scholarly journals Modelling the Movement of some Mobile Hydrocarbons Below the Crop Rooting System Using Small-Scale Lysimeters with Undisturbed Soils

2020 ◽  
Vol 71 (9) ◽  
pp. 190-201
Author(s):  
Anca-Rovena Lacatusu ◽  
Horia Domnariu ◽  
Dora Marica ◽  
Cristian Paltineanu ◽  
Andrei Vrinceanu ◽  
...  
Keyword(s):  
Oil Spills ◽  
Tap Water ◽  
Infiltration Rate ◽  
Daily Basis ◽  
Vertical Movement ◽  
Breakthrough Curves ◽  
Small Scale ◽  
Limited Mobility ◽  
Undisturbed Soils ◽  
Btex Compounds

The presence of hydrocarbons in groundwater represents a serious risk of disease. This study tests the timing, concentration and amount of BTEX oil components during the oil vertical movement though small-scale lysimeters containing undisturbed soils of different textures and by simulating the fate of oil spills under continuous water application. Three soil types were studied: a sandy-textured, highly permeable Eutric Arenosol, AR-eu, a loamy/sandy-loamy textured Haplic Chernozem, CH-ha, and a loamy-clayey/clayey textured, swell-shrink, Luvic-Chernic Phaeozem, PH-ch-lv. Crude oil was applied as a batch application using an equivalent of 5 g oil /100 g of dry soil for a 0.02 m height in each lysimeter of the three soils studied. After oil-penetration into the soil, tap water was applied on a daily basis above the lysimeters according to infiltration rate. The breakthrough curves of the BTEX compounds show that the highest mobility in the investigated sandy AR-eu soils and loamy CH-ha soils was found for benzene followed by toluene. The other hydrocarbons only showed a limited mobility. There was no leachate from the swell-shrink PH-ch-lv soil. Soil texture and permeability thus play an important role in the movement of BTEX compounds toward the groundwater. After applying an amount of water of 200% from the total soil porosity, or an equivalent of 800-850 mm of precipitation, the leaching process did not end and there still is a leaching potential remained for these hydrocarbons. The highest amount leached per mm of effluent was also for benzene followed by toluene. There were highly significant, direct correlations between the amounts of the hydrocarbons leached and the cumulative effluent volume. The swell-shrink soils are still an effective barrier to hydrocarbons` movement toward groundwater. The BTEX aromatic hydrocarbons leached from the soils, if reach the groundwater, represent sources of pollution with severe risks for human health.

scholarly journals A Compact Weighing Lysimeter to Estimate the Water Infiltration Rate in Agricultural Soils

Agronomy ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 180
Author(s):  
Laura Ávila-Dávila ◽  
Manuel Soler-Méndez ◽  
Carlos Francisco Bautista-Capetillo ◽  
Julián González-Trinidad ◽  
Hugo Enrique Júnez-Ferreira ◽  
...  
Keyword(s):  
Agricultural Soils ◽  
Field Capacity ◽  
Mass Conservation ◽  
Infiltration Rate ◽  
Vertical Movement ◽  
Water Infiltration ◽  
Infiltration Capacity ◽  
Silty Loam ◽  
Rain Events ◽  
Weighing Lysimeter

Infiltration estimation is made by tests such as concentric cylinders, which are prone to errors, such as the lateral movement under the ring. Several possibilities have been developed over the last decades to compensate these errors, which are based on physical, electronic, and mathematical principles. In this research, two approaches are proposed to measure the water infiltration rate in a silty loam soil by means of the mass values of a lysimeter weighing under rainfall conditions and different moisture contents. Based on the fact that with the lysimeter it is possible to determine acting soil flows very precisely, then with the help of mass conservation and assuming a downward vertical movement, 12 rain events were analyzed. In addition, it was possible to monitor the behavior of soil moisture and to establish the content at field capacity from the values of the weighing lysimeter, from which both approach are based. The infiltration rate of these events showed a variable rate at the beginning of the rainfall until reaching a maximum, to descend to a stable or basic rate. This basic infiltration rate was 1.49 ± 0.36 mm/h, and this is because soils with fine textures have reported low infiltration capacity. Four empirical or semi-empirical models of infiltration were calibrated with the values obtained with our approaches, showing a better fit with the Horton’s model.

scholarly journals Impact of cleaning regimes on dental water unit contamination

2011 ◽  
Vol 9 (4) ◽  
pp. 647-652 ◽  
Author(s):  
Soad A. Abdallah ◽  
Ahmed I. Khalil
Keyword(s):  
High Speed ◽  
Tap Water ◽  
Daily Basis ◽  
Dental Chair ◽  
Dental Clinics ◽  
Significant Difference ◽  
Before And After ◽  
Hand Piece ◽  
Viable Bacteria ◽  
Dental Unit Waterlines

Microorganisms that have been identified in dental unit waterlines (DUWLs) are of concern because they can cause infections, especially in immunocompromised patients. This study aimed to assess the incidence of microbial contamination in DUWLs before and after intervention to reduce contamination, and to investigate the presence of coliforms, Escherichia coli and Pseudomonas aeruginosa. Water samples were collected aseptically from the waterlines. The high-speed hand-piece and dental chair units were served by one distillation apparatus, which was fed by the potable tap water of four dental clinics. Different interventions were used: chlorination, flushing before clinics and between patients, draining at the end of the day, and freshly distilled water on a daily basis. There was a significant difference between the level of contamination in the high-speed hand-piece (1.5–2.7 log CFU/ml) and dental chair unit water (2.0–3.5 log CFU/ml). Coliforms (0.9%) E. coli (0.9%) and Pseudomonas (1.8%) were detected during 2008. This study indicates the need to monitor water quality regularly and prevent stagnation in DUWLs to reduce the number of viable bacteria to <100 CFU/ml. We recommend flushing the DUWL for 2 min before the first patient and for 10–20 s between patients, flushing the dental unit at the end of the day and draining it overnight to reduce the development of biofilms, and chlorination of the DUWLs.

Development and Validation of a Design Tool for an Improved Pitot-Tube Jet-Pump Allowing Continuous Fluid-Fluid Separation

2021 ◽  
Author(s):  
Jan Deylen ◽  
Jessica Köpplin ◽  
Dominique Thevenin
Keyword(s):  
Oil Spills ◽  
Separation Efficiency ◽  
Scale Up ◽  
Design Tool ◽  
Pitot Tube ◽  
Polluted Water ◽  
Small Scale ◽  
Water Mixture ◽  
Jet Pump ◽  
Operation Conditions

Abstract A Pitot-tube Jet-Pump (PTJ pump) has been considerably modified and extended in order to continuously separate and transport liquids of different densities. As a first application, an oil-water mixture is considered in this work. The modified PTJ pump could be used as a primary separator for oil-polluted water (e.g., around off-shore platforms, after oil spills from ships), while additionally being able to transport the resulting fluid to further heaters, exchangers, centrifuges, distillation columns, etc., without necessitating additional machinery. The performance behavior of the separating PTJ pump (abbreviated SPP in what follows) has been first investigated with computational fluid dynamics (CFD), and then validated by comparison with experimental data acquired on a small-scale prototype. Based on these observations, a design tool has been developed to (i) predict performance and (ii) support proper device scaling. This tool is based on dimensionless parameters that are already employed for classical turbomachinery, similar to the Cordier chart. However, since the SPP works at an extremely low specific speed, its operating points lie outside the standard Cordier chart. To verify the accuracy of the design tool, a scale-up test has been conducted and validated by CFD, delivering a good agreement. A separation efficiency better than 99% has been obtained in the experiments for suitable operation conditions, while the numerical scale-up test reveals a head of 15.1 m and an oil content below 0.2% in the purified water at the High-Pressure Outlet.

Four planes of social being: more connections

2021 ◽  
pp. 127-144
Author(s):  
Priscilla Alderson
Keyword(s):  
Social Relations ◽  
Interdisciplinary Research ◽  
Policy Making ◽  
Interpersonal Relations ◽  
Oil Spills ◽  
Small Scale ◽  
Data Sets ◽  
Mortality And Morbidity ◽  
Critical Realist ◽  
Scale Data

Adverse mortality and morbidity effects of the huge oil spills in Bayelsa State, Niger Delta, illustrate the value of critical realism’s four planes of social being for organising complex findings and for combining large- and small-scale data sets. These planes cover every aspect of being human: bodies in relation to nature; interpersonal relations; larger social relations and structures; and inner human being in the mental-social-embodied personality. Chapter 5 also considers critical realist approaches to managing data-analysis: laminated systems analysis; interdisciplinary research and policy-making; critical realist theories about interdisciplinarity; overcoming barriers to interdisciplinarity, and interdisciplinary commitments. The detailed examples are about improving the physical health of people with a diagnosis of serious mental illness, and feminist-informed counselling after sexual assault.

Low-Cost Home Automation System for Physical Disability and Limited Mobility People

2021 ◽  
pp. 151-172
Author(s):  
José Irineu Ferreira Júnior ◽  
Paulo César do Nascimento Cunha ◽  
Vitor Gabriel Nunes Soares ◽  
Álvaro Sobrinho
Keyword(s):  
Latin American ◽  
Low Income ◽  
Physical Disability ◽  
Low Cost ◽  
Daily Basis ◽  
Automation System ◽  
Home Automation ◽  
Limited Mobility ◽  
Home Automation System ◽  
At Home

The general Latin American population with a physical disability or limited mobility has faced the daily basis challenge of having autonomy in home activities, with low-income or almost no-income. Needy Brazilian communities are examples of poor populations suffering from the lack of autonomy at home, aggravated by scarce financial resources. The authors developed a low-cost home automation system, aiming to assist people who live in Palmeira dos Indios city and Arapiraca city, needy communities located in the Northeast of Brazil. The system is composed of hardware and software components. The hardware comprises of microcontrollers used to actuate over electrical devices at home, while an Android application provides a simple graphical user interface (GUI) to control the devices using touch and voice commands by Bluetooth communication. They evaluated the system by implementing a home model and providing the home for four physical disability persons and one limited mobility person. They considered the system`s effectiveness, the system`s usability, and users` perceptions during the evaluation.

Laboratory Testing of a Flexible Boom for Ice Management

1993 ◽  
Vol 115 (3) ◽  
pp. 149-153 ◽  
Author(s):  
S. Lo̸set ◽  
G. W. Timco
Keyword(s):  
Oil Spills ◽  
The Arctic ◽  
Small Scale ◽  
Test Results ◽  
Offshore Structure ◽  
Video Cameras ◽  
Ice Concentration ◽  
Broken Ice ◽  
Ice Field ◽  
Force Components

Combatting oil spills in the Arctic is a major challenge. Drilling or producing oil or gas in the marginal ice zone (MIZ) may allow booms to be deployed upstream of an offshore structure to clear the water of ice, thereby enabling conventional oil spill countermeasures to be used. Such a boom would be kept in place by two ice-going service vessels or by moored buoys. SINTEF NHL and NRC have performed a number of small-scale tests with a flexible boom in the NRC ice basin in Ottawa. The purpose of the tests was to measure the effectiveness of using a flexible boom for collecting ice, and to determine the loads associated with collecting the ice. In the tests, various boom configurations were towed against a broken ice field consisting of ice pieces typically 50–100 mm across and 30 mm thick. The ice concentration was usually 10/10, but it was reduced to 8/10 and 5/10 for two tests. The boom was towed at speeds of 20 and 50 mm-s−1. Both the width of the boom and the slackness of the boom were varied over reasonable ranges. Two six-component dynamometers were used to support the boom. Thus, the force components on each end of the boom were measured. Further, two video cameras were used to record the effectiveness of each boom configuration. In this paper, the full results of this test program are presented and the application of the test results to the full-scale situation are discussed. The tests show that, under certain conditions, the use of boom is feasible for ice management in oil-contaminated water.

Burning of Oil Spills

1991 ◽  
Vol 1991 (1) ◽  
pp. 677-680 ◽  
Author(s):  
D.D. Evans ◽  
G.W. Mulholland ◽  
J.R. Lawson ◽  
E.J. Tennyson ◽  
M.F. Fingas ◽  
...  
Keyword(s):  
Crude Oil ◽  
Oil Spill ◽  
Technical Assistance ◽  
Oil Spills ◽  
Research Effort ◽  
Heat Radiation ◽  
Small Scale ◽  
Management Service ◽  
Environment Canada ◽  
The Impact

ABSTRACT The Center for Fire Research (CFR) at the National Institute of Standards and Technology (NIST) is conducting research related to safety in offshore drilling and oil spill pollution under joint funding from Minerals Management Service (MMS), U.S. Coast Guard, and the American Petroleum Institute. Technical assistance in measurement has been donated by Environment Canada. This research has focused on examining the phenomena associated with crude oil combustion and the impact of using burning as a spill response method. The process of burning crude oil on water as a means to mitigate oil spills has been investigated with a research effort combining both small-scale experiments and calculations. As a result of these studies, there has been increased understanding of the burning process, including burning rate, heat radiation, smoke emission, smoke composition, and smoke dispersion in the atmosphere. A key to gaining acceptance of burning as a spill response technique is the demonstration that favorable results obtained at laboratory scale can be shown to continue in test burns representing the size of fires expected in actual operations. Field-scale burn tests are being planned and coordinated jointly by MMS, API, USCG, and Environment Canada to document the use of burning technology under conditions simulating actual oil spill cleanup operations. The purpose of this project is to measure the effects of oil spill burning in laboratory and field tests.

HERDING AGENTS THICKEN OIL SPILLS IN DRIFT ICE TO FACILITATE IN SITU BURNING: A NEW TRICK FOR AN OLD DOG1

2008 ◽  
Vol 2008 (1) ◽  
pp. 673-679 ◽  
Author(s):  
Ian Buist ◽  
Tim Nedwed ◽  
Joe Mullin
Keyword(s):  
Oil Spills ◽  
Cold Water ◽  
Open Water ◽  
Small Scale ◽  
Us Army ◽  
Ice Coverage ◽  
Air Temperatures ◽  
Oil Spill Response ◽  
Ice Conditions

ABSTRACT In situ burning is an oil spill response option particularly suited to remote ice-covered waters. The key to effective in situ burning is thick oil slicks. In loose drift ice conditions oil spills can rapidly spread to become too thin to ignite. Fire booms can collect and keep slicks thick in open water; however, even light ice conditions make using booms challenging. A multi-year joint industry project was initiated to study oil-herding agents as an alternative to booms for thickening slicks in light ice conditions for in situ burning. Small-scale laboratory experiments were completed in 2004 and 2005 to examine the concept of using herding agents to thicken oil slicks among loose pack ice for the purpose of in situ burning. Encouraging results prompted further mid-scale testing at the US Army Cold Regions Research and Engineering Laboratory (CRREL), the Ohmsett facility, and the Fire Training Grounds in Prudhoe Bay, AK. The non-proprietary cold-water herder formulation used in these experiments proved effective in significantly contracting oil slicks in brash and slush ice concentrations of up to 70% ice coverage. Slicks in excess of 3 mm thick, the minimum required for ignition of weathered crude oil on water, were routinely achieved. Herded slicks were ignited, and burned equally well in both brash and slush ice conditions at air temperatures as low as −17°C. The burn efficiencies measured for the herded slicks were only slightly less than the theoretical maximums achievable for equivalent-sized, mechanically contained slicks on open water.

Shoreline Surface Washing Agent Test and Evaluation Protocol for Freshwater Use in the Great Lakes Region1

2003 ◽  
Vol 2003 (1) ◽  
pp. 319-325 ◽  
Author(s):  
Darrell R. Robertson ◽  
Jason H. Maddox
Keyword(s):  
Great Lakes ◽  
Oil Spill ◽  
Oil Recovery ◽  
Oil Spills ◽  
Federal State ◽  
Small Scale ◽  
Test And Evaluation ◽  
Primary Means ◽  
Labor Requirements ◽  
Freshwater Environments

ABSTRACT Although opportunities exist to use shoreline surface washing agents for oil spill removal in freshwater environments, this response technique is seldom tried because little is known about its insitu effectiveness and toxicity. In January 2000, the Federal Region V Regional Response Team chartered a Subcommittee of international, federal, state and industry representatives to develop a protocol for evaluating the test use of shoreline surface washing agents in freshwater environments on oil spills of opportunity in the Great Lakes Region. Currently, mechanical and manual recovery are the primary means of oil spill cleanup in freshwater environments which can be costly, labor intensive, and often results in limited oil recovery. Oil recovery inefficiency is related to shoreline composition and complexity that allow oil to cover, fill, and penetrate the substrate. Responders, with limited options, may compromise their efforts by leaving residual oil in the environment or expend a substantial effort sanitizing the shoreline, which can be more detrimental to the environment. The application of shoreline surface washing agents may improve recovery efficiency and ameliorate long term harm to freshwater shorelines if properly applied. Surface washing agents may also reduce labor requirements typically associated with diminishing returns from continued mechanical or manual cleanups required to achieve similar oil removal results. The RRT V Subcommittee developed a protocol for conducting small-scale insitu tests on the effectiveness and toxicity of surface washing agents to gain experience and confidence in its utility as a response tool in freshwater environments. The resulting protocol guides the user in assessing physical criteria, constraints and special considerations needed to determine if the use of two surface washing agents is appropriate. The protocol also includes procedures for test preparation and application and provides effectiveness, water quality and toxicity monitoring guidelines, data collection, booming, and oil recovery procedures.

Welfare implications of intertemporal marketing margin manipulation

2017 ◽  
Vol 119 (8) ◽  
pp. 1656-1671 ◽  
Author(s):  
Thomas Kopp ◽  
Bernhard Brümmer ◽  
Zulkifli Alamsyah ◽  
Raja Sharah Fatricia
Keyword(s):  
Value Chain ◽  
Crumb Rubber ◽  
Daily Basis ◽  
Parametric Estimation ◽  
Price Transmission ◽  
Small Scale ◽  
Data Set ◽  
Content Type ◽  
Subsequent Step ◽  
Welfare Implications

Purpose In Indonesia, rubber is the most valuable export crop produced by small scale agriculture and plays a key role for inclusive economic development. This potential is likely to be not fully exploited. The observed concentration in the crumb rubber processing industry raises concerns about the distribution of export earnings along the value chain. Asymmetric price transmission (APT) is observed. The paper aims to discuss these issues. Design/methodology/approach This study investigates the price transmission between international prices and the factories’ purchasing prices on a daily basis. An auto-regressive asymmetric error correction model is estimated to find evidence for APT. In a subsequent step the rents that are redistributed from factories to farmers are calculated. The study then provides estimations of the size of this redistribution under different scenarios. Findings The results suggest that factories do indeed transmit prices asymmetrically, which has substantial welfare implications: around USD3 million are annually redistributed from farmers to factories. If the price transmission was only half as asymmetric as it is observed, the majority of this redistribution was re-diverted. Originality/value This study combines the approaches of non-parametric and parametric estimation techniques of estimating APT processes with a welfare perspective to quantify the distributional consequences of this intertemporal marketing margin manipulation. Especially the calculation of different scenarios of alternative price transmissions is a novelty. The data set of prices on such a disaggregated level and high frequency as required by this approach is also unique.

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