Prolonged development of ore deposits, ore beneficiation and metallurgical smelting of concentrates result in the accumulation of wastes, forming large-scale dumps and sludge ponds negatively affecting the environment and human health. The creation and introduction of industrial waste treatment technologies will make it possible to dispose of them with the production of valuable commercial products and improve the environmental situation. In a research article on chemical beneficiation with the subsequent gravitational beneficiation of chrome-containing slurry tailings of Donskoy Ore-Mining and Beneficiation Plant (DOMBP), which processes chrome ore of the Kempirsay deposit in the Republic of Kazakhstan, Aktobe region, having considerable stocks of such waste is presented. The chromium-containing slurry tailings were heat-treated at 1100 °C, sintered with ammonium sulfate, water and sulfuric acid in a defined ratio at 300 °C, and then the resulting sinter was leached with water at 90 °... [more]

A sequencing batch reactor (SBR) inoculated with activated sludge and bioaugmented with a dye-decolorizing yeast strain—Yarrowia lipolytica (HOMOGST27AB) was assembled to form yeast-bioaugmented aerobic granular sludge (AGS). The bioaugmented AGS-SBR was operated for the treatment of synthetic saline wastewater (12 g L−1) intermittently fed with a reactive textile dye (Navy Everzol ED) at 25, 15, and 7.5 mg L−1. Dye degradation did not occur, although some dye adsorbed to the granules. AGS-SBR performance in removing carbon and nitrogen was good and was not affected by the dye addition. Bioaugmentation with the yeast Y. lipolytica (HOMOGST27AB) occurred with success, proved by sequencing samples from granules throughout the reactor operation. The AGS core microbiome gathered essentially microorganisms from the Proteobacteria and Bacteroidetes phyla. The microbial profile showed a dynamic microbiome established at Phase I of the operation, with a high decrease in the abundance of Ignavi... [more]

The production of titanium dioxide via the sulfuric acid process generates large amounts of acidic wastewater. Investigating the possibility of reusing this wastewater after deep treatment can reduce pollutant discharge and conserve water resources. In a pilot study, a dual-membrane method of ultrafiltration (UF) and reverse osmosis (RO) was employed to perform deep treatments of sulfuric-acid−titanium-dioxide wastewater. The findings showed that the multimedia and precision filters reduced the turbidity of water from an external drainage to as low as 0.18 NTU, with a turbidity removal rate of approximately 50%, reaching a maximum of 68%. When the UF effluent had a membrane flux of 70−100 L/m2 h and a water production rate of 85−90%, the SDI15 was <5.0 and the turbidity was 95%, a CODCr removal rate of 85%, and a desalination rate of >98.5%. At a smooth operation system water recovery rate of 50%, the highest system recovery rate obtained was 64%. The water produced via RO adhered t... [more]

A simple vapor-compression refrigeration system becomes ineffective and inefficient as it consumes a huge energy supply when operating between large temperature differences. Moreover, the recent Kigali amendment has raised a concern about phasing out some hydrofluorocarbon refrigerants due to their impact on the environment. In this paper, a numerical investigation is carried out to compare the performance of a cascade refrigeration system with two environmentally friendly refrigerant combinations, namely, R170−R404A and R41−R404A. Refrigerant R170, from the hydrocarbon category, and refrigerant R41, from the hydrofluorocarbon category, are separately chosen for the low-temperature circuit due to their similar thermophysical properties. On the other hand, refrigerant R404A is selected for the high-temperature circuit. An attempt is made to replace refrigerant R41 with refrigerant R170 as a possible alternative. The condenser temperature is kept constant at 40 °C, and the evaporator tem... [more]

Anaerobic ammonium oxidation (anammox, A) has become an appealing bioprocess for the water sector as a method to remove nitrogen (N) from wastewater using low-energy and organic carbon inputs [...]

Air source heat pump (ASHP) is a good new energy heating system. To explore the effect of ASHP on the production of yellow-feather broiler chicks, 31,500 one-day-old yellow broiler chicks were divided into three chicken houses with the same building structure but different heating methods (ASHP, CCF, CB). During the experiment, the parameters of heating time, temperature uniformity, gas concentration, weight gain, survival rate and production benefit were analyzed and evaluated. Results showed that the difference in NH3, CO2, and H2S concentrations was not significant in all test groups (p > 0.05). Only group II detected the CO gas. In winter and spring, the weight of the chickens in group II were weighed the least at 35 days of age, and were significantly different from the ASHP and CB system (p < 0.05). There was no significant difference in body weight between ASHP and CB (p > 0.05). Group II had the lowest evenness and survival, the slowest warming, the worst uniformity of temperat... [more]

This study investigated the use of ozone in a rotating packed bed (RPB) with liquid detention for the treatment of Basic Red 46 (BR-46). Liquid detention means that liquid accumulates at the lower section to a certain level in the RPB, which leads to longer liquid residence time and greater liquid holdup in the packing and cavity in the RPB. The experimental results showed that the presence of liquid detention in the RPB significantly enhanced the BR-46 treatment effect and ozone absorption rate. With 200 mL of liquid detention in the RPB, the decolorization rate, COD degradation rate, and ozone absorption rate were 34.7%, 62.8%, and 80.0% higher than those without liquid detention. The effects of the rotational speed of the RPB, ozone concentration, initial BR-46 concentration, liquid and gas flow rates on BR-46 degradation were also investigated, and it was found that the high-gravity environment is beneficial to the degradation of BR-46. These results suggest that with the utilizati... [more]

Energy production and consumption are dominant sources of CO2 emissions. Investigating the amount and characteristics of CO2 emission sources can aid in reducing CO2 emissions from energy-related sectors, which could lead to the development of advanced technologies and ideas for abatement. Cities play a significant role in CO2 emissions, representing a distinctive unit with a specialized energy consumption structure, meteorology, economy, agriculture, forest acreage, etc. Those properties interact and influence CO2 emissions. The city-level emission inventory is an important scientific database helping to investigate emission abatement technologies and establish control strategies. In this study, city-level CO2 emissions and ecological absorption of China’s coldest province are quantified. In the targeted region, winter lasts for about 6 months. Sectors of industry, thermal power generation, and domestic heating are dominant contributors to the total emissions. The provincial CO2 emiss... [more]

The increasing consumption of electrical and electronic equipment (EEE), correlated with the fast innovation pace in this field, generates a large amount of annual waste. The current established management practices cannot keep up with it, and the results are of increased significance given the negative effects on the environment and human health. Thus, the current study aimed to analyze the environmental impact of three different scenarios of waste electrical and electronic equipment (WEEE) management, following population awareness campaigns regarding its collection in the Municipality of Iasi, Romania. Data processing was carried out considering Life Cycle Assessment (LCA) methodology with the established functional unit for each scenario according to the collected amount. The results were quantified using the CML2001 and ReCiPe methods and showed that the highest environmental impact was obtained for scenario II (S2) (1.59 × 10−7 pers. equiv. using the CML2001 method and 32.7 pers.... [more]

Composting has been recognized as a sustainable technology to treat and manage organic waste [...]

This study was conducted in order to study the effect of different concentrations of lead pollution on the photosynthetic characteristics and growth of Miscanthus floridulus, and to reveal its photosynthetic adaptability to lead stress. The differences of gas exchange parameters, chlorophyll fluorescence characteristics and photosynthetic pigment of two Miscanthus floridulus populations, one population from Boluo an uncontaminated site, and another population from Dabaoshan, a mine site, were compared and studied through nutrient solution culture experiments treated with heavy metal lead (Pb) in green house. The results showed that (1) under Pb stress, the net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gs), intercellular carbon dioxide concentration (Ci), and chlorophyll content (Chl) of the leaves of the two populations decreased in different amplitude. Under moderate and severe Pb stress (80 mg·L−1, 120 mg·L−1, 240 mg·L−1), the plant biomass of non-minin... [more]

Ventilation Air Methane (VAM) refers to the release of fugitive methane (CH4) emissions into the atmosphere during underground coal mining operations. Growing concerns regarding the greenhouse effects of CH4 have led to a worldwide effort in developing efficient and cost-effective methods of capturing CH4. Among these, absorption-based processes, particularly those using Ionic Liquids (ILs) are appealing due to their advantages over conventional methods. In this study, the solubility of CH4 in various ILs, expressed by Henry’s law constant, is first reviewed by examining a wide range of experimental techniques. This is followed by a review of thermodynamic modelling tools such as the extended Henry’s law model, extended Pitzer’s model, Peng−Robinson (PR) equation of state, and Krichevsky−Kasarnovsky (KK) equation of state as well as computational (Artificial Neural Network) modelling approaches. The comprehensive analysis presented in this paper aims to provide a deeper understanding o... [more]

Iron-modified biochar adsorbent shows its promise for removing Cr(VI) from water. However, the traditional dry-grinding modification methods to prepare iron-modified biochar (DFeBC) usually result in the aggregation of iron oxide particles, thus impeding the adsorption capacity. Herein, blue-green algae waste derived biochar modified in a wet process by K2FeO4 (WFeBC) was developed, and it showed well-distributed iron oxide on the surface of the biochar. As a result, WFeBC displayed a larger theoretical adsorption capacity of 66.22 mg/g than that of DFeBC (48.54 mg/g). It was found that the uniform-distributed iron oxide and abundant oxygen functional groups of WFeBC played an important role in the removal process of Cr(VI). In the adsorption process, the reduction of Cr(VI) to Cr(III) by Fe(II) promoted the removal of hexavalent chromium. The Cr(VI) will be attracted by protonated oxygen functional groups through electrostatic interaction and complexation in an acid environment. All t... [more]

The production of palm oil, which is used in various foods, is associated with environmental destruction and climate change risks; therefore, there is an urgent need for sustainable alternatives. “Yeast oil” produced by Lipomyces starkeyi, an oil-producing yeast, is expected to solve these problems because its fatty acid composition is similar to that of palm oil. To date, we have successfully developed yeast oil as an edible alternative to palm oil. However, conventional processes, including cell collection and lyophilization, are difficult to industrialize in terms of equipment and cost. Therefore, a method for extracting yeast oil from the emulsified liquid generated by crushing the culture was investigated. It is presumed that the emulsified state is stable owing to the components derived from yeast cells and metabolites; thus, solid−liquid filtration separation was attempted before extraction. The extraction recovery ratio of yeast oil was 98.2% when a hexane/ethanol mixture (3:1)... [more]

Achieving plastic circularity is imperative to using plastics without adverse effects. Today, only 9% of global plastic waste is recycled, signifying the need for more substantial advancements to accelerate our progress toward achieving plastic circularity. This article contributes to our collective efforts to accelerate plastic circularity by critically assessing the state-of-the-art, gaps, and outlook of the pathways and processes to circular plastics. It employs qualitative methods to derive new insights that empower scholars and practitioners to prescribe effective strategies to shape the future of plastic circularity and its research agenda. This article concludes that today’s circularity pathways for plastics are not economically viable, significantly hindering their scalability and widespread adoption. It further validates that focusing on the product design and effectiveness of the available collection and sorting systems can considerably improve our progress in achieving plast... [more]

The adsorption of polymer microspheres in a stratum can directly affect its action mode and performance in the actual application process. Understanding the adsorption pattern of polymer microspheres and their adsorption mechanism can facilitate optimization of the application mode and enhance the use efficiency. Ultraviolet spectrophotometry was employed to measure the static adsorption characteristics of polymer microspheres (PMS) on the surface of quartz sand. The PMS adsorption capacity on the surface of quartz sand increased with increasing concentration. When the concentration was 1000 mg/L, the static equilibrium adsorption capacity was 402 μg/g, and monolayer adsorption was dominant. The effect of the contact time on the adsorption was investigated, and the fitting was performed using the isothermal adsorption thermodynamic equilibrium model and the adsorption kinetic model. The adsorption of 800 mg/L PMS tended to equilibrate after 0.8 h of adsorption on the surface of quartz... [more]

Saffron spices are composed of dehydrated stigmas of Crocus sativus L. A large amount of bio-residues (stamens, tepals, and stigmas) is generated during the production of this spice (~92 g of bio-residues per 100 g of flowers). These bio-residues are usually discarded losing the chance to obtain interesting bioactive compounds from them. In this work, we use the saffron bio-residues as possible source of natural bioactive compounds. Different extraction conditions were applied obtaining hydrophilic and lipophilic components. The antioxidant activity of the bioactive compounds in the different conditions were analysed using the ABTS method developed by our team. Furthermore, the total content of phenolic compounds and flavonoids present in the bio-residues were estimated. We demonstrated that bio-residues contain a high amount of both phenolic and flavonoid compounds with a strong antioxidant potential effect. Moreover, we compared the antioxidant activities of saffron bio-residues (obt... [more]

Environmental protection laws require effective and green solutions to tackle water and air pollution issues. For this purpose, perovskite photocatalytic materials have proven to be a promising solution. In this study, CsSnBr3 perovskite, coupled with ZIF-67 and decorated with noble metal Au, was shown to effectively enhance the charge separation and increase the light-absorbing capacity, and thus make the photocatalytic reaction more efficient by surface plasmon resonance. Characterization results from XRD, FTIR, and UV-visible diffuse reflectance spectroscopy indicated that a mixture of cubic and tetragonal crystalline phases was found in the prepared catalyst material. XPS also revealed that in the presence of two oxidation states for tin (Sn), the Au 4f XPS peaks of Au NPs coincided with those retained in colloidal Au particles. Using malachite green as a model compound, organic pollutant photocatalytic degradation tests proved that CsSnBr3 generated good photocatalytic activity fo... [more]

Japanese knotweed is an invasive alien plant species with characteristic rapid expansion in Europe and North America and resistance to extermination. It displaces autochthonous biodiversity and causes major damage to infrastructure, thus causing global ecological and economic damage. The Japanese knotweed plant is usually eradicated using various chemical, biological, or mechanical techniques, which at a large scale include heavy equipment, usually followed by incineration. Therefore, excavation is preferred to eradication techniques, and as a biomass waste recovery method due to the extraction of high-value biocompounds. This is supported by the fact that the Japanese knotweed possesses various bioactive compounds with beneficial effects on human health. Its rhizome bark extract produces strong and stable antioxidant activity over time, as well as apoptotic, antibacterial, and other beneficial activities. In this work, an environmental impact assessment, including greenhouse gas footp... [more]

Cobalt oxide has good catalytic activity for peroxydisulfate (PDS) activation but poor stability and is vulnerable to inactivation because of agglomeration. In this work, the chlortetracycline (CTC) degradation by peroxydisulfate (PDS) catalysis using the reduced graphene oxide support cobalt oxide (Co3O4/rGO) composite catalyst was investigated. It was found that 86.3% of CTC was degraded within 120 min in the Co3O4/rGO-800/PDS system. The influences of catalyst dosage, PDS concentration, solution pH, and reaction temperature were systematically explored. The excellent removal performance of CTC could be attributed to the synergistic effect between adsorption and catalytic degradation. ≡Co2+ and surface functional groups played as active sites to catalyze PDS, and the circulation of ≡Co2+/≡Co3+ was achieved. Moreover, Co3O4/rGO-800 showed satisfactory reusability after three cycles. This research can provide useful information for the development of efficient PDS catalysts and facilit... [more]

The environment consists of living and inanimate elements that mutually interact and affect each other’s health and lifespan [...]

Researchers, architects and planners are increasingly urged to develop and apply sustainable methods and solutions to reduce the impact of the built environment on climate, adapt cities to climate change and reduce or eliminate resource depletion and building-related carbon emissions. In recent years, taking advantage of state-of-the-art computational and environmental design tools, researchers and designers are developing new digital workflows, methods and solutions to investigate climate-optimal and performative buildings and urban forms. This perspective paper analyses state-of-the-art computational methods; form generation processes; and tools, criteria and workflows that present how these are integrated into climatic form finding, allowing the improvement of building and urban environmental performances. Additionally, current challenges and future directions are presented.

This work demonstrates that the quasi-homogeneous distribution of concentrated solar flux is achievable by using double paraboloid reflection, with a primary reflector to concentrate the sunlight, and a secondary reflector to homogenise the radiation flux. For that, three slightly different secondary reflectors were designed and manufactured, matching the specifications of the paraboloid concentrator of the SF60 solar furnace located in PSA—Plataforma Solar de Almería, which was used as primary reflector. Starting from preliminary simulations of the optical apparatus, the secondary geometries were selected and then the reflectors were manufactured from 7075-T6 aluminium alloy, using conventional and CNC machining technologies, with further processing to achieve a mirror-like finish. The results obtained from solar irradiation tests corroborate that the “double paraboloid reflection” methodology proposed in previous theoretical works seems to be technically feasible and can be a solutio... [more]

The Association of the Southeast Asian Nations (ASEAN) region is a critical contributor to global development from an environmental perspective. This study has reviewed carbon emissions from energy generation, influence factors from the population, economic growth and renewable energy, emission and energy intensity projection, spatial distribution characteristics, and decarbonization strategy. This work utilizes a comparison methodology between ASEAN countries in the emission intensity and energy intensity in the future projection of electricity conditions in 2030 or 2040, as well as opportunities for reducing greenhouse gas (GHG) emissions as determined by the national policies of each government. The results show that Indonesia, Vietnam, Thailand, and Malaysia produce 79.7% of the electricity in the ASEAN region. As a developing country, Indonesia has the largest population and gross domestic product (GDP) but has the highest predicted emission intensity, of 0.97 CO2e/MWh, in 2030. V... [more]

Understanding the micro-occurrence mechanism of tight oil has long been a daunting challenge in the exploration and development of unconventional resources. This article discusses the micro-occurrence mechanism of tight oil through continuous extraction by combining thin casting, fluorescent thin sections, environmental scanning electron microscope observations, physical property testing, and X-ray diffraction experiments. The results indicated that in the tight sandstone of the Chang 8 Formation in the Ordos Basin, the average tight oil content was 35.46% for microscale pores, 35.74% for nanoscale pores, and 28.79% for mineral surfaces. Six types of micro-occurrence states of tight oil were identified: emulsion, cluster, throat, star-like, isolation, and thin film forms. Although clay minerals and heavy components dominate the adsorption of tight oil on mineral surfaces, micro-occurrence is fundamentally an oil−rock interaction process. Hence, oil−rock interactions and occurrence stat... [more]