Environmental Remediation Research Papers - Academia.edu (original) (raw)

- by
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- Indigenous Studies, Environmental Remediation, Mining, science and technology studies (STS)

In order to improve the efficiency of soil washing treatment of hydrocarbon contaminated soils, an innovative combination of this soil treatment technique with an electrochemical advanced oxidation process (i.e. electro-Fenton (EF)) has been proposed. An ex situ soil column washing experiment was performed on a genuinely diesel-contaminated soil. The washing solution was enriched with surfactant Tween(®) 80 at different concentrations, higher than the critical micellar concentration (CMC). The impact of soil washing was evaluated on the hydrocarbons concentration in the leachates collected at the bottom of the soil columns. These eluates were then studied for their degradation potential by EF treatment. Results showed that a concentration of 5% of Tween(®) 80 was required to enhance hydrocarbons extraction from the soil. Even with this Tween(®) 80 concentration, the efficiency of the treatment remained very low (only 1% after 24 h of washing). Electrochemical treatments performed th...

- by Emmanuel Mousset
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- Chemistry, Soil, Environmental Remediation, Environmental Management
- by Oznur Karaca
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- Environmental Science, Environmental Remediation, Hazardous Waste, Multidisciplinary

The objective of this study was to evaluate two bioremediation processes at scale (bioaugmentation and biostimulation) isolating and identifying soil-specific bacteria with the ability to bioaccumulate hexavalent chromium (Cr +6), for this we took a sample of 1 kg of soil from an industrial area of León, Guanajuato, from which the bacteria were isolated and identified: Moraxella bovoculi, Acinetobacter rudis, Enterobacter agglomerans, Moraxella bovis, Bulkholderia cepacia and Bulkholderia Mallei. Bioaugmentation was carried out with K2Cr2O7 at a concentration of 540 mg of Cr+6 with the bacteria identified and biostimulation was carried out with the consortium of microorganisms present in the soil with K2Cr2O7 concentration ranges of 440, 540 and 640 mg ofCr+6, using as a reference the NOM-147-SEMARNAT/SSA1-2004, treatments were maintained for 21 days. The biostimulation process was the most efficient for the removal of Cr+6, at a concentration of 640 mg of Cr+ had a maximum removal of 88%, while in the bioaugmentation process the maximum percentage of removal was 28.5 % with a concentration of 540 mg of Cr+ 6. It was determined that the process of biostimulation is the most suitable for the removal of Cr+6.

- by Erick Rodolfo Lopez Almanza and +1
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- Environmental Remediation, Biotechnology, Environmental Microbiology (Biology), Procesos De Bioremediacion

Ultra resolution chemical fingerprinting of dense non-aqueous phase liquids (DNAPLs) from former manufactured gas plants (FMGPs) was investigated using comprehensive two-dimensional gas chromatography coupled with time of flight mass spectrometry (GC × GC TOFMS). Reversed phase GC × GC (i.e. a polar primary column coupled to a non-polar secondary column) was found to significantly improve the separation of polycyclic aromatic hydrocarbons (PAHs) and their alkylated homologues. Sample extraction and cleanup was performed simultaneously using accelerated solvent extraction (ASE), with recovery rates between 76% and 97%, allowing fast, efficient extraction with minimal solvent consumption. Principal component analysis (PCA) of the GC × GC data was performed in an attempt to differentiate between twelve DNAPLs based on their chemical composition. Correlations were discovered between DNAPL composition and historic manufacturing processes used at different FMGP sites. Traditional chemical...

- by Laura McGregor
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- Engineering, Forensics, Technology, Environmental Remediation

The recent mining boom in the Northwest of Western Australia had lead to the region experiencing some of the highest rates of growth anywhere in the world. This recent increase in mining activity was in the wake of 10-15 years of lesser activity that resulted in poor maintenance and low grade facility upgrades. The primary restriction to growth industries in this region is in providing accommodation for the massive influx of workers. This investigation was a targeted assessment of the health risk of occupants to mould exposure in mine site accommodation buildings. The buildings are colloquially known as “Singlemens Quarters” or ”Dongas” and were located in the Pilbara Region of North-West Australia. Initial inspections were initiated by a flooding event; however, the investigation of the affected rooms identified several areas of existing mould damage. The main causes of the mould damage were refurbishments of wet bathroom areas into accommodation units and condensation from constant air-conditioning, which resulted in interior finishing’s & materials being below the dew point temperature. Extensive visible mould growth was manifest throughout the accommodation buildings. A detailed scope of works provided step by step instructions for workers with the aim of re-instating the mould affected accommodation to a normal or habitable condition. This study highlighted the need for a methodical and thorough process when assessing risk of mould exposure and in mould mitigation and mould remediation processes. The proper appropriation of resources in this project also established the financial and environmental benefits of this approach.

Physicochemical analyses were carried out on soil samples from four different waste dumpsites in the Federal University of Technology Akure (FUTA), Nigeria to ascertain the effects of the refuse dumpsites on soil and groundwater qualities. Dumpsite locations are Physics Laboratory (PHY), Post Graduate Hostel (PG), School of Earth and Mineral Science (SEMS) and Staff Quarters (STQ). Soil samples collected at distances 0 (dumpsite), 10 and 20 m intervals away from the dumpsite were analyzed and at depths 10, 20 and 30 cm. Parameters determined include pH, Electrical Conductivity (EC), Magnesium (Mg), Calcium (Ca), Sodium (Na), Phosphorus (P), Nitrogen (N), Potassium (K), Organic Carbon (OC), Organic Matter (OM) and heavy metals such as Copper (Cu) and Lead (Pb) and subjected to relevant statistical analysis. Most of the parameters analyzed indicated pollution and were below the Food and Agricultural Organization (FAO) limits. P and Mg concentrations ranged from 1.19 to 1.25mg/kg and 3.17 to 13.61mg/kg respectively which indicated pollution. Out of heavy metals analyzed, Cu was 1.75mg/kg and Pb was not detected. Statistical analysis indicated signicant differences at 95% level. The result showed that the soil samples were mildly polluted and therefore not suitable for crop production.

Oil spill is one of the major devastating issues Nigerian petroleum industry is facing today. Water (both fresh and salt) contamination is one of the environmental parts affected by oil spill as a result of industrial activities. This project was aimed at finding how a simple and cheap water filter bed can be designed using locally sourced materials such as maize cobs, sand, and charcoal. The filter was then used to purify crude oil contaminated water. This purification type is based on two major physical processes such as " absorption " and " adsorption ". The filter performance was assessed by analyzing water pH, turbidity, TDS, and nitrate content using computer Vernier probes. Total hydrocarbon contents, and heavy metals analysis were also done using Gas Chromatography and Mass Spectrometer (GC-MS) and Atomic Absorption Spectroscope (AAS), respectively. The obtained results showed a high filter capability of removing heavy metal contaminants in water. A percentage removal of 44%, 25%, 51%, and 88.5% of cadmium, copper, cobalt and zinc, respectively was recorded. The filter also showed a high capability in removing organic contaminants and also reducing turbidity, TDS and nitrate content. The filter was also able to treat contaminated water from a pH of 5.25 to 7.33 approximately.

In the process of oil and gas extraction, the oil/gas/water mixture is brought to the surface through well tubing. The mixture then passes through a separator, which removes the gas. With further processing the gas is transported to a gas purification plant where the various gas fractions are separated and purified.
The oil stream is further treated to remove the geological formation water that is extracted with the oil and gas. After separation from the oil, the formation water, also termed production water at this stage, is usually treated and discharged to the sea/ocean.
Sand and oily sludge from the reservoir are also removed during this treatment.
Solids deposit on the internal surfaces of the oil field extraction and production equipment, such as tubulars, other pipes, heat exchangers and pumps

- by mam sab
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- Environmental Remediation, Waste-to-Energy, Waste Management

Industrial Revolution resulted in serious environmental pollutions such as heavy metals and other dangerous waste pollution in the soil and water. Heavy metals pollution has become one of the most serious environmental problems. The effects of heavy metals on human health can cause serious diseases and even lead to death. Phytoremediation is one of the bioremediation techniques can be used as an alternative solution for heavy metal remediation process in heavy metal polluted areas. Phytoremediation technology based on the use of metal-accumulating plants. The selection of plant types for phytoremediation becomes an important consideration to make the remediation process more effective and efficient as well as to prevent the plants from being consumed. The use of non-edible and non-commercial fast growing with high biomass plants as remediating plants can be an alternative solution and cover crops that have characteristics that meet with this purpose. This short review tries to give some information about the potential use of cover crops for the heavy metal remediation process from the soils. Previous studies showed that several non-edible plants that can be used as cover crops are potential for phytoremediation process of heavy metals contaminated soils.

Las directrices para la remediación de suelos son recomendaciones generales orientadas al empleo de biotecnologías que han demostrado su capacidad para el saneamiento y la recuperación de suelos contaminados con hidrocarburos totales de petróleo. Con base en una revisión bibliográfica, se explican los mecanismos biológicos, ecológicos, económicos y sociales que sustentan la capacidad remediadora de diversas técnicas, lo que permite seleccionar los métodos adecuados de acuerdo con el nivel de afectación. En este trabajo, se presentan los datos requeridos para fijar las directrices y elegir los mecanismos de remediación de los suelos contaminados con hidrocarburos totales de petróleo.

BACKGROUND: When direct current (DC) is used in electrocoagulation processes, an impermeable oxide layer may form on the cathode and corrosion of the anode may occur due to oxidation. This prevents effective current transfer between the anode and cathode, so the efficiency of the electrocoagulation process declines. These disadvantages of DC have been reduced by adopting alternating current (AC). The main objective of this study is to investigate the effects of AC and DC on the removal of fluoride from water using an aluminum alloy as anode and cathode.RESULTS: Results showed that removal efficiencies of 93 and 91.5% with energy consumption of 1.883 and 2.541 kWh kL−1 was achieved at a current density of 1.0 A dm−2 and pH 7.0 using an aluminum alloy as electrodes using AC and DC, respectively. For both AC and DC, the adsorption of fluoride fitted the Langmuir adsorption isotherm. The adsorption process follows second-order kinetics and temperature studies showed that adsorption was exothermic and spontaneous in nature.CONCLUSIONS: The aluminum hydroxide generated in the cell removed the fluoride present in the water and reduced it to a permissible level thus making it drinkable. It is concluded that an alternating current prevents passivation of the aluminum anode during electrocoagulation and avoids the additional energy wasted due to the resistance of the aluminum oxide film formed on the anode surface. Copyright © 2010 Society of Chemical Industry

- by Subramanyan Vasudevan and +2
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- Engineering, Environmental Engineering, Chemical Engineering, Environmental Remediation

Brownfield areas are a major concern in Europe because they are often extensive, persistent in time andcompromise stakeholders’ interests. Moreover, due to their complex nature, from the decision-makingpoint of view, the regeneration of brownfields is a challenging problem requiring the involvement of thewhole range of stakeholders. Many studies, projects and organisations have recognised the importanceof stakeholder involvement and have promoted public participation. However, comprehensive studies providing an overview of stakeholders’ perceptions, concerns, attitudes and information needs when dealing with brownfield regeneration are still missing. This paper presents and discusses a participatory methodology applied to stakeholders from five European countries to fill this research gap, to develop a system to support the categorisation of the needed information and to support the understanding of which typology of information is the most relevant for specific categories of stakeholder also in relation with their concerns. The engagement process consists of five phases: (i) planning and preparatory work, (ii) identification of stakeholder categories, (iii) engagement activities (e.g. focus groups and workshops), (iv) submission of a questionnaire and (v) provision of feedback to the involved stakeholders. Thanks to this process, appropriate stakeholders have been identified as well as their perceptions, concerns, attitudes and information needs. Stakeholders’ perceptions proved to be different according to the country: German and Italian stakeholders perceive brownfields as complex systems, where several issues need to be addressed, while Romanian stakeholders consider contamination as almost the only issue to be addressed; Czech and Polish stakeholders address an intermediate number of issues. Attitudes and concerns seemed to be quite similar between countries. As far as information needs are concerned, similarities between some groups of stakeholders have been noticed: site owners and problem holders are primarily interested in information on planning and financing, while authorities and services providers are interested in more technical aspects like investigation, planning and risk assessment. Some outstanding outcomes emerged from the scientific community and research group, which showed an interest for remediation strategies and options and socio-economic aspects. The research outcomes allowed to create a knowledge base for the future development of tailored and customised approaches and tools for stakeholders working in the brownfield regeneration field.

- by Marco Pesce and +2
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- Information Systems, Environmental Remediation, Stakeholders, Land management

The risk analysis was performed to study the bioavailability and eco-toxicity of heavy metals in biochar
obtained from pyrolysis of sludge of pulp and paper mill effluent treatment plant. The sludge was pyrolyzed
at different temperatures (200–700 C) and the resultant biochar were analyzed for fractionation of
heavy metals by sequential extraction procedure. It was observed that all the heavy metals get enriched
in biochar matrix after pyrolysis, but the bioavailability and eco-toxicity of the heavy metals in biochar
were significantly reduced as the mobile and bioavailable heavy metal fractions were transformed into
the relatively stable fractions. Moreover, it was observed that the leaching potential of heavy metals
decreased after pyrolysis and the best results were obtained for biochar pyrolyzed at 700 C.

- by Parmila Devi
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- Environmental Remediation, Water and wastewater treatment, BIOCHAR, Heavy metals

Crude oil continues to impact many nations as it is among the major sources of fuel. Its role in making life in modern societies comfortable cannot be overemphasized as it is readily available and easy to use. Contamination resulting from its use in industries such as mining, transportation and petroleum especially soil contamination cannot be overlooked. Soil pollution resulting from oil contamination can be seen as being among the twenty-first-century vulnerabilities because if not well taken care of the consequences can be devastating. Soil contamination is of interest in most societies because it affects both the environment and humans. This review highlights common sources of soil pollution and their effects, oil waste disposal methods, soil remediation techniques that are well established and those still in their infancy. Such techniques include bioremediation such as phytoremediation and landfarming, where percent removal of contaminated soils was reported from 68% to 89 % in 40 days to 1 year, respectively; physical methods such as excavation and incineration (75-86% removal); chemical methods such as oxidation (48 % by Fenton process); and photocatalysis (67% using titanium dioxide). The choice of remediation in mining, transportation and petroleum industries depends on the urgency and hazardous effects of the pollutant. In Zambia, Mopani Copper Mines uses landfarming as a means to mitigate large amounts of soil contaminated with oil wastes, but the process is slow. In the proposed research, photocatalysis coupled with adsorption of oil on clay will be used to assess the effectiveness of this emerging technology to quicken the degradation of oil in soils. Clay will be incorporated with metal ions and with hydrophobic groups to enhance light absorption and oil-clay interaction, respectively. Photochemical remediation techniques for remediation of soils polluted with oil have attracted considerable interest as the processes are reported to enhance the degradation of oils in soil compared to the biological and physical methods. The extent of photo-degradation of oil waste will be evaluated using the Soxhlet technique by determining the percent residual oil. The importance of remediating contaminated soil in any nation cannot be overemphasized as consequences of not remediating this precious resource might be devastating. Since economic development through industrialization will continue, there is need to constantly improve on methods of mitigating the impact of wastes on the environment, especially in developing countries, where engineering of cheap, nontoxic materials for soil remediation is paramount.

- by Todd Johnson and +1
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- Environmental Remediation, Contamination and remediation

Research questions
Alphonso variety of mango is world famous because of its taste and longer shelf life.
However, increasing use of chemical pesticides and fertilizers for longer duration has
shown deterioration in the taste and hence marketability of the fruit. There are several
incidence of rejecting batches of mango fruits, in the international market because of
presence of heavy metal traces above the internationally agreed norms. Therefore, it is
well felt need that mango growers in Ratnagiri district should reduce the use of
Chemical pesticides responsible for bioaccumulation of heavy metal traces. It is
necessary to replace such chemical pesticides by biopesticides like Karanj, Neem, Cow
urine etc.
Can it be possible? If such replacement is effective, what would be the cost? Can we
prepare a strategy to promote use of biopesticides and avoid heavy metals
concentrations?
With such questions in the mind the present study would be carried out. Such study may
start with the understanding of quantity of pesticides used in the district and to carry out
impact analysis of the same. The study may propose appropriate strategy to reduce the
use of chemical pesticide and to encourage use of biopesticides. For this, the study
entitled, "Impact of Selected chemical Pesticides on the Mango plantations ecology a
case study of Ratnagiri District, Maharashtra", has been undertaken.
1.4 Hypothesis
Use of chemical pesticides on mango cultivation would cause significant degradation of
ecosystem. It may be checked by adopting organic methods of cultivation for which
acceptance level among the mango growers in Ratnagiri district is quite promising.
1.5 Objectives
 To assess impacts of selected chemical pesticide (Imidaclorid, Cypermethrin,
Quinalphos and Hexaconezole) and heavy metals on mango plantation.
 To study effectiveness of biopesticides to control frequently occurring pest on
mango plantation in the study area.
 To carry out comparative cost benefit analysis of chemical and biopesticides used in
mango orchards.
 To design appropriate strategy for replacing chemical pesticides with bio control
methods.

- by Dr. Vinaya Tari
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- Ecotourism, Environmental Remediation, Ecology, Phytoplankton

A atividade de revenda de combustíveis pode gerar contaminação do solo e da água subterrânea devido a vazamentos que, em geral, ocorrem na área de tanques subterrâneos, bombas de abastecimento e/ou linhas de distribuição. Uma das formas de tratar esta contaminação é através da remediação termal, técnica que consiste no aquecimento do solo muito utilizada no exterior e que está sendo difundida no Brasil. Este trabalho apresenta as propriedades do solo de maior relevância para a aplicação da técnica, que são as propriedades hidráulicas, elétricas e térmicas, nas condições saturada e não saturada; e a relação destas propriedades com a operação de sistemas de remediação termal em campo. É dada ênfase nas características de solos tropicais, que cobrem cerca de 60% do território brasileiro. O trabalho descreve as principais técnicas de remediação termal disponíveis no Brasil, as condições e fatores que influenciam a eficiência de cada técnica, os impactos potenciais no solo e vizinhanças, e a legislação pertinente.

The study was carried out as a kind of documentation of the used of wild edibles plants by the people in Bataw village, East Jaintia Hills. The results show that there are 35edible plants and belonging to 26 families being taken by the people of Bataw village as food. The mode of utilisation of wild edible plant includes 12 plant species used as vegetables, 11 species eaten as raw and 12 species consume as raw and as well as vegetable. The vast overexploitation of these indigenous wild edible plants has led to the over decline of these species. Therefore steps should be taken to protect such resources and further inventories need to undertake to understand their nutritional benefits and their long term sustenance.

- by Donboklang Marbaniang and +2
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- Environmental Science, Environmental Remediation, Wild edibles, Botany of Useful Plants

Oil spill is one of the major devastating issues Nigerian petroleum industry is facing today. Water (both fresh and salt) contamination is one of the environmental parts affected by oil spill as a result of industrial activities. This project was aimed at finding how a simple and cheap water filter bed can be designed using locally sourced materials such as maize cobs, sand, and charcoal. The filter was then used to purify crude oil contaminated water. This purification type is based on two major physical processes such as “absorption” and “adsorption”. The filter performance was assessed by analyzing water pH, turbidity, TDS, and nitrate content using computer Vernier probes. Total hydrocarbon contents, and heavy metals analysis were also done using Gas Chromatography and Mass Spectrometer (GC-MS) and Atomic Absorption Spectroscope (AAS), respectively. The obtained results showed a high filter capability of removing heavy metal contaminants in water. A percentage removal of 44%, 25%, 51%, and 88.5% of cadmium, copper, cobalt and zinc, respectively was recorded. The filter also showed a high capability in removing organic contaminants and also reducing turbidity, TDS and nitrate content. The filter was also able to treat contaminated water from a pH of 5.25 to 7.33 approximately.

The use of biochar has been suggested as a means of remediating contaminated soil and water. The
practical applications of conventional biochar for contaminant immobilization and removal however
need further improvements. Hence, recent attention has focused on modification of biochar with novel
structures and surface properties in order to improve its remediation efficacy and environmental benefits.
Engineered/designer biochars are commonly used terms to indicate application-oriented, outcomebased
biochar modification or synthesis. In recent years, biochar modifications involving various
methods such as, acid treatment, base treatment, amination, surfactant modification, impregnation of
mineral sorbents, steam activation and magnetic modification have been widely studied. This review
summarizes and evaluates biochar modification methods, corresponding mechanisms, and their benefits
for contaminant management in soil and water. Applicability and performance of modification methods
depend on the type of contaminants (i.e., inorganic/organic, anionic/cationic, hydrophilic/hydrophobic,
polar/non-polar), environmental conditions, remediation goals, and land use purpose. In general,modification to produce engineered/designer biochar is likely to enhance the sorption capacity of biochar
and its potential applications for environmental remediation.

- by Anushka Upamali Rajapaksha and +1
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- Environmental Remediation, BIOCHAR, Heavy metals

The contamination of soils by metals becomes a global concern due to the possibility of potential ecotoxic influence to plants and animals with the likely risk of accumulation in the human food chain. Soil with contaminants can either be left as is in the site or can be moved to a secure disposal site with continuous monitoring to limit any possible subsequent contamination. However, the distribution of contaminated sites around the world is increasing, e.g., (a) in China, about 50 housands ha of the land area associated with mining activities are thought to be degraded each year with metal; (b) in the United States, 50 million m3 of soil are estimated to be contaminated with metals; and (c) in Europe, several million ha of agricultural lands are reported to be polluted with metal. Hence, decontamination of the soil is considered as the economically beneficial option for the re-exploitation of the contaminated sites. The available remediation techniques include solidification, stabilization, flotation, soil washing, electro-remediation, bioleaching, and phytoremediation.
The book starts with an overview of the effects of metal intrusion on the natural properties of soils. The metal-loading extent in soils due to some notable anthropogenic activities is discussed in Chaps. 2 and 3. The test methods used to evaluate the metal content in the contaminated soils is discussed in Chap. 4. The following chapter provides a comparative discussion on the national and international legislative regulations so far proposed or being implemented to restrict the intrusion of toxic metal contaminants in soils. The remediation techniques in practice to manage the metal-contaminated soils are included as the core part of the book (Chaps. 6, 7, 8, 9, and 10). The final section of the book discusses the risk factors and cost modeling of the remediation options for the treatment of metal-contaminated soils.

- by M. Azizur Rahman
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- Environmental Remediation

Abstrak: Bioremediasi merujuk pada penggunaan secara produktif proses biodegradatif untuk menghilangkan atau mendetoksi polutan yang mencemari lingkungan dan mengancam kesehatan masyarakat. Biasanya sebagai kontaminan tanah, air dan sedimen dengan memanfaatkan mikroorganisme. Sebelum proses bioremediasi, isolasi dan seleksi awal akan menentukan bakteri mana yang sesungguhnya berperan dan berpotensi untuk dikembangkan dan dimanfaatkan secara khusus dalam penanganan pencemaran minyak/lemak. Tujuan dari isolasi dan identifikasi Bacillus sp. ini adalah untuk mengetahui jenis-jenis uji biokimia yang digunakan, serta mengidentifikasi bakteri Bacillus sp. sebagai bakteri pendegradasi kontaminan minyak pada proses bioremediasi. Uji biokimia ini mencakup uji fermentasi karbohidrat, uji hidrolisis pati (amilolitik), uji lipolitik, uji methyl red, uji
Voges-Proskauer, uji oksidase, uji katalase, uji indol, uji sitrat, uji proteolitik, uji urease, uji hidrogen sulfida (H2S), uji selulase dan uji protease. Mekanisme biodegradasi hidrokarbon minyak bumi oleh bakteri Bacillus sp. menggunakan hidrokarbon minyak bumi sebagai sumber karbon dan energi. Proses selanjutnya, bakteri memproduksi enzim yang dapat mendegradasi hidrokarbon minyak bumi. Penambahan biosurfaktan dapat meningkatkan degradasi hidrokarbon, terutama hidrokarbon dengan panjang rantai kurang dari 9 sulit didegradasi karena senyawa ini bersifat
toksik.
Kata kunci: Bacillus sp., Bioremediasi, Hidrokarbon, Isolasi, Uji Biokimia

- by Muhammad Nofal
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- Engineering, Environmental Engineering, Environmental Remediation, Bioremediation

Heterogeneous photocatalysis is a promising technology especially for environmental remediation. Despite more than a decade of worldwide research in developing photocatalytic efficiency improving techniques, many questions regarding the large scale application of photocatalytic reactors still remain unanswered. Recently, improving the photocatalytic efficiency has gained scientific attention because it might lead to more economical and robust photocatalytic operation for environmental remediation. In this review, fundamental and comprehensive assessments of the photocatalytic concepts and their applications for environmental remediation are reviewed. The existing challenges and strategies to improve the photocatalytic efficiency are discussed. Further, recent developments and future research prospects on photocatalytic systems for environmental applications are also addressed.

- by Barney Bedford
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- Environmental Remediation, Clay Minerals

Biochars are biological residues combusted under low oxygen conditions, resulting in a porous, low density carbon rich material. Their large surface areas and cation exchange capacities, determined to a large extent by source materials and pyrolysis temperatures, enables enhanced sorption of both organic and inorganic contaminants to their surfaces, reducing pollutant mobility when amending contaminated soils. Liming effects or release of carbon into soil solution may increase arsenic mobility, whilst low capital but enhanced retention of plant nutrients can restrict revegetation on degraded soils amended only with biochars; the combination of composts, manures and other amendments with biochars could be their most effective deployment to soils requiring stabilisation by revegetation. Specific mechanisms of contaminant-biochar retention and release over time and the environmental impact of biochar amendments on soil organisms remain somewhat unclear but must be investigated to ensure that the management of environmental pollution coincides with ecological sustainability.

Sur la Grande -Terre de Nouvelle-Calédonie, les anciennes décharges minières et les sols mis à nus par les exploitations ont largement contribué, et contribuent encore, à alimenter en débris rocheux (charge solide) les cours d’eau, au point que certains cours d'eau sont
considérablement engravés. Ce sur-engravement a, entre autres, pour conséquence une remontée et l’élargissement des lits des rivières et des creeks augmentant ainsi l’aléa inondation et les risques pour les personnes et les biens. Il entraîne de surcroit une altération
des écosystèmes aquatiques, une détérioration des alimentations en eau potable, des apports de boue sur les cultures lors des inondations, des endommagements des voies de communication et affecte pratiques et activités coutumières.
L’objectif du projet « Gestion du Passif minier » financé par le CNRT, est d’élaborer un guide méthodologique visant à aider la mise en place de remédiations au phénomène de surengravement qui soit adapté à chaque contexte local. La remédiation du fait de son interaction avec la société et les populations ne saurait être abordée, pour être efficace, que
sous ses aspects techniques.

- by A. Recking and +1
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- Environmental Remediation, Mining, New Caledonia, Flooding

Sur la Grande-Terre de Nouvelle-Calédonie, les anciennes décharges minières et les sols mis à nus par les exploitations ont largement contribué, et contribuent encore, à alimenter en débris rocheux (charge solide) les cours d’eau, au point que certains cours d'eau sont considérablement engravés. Ce surengravement a pour conséquence, entre autres, un exhaussement et l’élargissement des lits des rivières et des creeks augmentant ainsi l’aléa inondation et les risques pour les personnes et les biens. Il entraîne de surcroit une altération des écosystèmes aquatiques, une détérioration des alimentations en eau potable, des apports de boue sur les cultures lors des inondations, des endommagements des voies de communication et affecte les pratiques et activités coutumières.
Le présent guide méthodologique, produit à l’issue du projet « Gestion du Passif minier » financé par le CNRT, vise à aider la mise en place de remédiations au phénomène de surengravement qui soient adaptées à chaque contexte local. La remédiation du fait de son interaction avec la société et les populations ne saurait être abordée, pour être efficace, que sous ses aspects techniques. C’est pourquoi une approche conjointe mobilisant des sciences physiques et humaines a été mise en oeuvre.

The electrochemical production of hydrogen peroxide (H2O2) by 2-electron oxygen reduction reaction (ORR) is an attractive alternative to the present complex anthraquinone process. The objective of this paper is to provide a state-of-the-arts review of the most important aspects of this process. First, recent advances in H2O2 production are reviewed and the advantages of H2O2 electrogeneration via 2-electron ORR are highlighted. Second, the selectivity of the ORR pathway towards H2O2 formation as well as the development process of H2O2 production are presented. The cathode characteristics are the decisive factors of H2O2 production. Thus the focus is shifted to the introduction of commonly used carbon cathodes and their modification methods, including the introduction of other active carbon materials, hetero-atoms doping (i.e., O, N, F, B, and P) and decoration with metal oxides. Cathode stability is evaluated due to its significance for long-term application. Effects of various operational parameters, such as electrode potential/current density, supporting electrolyte, electrolyte pH, temperature, dissolved oxygen, and current mode on H2O2 production are then discussed. Additionally, the environmental application of electrogenerated H2O2 on aqueous and gaseous contaminants removal, including dyes, pesticides, herbicides, phenolic compounds, drugs, VOCs, SO2, NO, and Hg0, are described. Finally, a brief conclusion about the recent progress achieved in H2O2 electrogeneration via 2-electron ORR and an outlook on future research challenges are proposed.

- by Wei Zhou
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- Environmental Remediation, Electrochemistry, Carbon, Literature Review

El Hidrógeno Molecular (H2) es considerado el antioxidante mas poderos!
Es la fuente de energía por excelencia para las células que le permite desempeñar por completo todas sus funciones, tales como: desintoxicar, sanar, reparar y regenerar a si misma. Excelente tanto para los atletas profesionales como para personas con todo tipo de padecimientos, y así como para niños o mujeres embarazadas. En Japón son mas de 50 años que se reconoce de forma oficial su efectividad para tratar mas de 170 padecimientos distintos. Por ser el átomo mas pequeño logra penetrar todas las células del cuerpo humano y en tan solo 45 días poder regenerar órganos como el hígado, páncreas, riñones entre otros y lograr recuperar salud y bienestar de forma estable.

A total of five borehole samples were collected from five towns in Owerri metropolis, South-eastern Nigeria and subjected to physio-chemical analysis using atomic absorption spectrophotometer (AAS) and other standard equipment with the aim of characterizing and analysing the groundwater quality indicators. These quality indicators are namely: pH, temperature, total hardness, turbidity, electrical conductivity, total dissolved solids, total suspended solids, dissolved oxygen, Ca2+, Mg2+, Na+, K+, HCO3-, SO42-, Cl-, NO3-, Fe2+, Zn2+, Pb2+, Cu2+, Mn2+, and Cr2+. With the aid of geochemical diagrams acquired using Aquachem 2014.2, we classified the groundwater samples into their respective hydrogeochemical facies, identified their relative similarity and demonstrated the irrigability of the groundwater. The results showed that the groundwater quality indicators occur in the groundwater in amounts that fall within their respective permissible limits as set by World Health Organization (WHO) Drinking Water Standard, and therefore ascertained the groundwater portable and suitable for drinking. The pH of the groundwater has a mean value of 6.7 with a standard deviation of 0.26. The relative abundance of the majority of cations follows this sequence - Na+ > Ca2+ > K+ > Mg2+, while that of the anions follow this sequence - HCO3- > Cl- > SO42- > NO3-. Heavy metals constituents of the groundwater follow this order of relative abundance - Zn2+ > Fe2+ > Mn2+ > Cu2+ > Cr2+ > Pb2+. Three hydrogeochemical facies were identified in the area and they are: the Na+—Cl- water type, the Mixed Ca2+-Na+-HCO3- water type and the Ca2+-Mg2+-HCO3- water type. Great similarities were identified between the geochemical composition of the samples and they are all evidently suitable for irrigation purposes. The TDS level and concentration of Ca2+, Mg2+ and Cl- demonstrated the freshness and softness of the groundwater, with no laxative effects. From series of computations and plots, silicate weathering and seawater intrusion were deduced to be the dominant factors controlling the groundwater chemistry, though there is evidence of poor rock dissolution – immature water-rock equilibrium.

In mining operations carried out below the water table, mine area could potentially affect the surrounding. With further deepening of the mine and quarry, the drawdown can impact on water supply wells and base flow. The variation in radius of influence under confined and unconfined aquifer condition is assessed using a hypothetical case study with three operational quarry sites. Average pit-wise radius of influence (R0) for the pit mine, under unconfined and confined aquifer conditions is 963 m and 61 km, respectively, whereas effective radius (Re) for total (cumulative) excavated mine area is 1.7 and 146 km, respectively. It means that the maximum and minimum value of overall impact/influence for the unconfined aquifer lies in-between 963 m and 1.7 km. Similarly that the maximum and minimum value of overall impact/influence for the confined aquifer lies in-between 61 and 146 km. Meanwhile, Re or effective radius for total (cumulative) excavated area seems more appropriate from evaluation viewpoint due to the overlapping (superposition) concentric mining quarries. Thus, assessment of quarry-wise and total radius of influence is of importance to fulfil targeted production, economically with minimum interruptions as part of the mine planning. Moreover, it helps us to assess, monitor and regulate the impact of a mine-dewatering program in the area. Also, the pumping test is often used to estimate radius of influence; it can trigger the inflow or radius of influence. Estimate of the radius of influence using analytical equation mainly independent of discharge/abstraction from the aquifer stands as a preferred choice for the prediction of radius of influence at the quarry/mine pit. There is a strong rationale that policies should be informed by such analytical assessment because it helps us to prevent or minimize negative impacts as part of regulation and pit-mining management and are useful tools for practitioners to design economically efficient and cost-effective in situ groundwater remediation systems, to contain contaminant plumes, to evaluate the surface–subsurface water interaction and to verify numerical models.

Abstrak : Biodegradasi kinetika digunakan untuk memprediksi konsentrasi dari bahan kimia yang tersisa pada waktu yang diberikan selama proses bioremediasi ex-situ dan in-situ. Percobaan ini bertujuan untuk menentukan nilai kinetika biodegradasi untuk melihat efektivitas bakteri dalam proses remediasi tanah. Metode yang digunakan dalam percobaan ini adalah metode tidak langsung melalui pengukuran tingkat kekeruhan (turbiditas). Percobaan menggunakan bakteri Bacillus sp. sebagai bakteri pendegradasi oli, sedangkan konsentrasi oli yang digunakan berbeda-beda, yaitu 1,5%, 3%, dan 5%. Kurva hasil percobaan menunjukkan bahwa jumlah bakteri selalu berubah. Grafik hasil percobaan menunjukkan bahwa jumlah bakteri terbanyak terdapat dalam konsentrasi oli 4,5%. Sedangkan jumlah bakteri paling sedikit berada pada konsentrasi oli 1,5%. Melalui persamaan Monod, dapat diperoleh rata-rata laju pertumbuhan bakteri pada percobaan, yaitu 0,16133/menit. Laju pertumbuhan bakteri tercepat berada pada konsentrasi oli 3% yaitu 0,3131/menit, sedangkan laju pertumbuhan paling lambat berada pada konsentrasi oli 4,5% yaitu 0,0529/menit.
Kata kunci : Bacillus sp., Biodegradasi, Monod, Turbiditas

- by Muhammad Nofal
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- Engineering, Environmental Engineering, Environmental Remediation, Bioremediation

Th e greatest challenge in the 21st century is to provide new innovative water treatment methods. Th e conventional treatment processes are becoming incompetent by demands of space, energy, and economy and environment sustainability. Th e current, rapidly growing considerations have given room for sustainable alternative approaches of being greener, cheaper and energy effi cient. Amongst various biological methods to treat municipal wastewater like lagoons, aerobic oxidation ponds, anaerobic treatment chambers, dissolved air fl oatation and others, recently algal-based treatments are being most explored because of its viability for enhancement of treatment effi ciency and also advantage of added-value products. Th is chapter elaborates the sustainable algal-based approaches for energy-effi cient municipal wastewater treatment. Th e natural algal consortia dynamics gives a smart mode of enhancing the nutrient recovery and growth of algal biomass, hence a profi cient wastewater treatment. Th e chapter explores on the unknown potentials of the algae for energy-effi cient wastewater treatment. Th e algal consortia treating the wastewater have innate ability of biofl occulation, which exacerbates the

- by Kiruba Daniel and +1
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- Environmental Remediation, Water and wastewater treatment, Water Treatment, Algae

The contamination of groundwater by heavy metal, originating either from natural soil sources or from anthropogenic sources is a matter of utmost concern to the public health. Remediation of contaminated groundwater is of highest priority since billions of people all over the world use it for drinking purpose. In this paper, thirty five approaches for groundwater treatment have been reviewed and classified under three large categories viz chemical, biochemical/biological/biosorption and physico-chemical treatment processes. Comparison tables have been provided at the end of each process for a better understanding of each category. Selection of a suitable technology for contamination remediation at a particular site is one of the most challenging job due to extremely complex soil chemistry and aquifer characteristics and no thumb-rule can be suggested regarding this issue. In the past decade, iron based technologies, microbial remediation, biological sulphate reduction and various adsorbents played versatile and efficient remediation roles. Keeping the sustainability issues and environmental ethics in mind, the technologies encompassing natural chemistry, bioremediation and biosorption are recommended to be adopted in appropriate cases. In many places, two or more techniques can work synergistically for better results. Processes such as chelate extraction and chemical soil washings are advisable only for recovery of valuable metals in highly contaminated industrial sites depending on economical feasibility.► A number of groundwater treatment technologies for heavy metal remediation have been reviewed. ► Iron based techniques, Biological Sulphate Reduction and Permeable Reactive Barriers were most successful in the past decade. ► Biosorption is the emerging field mostly experimented in laboratories. ► More than one techniques can be coupled for site specific problems for better performance.

Crude oil pollution of water bodies is a worldwide problem that affects water ecosystems and is detrimental to human health and the diversity of living organisms. The objective of this study was to assess the ability of water hyacinth (Eichhornia crassipes (Mart.) Solms) combined with the presence of magnetic nanoparticles capped with natural products based on Myrrh to treat fresh water contaminated by crude petroleum oil. Magnetic nanoparticles based on magnetite capped with Myrrh extracts were prepared, characterized, and used to adsorb heavy components of the crude oil. The hydrophobic hexane and ether Myrrh extracts were isolated and used as capping for magnetite nanoparticles. The chemical structures, morphologies, particle sizes, and magnetic characteristics of the magnetic nanoparticles were investigated. The adsorption efficiencies of the magnetic nanoparticles show a greater efficiency to adsorb more than 95% of the heavy crude oil components. Offsets of Water hyacinth were...

- by Ahmad K Hegazy
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- Environmental Remediation, Nanomaterials, Nanoparticles, Oil Spill