A circular economy (CE) promotes the reuse, reincorporation and valuation of waste and by-products under the framework of sustainable development through models and indicators that evaluate scenarios of second use and reduction in non-incorporated outputs to reduce negative externalities and pressures on the dimensions of development. A CE model applied to the transformation process of RFF in agro-industries is developed, which consists in the identification of the residue coefficients of EFB (22.48% ± 0.8), fiber (15.58% ± 0.49), husk (6.03% ± 0.66) and ash (0.55% ± 1.67). Subsequently, the valuation trends of potential second use were verified through a systematic review, which allowed the construction of the scenario of avoided costs of USD 678,721.5, a product of the total use of the outputs under bioenergy and nutrient source approaches. Finally, the RRSFM indicator was constructed, which can reach the level of 72% and a degree of improvement of 26% by 2026. In parallel, the HCRRS... [more]

Slaughterhouse wastewater (SHWW) is classified as industrial waste, which is exceptionally harmful to the environment due to its high content of biological oxygen demand (BOD), chemical oxygen demand (COD), and suspended solids, which result from high organic and nutrient loading. This study used a pilot system to treat SHWW from the Kafrelsheikh Governorate slaughterhouse, which includes a three-step process. It started with sedimentation, then coagulation and flocculation using different concentrations of each: natural zeolites (Z) and Psidium guajava-leaf powder (GLP) as green and environmentally friendly agents, and alum (A) as an inorganic coagulant. The final step was filtration with physically treated rice straw (RS). Each step was judged separately by measuring the removal percentages of each analyzed pollutant, and finally, the overall process was evaluated using the same method. A jar test was used to determine the best concentration of each coagulant used. The measured pollu... [more]

In the context of climate change and the reduction in CO2 emissions from fossil fuel combustion, the integration of CO2 capture technologies in steam power plants is a key solution. The aim of this study was to analyze the use of ammonia, at different mass concentrations, in capturing post-combustion CO2 in a coal-fired power station and comparing it with the reference 30% MEA case. In this regard, a multi-criteria model was developed to establish the optimal solvent used, considering the least impact on technical performance, economic, and environmental indicators. As a result, the lowest CO2 capture cost was obtained for the CO2 capture process based on 7% NH3, with 59.07 €/tCO2. Integration of the CO2 capture process is more economically viable when the CO2 emissions tax is higher than 70 €/tCO2 for 7% NH3 and 15% NH3, 80 €/tCO2 for 5% NH3 and 30% MEA, and 90 €/tCO2 for 2% NH3. Regarding the overall efficiency, the energy penalty associated with the CO2 capture process integration v... [more]

The high intensity of solar radiation and long sunshine time in the Turpan area lead to the necessity of sunshade construction. Sunshade components can effectively block direct solar radiation and the secondary heating of buildings. Through the analysis of the importance and sensitivity of sunshade components, it was found that the importance of sunshade components accounts for the largest proportion of multi-parameters, and the sensitivity of sunshade components accounts for about 60% of the total. At the same time, the change in sunshade length has an important influence on the proportion of air conditioning energy consumption and space comfort when the sunshade length reached the 0.6 m−0.8 m range. The energy consumption curve of air conditioning no longer decreased and tended to be horizontal, which showed that a sunshade could effectively reduce the energy consumption of air conditioning, while the PMV comfort curve gradually increased and tended to be horizontal, indicating that... [more]

Efficient and reasonable utilization of waste biomass resources can not only avoid serious waste of material resources, but also solve the problem of environmental pollution. Therefore, the development of efficient and environmentally friendly waste biomass carbonization technology has important practical significance. Here, the activated carbon from orange peel (OAC) is prepared by potassium hydroxide (KOH) activation combined with high-temperature carbonization. The adsorption effects of OAC on three different pollutant aqueous solutions, methylene blue (MB), tetracycline (TC), and fluorescein sodium (NaFL), are examined. The OAC absorbent has excellent adsorption capacity for MB, TC, and NaFL pollutants of 10 mg L−1, with adsorption rates of 99.17%, 73.5%, and 94.24%, respectively. This study provides a new idea for turning waste biomass into treasure and eliminating the hidden danger of environmental pollution.

China’s LNG import volume in 2021 reached 121.356 million tons, which makes China the largest importer in the world. The ambient air vaporizer (AAV) for LNG vaporization is an ideal selection for minimizing the average monetary value of terminals and maximizing operating efficiency. However, the heat and mass transfer performance of real multi-component LNG is not the same as that of the pure component in AAV; what is more, deep cryogenic and multi-component characteristics of LNG could lead to the deterioration of heat-transfer performance, which may cause catastrophic consequences. Thus, this difficulty should be concerning and solved in its operation. Based on the law of conservation of energy and mass, a heat and mass transfer model was established that can calculate the coupled heat transfer from the LNG to the air-side of the AAV along its own length. Empirical correlations are proposed to predict some basic properties of the frost layer at the outside of the tube, where the inte... [more]

A thin-film solid-phase microextraction method with a sorbent composed of a deep eutectic solvent was developed for the preconcentration of formaldehyde from river and lake water samples. Four new deep eutectic solvents (DESs) were synthesized, each in molar ratios 1:1, 1:2, and 1:3. Among prepared compounds, the greatest efficiency in the proposed method of preconcentration of formaldehyde derivatized with Nash reagent was demonstrated by DES-3 consisting of benzyldimethylhexadecylammonium chloride and lauric acid, in a molar ratio of 1:3. For the proposed method, the parameters affecting the extraction efficiency of formaldehyde were optimized (including the choice of DES-based sorbent and desorption solvent as well as the sample volume and pH, the salting-out effect, the extraction time, and the desorption time). Under optimal conditions, the proposed method achieved good precision between 3.3% (for single sorbent) and 4.8% (for sorbent-to-sorbent) as well as good recovery ranging f... [more]

Petroleum is the most common global fossil fuel. It is a complex multi-component system mainly composed of various hydrocarbons such as alkanes, cycloalkanes, mono-, bi- and polyaromatic compounds, resins and asphaltenes. In spite of humanity’s need for petroleum, it negatively affects the environment due to its toxicity. The ecological problem is especially serious at petroleum mining sites or during petroleum transportation. Since it is not possible to replace petroleum with less toxic fuel, ways to reduce the toxic impact of petroleum hydrocarbons on the environment need to be developed. This review addresses bioremediation, a biological approach to petroleum degradation, which is mainly performed by microbes. The pathways of degradation of alkanes, alkenes and aromatic hydrocarbons are presented in detail. The effects of temperature, aeration and the presence of biogenic elements on microbial degradation of petroleum are discussed. Plant−microbe interactions involved with the biore... [more]

Based on the nonlinear piezomagnetic equation, the piezomagnetic effect of prismatic iron-cobalt alloy is analyzed by using the ANSYS finite element simulation platform. The variation of the dynamic piezomagnetic coefficient of the iron-cobalt alloy under different bias magnetic fields and different stress was studied through simulation. Referring to the working condition of the tractor force sensor and according to the principle of magnetic circuit superposition, a piezomagnetic force sensor was designed and manufactured using iron-cobalt alloy. According to the electromagnetic theory and piezomagnetic effect, the three-dimensional model and magnetic circuit mathematical model of the sensor are established, and the system simulation model of the piezomagnetic sensor was established based on the MATLAB/Simulink module. The experimental platform of the magnetostrictive force sensor was built to verify the correctness of the simulation model, and the effects of bias magnetic field and fo... [more]

In this article, the Dimethyl Carbonate (DMC) synthesis process was investigated thermodynamically based on a well-optimized DMC system for a developed configuration, according to a real industrial plant, presented by Huang et al. Exergy analysis was performed using ProSimPlus software as an efficient process modeling and simulation environment that is uniquely capable of exergy balance computations. The key operational variables such as the reflux ratio (Rr), feed temperatures, and feed tray location were varied to explore their impact on the total irreversibilities, global intrinsic efficiency, and DMC purity. The influence of the high pressure (HP) column reflux ratio was the most effective parameter on the exergy destruction and DMC purity, which also significantly increased the duties of the HP column reboiler and condenser. The steady state results are reported in comparison with those found in the literature, and an excellent match is shown between them.

This work proposes a suitable treatment for the leachates from a sewage sludge composting process using a specific windrow (biopile). The biopile’s evolution and organic content degradation were followed for 2 months with regular leachate spraying to assess the physico-chemical and biological impacts, and determine the risk of enrichment with certain monitored pollutants. The final objective was the valorization of the biopile substrates in the composting process, while respecting the quality standards of use in a circular economy way. Classical physico-chemical parameters (pH, conductivity, dissolved organic carbon (DOC), total dissolved nitrogen (TDN), etc.) were measured in the leachates and in the water-extractable and dry-solid fractions of the biopile, and the catabolic evolution of the micro-organisms (diversity and activities), as well as the enrichment with persistent organic pollutants (POPs) (prioritized PAHs (polycyclic aromatic hydrocarbons) and PCBs (polychlorinated biphe... [more]

Urban water systems are still in their infancy regarding the transition toward a circular economy, despite the sporadic successful examples worldwide. This paper was aimed at analyzing the preparedness of four water utilities in Bulgaria for the implementation of circular economy principles and solutions. These utilities provide water supply and sewerage services to about 30% of the population in Bulgaria. SWOT analysis was used as a core tool. Publicly available data such as nonrevenue water, pressure management, energy demand, network digitalization, and sludge utilization were used to explore the internal factors. The external environment was considered through the legislative and socioeconomic framework, climate change, etc. Finally, the credibility of the conclusions was verified in workshops with the water utilities. The key positive outcomes were that the external factors favor the shift to circular systems, while the major weakness, i.e., the aged infrastructure, is actually a... [more]

Even though Industry 4.0 is primarily focused on the implementation of advanced digital technologies, this is not the only aspect that should be considered. One of the aspects that calls for attention is the ability to create a sustainable and agile industrial environment. In this sense, the role of project management is crucial for achieving business excellence in a new industrial paradigm. The main goal of this paper was to determine the impact of different levels of project management maturity on business excellence in the context of Industry 4.0. The research in the paper was made using a sample of 124 organizations, differing in industry type and size, and recognized through the business excellence awards or recognitions given by European Foundation for Quality Management (EFQM). Using the Project Management Maturity Model (ProMMM), a significant connection was found between project management maturity and business excellence. Considering technology advances, these relationships w... [more]

The research of the fundamentals of the behavior of behavior in the soil−plant system during their co-contamination is of high interest because of the absence of technologies for the creation of effective, environmentally friendly and cost-effective remediation methods, as well as integrated systems for predicting the quality of soils co-contaminated with HMs and PAHs. The unique model vegetation experiment was studied with Haplic Chernozem contaminated by one of the priority organic toxicants, benzo[a]pyrene (BaP), applied alone and co-contaminated with Cu with the subsequent vegetation of tomato (Solanum lycopersicum) and spring barley plants (Hordeum sativum Distichum). Biochar obtained from sunflower husks was used as a sorbent for the remediation of the contaminated soil. It was established that by increasing the BaP amount applied to the soil, the rate of BaP degradation improved. The effect was enhanced in the presence of biochar and decreased in the case of joint co-contaminati... [more]

Arsenic (As), cadmium (Cd), and copper (Cu) are the primary inorganic pollutants commonly found in contaminated soils. The simultaneous stabilization of the three elements is a preferred approach for mixture-contaminated soils which has received extensive research attention. However, few studies have focused on the immobilization efficiency of a single amendment on the three elements. In this study, phosphate, red mud, and biochar were used to remediate As (237.8 mg kg−1), Cd (28.72 mg kg−1), and Cu (366.5 mg kg−1) co-contaminated soil using a 180-day incubation study. The BCR (European Community Bureau of Reference) extraction method, NH4H2PO4−extractable As, and diethylenetriamine penta-acetic acid (DTPA)−extractable Cd and Cu were analyzed at different time intervals. The results indicated that the application of red mud and biochar significantly reduced soil DTPA−Cd and Cu concentrations during the incubation, while the decrease in soil NH4H2PO4−As was much less than that of soil D... [more]

Natural gas hydrate (NGH) is a kind of unique resource among hydrocarbon fuels. It is stable within its sedimentary hosts and will only convert to its constituent gas and water phases relatively quickly if reservoir pressure-temperature conditions are artificially disturbed. The unwanted vibrations from the drill string with the complex external environment and excitation usually cause instability in the NGH. In this paper, a nonlinear mathematical model is presented taking into account the fluid−solid coupling vibration caused by the drilling fluid inside and outside the drill string, the non-smooth rub-impact between the drill string and borehole wall, and the influence of centralizer setting interval on nonlinear resonant vibration of the drill string. The relationship between the variable parameters of the drill string and the complex dynamics of the drill string is analyzed. Finally, the bifurcation diagram is given. The results show that the system response exhibits complex dynam... [more]

The competitiveness of companies in emerging countries implies many European countries must transform their production systems to be more efficient. Indeed, the new context created by the COVID-19 pandemic increases the necessity of digital transformation and focuses attention on its limited uptake by manufacturing companies. In France, the Industry 4.0 concepts are already implemented in large companies. Despite the demonstration and validation of their benefits, SMEs are reluctant to move towards implementation. This problem of SME performance improvement increases with the current geopolitical situation in Europe (raw materials and gasoil cost). It is thus urgent and paramount to find a better solution for encouraging SMEs in their transformation. Taking note of the brakes on uptake of Industry 4.0 concepts in SMEs, the objectives of this paper are to find levers to accelerate implementation of Industry 4.0 concepts in SMEs, through the development and the deployment of a sustainabl... [more]

Based on the empirical literature of the payments for environmental services (PES) projects for the environmental improvement and poverty reduction, this paper uses a meta-regression analysis method to study whether PES can achieve the effects of improving environmental quality and reducing poverty levels. For the meta-regression analysis, the literature was mainly searched by the Web of Science core journal database. The explanatory variables of meta-regression analysis are the hypothesis and related features of the models in the original literature by generally taking the binary dummy variables or categorical variables. The dependent variables used in this paper are environmental improvement and poverty reduction. The results show that PES projects based on private ownership rights are more conducive to poverty reduction and environmental improvement. If the country is a buyer of a PES project, it is more likely to achieve the effects of environmental enhancement and poverty alleviat... [more]

Extending the use of a component without compromising its intended functionality is the neatest approach to enhance sustainability. From this perspective, limiting the working life of a cutting tool based merely on the blunting of its cutting edge to a specific value is highly questionable. The very question that serves as the motivation for this work is, “why should tool life criterion be based on the shape of the tool when all that matters for business is the quality of the part being machined?”. This work puts forward a tool life criterion based on the surface quality of the machined part. The proof of the concept is provided by a series of face-turning experiments performed on a commonly used alloy steel using the following cutting inserts in dry conditions: (1) uncoated carbide; (2) coated carbide; and (3) cubic boron nitride (CBN). It is found that different combinations of tooling and cutting parameters lead to entirely different values of surface roughness at the same level of... [more]

Borehole instability problems are commonly encountered while drilling highly deviated and horizontal shale gas wells within the shale formations associated with high-dip bedding planes. An integrated rock mechanical study is described in this paper to evaluate the risk of the borehole instability problems in this area. First, a set of uniaxial compressive tests are carried out to measure the strength of the bedding shales on cores with different angles between the load direction and the bedding planes. A critical strength criterion is then proposed based on the test results. Next, the stress state of the borehole with arbitrary inclination and azimuth is determined through coordinate transformations. Finally, through combining the strength criterion and the stress state of the borehole, the risk of borehole instability is investigated for deviated and horizontal wells in shale formations with different bedding dips (0−90°) and dip directions (45° and 90° to the direction of minimum hor... [more]

Protective coal seam mining can not only effectively prevent coal and gas outbursts in mines, but also provide stress unloading space for the protected coal seam. The coal body in the protected coal seam might undergo deformation, internal damage and structural damage, which changes its gas seepage characteristics. This study aims to explore the variations of permeability of the coal body in the protected coal seam under axial unloading. With the coal body from the outburst coal seam in the Huaibei mining area as the research object, experiments were conducted to explore the gas seepage characteristics of axially unloaded coal body under different confining pressures and gas pressures, using the TAWD-2000 coal-rock mechanics-seepage experimental system. According to the results, with respect to the gas seepage, the variations of permeabilities of axially unloaded coal samples are closely related to their deformation and damage. As the confining pressure and gas pressure rise, the diffe... [more]

This work aims to characterize the adsorption process of propranolol HCl, an emerging pollutant and a widely used β-blocker, onto kiwi peels, an agricultural waste. The use of UV-vis spectroscopy was considered to obtain information about the pollutant removal working in the in-batch mode. In a relatively short time, the adsorption process could remove the pollutant from water. A kiwi peel maximum adsorption capacity of 2 mg/g was obtained. With the perspective of scaling up the process, preliminary in-flux measurements were also performed. The investigation of the whole in-batch adsorption process was conducted by studying the effect of ionic strength (adopting salt concentrations from 0 to 0.4 M), pH values (from 2 to 12), adsorbent/pollutant amounts (from 25 to 100 mg and from 7.5 to 15 mg/L, respectively), and temperature values (from 289 to 305 K). The thermodynamics, the adsorption isotherms, and the kinetics of the adsorption process were also carefully investigated. The Langmui... [more]

Carbon Capture, Utilization and Storage (CCUS) is a method of burying the captured CO2 into the reservoir and displacement of crude oil from reservoirs, which considers both economy and environmental protection. At present, it is considered as an important means to deal with global climate change. To ensure the safety of the CCUS scheme, it is very important to study the invasion and migration of CO2 in different types of caprocks. In this paper, we first choose the injection-production method of fixed gas injection rate at the top of the reservoir and constant pressure oil production at the bottom. Secondly, the distribution of porosity and permeability in the caprock is designed, and four types of caprock models are established: homogeneous caprock, layered homogeneous caprock, heterogeneous caprock, and layered heterogeneous caprock. Finally, the intrusion amount and migration characteristics of CO2 in caprock of four schemes in injection-production stage and burial stage are studie... [more]

Heating, ventilation, air conditioning and refrigeration (HVAC&R) systems provide physical environment comfort for the occupants at a possible expense of large amount of energy consumption [...]

Air pollution is a problem shared by the entire world population, and researchers have highlighted its adverse effects on human health in recent years. The object of this paper was the relationship between the pollutants’ concentrations measured in the air and the quantity of pollutant itself inhaled by the human body. The area chosen for the study has a high environmental impact given the significant presence on the territory of polluting activities. The Acerra area (HI) has a waste-to-energy plant and numerous industries to which polluting emissions are attributed. This area has always been the subject of study as the numbers of cancer patients are high. A survey on male patients to evaluate the heavy metals concentrations in the blood was conducted in the two areas and then linked to its values aero-dispersed. Using the air quality data measured by the monitoring networks in two zones, one with high environmental impact (HI) and one with low environmental impact (LI), the chronicle... [more]