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The safe application of farm dairy effluent (FDE) to land has proven to be a challenge for dairy farmers and regulatory authorities throughout New Zealand. Poorly performing FDE systems can have deleterious effects on water quality because contaminants such as phosphorus, nitrogen and faecal microbes enter receiving waters with minimal attenuation by soil. We present a decision framework that supports good management of effluent, particularly during its application to land. The framework considers how FDE management can be tailored to account for soil and landscape features of a location that pose varying levels of contaminant transport risk. High risk soils and landscapes are vulnerable to direct losses via preferential and/or overland flow pathways and include sloping land (e.g. slopes greater than 7 degrees) and soils with mole drainage, coarse structure, poor natural drainage or low surface infiltration rates. Soil types that are well-drained with fine structure typically exhibit matrix flow characteristics and represent a relatively low risk of direct contaminant loss following FDE application. Our framework provides guidance on FDE application timings, rates and depths to different landform and soil types so that direct losses of contaminants to water are minimal and the opportunity for plant uptake of nutrients is enabled. Some potential limitations for using the framework include the potentially severe effects of animal treading damage during wet conditions that can reduce soil hydrological function and consequently increase the risk of overland flow of applied FDE. The spatial distribution of such treading damage should be considered in the framework's application. Another limitation is our limited understanding of the effects of soil hydrophobicity on FDE infiltration and application of the framework.

期刊论文 2025-06-11 DOI: 10.1080/00288233.2025.2500582 ISSN: 0028-8233

The study explored the long-term efficiency of an integrated electrodialysis-forward osmosis (EDFO) treatment technology for nutrient recovery and its application in irrigating and fertilizing high-value crops. Results showed a stable energy profile with consistent electrical conductivity (EC) trends in both municipal and dairy digestates, highlighting the system's capacity to maintain ionic stability, essential for long-term operation. Fouling resistance was indicated by gradual and minimal declines in current density, reflecting stable performance after three cycles and reducing the need for chemical cleaning. A greenhouse trial assessed the impact of using treated and untreated wastewater for irrigation on plant growth and nutrient dynamics in southern highbush blueberry (Vaccinium corymbosum L. interspecific hybrid). The plants were grown in a soilless potting media and irrigated with a modified Hoagland nutrient solution (control), untreated municipal or dairy digestate, or recovered nutrient water from municipal or dairy digestate treated by the EDFO process. Leaf area and shoot biomass were similar among the treatments, confirming that wastewater irrigation did not adversely affect blueberry growth. Furthermore, pH levels in the potting media were near or within the optimal range for blueberry cultivation (4.5-5.5), while EC exceeded salinity thresholds for the crop (> 2 dS m(-1)) but did not visibly damage the plants, suggesting that salt levels were manageable with periodic freshwater flushing. Mass-spectrometry-based, non-targeted analysis detected significant reductions in organic pollutants across treatment cycles. In particular, pharmaceuticals and pesticides in untreated digestate were reduced by over 90 % post-treatment, affirming the system's efficacy in removing emerging contaminants that could pose risks in agriculture and consumers. Given the favorable nutrient recovery and contaminant removal, the EDFO system offers a sustainable solution for wastewater reuse, enabling nutrient cycling in agricultural systems and reducing freshwater dependence.

期刊论文 2025-06-01 DOI: 10.1016/j.jece.2025.117178 ISSN: 2213-2929

The environment has been damaged due to anthropogenic activities related to the production and consumption of cattle. The present study investigated the pollution potentials of slaughterhouse effluents on groundwater qualities in Ebonyi State Southeast Nigeria, with the specific objectives to determine the effect of slaughterhouse effluents on both microbiological, physicochemical and heavy metal parameters on the quality of groundwater. Eighty-four well water samples were taken in 2022 and 2023 from slaughterhouse locations, and a control location for the determination of physicochemical properties and microbiological contents using standard analytical methods. Datasets were analyzed using Fisher's Significance Least Difference (F-LSD) at 0.05 probability level. The study recorded higher levels of physicochemical, BOD, COD, Salinity, bacterial and fungal counts in the slaughterhouses well waters when compared to the control well water. With the exception of chloride, ammonia, copper and electrical conductivity, all water parameters were significant in both years. The result of the study also demonstrated that, with the exception of ammonia, lead, biological oxygen demand, chemical oxygen demand, salinity, salmonella spp, shigella spp, E. coli, and other coliforms, the majority of the analysed parameters were within the World Health Organisation recommended standard. In addition, as compared to the first year of study, the well water parameters were generally higher in the second year. In order to prevent groundwater pollution, the present study suggests that slaughterhouse effluents be disposed of in an environmentally responsible manner through the segregation of waste materials to prevent groundwater pollution.

期刊论文 2025-05-04 DOI: 10.1080/15275922.2024.2431322 ISSN: 1527-5922

Large quantities of hazardous heavy metals found in industrial wastes and are adequate to make crops toxic and these noxious metals accumulate in plant tissues can cause deleterious effects in plants. The current investigation was carried out to assess the physiological response of onion plants in textile effluents contaminated soil and to determine the role of silicone in the onion plant under oxidative stress. The industrial effluent was used at the rate of control, 30 %, 60 % and 100 % effluents. Following treatment applications were made (30 % +Si, 60 % +Si, 100 % effluents + Si,0 % +Si). Various physiological and enzymatic parameters were studied. The complete randomized design (CRD) with triplicates was used for the experiment. Treatment T4 (seed + 100 % effluents) was most toxic and 43 % shoot length, 51 % root length, 47 % membrane damage,74 % chlorophyll a,67 % chl b, 82 %carotenoids, and 44 %, catalase inhibition was observed over (T1). Similarly, MDA content and membrane damage were also higher in T4 (237,189 %) as control. The (seed+ Si) was found most effective in terms of onion growth which increased the shoot length, root length, chl a, chl b, carotenoids, and SOD (34, 51,70,284, 175, and 174 %) higher as compared to T1 respectively. It is concluded from the current investigation that textile effluents contain various toxic materials, especially heavy metals which can adversely affect the onion plant and silicon suppressed the toxicity of effluents in plant, Si can be used l to overcome toxic effect of industrial waste and plant growth promotion

期刊论文 2025-03-15 DOI: 10.1016/j.scienta.2025.114082 ISSN: 0304-4238

Domestic laundry wastewater is a major contributor to microfiber emissions in the aquatic environment. Among several mitigation measures, the use of external filters to capture microfibers from wastewater is one of the most efficient and commercially viable methods. This study attempted to develop an eco-friendly filtration medium to filter microfibers in laundry wastewater using luffa cylindrica fibers. Sourced luffa fibers were made into tight rolls and stacked in a filtration column to filter the effluent. The analysis showed that the alkali-treated luffa fiber rolls were more effective in filtering the microfibers than untreated luffa fibers. Hence, the alkali treatment process was optimized for better performance; an alkali concentration of 5.8%, treatment time of 5 h, and 37 degrees C temperature provide better performance. The characterization of alkali-treated luffa fibers showed significant changes in the morphology and removal of lignin and hemicellulose components, enhancing the physical adsorption of microfibers on the surface. The experimental filtration results showed that the developed filter can effectively remove up to 93% of microfibers from laundry effluent, and the efficiency remained superior for up to 15 filtrations. Furthermore, an increase in filtration leads to the accumulation of detergents in the luffa net-like vascular structure and reduced effectiveness. The use of the developed product in a real-time washing machine outlet was found to be effective with an efficiency of 98%. The developed product is a versatile and cost-effective solution, suitable for use in domestic washing machines. Its simplicity and ease of integration make it an effective and eco-friendly alternative for filtering microfibers from laundry effluent. The future direction of the study also suggests a sustainable disposal method for luffa fibers using it as a matrix material in red soil-based thermal or sound insulation panels and restricting the reach of microfibers into the environment.

期刊论文 2025-02-01 DOI: 10.1016/j.jenvman.2025.124251 ISSN: 0301-4797

In the waterway construction projects of the upper reaches of the Yangtze River, crushed mudstone particles are widely used to backfill the foundations of rock-socketed concrete-filled steel tube (RSCFST) piles, a structure widely adopted in port constructions. In these projects, the steel-mudstone interfaces experience complex loading conditions, and the surface profile tends to vary within certain ranges during construction and operation. The changes in boundary conditions and material profile significantly impact the bearing performance of these piles when subjected to cyclic loads, such as ship impacts, water level fluctuations, and wave-induced loads. Therefore, it is necessary to investigate the shear characteristics of the RSCFST pile-soil interface under cyclic vertical loading, particularly in relation to varying deformation levels in the steel casing's outer profile. In this study, a series of cyclic direct shear tests are carried out to investigate the influential mechanisms of roughness on the cyclic behavior of RSCFST pile-soil interfaces. The impacts of roughness on shear stress, shear stiffness, damping ratio, normal stress, and particle breakage ratio are discussed separately and can be summarized as follows: (1) During the initial phase of cyclic shearing, increased roughness correlates with higher interfacial shear strength and anisotropy, but also exacerbates interfacial particle breakage. Consequently, the sample undergoes more significant shear contraction, leading to reduced interfacial shear strength and anisotropy in the later stages. (2) The damping ratio of the rough interface exhibits an initial increase followed by a decrease, while the smooth interface demonstrates the exact opposite trend. The variation in damping ratio characteristics corresponds to the transition from soil-structure to soil-soil interfacial shearing. (3) Shear contraction is more pronounced in rough interface samples compared to the smooth interface, indicating that particle breakage has a greater impact on soil shear contraction compared to densification.

期刊论文 2025-01-01 DOI: 10.3390/buildings15010141

Aerosols are liquid and solid particles suspended in the atmosphere and have a broad size range; they can cool the Earth by scattering radiation back to space or warm the Earth by absorbing radiation directly. Since the industrial revolution, the loading of aerosols in the Earth's atmosphere has increased significantly, yielding modifications to the Earth's energy budget and further affecting the climate state. Aerosol direct radiative forcing (ADRF), defined as the difference in radiation with and without total or specific aerosols, is an important concept used to describe the direct impact of aerosols on radiation. Accurate quantification of ADRF is the premise for understanding and predicting the Earth's climate state. To improve the estimation and evaluation of ADRF, numerous researchers have dedicated their efforts to developing a series of observations and models in recent decades. However, due to the limited availability of wide spatial and high-precision observations of aerosol optical characteristics, as well as an insufficient model description of aerosol properties and physical and chemical processes, the ADRF uncertainty is still high. This paper first reviews the spatio-temporal distribution of aerosol optical depth (AOD), single scattering albedo (SSA) and corresponding ADRF by using observations and models. The aerosol optical properties and ADRF show distinct discrepancies among various regions due to the impact of anthropogenic emissions and meteorological and climate conditions. In regions with rapid economic development, such as India, AOD demonstrates a long-term increasing trend with higher average values. However, regions influenced by environmental protection policies, such as North America and Europe, show a long-term decreasing trend in AOD, accompanied by lower average values. Based on site observations, most of Europe, North America, Africa, and Asia exhibit a significant long-term increasing trend in SSA. However, in seasons with biomass burning or dust outbreaks, specific regions, such as southern and southwestern China in late autumn and early spring, and northern and northwestern China in spring, exhibit a reduction in SSA. In the future, with the global and regional emissions of aerosols and precursors declining, ADRF is expected to weaken, highlighting the warming effect of greenhouse gases. However, the ADRF trend is closely linked to the present development level and trajectory of each region. Second, we systematically summarize the impacts of the influential factors on the ADRF, considering the AOD, SSA, surface albedo (SA), solar zenith angle (SZA), asymmetry factor (ASY), relative altitude between aerosols and clouds, and relative altitude between different types of aerosols. Subsequently, we proceed to review the sensitivities of ADRF to different influential factors, as well as the contributions of these factors to the overall uncertainty of ADRF, which indicate that ADRF is more sensitive to AOD and SSA while SSA emerges as the most significant source of uncertainty in ADRF due to the larger errors associated with its measurement. It should be noted that the uncertainty caused by SA and ASY cannot be ignored in polluted regions. Finally, from the perspective of observations and models, a brief outlook on improving the accuracy of ADRF evaluation is provided. In the future, advanced observation technologies, such as multi-angle, hyperspectral, polarized remote sensing observations, and precise in-situ measurements, should be developed to obtain more accurate information about the aerosols and environment. Furthermore, we need to properly combine various observations and models, including Earth system models, to improve the simulation of aerosols and their precursors. With improved understanding of aerosol-radiation interactions and refining techniques in observations and model simulations, the evaluation of ADRF will be more accurate.

期刊论文 2024-01-01 DOI: 10.1360/TB-2023-0375 ISSN: 0023-074X

为掌握拱形屋面积雪分布情况,降低其风雪灾害,通过对积雪现场进行调查,根据积雪实际分布与灾害情况,利用Fluent软件,建立拱形屋面的风致积雪分析模型,考虑空气相相对速度、空气相速度、空气相相对角速度、雪密度等影响因素,模拟拱形屋面风致积雪分布。通过分析,找出影响屋面积雪沉积的主要因素,建立风雪效用湍流模型,进而对拱形屋面积雪产生的压强统计数据开展详细分析,提出拱形屋面积雪不均匀分布系数取值的建议,以弥补我国现行规范对积雪均匀分布系数取值考虑较充分,对不均匀分布系数取值考虑不足的情况。

期刊论文 2021-10-18 DOI: 10.13204/j.gyjzG20122210

为掌握拱形屋面积雪分布情况,降低其风雪灾害,通过对积雪现场进行调查,根据积雪实际分布与灾害情况,利用Fluent软件,建立拱形屋面的风致积雪分析模型,考虑空气相相对速度、空气相速度、空气相相对角速度、雪密度等影响因素,模拟拱形屋面风致积雪分布。通过分析,找出影响屋面积雪沉积的主要因素,建立风雪效用湍流模型,进而对拱形屋面积雪产生的压强统计数据开展详细分析,提出拱形屋面积雪不均匀分布系数取值的建议,以弥补我国现行规范对积雪均匀分布系数取值考虑较充分,对不均匀分布系数取值考虑不足的情况。

期刊论文 2021-10-18 DOI: 10.13204/j.gyjzG20122210

针对多年冻土区埋地热油管道运行环境特点,建立管道停输时非稳态传热模型,利用FLUENT软件数值模拟了不同季节管道停输过程中大地温度场及管内油温随时间的变化规律,结合"焓-多孔度"技术,考虑了凝固潜热和自然对流换热对温降的影响,对管内原油凝固演化过程进行仿真。确定了合理停输时间,为管道安全启动提供理论指导。

期刊论文 2010-09-28
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