs to be processed to meet discharge guidelines. Using bipolar membrane electrodialysis (BPED), acids and bases can be effectively produced from corresponding salts found in these waste effluents. However, the efficiency and environmental sustainability of the overall BPED process depends upon several factors, including the properties of the ion exchange membranes employed, effluent type, and temperature which affects the viscosity and conductivity of feed effluent, and the overpotentials. This work focuses on the recycling of Na2SO4 rich waste effluent, through a feed and bleed BPED process. A high ion-exchange capacity and ionic conductivity with excellent stability up to 41 °C is observed during the proposed BPED process, with this temperature increase also leading to improved current efficiency. Five and ten repeating units were tested to determine the effect on BPED stack performance, as well as the effect of temperature and current density on the stack voltage and current efficiency. Furthermore, the concentration and maximum purity (>96.5%) of the products were determined. Using the experimental data, both the capital expense (CAPEX) and operating expense (OPEX) for a theoretical plant capacity of 100 m3 h−1 of Na2SO4 at 110 g L−1 was calculated, yielding CAPEX values of 20 M EUR, and OPEX at 14.2 M EUR/year with a payback time of 11 years, however, the payback time is sensitive to chemical and electricity prices.

Pharmacy-based screening to detect persons at elevated risk of type 2 diabetes: a cost-utility analysis

Background Early identification of people at elevated risk of type 2 diabetes (T2D) is an important step in preventing or delaying its onset. Pharmacies can serve as a significant channel to reach these people. This study aimed to assess the potential health economic impact of screening and recruitment services in pharmacies in referring people to preventive interventions. Methods A decision analytic model was constructed to perform a cost-utility analysis of the expected national health economic consequences (in terms of costs and quality-adjusted life years, QALYs) of a hypothetical pharmacy-based service where people screened and recruited through pharmacies would participate in a digital lifestyle program. Cost-effectiveness was considered in terms of net monetary benefit (NMB). In addition, social return on investment (SROI) was calculated as the ratio of the intervention and recruitment costs and the net present value of expected savings. Payback time was the time taken to reach the break-even point in savings. In the base scenario, a 20-year time horizon was applied. Probabilistic and deterministic sensitivity analyses were applied to study robustness of the results. Results In the base scenario, the expected savings from the pharmacy-based screening and recruitment among the reached target cohort were 255.3 m€ (95% CI − 185.2 m€ to 717.2 m€) in pharmacy visiting population meaning 1412€ (95% CI − 1024€ to 3967€) expected savings per person. Additionally, 7032 QALYs (95% CI − 1344 to 16,143) were gained on the population level. The intervention had an NMB of 3358€ (95% CI − 1397€ to 8431€) using a cost-effectiveness threshold of 50,000 €/QALY. The initial costs were 122.2 m€ with an SROI of 2.09€ (95% CI − 1.52€ to 5.88€). The expected payback time was 10 and 8 years for women and men, respectively. Results were most sensitive for changes in effectiveness of the intervention and selected discount rate. Conclusions T2D screening and recruitment to prevention programs conducted via pharmacies was a dominant option providing both cost savings and QALY gains. The highest savings can be potentially reached by targeting recruitment at men at elevated risk of T2D.

Risk Analysis on PMMA Recycling Economics

Poly(methyl methacrylate) (PMMA) is a versatile polymer with a forecast market of 4 Mtons/y by 2025, and 6 USD billion by 2027. Each year, 10% of the produced cast sheets, extrusion sheets, or granules PMMA end up as post-production waste, accounting for approximately 30 000 tons/y in Europe only. To guide the future recycling efforts, we investigated the risks of depolymerization process economics for different PMMA scraps feedstock, capital expenditure (CAPEX), and regenerated MMA (r-MMA) prices via a Monte-Carlo simulation. An analysis of plastic recycling plants operating with similar technologies confirmed how a maximum 10 M USD plant (median cost) is what a company should aim for, based on our hypothesis. The capital investment and the r-MMA quality have the main impacts on the profitability. Depending on the pursued outcome, we identified three most suitable scenarios. Lower capital-intensive plants (Scenarios 4 and 8) provide the fastest payback time, but this generates a lower quality monomer, and therefore lower appeal on the long term. On 10 or 20 years of operation, companies should target the very best r-MMA quality, to achieve the highest net present value (Scenario 6). Product quality comes from the feedstock choice, depolymerization, and purification technologies. Counterintuitively, a plant processing low quality scraps available for free (Scenario 7), and therefore producing low purity r-MMA, has the highest probability of negative net present value after 10 years of operation, making it a high-risk scenario. Western countries (especially Europe), call for more and more pure r-MMA, hopefully comparable to the virgin material. With legislations on recycled products becoming more stringent, low quality product might not find a market in the future. To convince shareholders and government bodies, companies should demonstrate how funds and subsidies directly translate into higher quality products (more attractive to costumers), more economically viable, and with a wider market.