Daily Production Research Articles

Volatile organic compounds during routine production and planned shutdown of a petrochemical refinery: Emission characteristics, source and risk assessment

During the routine production and planned shutdown of a petrochemical refinery in China, ambient volatile organic compound (VOC) data were continuously determined by an online monitoring system, and VOC characteristics, source apportionment, and health risks were calculated based on those data. The data showed that the total VOC concentration emitted during the planned shutdown period was significantly higher than that under daily production conditions, especially the alkane concentration, which increased from 137.4 μg m−3 to 481.8 μg m−3. A source apportionment study was performed using a positive matrix factorization model based on VOC data collected during different sampling times. The contributions of petroleum refinery emissions increased from 63.8% during routine production to 79.4% during the shutdown period. In addition, carcinogenic and noncarcinogenic risk assessment revealed that workers could be under higher acute and chronic health risks during the shutdown and maintenance period than during the routine production of the refinery. The results also indicated that VOCs emitted during maintenance might have more influence on public health. Therefore, more attention should be paid to the emission characteristics and source apportionment of VOCs during planned shutdowns. This work provides valuable data that can help regulatory agencies formulate VOC control strategies during routine production and shutdown maintenance in petrochemical refineries.

Ca-MOF-Derived Porous Sorbents for High-Yield Solar-Driven Atmosphere Water Harvesting.

The development of high-yield, metal-organic framework (MOF)-based water harvesters in arid areas remains challenging due to the absence of effective strategies for enhancing water sorption capacity and kinetics. Herein, we presented a novel strategy for in situ fabrication of calcium chloride (CaCl2) decorated MOF-derived porous sorbents (PCC-42) through pyrolysis Ca-MOF and subsequently hydrochloric acid (HCl) vapor treatment process. The resulting PCC-42 sorbents exhibited a high water adsorption capacity of 3.04 g g-1 at 100% relative humidity (RH), outstanding photothermal performance, and rapid water uptake-release kinetics, surpassing most reported MOFs adsorbents. At 20, 30, 40, and 50% RH, PCC-42 demonstrated water uptake capacity of 0.45, 0.59, 0.76, and 0.9 g g-1, which represented an increase of 421 and 940% (at 20% RH) and 333 and 351% (at 30% RH) compared to Ca-MOF and CaCl2·2H2O, respectively. Approximately 80% of the adsorbed water in PCC-42 could be released under one sun within 50 min. Indoor water harvesting experiments demonstrated that PCC-42 is a promising adsorbent for various humidity environments. Additionally, outdoor solar-driven atmospheric water harvesting (AWH) tests revealed a high daily water production of 1.13 L/kgadsorbent under typical arid conditions (30-60% RH). The proposed strategy helps the design of high-performance adsorbents for solar-driven AWH in arid environments.

Uncovering genetic parameters and environmental influences on fertility, milk production, and quality in autochthonous Reggiana cattle

Reggiana is a local cattle breed from northern Italy known for its rusticity and profitability, due to the production of branded Parmigiano Reggiano cheese. To ensure the persistence of such profitability in the long term, an adequate breeding program is required. To this aim, in the present study we estimate the genetic parameters of the main productive and reproductive traits, and we evaluate the effect of genotype by environment interaction (GxE) on these traits using 2 environmental covariates: (1) productivity and (2) temperature-humidity index (THI). Milk, fat, protein, and casein yield were considered as daily production traits, whereas protein, fat, casein percentage, casein index, and somatic cell score were considered as milk quality traits. Finally, reproductive traits such as the number of inseminations, days open, calving interval, and calving-to-first-insemination interval were evaluated. Reggiana cattle produce an average of 19 kg of milk per day with 3.7% fat and 3.4% protein content and have excellent fertility parameters. Compared with other breeds, they have slightly lower heritability for production and quality for production traits (e.g., 0.12 [0.09; 0.15] for milk yield), but similar heritability for fertility traits. Milk, protein, and fat daily yields are highly correlated but negatively correlated with the percentage of protein, fat, and casein, whereas fertility traits have an unfavorable genetic correlation with daily production traits. When considering productivity, a consistent amount of variability due to GxE was observed for all daily production traits, somatic cell count, and casein index. A modest amount of GxE was observed for fertility parameters, while the percentage of solid content showed almost no GxE effect. A similar situation occurred when considering the THI, but no GxE interaction was observed for reproduction traits. In conclusion, this study provides useful information for the implementation of accurate selection plans in this local breed, accounting for environmental plasticity measured through the consistent GxE interaction observed.

Solar powered hybrid desalination system using a novel evaporative humidification tower: A numerical investigation

This research describes a hybrid solar desalination system that includes a humidification-dehumidification unit as well as a solar still unit. The current system is being studied numerically. A one-dimensional model of the important heat and mass exchanges, as well as the flow field, was built using the finite difference method. Freshwater productivity is calculated under various operating and weather conditions. The model has been modified to investigate the steady-state behavior of the system components. Four major parameters that have a significant impact on system water production are investigated: the feed flow rate of cooling water through the dehumidifier unit, the airflow rate, and the number and height of packing columns. According to the results, the proposed hybrid desalination system provides appropriate operational compatibility between HDH technology and solar energy. The system can provide a daily production of up to 35 liters per day. Increasing the number of packing columns results in a higher increase in fresh water productivity than increasing the height of the packing columns. The optimal air flow rate at a constant saline-water flow rate is obtained. For high airflow rates, the packing column height doesn't significantly affect the daily water production. System performance is investigated by four main parameters: gained output ratio (GOR), humidifier efficiency, exergy efficiency, and system efficiency. The system efficiency reached about 65% and the GOR reached 3.1. The humidifier’s efficiency varied between 50% and 75%. The maximum exergy efficiency reached about 5.2%.

Estimation of fracture half-length with fast Gaussian pressure transient and RTA methods: Wolfcamp shale formation case study

Accurate estimation of fracture half-lengths in shale gas and oil reservoirs is critical for optimizing stimulation design, evaluating production potential, monitoring reservoir performance, and making informed economic decisions. Assessing the dimensions of hydraulic fractures and the quality of well completions in shale gas and oil reservoirs typically involves techniques such as chemical tracers, microseismic fiber optics, and production logs, which can be time-consuming and costly. This study demonstrates an alternative approach to estimate fracture half-lengths using the Gaussian pressure transient (GPT) Method, which has recently emerged as a novel technique for quantifying pressure depletion around single wells, multiple wells, and hydraulic fractures. The GPT method is compared to the well-established rate transient analysis (RTA) method to evaluate its effectiveness in estimating fracture parameters. The study used production data from 11 wells at the hydraulic fracture test site 1 in the Midland Basin of West Texas from Upper and Middle Wolfcamp (WC) formations. The data included flow rates and pressure readings, and the fracture half-lengths of the 11 wells were individually estimated by matching the production data to historical records. The GPT method can calculate the fracture half-length from daily production data, given a certain formation permeability. Independently, the traditional RTA method was applied to separately estimate the fracture half-length. The results of the two methods (GPT and RTA) are within an acceptable, small error margin for all 5 of the Middle WC wells studied, and for 5 of the 6 Upper WC wells. The slight deviation in the case of the Upper WC well is due to the different production control and a longer time for the well to reach constant bottomhole pressure. The estimated stimulated surface area for the Middle and Upper WC wells was correlated to the injected proppant volume and the total fluid production. Applying RTA and GPT methods to the historic production data improves the fracture diagnostics accuracy by reducing the uncertainty in the estimation of fracture dimensions, for given formation permeability values of the stimulated rock volume.

Role of serotonin, estrogen, and TNF-α in the paroxetine-impaired steroidogenesis and testicular macrophages polarization.

Paroxetine, a selective serotonin reuptake inhibitor (SSRI) antidepressant, has caused male sexual dysfunction; however, the paroxetine mechanisms of action in testes are still unclear. Paroxetine serotonergic effects in testes were evaluated, focusing on steroidogenesis and the correlation between macrophages population and possible TNF-α-derived oxidative stress. We also verified whether the changes are reversible following treatment interruption. Adult rats received paroxetine (PG35 and PG65) or tap water (CG) for 35 days. PG65 was maintained without treatment for 30 more days. Intratesticular testosterone (IT), nitrite, and malondialdehyde concentrations were measured. To confirm serotonergic and estrogenic effects, Htr1b and Esr1 expressions were analyzed. The daily sperm production (DSP), frequency of abnormal seminiferous tubules (ST), SC number, ST area, and Leydig cells nuclear area (LCnu) were evaluated. TUNEL+ germ cells, M1 (CD68+ ), and M2 (Perls+ ) macrophages were quantified. 17β-HSD7, CYP19A1, NDRG2, oxytocin, TNF-α, and iNOS were evaluated by immunoreactions. Oxytocin and NDRG2 protein levels as well as Tnfa mRNA expression were also analyzed. The Htr1b downregulation in testes confirmed the paroxetine serotonergic effect. The testicular sections showed abnormal ST frequency, ST atrophy and reduction of DSP, LCnu, SC number and Perls+ macrophages. TUNEL+ germ cells and LC were associated with strong NDRG2 immunoexpression. Paroxetine reduced IT levels and 17β-HSD7 immunoexpression in parallel to increased CYP19A1, oxytocin, TNF-α and iNOS. Esr1 and Tnfa overexpression and increased number of CD68+ macrophages were also observed together with high nitrite and malondialdehyde levels. Most parameters were not recovered in PG65. Paroxetine serotonergic effect impairs LC steroidogenesis, via aromatization, increasing estrogen/testosterone ratio, which in turn upregulate NDRG2, promoting apoptosis, and impairing sperm production. Serotonin-estrogen pathways may be responsible for M2/M1 polarization, Tnfa upregulation, and induction of oxidative stress. The unrecovered testicular changes after treatment discontinuation are due to persistent paroxetine serotonin/estrogen effects.

Synthetic of functionalized magnetic titanium-based metal–organic frameworks to efficiently remove Hg(Ⅱ) from wastewater

The rapid development of process technology has led to rapid daily industrial production, which also produced a large amount of waste liquid. At the same time, the existing treatment technology cannot keep up with the demand, resulting in the malicious destruction of the environment by wastewater, especially mercury-containing wastewater was very harmful. Effective means of removing mercury ions need to be found. With magnetic ferric oxide as the core and titanium-based metal–organic frameworks as the shell, a new type of magnetic adsorbent (BTA-MIL-125(Ti)@Fe3O4) was synthesized. Materials were tested by multiple characterization methods and multiple sets of experiments. At optimal pH 6, the removal rate in 100 ppm Hg(Ⅱ) was as high as 95.8%. The theoretical adsorption capacity was 615 mg/L. Isothermal experiments, kinetic experiments and thermodynamic experiments have respectively verified that the material was a kind of adsorption material with self-emission heat based on chemical action and synergistic adsorption with Hill model. By simulating the immunity of a variety of ions (Cu, Zn, Mg, Ni, Cd), the material itself also exhibited a very high affinity for Hg(Ⅱ). The results of five high-cycle stable adsorption proved the repeatable stability of the material itself. Various characterization methods have also shown that nitrogen and sulfur-containing groups chelated with Hg(Ⅱ). All of the above was enough to show that the BTA-MIL-125(Ti)@Fe3O4 was a magnetic adsorption material with excellent performance and great prospects.

Effects of Supplementation of a Mycotoxin Mitigation Feed Additive in Lactating Dairy Cows Fed Fusarium Mycotoxin-Contaminated Diet for an Extended Period.

Fusarium mycotoxins are inactivated by rumen flora; however, a certain amount can pass the rumen and reticulum or be converted into biological active metabolites. Limited scientific evidence is available on the impact and mitigation of Fusarium mycotoxins on dairy cows' performance and health, particularly when cows are exposed for an extended period (more than 2 months). The available information related to these mycotoxin effects on milk cheese-making parameters is also very poor. The objective of this study was to evaluate a commercially available mycotoxin mitigation product (MMP, i.e., TOXO® HP-R, Selko, Tilburg, The Netherlands) in lactating dairy cows fed a Fusarium mycotoxin-contaminated diet, and the repercussions on the dry matter intake, milk yield, milk quality, cheese-making traits and health status of cows. The MMP contains smectite clays, yeast cell walls and antioxidants. In the study, 36 lactating Holstein cows were grouped based on the number of days of producing milk, milk yield, body condition score and those randomly assigned to specific treatments. The study ran over 2 periods (March/May-May/July 2022). In each period, six animals/treatment were considered. The experimental periods consisted of 9 days of adaptation and 54 days of exposure. The physical activity, rumination time, daily milk production and milk quality were measured. The cows were fed once daily with the same total mixed ration (TMR) composition. The experimental groups consisted of a control (CTR) diet, with a TMR with low contamination, high moisture corn (HMC), and beet pulp; a mycotoxins (MTX) diet, with a TMR with highly contaminated HMC, and beet pulp; and an MTX diet supplemented with 100 g/cow/day of the mycotoxin mitigation product (MMP). The trial has shown that the use of MMP reduced the mycotoxin's negative effects on the milk yield and quality (protein, casein and lactose). The MTX diet had a lower milk yield and feed efficiency than the CTR and MMP HP-R diets. The MMP limited the negative effect of mycotoxin contamination on clotting parameters, mitigating the variations on some coagulation properties; however, the MMP inclusion tended to decrease the protein and apparent starch digestibility of the diet. These results provide a better understanding of mycotoxin risk on dairy cows' performances and milk quality. The inclusion of an MMP product mitigated some negative effects of the Fusarium mycotoxin contamination during this trial. The major effects were on the milk yield and quality in both the experimental periods. These results provide better insight on the effects of mycotoxins on the performance and quality of milk, as well as the cheese-making traits. Further analyses should be carried out to evaluate MMP's outcome on immune-metabolic responses and diet digestibility.

Combining offshore wind and wave energy to supply a big size desalination plant

This research analyses the feasibility of supplying a large size desalination energy demand by marine renewables. The case study is Las Palmas III seawater desalination plant, the largest desalination plant in the Canary Islands (Spain), which is located in the northeast of the island of Gran Canaria. Its average daily water production is 62,614 m³/day, consuming a total of 90,669.52 MWh/year. A constant energy production is needed for the optimal plant operation which raises the possibility of using different renewable technologies in order to reduce the energy fluctuations. In this case, the sea and its wind and wave energy resources are key technologies for supplying desalination plants near the coast. For this reason, different configurations have been simulated combining both technologies and analyzing their pairing in hourly terms to achieve a more stable energy production. The proposed methodology contemplates the identification of the hotspot for the technologies location in terms of environmental constraints and resource assessment (both wind and waves). The subsequent selection of the wind turbine and the wave converter and the energy coverage evaluation. Results tried to establish if the combination of offshore wind and wave energy improves the demand coverage in overall terms and in terms of seasonal match.

Distributed Energy Grid-Connected Dense Data Forecasting Technology Based on Federated Learning

Photovoltaic power generation system is one of the main clean energy power generation systems at present, which plays an important role in daily production and life. However, the photovoltaic power generation system is easily affected by various factors, and the output power will be unstable in the practical application process, which will affect the power generation efficiency. In this paper, a prediction method of distributed energy grid-connected dense data based on federated learning is constructed. This method can not only realize the short-term prediction of distributed photovoltaic power generation data, but also ensure that the data can be encrypted and modeled, thus solving the “digital island” problem. The model evaluation shows that the method in this paper performs well in short-term photovoltaic power generation prediction, and it can predict the short-term power generation of different photovoltaic power stations with high prediction accuracy. This method is of great significance to improve the management and scheduling ability and energy utilization rate of distributed photovoltaic power generation systems.

Daily fresh water production from Malaysia’s urban atmosphere using 6 thermoelectric cooling units

Extracting fresh water from Malaysia’s atmosphere which stores a wealth of water can be conducted via the air condensation. In this study, a miniature atmospheric water generator (AWG) system named Mini-AWG was designed and constructed using 6 thermoelectric cooler (TEC) units, a mesh-shaped air filter and a ventilation fan. Subsequently, the Mini-AWG was experimented for several days under Malaysia’s outdoor climate at River Engineering and Urban Drainage Research Centre (REDAC) in Universiti Sains Malaysia (USM) which is located in the urban area of Nibong Tebal. The objectives of this work are to develop a miniature AWG system using 6 TEC units to generate water by vacuuming the urban outdoor Malaysia’s atmosphere into the system, determine the impacts of the humidity rates and ambient temperatures values on the quantity of water production and analyze the quality of the water generated by the Mini-AWG system. The daily percentages of relative humidity, rates of ambient temperatures and the volume of produced water were measured which was resulted that the hourly amount of produced water by Mini-AWG were proportional to the hourly percentages of relative humidity, though they had inverse relationship with the hourly rates of ambient temperatures. The Mini-AWG produced the maximum daily fresh water of 0.355 litres experimentally in 12 hour-period in the day. According to the various hourly rates of relative humidity ranged between the least of 46% and the peak of 75% in Malaysia from morning to night, an equation of y= 1.3136x + 16.936 with R2 of 0.8901 was attained experimentally to project the amount of water production of Mini-AWG, where Y and X were designated as the percentage of humidity and the amount of water production, respectively. The examined quality parameters of the water produced from Mini-AWG was in compliance with the World Health Organization (WHO) and Malaysia class I drinking water standards.

Usefulness of the total and differential somatic cell count based udder health group concept for evaluating herd management practices and udder health in dairy herds.

Subclinical mastitis and associated economic losses are a steady challenge in the dairy industry. The combination of the well-established somatic cell count (SCC) parameter and the new differential SCC (DSCC) opens up the possibility to categorise cows into four different udder health groups (UHG) based on results from a single milk recording/dairy herd improvement (DHI) test: UHG A: healthy/normal, ≤200,000 cells/mL and DSCC ≤65 %; B: suspicious, ≤200,000 cells/mL and DSCC >65 %; C: (subclinical) mastitis, >200,000 cells/mL and DSCC >65 %; D: chronic/persistent mastitis, >200,000 cells/mL and DSCC ≤65 %. The objectives of this study were to investigate 1) herd management practises among herds in different UHG categories and 2) herd performance parameters depending on the proportion of cows in UHG A. A total number of 41 herds in Styria, Austria, and Thuringia, Germany, were visited and interviewed for the first part of the study. The herds were categorised into 3 UHG categories depending on the proportion of cows in UHG A: I =>65 %; II =55-65 %; and III =<55 %. Those with good udder health and best herd performance (+9 % milk yields, +11 % longevity, -35 % antibiotic treatments) applied distinct preventive measures, in particular excellent cubicle management and early antibiotic treatment (P<0.05 each). However, preventive measures were applied to a lower extent in other herds. Herds were categorised differently using the UHG concept compared to SCC alone as the UHG-based categorisation allowed to clearer distinguish herds with medium-good from those with good udder health. A total number of 129,812 regular milk recording/DHI test day results of 890 Austrian and 183 German herds was used for the second part of the study. Results revealed a trend of increasing daily production as proportions of cows in UHG A increase. In conclusion, the UHG concept allowed clearer distinction of herds with good, medium-good, and poor udder health and could be used to promote practises leading to better animal health, less antibiotic treatments, and higher milk quality.

Weather effect and cost analysis of solar adsorption desalination system using MIL-101(cr) – Graphite oxide composite material

Solar-powered adsorption desalination systems (ADSs) are a significant way to provide clean and fresh water using environmentally friendly adsorbent materials. This work presents an innovative investigation of solar-driven ADS's performance and cost analysis using a metal–organic framework MIL-101(cr) with and without a 2D graphite oxide (GO) material. The investigation is conducted over a complete year using lumped modeling by MATLAB and TRNSYS software. The production cost of desalinated water is evaluated using solar energy and waste heat sources. It is found that the effect of adding 2D-GO to MIL-101(cr) is positive on the isotherms and negative on the kinetics properties; hence the overall performance of MIL-101(cr) and MIL-101(cr) + GO was very close with an average difference of 2%. Optimum-specific daily water production and gain output ratio achieved at summer 24 m3/ton-day and 0.7, respectively, using MIL-101(cr). The cost is estimated to be 4.7 $/m3 using solar energy and 1.01 $/m3 using waste heat. The performance parameters indicate the effectiveness of MIL-101(cr) in solar/waste heat-driven ADS at a reasonable cost to remote areas.

Immobilized Cell Bioreactor Industrialization in the Development of an Innovative Optical Biosensor Technology

This commentary shows the development of a new optical biosensor, based on cell immobilization of Pseudomonas Fluorescens HK44, in nano and micro-tubular cellulose (TC) and a mixture of carbohydrate nanotubes (CHNTs) and carbohydrate micro-tubes (CHMTs). Methodology follows, this biocatalyst can be industrialized with the use of a single tank immobilized cell bioreactor (ICB). A techno-economic analysis was conducted within the framework of it by designing a process flow sheet with mass and energy balance. According to its case study, the investment is 227,800 euros, and the daily production cost is 1434 euros, with a maximum daily added value of 25,000 euros. The discussion revealed that novel research proposals and a novel study concept are being developed in the field of biosensors. The results are supported by papers published on ICB area development. The problem that leads to this commentary is industrialization of ICB, in the case of a simple biosensor development using immobilized cells and it is the objective.

High yielding cows metabolism peculiarities under climate change conditions with the use of feed additive with protein protected from rumen degradation

The research relevance is determined by the problem of thermal load on the body of dairy cows by increasing the content of protein protected from breakdown in the rumen. The research aims to determine the metabolism and level of delivery of various forms of protein and energy to the body of highly productive cows in the diets of cows in the second half of lactation under conditions of climate change. Research methods include zootechnical (assessment of feed intake, rationing, selection of groups, organisation of the experiment, determination of milk production), biochemical (determination of the content of basic nutrients in feed, milk quality indicators), statistical, and mathematical. The compensation of protein in the diet of high-yielding cows under climate change conditions was carried out using the protein feed additive TEP-mix with protein protected from rumen breakdown. It has been proven that its inclusion in the cow’s diet can increase average daily milk production by 9.1% in the cold season (0-10°C) and by 28.0% in the summer (21-36.4°C). In addition, the fat and protein content in milk increased in cows receiving the high-protein feed additive TEP mix. It was found that the increase in protein nutrition of cows from 23.18% to 33.53% with the use of the feed additive TEP-mix with protein protected from scar breakdown ensures a reduction in the impact of climate change on the metabolism of dairy cows. Thus, it has been proved that the use of specific protein feed sources that regulate the level of non-cutting protein in the diet can be considered a factor in combating heat stress and increasing milk production of dairy cows throughout the physiological cycle of lactation, including in extreme conditions of high temperatures

The influencing factors of carrying capacity of urban electricity infrastructure: Case study of six Chinese mega-cities

As one of important urban infrastructures, urban electricity infrastructure provides electrical resources, which people need in urban daily production and life. Its carrying capacity is vital to the normal operation of urban economic and social systems and affected by many different factors. Investigating the influencing factors of carrying capacity of urban electricity infrastructure is beneficial for grasping its operational status and improving its service level. This paper takes six Chinese mega-cities as examples to analyze the influencing factors of carrying capacity of urban electricity infrastructure by constructing panel regression model. This model is helpful for judging the impact degrees of different factors and finding the main influencing factors. It is an important method of grasping the common reasons of levels of carrying capacity of urban electricity infrastructure of different cities, which provides a major way for obtaining scientific and objective results. The results show that urban industrial structure has the most significant impact on carrying capacity of urban electricity infrastructure; per capita disposable income, per capita output, population density, proportion of non-agricultural population and capital input of urban electricity infrastructure also have significant influences to it. The carrying capacity of urban electricity infrastructure is mainly affected by urban economic and population factors. According to the research results, three policy implications are put forward to raise carrying capacity of urban electricity infrastructure.

Quantitative microbial spoilage risk assessment caused by fungi in sports drinks through multilevel modelling

The risk of fungal spoilage of sports drinks produced in the beverage industry was assessed using quantitative microbial spoilage risk assessment (QMSRA). The most relevant pathway was the contamination of the bottles during packaging by mould spores in the air. Mould spores' concentration was estimated by longitudinal sampling for 6 years (936 samples) in different production areas and seasons. This data was analysed using a multilevel model that separates the natural variability in spore concentration (as a function of sampling year, season, and area) and the uncertainty of the sampling method. Then, the expected fungal contamination per bottle was estimated by Monte Carlo simulation, considering their settling velocity and the time and exposure area. The product's shelf life was estimated through the inoculation of bottles with mould spores, following the determination of the probability of visual spoilage as a function of storage time at 20 and 30 °C using logistic regression. The Monte Carlo model estimated low expected spore contamination in the product (1.7 × 10−6 CFU/bottle). Nonetheless, the risk of spoilage is still relevant due to the large production volume and because, as observed experimentally, even a single spore has a high spoilage potential. The applicability of the QMSRA during daily production was made possible through the simplification of the model under the hypothesis that no bottle will be contaminated by more than one spore. This simplification allows the calculation of a two-dimensional performance objective that combines the spore concentration in the air and the exposure time, defining “acceptable combinations” according to an acceptable level of spoilage (ALOS; the proportion of spoiled bottles). The implementation of the model at the operational level was done through the representation of the simplified model as a two-dimensional diagram that defines acceptable and unacceptable areas. The innovative methodology employed here for defining and simplifying QMSRA models can be a blueprint for future studies aiming to quantify the risk of spoilage of other beverages with a similar scope.

Investigation of the energetic, exergetic performance, environmental, economic, and hydrogen production analyses of PV-T for increasing surface areas and mass flow rates compared to PV

This study investigated the energetic and exergetic efficiencies and environmental and economical, electricity and hydrogen production analyses of water-cooled photovoltaic thermal (PV-T) solar collectors and PV. For this purpose, simulations were made with Engineering Equation Solver (EES) for PV-T and PV systems with 3 different areas (A1 = 1 m2, A2 = 3 m2, and A3 = 5 m2). Also, PV-T was cooled with three mass flow rates (m˙1=0.01 kg/s, m˙2=0.03 kg/s and m˙3=0.05 kg/s). Simulations were made for each hour from 7 a.m. to 7 p.m. for a day in July. As a result, the maximum daily electricity production of the PV-T for the A1, A2, and A3 were found for m˙3=0.05 kg/s as 3.791 MJ, 11.227 MJ, and 18.49 MJ. The maximum daily electricity production PV for the A1, A2, and A3 were found as 3.305 MJ, 9.916 MJ, and 16.527 MJ. The highest energetic efficiency of the PV-T was found for m˙3=0.05 kg/s as 60.52%, 58.87%, and 57.19%. The highest exergetic efficiency of the PV-T was found for m˙1=0.01 kg/s as 16.77%, 16.89%, and 16.61% for A1, A2, and A3. The highest energetic and exergy efficiency of the PV was found as 14.40% and 15.44%. When PV-T cooled with a maximum of m˙3=0.05 kg/s, the system saved a total of 0.8475 kg 2.4799 kg, and 4.0368 kg CO2 for A1, A2, and A3. The daily carbon savings of the PV were found as 0.3709 kg, 1.1128 kg, and 1.8545 kg for the same areas. The highest hydrogen production of the system with PV-T was found for m˙3=0.05 kg/s as 18.5677 g 54.9966 g and 90.566 g for A1, A2, and A3. The daily hydrogen production of the system with the PV were found as 16.1884 g, 48.5637 g and 80.9418 g for A1, A2, and A3. The highest monthly economic contribution of the system with PV-T was found for m˙3=0.05 kg/s as 360.22 TL, 1047.22 TL and 1693.65 TL for A1, A2, and A3. Also, daily economic contribution of the system with PV was found 73.67 TL, 221.01 TL and 368.35 TL for same areas. It was found that the production performance of the system increased as the cooling flow rate increased and the PV-T area decreased. Also, the thermodynamic efficiency, the electricity and hydrogen production, economic contribution and carbon savings of the system with PV-T are found higher than the system with PV in all combinations.

Energy Storage Potential Needed at the National Grid Scale (Poland) in Order to Stabilize Daily Electricity Production from Fossil Fuels and Nuclear Power

With the increasing share of renewable sources in the energy mix, there is a need to balance energy production from weather-dependent sources, such as wind turbines and photovoltaics. This is also a current global trend associated with climate policy. In Poland, there has been a significant increase in energy production from renewable sources, leading to a duck curve phenomenon mainly in the case of photovoltaics, which requires balancing this production through various measures. One possible way to achieve this is energy storage installation. This article identifies the need for energy storage to ensure the stability of electricity production from low-flexibility sources like coal-based power plants. For this purpose, a methodology has been developed to determine the daily minimum energy storage capacities which would also allow for the integration of other stable (though less flexible) energy sources, such as nuclear power. In the case of Poland, energy storage has been estimated to require, as a median value, approximately 6 GWh of additional storage capacity, which is equivalent to twice the planned capacity of the Młoty Pumped Storage Power Plant.

Long-term modeling of the performance of a solar still with phase-change material

Solar stills may be a small-scale and eco-friendly alternative to conventional, large-scale, and fossil-fuel-powered desalination plants due to growing worldwide water scarcity. However, solar stills suffer from low productivity which can be increased by optimizing the water mass and phase-change material (PCM) mass. Therefore, this paper aims at investigating the influence of water mass and PCM mass on the long-term performance of a solar still (SS) located in Poland. The long-term performance of SS is an important issue, as people need desalinated water all year round. Simultaneously, there is a limited number of publications concerning this issue in the open literature as most papers focus on the SS performance in a short-term period, usually no more than a couple of days. Therefore, research on the effect of water and PCM mass on SS performance in the context of long-term operation under various weather conditions, which is done in this work, is valuable and necessary. Additionally, this is the first time when the SS is investigated under Polish weather conditions. The study is carried out by conducting a theoretical analysis based on the mathematical modeling of the solar still. The mathematical model describing the thermal processes in the SS is established and validated using the experimental results. The results of simulations for average days for each month show that the maximum productivity of the SS is in July (3039 mL/m2/day with 5 kg of water), while the lowest is in October (900 mL/m2/day). The greatest annual SS productivity is 488.8 L/m2/year in Poland and is achieved with 5 kg of water and without PCM. The daily productivity is inversely proportional to the mass of water and the mass of PCM. The PCM reduces productivity by up to 11%. The results of daily simulations from April to October 2021 show that the daily productivity of the SS in Poland varies from 0.2 L/m2/day to 5.2 L/m2/day. The productivity of the SS investigated in this study in Poland is comparable to the productivity of solar stills investigated in countries with similar daily solar insolation and ambient air temperature.