Chemical Costs Research Articles

Investigation of impact of split treatment on finished water quality for the Ames water treatment plant.

In response to limited carbon dioxide availability and increasing costs during the COVID-19 pandemic, an investigation into split treatment was performed. A 2020 pilot study showed that a 5% raw water bypass and target caustic alkalinity range of 26-36 mg/L as CaCO3 resulted in 25% and 7% carbon dioxide and lime savings, respectively. Considering this promising outcome, the potential for scaling and corrosion within the plant was evaluated during a subsequent split treatment trial in this study. Mild steel scale coupons were assessed for scaling and corrosion at four different treatment conditions. These results found that a 5% raw water bypass is predicted to have a minimal impact of scaling and corrosion on the water plant infrastructure when compared to full lime softening. Results are significant since split treatment can save over $150,000 annually with no apparent change in water quality, improving the plant's resilience and sustainability. PRACTITIONER POINTS: A 5% raw water bypass produced scale and corrosion similar to full lime softening. Localized build-up results in surface corrosion. Relocation of SHMP did not show appreciable sequestration of hardness ions. Adjusting dosage and/or using a polyphosphate blend is recommended. A 5% raw water bypass can be implemented at a lime softening facility to reduce chemical usage and cost. A similar procedure can be conducted to analyze the impacts of a larger percent bypass for additional chemical savings.

A Study on Constraint Analysis of Rice Cultivation in Korba District of Chhattisgarh, India

Rice is a vital staple food in Chhattisgarh, making it essential to address the challenges faced by rice farmers in the Korba District. This study focuses on issues related to rice cultivation and marketing in the region. The research was conducted in the Korba district, which comprises five blocks: Pali, Korba, Katghora, Kartala, and Podi-Uproda. Among these, the Katghora block was selected purposefully due to its significant paddy cultivation and associated challenges. Within this block, Vijaypur village was chosen as the study area. A total of 50 respondents, representing 22% of the farmers in the area, were selected for the study.Data were collected and analyzed using content analysis, incorporating qualitative methods such as in-depth interviews, group discussions, and observation techniques. The findings revealed that the primary challenges in rice cultivation included a lack of knowledge about the recommended package of practices (Rank I), high costs of fertilizers and plant protection chemicals (Rank II), and insufficient irrigation water (Rank III).On the marketing side, the major constraints identified were inadequate transportation facilities (Rank I), farmers being compelled to sell their produce locally due to low production volumes (Rank II), and issues arising from small quantities of produce (Rank III). Additional challenges discussed include crop diseases, insect pests, limited knowledge of improved, high-yielding, and disease-resistant varieties, and insufficient institutional support during both production and marketing.

Reactive carbon capture using saline water: evaluation of prospective sources, processes, and products.

Reactive carbon capture (RCC) processes involve the capture of carbon dioxide (CO2) and conversion to a value-added product using a single sorbent/reaction medium. Not only can RCC processes generate valuable byproducts that can reduce the cost of carbon capture, but RCC tends to have lower energy demand than processes involving the transfer of CO2 between the mediums used for capture and subsequent reactions. Saline water has been proposed as a potential medium for RCC due to it's relative abundance and low cost. Additionally, the composition and chemistry of many saline water sources: (1) elevates the CO2 content (as compared to atmospheric concentrations), (2) provides various cations that can form valuable products with CO2, and (3) enhances the kinetics of chemical reactions used to convert CO2 to stable byproducts. In addition to established industrial processes for converting CO2 into inert or valuable byproducts, we found 20 new processes and technologies that have been developed specifically to capture and convert CO2 using saline water. Both preexisting and emerging processes can be broadly classified as electrochemical or chemical titration processes. When assessing the potential viability of applying any of these processes for large scale carbon capture, several factors must be considered, such as the net carbon footprint of the process, the market size, location of customers and value of the end product, the energy demand and chemical costs of the process, and any other environmental impacts. The feasability of many emerging saline-based RCC processes is difficult to determine, as many technologies were tested using synthetic saline waters and/or concentrated CO2 sources. Notwithstanding the early stage of development of many saline-based RCC technologies, the major limitation to implementation of this approach to carbon capture is the mismatch in the scale of the markets for products of saline-based RCC and the scale of carbon capture needed to meet climate goals. However, because the products of many of the processes reviewed here are stable and non-hazardous, these technologies may also be used for carbon sequestration efforts where the products are managed as waste, in which case the carbon capture potential of these technologies can surpass the market-imposed limitations on RCC. Thus, the potential benefits of saline water-based RCC identified in this review encourage further study and development of these technologies.

Alkaline coagulation for separation of outdoor anaerobically cultured microalgae using natural-based coagulant

Although, native microalgae (MA) grows in alkaline environments, there is a lack of information from previous studies on the separation of microalgae culture under alkaline coagulation-flocculation-sedimentation (CFS) conditions. This study evaluated the separation efficiency of tannin (TA), Moringa oleifera seed extract (MOSE) natural coagulants in comparison with Aluminum sulfate (AS) for harvesting MA grown in anaerobically digested sanitary wastewater in a pilot flat panel photobioreactor in outdoor environment. The aim was to establish a pathway for recovery of microalgae biomass and supernatant without pH control and save cost for pH adjustment chemicals, in alignment with the circular economy concepts. Total suspended solids (TSS), turbidity and MA concentration (optical density – OD) were monitored throughout the tests. Optimum dosages of TA (1100 mg l−1), MOSE (3000 mg l−1) and AS (320 mg l−1) determined from jar tests were evaluated after MA cultivation, with natural pH of 10.4 under CFS condition (Coagulation: velocity gradient (Gf) of 200 s−1 for 2 min, flocculation: Gf of 10 s−1 for 15 min and sedimentation: 10 min observation time). TA and AS presented similar high removal efficiencies for turbidity (≥ 95 %), OD (≥ 87 %) and TSS (≥ 62 %). However, TA recorded a good pH (7.6) for the supernatant compared to an unsatisfactorily low 5.2 for AS. TA presented the potential of harvesting MA biomass without prior pH control and without adversely impacting the medium's pH. This shows that biomass has a potential usage as a biofertiliser and as well the resultant supernatant is reusable for non-potable purposes.

Using process modeling and simulation to determine the sustainability of a novel lactic acid biorefinery in Europe: Influence of process improvements, scale, energy source, and market conditions

The biorefinery concept aims to produce multiple high-value products from bio-based feedstocks. One such product is lactic acid, which is used across several industries such as food, pharmaceuticals, cosmetics, and chemicals. Lactic acid yield is influenced by several factors, and improvements in performance are often first demonstrated at lab-scale, requiring prospective models which make assumptions about how the system will be optimized to understand the potential of a commercial-scale plant. This study assesses the economic and environmental sustainability of a proposed lactic acid biorefinery through the combination of process modelling, techno-economic assessment, and life cycle assessment. The case study proposes producing high purity lactic acid from industrial candy waste and liquid digestate in Denmark through lactic acid fermentation and downstream membrane separations. A base case is first modelled to determine the economic and environmental hotspots of the system; scenarios are then modelled where improvement methods are implemented reducing consumption of energy, chemicals, water, and the production of waste, upscaling the system, and integrating bioenergy. Finally, a cost sensitivity analysis is run varying bioenergy, water, chemical, and labor costs based on the European market. By optimizing unit processes, scale, energy sources and market conditions, the lactic acid unit production cost and global warming potential can be lowered by 94% and 80% compared to the base case, respectively. However, these are optimized in different scenarios, indicating a trade-off in optimizing economic and environmental criteria. As even best-case lactic acid unit production cost is found to be 141–232% higher than market price, this production pathway will require further improvement or market changes before it can be commercially viable.

Investigating Crude Glycerol Electrooxidation

Decarbonization of chemical manufacturing requires a range of strategies, including the utilization of process waste. This waste can then be used in processes powered by renewable electricity, such as electrocatalysis, to synthesize other useful chemicals. In doing so, process waste is reduced and industrially-relevant chemicals are produced without the use of fossil fuel-based feeds.One intriguing candidate feedstock for electrocatalytic conversion to relevant chemicals is glycerol, produced as a byproduct of biodiesel production at ~10% by mass. Glycerol electrooxidation can produce up to 12 different compounds, all with relevant industrial uses. Prior work has studied glycerol electrooxidation extensively to understand the mechanisms by which these compounds are produced on a variety of different catalysts.1,2 However, most of these studies utilize 99+% pure glycerol to investigate these mechanisms. There is very limited information on the electrooxidation of impure, or “crude,” glycerol – the glycerol that will exit the biodiesel production process in an industrial setting. This crude glycerol is made up of a mixture of glycerol, methanol, sodium hydroxide, and water, and its composition varies dramatically depending on the manufacturer. It is critical to understand the electrooxidation of crude glycerol to effectively scale the reaction.In this work, we investigate the electrooxidation of crude glycerol in scalable flow electrolyzers on precious3 and nonprecious metal catalysts. Using a multifaceted approach that includes system design, reaction engineering, and technoeconomic analysis, we explore the electrochemical performance of relevant compositions of crude glycerol and identify approaches to improve and augment that performance in terms of chemical production and cost efficiency.(1) Fleischmann, M.; Korinek, K.; Pletcher, D. The Oxidation of Organic Compounds at a Nickel Anode in Alkaline Solution. Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 1971.(2) Houache, M. S. E.; Hughes, K.; Baranova, E. A. Study on Catalyst Selection for Electrochemical Valorization of Glycerol. Sustainable Energy and Fuels, 2019.(3) Gaines, R. N.; Kleimenhagen, B. A.; Griebler, J. J.; Harris, L. C.; Gewirth, A. A.; Rogers, S. A.; Kenis, P. J. A. Optimizing the Flow Electrooxidation of Glycerol Using Statistical Design of Experiments. Journal of the Electrochemical Society, 2024.

A multi-dimensional comparative study on the performance of algae removal using various flotation

Flotation is considered the most cost-effective and efficient algae-water separation technology. However, there are various flotation techniques for algae removal, such as coagulation-flotation (CF), foam flotation (FF), and positively charged bubble flotation (PF). It remains unclear which method is most suitable for removing algae from water bodies and under what specific conditions each technique is most effective. This study systematically compares CF, FF, and PF in terms of algal cell removal efficiency, concentration ratio, flotation kinetics, impact on algal cells, removal efficiency of algal organic matter (AOM), microcystins (MC-LR) and disinfection by-products (DBPs), as well as economic cost analysis. CF is better suited for algae removal in water bodies, including drinking water sources, using fixed installations on shore due to its high removal efficiency, high concentration ratio, low chemical dosage, minimal residuals, and low risk of generating DBPs. FF is more appropriate for non-drinking water sources as it can remove algae and further control algal growth; however, its residual CTAB may pose a threat to drinking water safety. PF is most suitable for in situ algae removal within water bodies, primarily because it does not require stirring or coagulation. Instead, modified bubbles can be directly introduced into the algal distribution layer, where they adhere to algal cells, facilitating algae-water separation. All three flotation methods are economically feasible for algae removal. For FF, the costs of chemicals and electricity are nearly equal, while for CF and PF, the primary cost is electricity. This study provides data to support the selection of appropriate flotation technologies for emergency removal of algal blooms in water bodies.

Global techno-economic analysis of MBR for hospital wastewater treatment

This study comprehensively examines and characterizes global membrane bioreactor (MBR) practices for hospital wastewater treatment, focusing on development trends, technical performance (pollutant removal and carbon emissions), and economic costs, including both capital expenditures (CAPEX) for civil engineering and equipment procurement, and operational expenditures (OPEX) for electricity, membrane replacement, labor, and chemical costs, as well as system footprint. The results show that MBR has been widely used for hospital wastewater treatment for over two decades, with global applications and scales significantly increasing, especially after the COVID-19 pandemic. A notable shift in membrane types has occurred, with hollow fiber membranes dominating before 2010 and flat inorganic membranes gaining prominence after 2020. MBR not only effectively removes conventional pollutants but also greatly reduces pathogens, ARBs and ARGs before disinfection, thus alleviating the subsequent disinfection burden. In addition, MBR is a crucial step in the process of completely removing emerging contaminants (ECs) that pose significant environmental and health risks. The CAPEX of MBR has decreased at the technical level in recent years. MBR requires only 62 % and 21 % of footprint for conventional activated sludge (CAS) and biofilm-based processes, respectively. MBR's land-saving advantage offsets the CAPEX gap with CAS in high land-cost areas. From before 2010 to after 2020, membrane costs saw the largest reduction in OPEX, dropping by 71 %, while electricity consumption saw a 10.71 % reduction, now comparable to biofilm-based processes. Currently, MBR's OPEX (0.158 USD/m3) is only slightly higher than that of biological contact oxidation (0.138 USD/m3). MBR also minimizes sludge production, reducing both treatment costs and associated disposal risks. MBR exhibit minimal concerns of excessive carbon emissions, with a carbon emission intensity (1.11 kg CO2eq·m−3), only slightly higher than biofilm-based processes (0.92 kg CO2eq·m−3). This study demonstrates that MBR is the valuable and practical solution for hospital wastewater treatment, as well as a preferred choice for upgrading existing facilities.

<b>In Silico Studies as Support for Natural Products Research</b>

It can be argued that in silico studies do not receive enough attention despite being a key part of addressing the limitations of our laboratory facilities, the high cost of chemicals, and the equipment required for wet laboratory activities. Natural product studies are demanding higher costs of chemicals, reagents, and varied laboratory facilities. This becomes a serious limitation in getting data from natural product studies. In silico studies use chemical structures as inputs as well as software and online web servers to generate data to support, predict, and validate wet laboratory activities. Interaction studies use computational tools to calculate binding energies and other associated properties. Predictions are based on the structure-activity relationships derived from previously conducted preclinical and clinical studies. As a main component of in silico studies, the physicochemical and pharmacokinetic properties of small molecules can be determined using online web servers such as SwissADME and ADMET web servers. An interaction study uses molecular docking software such as AutoDock, AutoDock vina, GOLD, and online servers such as SwissDock. Furthermore, the stabilities of complexes considered in interaction studies can be confirmed using molecular dynamics simulation software such as VMD. Prediction of activity spectra for substances (PASS) is widely used to predict biological activities for molecules based on MNA descriptors. In silico studies have played an important role in medicinal chemistry, pharmacology, and related research for screening, interaction studies, prediction, and other related purposes. Results of in silico predictions will not be far from wet lab activities as in most cases these studies consider previously attempted clinical and preclinical biological activities. Some examples are presented here to encourage the use of in silico studies. Received: 15 July 2024 | Revised: 27 August 2024 | Accepted: 25 Ocotber 2025 Conflicts of Interest The authors declare that they have no conflicts of interest to this work. Data Availability Statement The data that support this work are available upon reasonable request to the corresponding author. Author Contribution Statement Fekade Beshah Tessema: Conceptualization, Methodology, Writing - original draft, Visualization. Tilahun Belayneh Asfaw: Validation, Writing - review & editing. Mesfin Getachew Tadesse: Resources, Visualization, Supervision. Yilma Hunde Gonfa: Validation, Writing - review & editing. Rakesh Kumar Bachheti: Resources, Visualization, Supervision.

Cost-effectiveness analysis of chemical treatment with drones for Oncomelania hupensis control in marshland and lake areas

To evaluate the molluscicidal effect and cost of spraying molluscicides with drones against Oncomelania hupensis snails in marshland and lake areas, so as to provide new insights into field snail control in China. A marshland and lake setting measuring approximately 12 000 m2 was selected in Wanzhi District, Wuhu City on June 2023 as the test field, and assigned to four groups, of 3 000 m2 in each group. Environmental cleaning was not conducted in groups A or B, which were given 5% niclosamide ethanolamine salt granules sprayed with knapsack-type sprayers and drones at a dose of 40 g/m2, and environmental cleaning was conducted in groups C and D, which were given 5% niclosamide ethanolamine salt granules sprayed with drones and knapsack-type sprayers at a dose of 40 g/m2, respectively. O. hupensis snails were surveyed before chemical treatment and 1, 3, 5, 7, 14 days post-treatment. The uniformity of chemicals was determined on the day of treatment, and the snail mortality, corrected snail mortality and density of living snails were calculated and compared among groups. The cost of molluscicides, labor fees of environmental cleaning and chemical treatment and cost of equipment were calculated, and the cost for a 1% reduction in the mean density of living snails was calculated 14 days post-treatment. The mean densities of living snails and mortality rates of snails were 1.82 to 2.85 snails/0.1 m2 and 1.41% to 2.94% in groups A, B, C and D before chemical treatment, and the mortality and corrected mortality of snails were 55.75%, 49.32%, 85.94% and 87.50%, and 55.00%, 48.47%, 85.70% and 87.29% in groups A, B, C and D 14 days post-treatment. There was a significant difference in the mortality of snails among the four groups 14 days post-treatment (χ2 = 38.735, P < 0.005), and there was a higher snail mortality in Group D than in Group A (χ2 = 16.876, P < 0.005), and higher in Group C than in Group B (χ2 = 20.508, P < 0.005). The density of living snails reduced by 55.00%, 43.94%, 90.43% and 87.14% 14 days post-treatment relative to pre-treatment in groups A, B, C and D, respectively. The test for uniformity of chemicals showed that the mean dose of molluscicides were 57.34, 55.21, 40.19 g/m2 and 32.37 g/m2 in groups A, B, C and D, respectively, and the minimal standard deviation (7.07) and coefficient of variation (0.18) of mean doses were seen in Group C. The costs for chemical treatment were 0.33 Yuan in groups A and B and 1.53 Yuan in groups C and D, respectively. The costs for a 1% reduction in the mean density of living snails were 17.82, 22.47, 50.73 Yuan and 52.56 Yuan in groups A, B, C, and D 14 days post-treatment, respectively. The molluscicidal effect and cost of spraying 5% niclosamide ethanolamine salt granules with drones are comparable to manual spraying, and chemical treatment with drones are high in uniformity of molluscicides, time- and labor-saving, and feasible for applications in complex environments, which deserves widespread applications in the field of snail control.

Advances in Monazite Decomposition Technologies: Proposed Potential Direction for the Sodium Hydroxide Leaching Context

Abstract: The current understanding and development of monazite decomposition technology using sodium hydroxide are examined. Most previous assessments have primarily focused on the post-leaching processing of monazite using sodium hydroxide, including processing steps to produce the total rare earth oxide product. However, the initial leaching process of monazite with alkali solution proves to be highly significant in practice. It presents numerous problems, such as the requirement for fine grinding of the ore down to below 45 microns, substantial alkali excess, and extended reaction times to achieve the desired efficiency. These requirements result in increased energy, chemical, and equipment costs. This article is focused on discussing the leaching conditions of monazite with alkali solution based on published literature, the problems associated with this process, the underlying reasons, newly proposed variations such as sodium hydroxide leaching under pressure and sodium hydroxide leaching in a heated ball mill, limitations of these variations, and unresolved issues. Furthermore, the manuscript introduces a novel technique, high-intensity ultrasound, to support the leaching process, which has been applied in technological cases. The discussion delves into the mechanisms of high-intensity ultrasound and its applicability in the monazite leaching process using sodium hydroxide.

Characterizing fluid delivery of targeted application devices for weed control

AbstractPrecision weed management in turfgrass and ornamental landscape systems is utilized to offset chemical costs, reduce nontarget plant injury, and control potential herbicide‐resistant weed escapes. Targeted application devices (TADs), sold as wands, dabbers, daubers, sponges, and so forth, are regularly marketed for use in turfgrass and ornamental landscape systems, but TAD use has been limited to nonselective herbicides due to limited information regarding their calibration and use. Five commonly utilized TADs were evaluated to test for variability in fluid output within a given device and between evaluated devices. Fluid output for all evaluated devices ranged 3.2–6.9 kL ha−1 and were higher than spray outputs typical of broadcast applications. High levels of variability were detected within and among specific devices. Variance of output from devices with large fluid reservoirs was driven by reservoir fill level, with more fluid output decreasing linearly as reservoir fill level decreased. Additionally, when airlock was not maintained during application, fluid output was ∼178% greater than when airlock was maintained. Average force, maximum force, contact time, and fluid output following 25 applications were measured from five TAD users. Contact time was highly correlated (R2 = 0.93) to fluid output, with fluid output increasing as contact time increased. Subsequent economic analysis indicated the maximum percentage weed coverage ha−1 at which TAD use is economically equivalent or less than broadcast application is 3%, 8.1%, 4.3%, and 0.1% with iron HEDTA (hydroxyethlethydiaminetriacetate), acetic acid, methiozolin, and glyphosate, respectively. These data indicate the primary sources of TAD output variability are reservoir fluid fill level, reservoir airlock, and duration of application.

Understanding Citrus Growers Views on Protection Problems and Mitigation Strategies in Punjab, Pakistan

Increasing population pressure necessitates greater food production for a sustainable future, yet the prevalence of insect pests and diseases intensifies competition for critical resources. Pakistan has recorded substantial losses due to disease infestations, particularly affecting citrus crops. Citrus fruits are among the most widely cultivated and economically important agricultural commodities globally. However, s. However, various pests, diseases, and environmental factors significantly impact the production and quality of citrus fruits. This study aims to comprehensively analyze the major insects, diseases, and other factors that affect the protection of citrus crops, as well as the strategies that growers employ to mitigate these challenges. Therefore, the present study explored the major diseases, insects, and other factors affecting citrus protection. One hundred fifty respondents were selected using a Multistage random sampling technique under a survey-based research design. Findings indicate that most of the respondents were above the age of 40, and a significant portion of the population has education above the matriculation level. Citrus fruit fly, citrus leaf miner and psylla were the major insects affecting citrus protection. Citrus white fly, citrus caterpillar, citrus red scale, and citrus black fly also harm the citrus orchards. Findings also indicate that the major diseases affecting citrus protection were Citrus Canker, Gummosis, Citrus Melanose and Citrus Scab. Moreover, the study revealed that awareness about advanced protection practices, incomplete knowledge regarding the identification of insects and diseases, high cost of chemicals, poor quality of pesticides and unwise application of spraying were the major factors affecting citrus protection. This study also identifies that the coping strategies adopted by the growers to protect citrus were IPM practices, chemical control, biological control, insect control nets, use of resistant varieties, crop rotation and crop insurance.

Artificial intelligence-driven control for enhancing carbon dioxide-based wastewater pH regulation in tubular reactor

Alkaline wastewater treatment using carbon dioxide can reduce chemical costs and provide a safer alternative to traditional methods. However, complex gas-liquid reactions and narrow operating pH ranges present challenges. This research develops an artificial intelligence-driven control system for treating alkaline wastewater using carbon dioxide in a bench-scale tubular reactor. The proposed control system employs an inverse neural network to regulate the carbon dioxide gas based on the desired setpoint, along with a Smith predictor and a linear controller to compensate for natural delays, model mismatches, and pH disturbances. The inverse neural controller was trained using experimental data from a bench-scale reactor pH treatment of synthetic alkaline wastewater and verified on real influent from an electroplating wastewater treatment plant. The results show that the proposed method efficiently enforces the desired reactor outlet pH setpoint with up to 51.36% faster settling time than a proportional-integral controller while improving pH-adjusting efficiency by 72.24%.

Sustainable agriculture made easy: CETARA-NF's self-certification

Consumers can receive guarantees through the certified evaluation tool of agriculture resources analysis of natural farming (CETARA NF) without having to deal with costly third-party certification's entry obstacles or complex participatory guarantee systems. The purpose of this study is to examine the reasons for farmers' engagement in CETARA-NF as well as their experiences and results. 400 farmers randomly interviewed from 4 agroclimatic zones using the well-structured questionnaire from a 135,000 certified farmers list. Most farmers fall under the Two Star category (61.5 %), followed by One Star (28.5 %) and Three Star (10 %). The findings imply that 61 per cent of farmers are transitioning towards natural farming as these farmers have minimised or eliminated the chemical use in their farming practices. Significant factors of adoption for this certification system were increased marketed quantity, chemical fertiliser cost and no certification cost. Also, market access (Rank 1), no cost of certification (Rank 2) and women friendly (Rank 3) recognized as the major advantages of this certification. CETARA-NF can be an alternative certification solution for smallholders by securing the integration of grassroots agroecological cooperation and customs inside natural farming systems, thereby overcoming certification barriers.

Simultaneous alkali recovery, coagulant recycling and organics removal from textile wastewater via membrane electrochemical system

The membrane electrochemical reactor (MER) achieved synergistic textile wastewater treatment, alkaline solution recovery and magnesium coagulant recycling by the one-time addition of magnesium salt to the anode, solving the problems of reagent wastage and increased wastewater salinity caused by the continuous addition of chemicals in traditional treatments. In this study, the rapid adsorption and precipitation (within 3 min) of DB-86 in the cathode chamber by the magnesium coagulant were stimulated by the hydrophobicity of DB-86, resulting from the relatively dispersed localization of negative charges on the H atoms on the molecule’s surface. The precipitated solids in the cathode effluent were recovered through an ultra-filtration process and recycled to the anode for dissolution. Effective mineralization of dyes was achieved by anode electrolysis, generating large amounts of active chlorine on its surface as an indirect oxidant, resulting in 80.15 % TOC removal after 30 min. Operational stability tests were conducted using both simulated dye wastewater and actual textile wastewater. The decolorization efficiency of the system remained at 99.9 % for simulated dye wastewater and 99.5 % for actual textile wastewater after six cycles of long-term operation. Magnesium hydroxide is re-dissolved at the anode, then passes through the ion exchange membrane into the cathode for recycling. Loss of magnesium ions occurs only at the ultra-filtration surface, achieving recovery efficiencies exceeding 95 % for simulated dye wastewater and 80 % for actual textile wastewater. The MER/Mg system in this study achieved rapid coagulation and mineralization of DB-86, along with efficient recycling of Mg2+ ions, thus avoiding wastage of chemical sludge and reagents, and reducing chemical consumption and treatment costs.

A Study of CO2 Storage in Bimodal Carbonate Aquifer Rocks: Challenges and Enhancement through Foaming

Summary In carbonate rock reservoirs, the presence of dual-pore systems, characterized by two distinct pore size distributions, plays a crucial role in gas storage in saline aquifers. However, comprehensive research on the impact of bimodal porosity on CO2 storage in such reservoirs is lacking. This study explores CO2 storage efficiency in carbonate aquifer rocks with bimodal porosity. Petrographic examination, capillary pressure measurements, and nuclear magnetic resonance (NMR) T2 profiling revealed two distinct and interconnected pore systems with equal effective porosity proportions. While both systems facilitated fluid flow, the micropores had a high capillary entry pressure (&amp;gt;100 psi). Coreflood experiments showed gas displacement efficiencies below 50%, primarily in larger pores, with only 49–58% of these large pores (20–28% of total pores) storing injected gas through residual trapping after water imbibition. To address this challenge, CO2 was foamed using a foaming agent to enhance viscous forces and overcome capillary forces. This resulted in significant improvements, including a 31% increase in displacement efficiency and a 28% increase in residual gas. NMR analysis revealed effective redirection of CO2 into smaller pores when foam was applied. In another experiment on a sample with a different pore geometry, the use of nanoparticles to strengthen foam increased sweep efficiency by up to 117%, with a corresponding increase of up to 169% in residual trapping. While the use of foam entails additional operational expenses, we contend that the economic viability of foam technology for CO2 storage hinges on a rigorous cost-benefit analysis that weighs increased storage capacity/security against chemical costs. Such analysis should also consider the time, cost, and uncertainty associated with developing additional storage sites. Furthermore, improved site selection criteria in carbonate rocks are needed, including a predictive model for T2 cutoff to identify aquifers with excessive micropores and avoid them during site selection. While fractured porosity is not within the scope of this study, it is expected that foam can equally improve sweep and trapping efficiencies in naturally fractured carbonate rocks.

Impact of planting density and shoot thinning on alstroemeria flowering, soil attributes and cost economics

A field experiment was conducted to assess the impact of various planting densities and levels of shoot thinning on cut flower yield, quality, soil chemical properties and cost economics in the commercially cultivated alstroemeria cultivar 'Capri'. The experiment involved three planting densities (4, 6 and 8 plants/m2) along with three shoot thinning levels (10 %, 20 % and 30 %). It was observed that higher planting density (4 plants/m2) promoted the length of cut stem, early bud formation, and flowering, optimal quality parameters, including maximum stem thickness, cut stem weight, floret quantity/stem, floret size, number of flowering stems/plant (yield) and vase life. Exclusive use of higher vegetative mass removal (30 % shoot thinning) was found to improve quality parameters such as the length of cut stem, number of flowering stems, stem thickness, weight of cut stem, floret quantity/stem, floret size, vase life, and early flowering. Soil samples were collected from each treatment and the consequent lab analysis revealed that the lower planting density and shoot thinning level resulted in maximum soil organic carbon, nitrogen, phosphorous and potassium content. In conclusion, planting density of 4 plants/m2 and 30 % shoot thinning emerged as the optimal combination for enhancing quantitative parameters in commercial alstroemeria cultivation. The study underscores the importance of strategic planting practices and vegetative mass management for maximizing yield and quality in alstroemeria production, along with ensuring higher economic returns.

An energy efficiency and cost analysis of utilizing high-intensity profile UVC systems on air handling unit under cool-humid climate

The feasibility of the ultraviolet germicidal irradiation (UVGI) application has been proven over the past few decades, especially in disinfection performances; however, a small number of studies were found that explored the energy efficiency improvement and cost savings of real buildings by implementing the UVC systems on cooling coils. The goal of this study is to verify the energy efficiency improvements and cost savings of AHU in a real building environment by removing biofilms on the cooling coil surfaces with the UVC irradiation techniques that can provide higher lamp output (300 μW/cm2) as well as higher intensity levels (1000–4000 μW/cm2) on the cooling coil surfaces. A series of experiments were conducted in an AHU in a medical center located in Michigan, US, to estimate energy efficiency improvement of cooling coils, chiller, and fan with UVC application. The results show that after 7 weeks of UVC operation increased coil overall enthalpy-based thermal conductance by 15.62 %, achieved chiller-side energy savings by up to 28.2 %, reduced pump energy by 32.1 %, and fan energy by 17.7 %. A return on investment (ROI) based only on energy savings is estimated to be 43 % and has a payback period of 2.32 years. When the labor, chemical, and water-saving costs for coil cleaning were included, the ROI was increased to 49 % and reduced the payback period to 2.04 years. When it comes to UVC's disinfection performances, six pathogens showed a more than 99 % removal rate while Klebsiella pneumoniae and Clostridium difficile showed a relatively lower 94 % removal rate.

Aqueous colloid flow batteries with nano Prussian blue

Flow battery is a safe and scalable energy storage technology in effectively utilizing clean power and mitigating carbon emissions from fossil fuel consumption. In the present work, we demonstrate an aqueous colloid flow battery (ACFB) with well-dispersed colloids based on nano-sized Prussian blue (PB) cubes, aiming at expanding the chosen area of various nano redox materials and lowering the cost of chemicals. Taking advantage of the two redox pairs of PB, the developed all-PB cell employing a low-cost dialysis membrane with the synthesized PB on both sides displays an open-circuit voltage (OCV) of 0.74 V. Moreover, when paired with an organic tetra pyridine macrocycle the cell with PB as positive electrolyte exhibits an OCV of 1.33 V and a capacity fade rate of 0.039 %/cycle (0.8 %/day). Redox-active colloids exhibit enduring physicochemical stability, with no evident structural or morphological changes after extensive cycling, highlighting their potential for cost-effective and reliable ACFB energy storage.