scholarly journals Phosphorus Retention of a Permeable Reactive Barrier Surpassed by an Unvegetated Artificial Pond

2021 ◽  
Vol 11 (1) ◽  
pp. 25
Author(s):  
Robert Summers ◽  
David Weaver
Keyword(s):  
Bauxite Residue ◽  
Construction Materials ◽  
Road Construction ◽  
Permeable Reactive Barrier ◽  
Environmental Standards ◽  
Reactive Barrier ◽  
Artificial Pond ◽  
Flow Through ◽  
A Minor ◽  
The Impact

An artificial pond bisected by a phosphorus (P) retentive permeable reactive barrier (PRB) alongside Forrest Highway, Coolup, Western Australia was designed to remove P from farmland runoff. The pond bed was made of subsoil and road construction materials likely to have a relatively high P sorption capacity, and there was no vegetation in the bed of the pond. Flow through the pond was intercepted by the PRB, constructed from a mixture of sand, coarse crushed limestone, and bauxite residue (with 10% phospho-gypsum). The effectiveness of P removal and the impact of the PRB was measured by comparing the concentration of contaminants immediately either side of the PRB with established standards, and against background levels in runoff from surrounding farmland. Using coarse limestone to increase flow through the PRB failed where permeability was insufficient to avoid overtopping of the PRB and the wall had to be lowered to allow by-pass and avoid collapse. The PRB was effective in removing total P (TP); however, the influent TP concentration was low (mean 0.19 mg L -1 ) because most P entering from farmland was retained in the shallow pond upstream of the PRB. Despite this, TP removal by the PRB was 53% (2009–2012). Occasionally, in spring when the pond was stagnant and anaerobic, P was released from the PRB. This minor P release coincided with a minor release of iron, consistent with anaerobic conditions found in the PRB. Although not designed to do so, the shallow pond upstream of the PRB reduced the TP concentration from farmland by 85% (mean 1.26 mg L -1 down to 0.19 mg L -1 ), mainly by reducing filterable reactive P concentration. Some elements (arsenic, cobalt, conductivity, fluoride, manganese, molybdenum, pH, selenium, uranium and vanadium) were increased by flow through the PRB, but were low relative to surrounding waters and environmental standards

Development of Permeable Reactive Barrier for Phosphorus Removal

2010 ◽  
Vol 636-637 ◽  
pp. 1365-1370 ◽  
Author(s):  
M. Oliveira ◽  
Ana Vera Machado ◽  
Regina Nogueira
Keyword(s):  
Hybrid Material ◽  
Phosphorus Removal ◽  
Sol Gel ◽  
Permeable Reactive Barriers ◽  
Permeable Reactive Barrier ◽  
Aluminium Isopropoxide ◽  
Reactive Barrier ◽  
Ft Ir ◽  
Flow Through ◽  
Ft Ir Spectroscopy

Permeable reactive barriers were developed for phosphorus removal. The barrier consists in an organic-inorganic hybrid material, which allows water and others species to flow through it, while selectively removes the contaminants. Polyethylene oxide (POE) and aluminium oxide (Al2O3) were used as the organic and the inorganic parts, respectively. The hybrid material was obtained by sol-gel reaction, using aluminium isopropoxide as inorganic percursor in order to attain Al2O3. The hybrid material produced was characterized by FT-IR spectroscopy and thermogravimetry. The previous tests for phosphorus removal have shown the effectiveness capacity of the developed material to remove it.

scholarly journals Remediation of Benzene and 1,2-Dichloroethylene in Groundwater by Funnel and Gate Permeable Reactive Barrier (FGPRB): A Case Study

Water ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 3336
Author(s):  
Chunyang Gao ◽  
Quanwei Song ◽  
Xingchun Li ◽  
Ligang Wang ◽  
Yong Zhai ◽  
...  
Keyword(s):  
Response Time ◽  
Maximum Concentration ◽  
Permeability Coefficient ◽  
Permeable Reactive Barrier ◽  
Injection Well ◽  
Delay Effect ◽  
Reactive Barrier ◽  
Monitoring Well ◽  
Concentration Time ◽  
The Impact

Funnel and gate permeable reactive barrier (FGPRB) is an effective method to treat groundwater pollution. In order to clarify the impact of FGPRB on groundwater dynamic conditions, this study takes a site pilot test as the research object and establishes an FGPRB downstream of a petrochemical industry. The results show that the concentrations of 1,2-dichloroethylene and benzene in the downstream groundwater, after setting FGPRB, are lower than the detection limit. The numerical simulation results show that after setting FGPRB, both point source and area source pollution can achieve a good delay effect, extending from about 27 d to about 65 d of response time, but changing the thickness and permeability coefficient has no obvious effect on the delay effect. The tracer test shows the average permeability coefficient of the medium from the injection well to the monitoring well after the construction of FGPRB decreases from 77.0 m/d to 31.2 m/d after the construction of FGPRB. The average seepage velocity from the injection well to the monitoring well decreased from 0.19 m/d to 0.078 m/d after the construction of FGPRB. At the same time, when the FGPRB is not built, the maximum concentration time from the injection well to the monitoring well is about 10 d. After the FGPRB is constructed, the maximum concentration time of the tracer received by the monitoring well is about 27 days. These results confirm that the establishment of FGPRB will change the hydrodynamic conditions of groundwater and delay the response time of pollutants in the monitoring well.

scholarly journals Analysis of Major Environmental Impact Categories of Road Construction Materials

2020 ◽  
Vol 12 (17) ◽  
pp. 6951
Author(s):  
Won-Jun Park ◽  
Rakhyun Kim ◽  
Seungjun Roh ◽  
Hoki Ban
Keyword(s):  
Life Cycle ◽  
Environmental Impact ◽  
Carbon Emissions ◽  
Construction Materials ◽  
Road Construction ◽  
Impact Categories ◽  
Toxicity Potential ◽  
Road Projects ◽  
Environmental Impact Categories ◽  
The Impact

To address the environmental problems associated with construction materials, the construction industry has made considerable efforts to reduce carbon emissions. However, construction materials cause several other environmental problems in addition to carbon emissions and thus, a comprehensive analysis of environmental impact categories is required. This study aims to determine the major environmental impact categories for each construction material in production stage using the life cycle assessment (LCA) technique on road projects. Through the review of life cycle impact assessment (LCIA) methodologies, the abiotic depletion potential (ADP), ozone depletion potential, photochemical oxidant creation potential, acidification potential, eutrophication potential, eco-toxicity potential, human toxicity potential, as well as the global warming potential (GWP) were defined as impact categories. To define the impact categories for road construction materials, major environmental pollutants were analyzed for a number of road projects, and impact categories for 13 major construction materials were selected as mandatory impact categories. These materials contributed more than 80% to the impact categories from an LCA perspective. The impact categories to which each material contributed more than 99% were proposed as specialization impact categories to provide basic data for use in the LCIA of future road projects.

The impact of calcium peroxide on groundwater bacterial diversity during naphthalene removal by permeable reactive barrier (PRB)

2019 ◽  
Vol 26 (34) ◽  
pp. 35218-35226 ◽  
Author(s):  
Fatemeh Gholami ◽  
Mahmoud Shavandi ◽  
Seyed Mohammad Mehdi Dastgheib ◽  
Mohammad Ali Amoozegar
Keyword(s):  
Bacterial Diversity ◽  
Permeable Reactive Barrier ◽  
Calcium Peroxide ◽  
Reactive Barrier ◽  
The Impact

scholarly journals Influences of benzene or toluene on dechlorination of perchloroethene and trichloroethene in a simulated zero-valent iron permeable reactive barrier

2018 ◽  
Vol 53 (2) ◽  
pp. 61-71 ◽  
Author(s):  
Liang Chen ◽  
YuLong Liu ◽  
Fan Xia ◽  
Fei Liu ◽  
Binghua Li
Keyword(s):  
Competitive Adsorption ◽  
Particle Surface ◽  
Zero Valent Iron ◽  
Permeable Reactive Barrier ◽  
Substantial Influence ◽  
Column Studies ◽  
Lower Affinity ◽  
Reactive Barrier ◽  
Flow Through ◽  
The Mean

Abstract Column studies were conducted to investigate the influence of benzene or toluene on the dechlorination of perchloroethene (PCE) and trichloroethene (TCE) in columns packed with zero-valent iron (ZVI) in order to simulate a permeable reactive barrier (PRB). Enhancive and inhibitive influences of benzene and toluene, respectively, on PCE and TCE reduction were observed within 10–80 pore volumes (PV) that flowed through the columns. However, such influences dissipated when the flow-through volume increased above 80 PV. The presence of benzene increased the mean dechlorination kobs of PCE and TCE by 7% and 6%, respectively; in contrast, the presence of toluene decreased the mean dechlorination kobs of PCE and TCE by 21% and 10%, respectively. We presumed that the more competitive adsorption between benzene and toluene in comparison to PCE and TCE on the ZVI particle surface might have caused the disparate influences. With a lower affinity for ZVI, benzene has no substantial influence on PCE and TCE adsorption on the ZVI particle surface. However, toluene has a higher affinity for ZVI and could compete with PCE and TCE by contacting the ZVI particle surface. Moreover, given benzene's higher polarity, it could also benefit electron transfer from ZVI to PCE and TCE.

scholarly journals Reducing the accumulation of residual deformations in the structural layers of pavements and in the subgrade soil through the use of stabilizing and adhesive additives

2018 ◽  
Vol 5 (4) ◽  
Author(s):  
Georgij Mygal ◽  
Nikita Mironov ◽  
Vakhtang Matua
Keyword(s):  
Asphalt Concrete ◽  
Soil Stabilization ◽  
Construction Materials ◽  
Road Construction ◽  
Turnaround Time ◽  
Road Pavement ◽  
Subgrade Soil ◽  
Stabilized Soil ◽  
Residual Deformations ◽  
The Impact

Road constructions are most relevant. This article provides data on the improvement of the properties of road construction materials, including those added to the soil: stabilized soil and adhesive asphalt concrete. Because of the impact of the above-mentioned additives, the accumulation of residual deformations in the structural layers of road products are reduced. The analysis of the market of the Russian Federation, which resulted in the identification of the following most preferred options for additives for research: ANT for soil stabilization and Amdor-10 and DAD-1 mark C for asphalt concrete. For asphalt concrete, several additivies were considered, since this is the most important structural layer in road pavement, perceiving the load from passing vehicles. This article provides comparative tables and graphs, which provide data on changes in the physic-mechanical properties of materials (soils and asphalt concrete) as a result of the application of the above additives. All tests were performed in accordance with the current regulatory documentation, and all the necessary requirements for the test materials were met. Were also obtained materials for testing. With the help of this device the possibility of resisting the accumulation of residual deformations is estimated. There is an imitation of situations in which materials are in real road. As a result, data were obtained that the use of stabilizing additives for soil and adhesive fabric reduces the accumulation of residual deformations and, as a result, increases the turnaround time between repairs.

CREDO RADON UA – INFORMATION MODEL FOR CALCULATION OF ROAD CONSTRACTION

2019 ◽  
pp. 34-42
Author(s):  
Volodymyr Karedin ◽  
Nadiya Pavlenko
Keyword(s):  
Design Process ◽  
Static Loading ◽  
Computer Aided Design ◽  
Experimental Studies ◽  
Construction Materials ◽  
Residual Deformation ◽  
Road Construction ◽  
Information Support ◽  
Existing Structures ◽  
Road Pavement

CREDO RADON UA software provides an automated calculation of the strength of the pavement structures of non-rigid and rigid types, as well as the calculation of the strengthening of existing structures. In the article, one can see the main features and functionality of the CREDO RADON UA software, the main points in the calculations according to the new regulations. Information support of the design process includes necessary databases, informational and helping materials that make up the full support of the pavement design process. The concept of CREDO RADON UA 1.0 software is made on the use of elasticity theory methods in calculations of initial information models of pavements. Performing optimization calculations, the roadwear in CREDO RADON UA is designed in such a way that no unacceptable residual deformation occurs under the influence of short-term dynamic or static loading in the working layer of the earth bed and in the structural layers during the lifetime of the structure. The calculation algorithms were made in accordance with the current regulatory documents of Ukraine. CREDO RADON UA software allows user to create information bases on road construction materials and vehicles as part of the traffic flow for calculations. The presented system of automated modeling makes it easier for the customer to control the quality of design solutions, to reasonably assign designs to layers of reinforcement, to quickly make comparisons of calculations of different designs for the optimal use of allocated funds. Prospects for further improvement of the program should be the results of theoretical and experimental studies on filling the databases, which are used as information support for automated design of road structures. Keywords: CREDO RADON UA, road, computer-aided design, repair project, road pavement, strengthening, construction, rigid pavement, elasticity module, a transport stream, calculation method, information support, dynamic or static loading.

scholarly journals Review: Impacts of shade on cattle well-being in the beef supply chain

2020 ◽  
Author(s):  
Lily N Edwards-Callaway ◽  
M Caitlin Cramer ◽  
Caitlin N Cadaret ◽  
Elizabeth J Bigler ◽  
Terry E Engle ◽  
...  
Keyword(s):  
Supply Chain ◽  
Heat Stress ◽  
Beef Cattle ◽  
Production Systems ◽  
Construction Materials ◽  
Well Being ◽  
Third Party ◽  
Ambient Temperatures ◽  
Stress Susceptibility ◽  
The Impact

ABSTRACT Shade is a mechanism to reduce heat load providing cattle with an environment supportive of their welfare needs. Although heat stress has been extensively reviewed, researched, and addressed in dairy production systems, it has not been investigated in the same manner in the beef cattle supply chain. Like all animals, beef cattle are susceptible to heat stress if they are unable to dissipate heat during times of elevated ambient temperatures. There are many factors that impact heat stress susceptibility in beef cattle throughout the different supply chain sectors, many of which relate to the production system, i.e. availability of shade, microclimate of environment, and nutrition management. The results from studies evaluating the effects of shade on production and welfare are difficult to compare due to variation in structural design, construction materials used, height, shape, and area of shade provided. Additionally, depending on operation location, shade may or may not be beneficial during all times of the year, which can influence the decision to make shade a permanent part of management systems. Shade has been shown to lessen the physiologic response of cattle to heat stress. Shaded cattle exhibit lower respiration rates, body temperatures, and panting scores compared to un-shaded cattle in weather that increases the risk of heat stress. Results from studies investigating the provision of shade indicate that cattle seek shade in hot weather. The impact of shade on behavioral patterns is inconsistent in the current body of research, some studies indicating shade provision impacts behavior and other studies reporting no difference between shaded and un-shaded groups. Analysis of performance and carcass characteristics across feedlot studies demonstrated that shaded cattle had increased ADG, improved feed efficiency, HCW, and dressing percentage when compared to cattle without shade. Despite the documented benefits of shade, current industry statistics, although severely limited in scope, indicate low shade implementation rates in feedlots and data in other supply chain sectors do not exist. Industry guidelines and third party on-farm certification programs articulate the critical need for protection from extreme weather but are not consistent in providing specific recommendations and requirements. Future efforts should include: updated economic analyses of cost versus benefit of shade implementation, exploration of producer perspectives and needs relative to shade, consideration of shade impacts in the cow-calf and slaughter plant segments of the supply chain, and integration of indicators of affective (mental) state and preference in research studies to enhance the holistic assessment of cattle welfare.

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