Journal articles: 'Slurry Pond'

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Medvedieva, Olha, Yevhen Lapshyn, Natalia Koval, Abdikarim Zeynullin, and Olena Gupalo. "The resource-saving technology to restore the accumulation ability of tailing ponds." E3S Web of Conferences 168 (2020): 00054. http://dx.doi.org/10.1051/e3sconf/202016800054.

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The accumulating capacity of tailing ponds by technology infusion of pulp preliminary clarification in the alluvium charts with its subsequent thickening and storage in the form of a highly concentrated pulp at the bottom of the pond is proposed by authors in the work. For the first time, the time dependence of filling a temporary pond on the ratio of the initial and condensed slurry concentrations for such technologies is obtained. The formula for calculating the degree of condensation is proposed. It provides the parameters selection and justification of equipment for removing water from a temporary pond as the map is filled with the accumulating capacity restoration of tailing ponds. The calculation results for the proposed dependencies allow us to establish: the necessary values of the thickening degree of the hydromixture, the possible intervals of the change in the pulp flow before and after thickening, as well as the volume of water taken from the temporary pond, depending on the concentration of the slurry entering the pond from the alluvium maps, its volumetric flow rate , geometric parameters of the technology for waste storage and the operation duration of a temporary pond.

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Ridho, Muhammad, and Peter Eka Rosadi. "Penanganan Kolam Sedimentasi Hasil Pencucian Bauksit Di PT. ANTAM Tbk. Tayan." Jurnal Mineral, Energi dan Lingkungan 2, no. 2 (February 11, 2019): 87. http://dx.doi.org/10.31315/jmel.v2i2.2157.

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Bauxite ore mining PT.Antam Tbk. located in Tayan Hilir Subdistrict, Sanggau Regency, West Kalimantan Province is an open pit backfilling system. Besides the bauxite ore extraction, the washing process resulted slurry which is entering the open channel towards the sedimentation pond. This study aims to determine the total discharge of slurry that will enter the sedimentation pond and assess the capacity of existing sedimentation ponds. The results showed that based on the production target of 700,000 tons of Bauxite Washed/year with 60% concretion factor data, the total discharge of water entering the sedimentation pond was 3.54 m3/sec. The slurry from the open channel will go into the sedimentation pond so that the deposition found in Segment I, IV, V, and VI was 409.06 m3/day, 254.59 m3/day, 561.35 m3/day, and 273.90 m3/day respectivelly. Intensive dredging material will be carried out using two Hitachi Zaxis 210 LC Long-Arm Excavator units. The cleaning time needed by Segment I, IV, V, and VI are 10 days, 6 days, 9 days and 5 days, so that the dredging time of Segment I, IV, V, and VI are 82 days, 65 days, 53 days and 62 days respectivelly

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3

Chase, Alisia G. "Toxic Slurry and Pond Scum." Afterimage 36, no. 2 (September 1, 2008): 27–28. http://dx.doi.org/10.1525/aft.2008.36.2.27.

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Kopp, Radovan, Jan Mareš, Andrea Ziková, and Tomáš Vítek. "Variations of physical and chemical parameters in hypertrophic pond within pig slurry application." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 56, no. 2 (2008): 95–100. http://dx.doi.org/10.11118/actaun200856020095.

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During the years 2001 and 2002 we conducted hydrochemical monitoring of intensively managed pond to evaluate the impact of high pig slurry doses on eutrophication. Pig slurry application was carried out in colder period of the year (February–April) via tube system with sludge pump from nearby piggery. Our results showed that pig slurry application do not permanently affect the water quality of Jarohněvický pond. When the correct application is made slurry is effectively utilized by biomass for the growth, which prevents surface and underground waters to be polluted as in the case of incorrect application on agricultural land.Critical point of this technology in terms of water management is the way of pig slurry application and the exact dose. Even extremely high slurry doses (16.1 kg . m−2 in 2001 and 15.6 kg . m−2 in 2002) used in Jarohněvický pond did not negatively affected pond ecosystem. Only higher amount of organisms that increased natural fish production was recorded. It is necessary to implement this ameliorative intervention in colder period of the year considering higher hazard of variations in decisive hydrochemical parameters at higher water temperature.

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5

Chu, J., M. W. Bo, and A. Arulrajah. "Reclamation of a slurry pond in Singapore." Proceedings of the Institution of Civil Engineers - Geotechnical Engineering 162, no. 1 (February 2009): 13–20. http://dx.doi.org/10.1680/geng.2009.162.1.13.

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6

Qu, Yanpeng, Cheng Zhou, Yunpan Zhong, Songying Chen, and Ruiyan Wang. "A computational study on gas–liquid flow in a lime slurry pond equipped with a rotary jet mixing system." Advances in Mechanical Engineering 9, no. 2 (February 2017): 168781401769046. http://dx.doi.org/10.1177/1687814017690468.

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The flue-gas desulfurization model was studied through computational fluid dynamics software. The oxidation air was asymmetrically pumped into the slurry pond. A rotary jet mixing system was established at the bottom center of the pond to agitate the lime slurry. The Navier–Stokes equation as the control equation, the standard k–ε turbulence model, sliding grids structure, and three-dimensional Eulerian multiphase flow of lime slurry were used for the numerical simulation. The independence of the meshes and the time step was verified. The distribution of the concentration of oxidation air and influents on the velocity of flow was analyzed with five angular velocities (0.01, 0.10, 0.20, 0.50, and 1 rad/s) for the rotary jet mixing. The simulation results showed that the angular velocity has a great influence on the velocity of the slurry and the distribution of the oxidation air.

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Tao, D., B. Li, S. Johnson, and B. K. Parekh. "A flotation study of refuse pond coal slurry." Fuel Processing Technology 76, no. 3 (June 2002): 201–10. http://dx.doi.org/10.1016/s0378-3820(02)00025-5.

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8

Terrero, Martire Angélica, María Ángeles Muñoz, Ángel Faz, María Dolores Gómez-López, and Jose A. Acosta. "Efficiency of an Integrated Purification System for Pig Slurry Treatment under Mediterranean Climate." Agronomy 10, no. 2 (February 2, 2020): 208. http://dx.doi.org/10.3390/agronomy10020208.

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The intensification of pig production is considered a risky activity for the environment when the generated pig slurry is not adequately treated. In addition, intensive agriculture practices where pig slurry is applied to the cropland could cause nitrate leaching, salinization, and soil pollution (heavy metals and pathogens), thus the development of an eco-friendly system for pig slurry treatment is essential to avoid undesirable environmental impacts. The main objective of this study was to assess the efficiency of an integrated purification system (IPS) for treating pig slurry. The system included a pretreatment module (raw pig slurry tank, phase separator, aeration tank, and settlement tank), constructed wetlands (CWs) that included an unplanted cell and a planted cell, and a storage pond (SP). Pig slurry samples from the pretreatment modules, CWs, and SP were collected in triplicate and physic-chemical and microbial analyses were performed. Results showed that the pretreatment modules decreased the total suspended solids (TSS), total nitrogen (TN), and total phosphorus (TP) concentrations in the liquid fraction. Higher total nitrogen removal was reported in the planted cell, which decreased from 4.0 g L−1 to 1.9 g L−1 in the inflow and outflow, respectively. Total efficiencies over 85% were found in the planted and unplanted cells for TSS, Kjeldahl nitrogen (KN), chemical oxygen demand (COD), and TP. Microbial parameters were eliminated after the treatment in the planted cell. Therefore, the results indicated that filtration (pretreatment), purification (constructed wetland), and bioremediation (storage pond) constituted an appropriate IPS for treating pig slurry.

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9

Wyness, P., J. F. Klausner, D. Y. Goswami, and K. S. Schanze. "Performance of Nonconcentrating Solar Photocatalytic Oxidation Reactors: Part II—Shallow Pond Configuration." Journal of Solar Energy Engineering 116, no. 1 (February 1, 1994): 8–13. http://dx.doi.org/10.1115/1.2930069.

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A solar photocatalytic oxidation facility has been fabricated in which the destruction of 4-chlorophenol (4CP) is tested in three adjacent shallow pond reactors. Each of the reactors has depths of 5.1, 10.2, and 15.3 cm (2, 4, and 6 in.), respectively. It is found that 4CP is successfully oxidized with the photocatalyst, titanium dioxide (TiO2), suspended in a slurry or adhered to a fiberglass mesh. The pond reactors, however, perform better with the slurry. It has also been found that the first-order rate constant for oxidation of 4CP increases with decreasing initial concentration. For the same incident ultraviolet (UV) intensity, catalyst loading, and initial solute concentration, the oxidation rate of 4CP is invariant provided the aperture to volume ratio is fixed. It has been determined that the 4CP solution contains sufficient dissolved oxygen to support the photocatalytic oxidation process. Direct evidence is provided to demonstrate that the utilization of photons in the photocatalytic process becomes less efficient as the number of incident photons on the catalyst increases.

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10

Huchunayev, Buzgigit M., Oksana O. Dakhova, Svetlana A. Bekkiyeva, and Svetlana B. Hatefova. "Impact of the Slurry Pond of the Tyrnyauz Tungsten-Molybdenum Complex on the Mountain Territories Environment." Materials Science Forum 931 (September 2018): 1070–75. http://dx.doi.org/10.4028/www.scientific.net/msf.931.1070.

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The results of the Tyrnyauz tungsten-molybdenum Plant (TTMP) slurry pond settler environment impacts assessment are given in this scientific work, and the recommendations about the negative impact reduction on the environment are made. In the given work the characteristics of the environment state are investigated: atmospheric air, water objects and land resources.

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11

Wang, Kun, Peng Yang, Karen Hudson-Edwards, Wensheng Lyu, Chao Yang, and Xiaofei Jing. "Integration of DSM and SPH to Model Tailings Dam Failure Run-Out Slurry Routing Across 3D Real Terrain." Water 10, no. 8 (August 16, 2018): 1087. http://dx.doi.org/10.3390/w10081087.

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Tailings dam failure accidents occur frequently, causing substantial damage and loss of human and animal life. The prediction of run-out tailings slurry routing following dam failures is of great significance for disaster prevention and mitigation. Using satellite remote sensing digital surface model (DSM) data, tailings pond parameters and the advanced meshless smoothed particle hydrodynamics (SPH) method, a 3D real-scale numerical modelling method was adopted to study the run-out tailings slurry routing across real downstream terrains that have and have not been affected by dam failures. Three case studies, including a physical modelling experiment, the 2015 Brazil Fundão tailings dam failure accident and an operating high-risk tailings pond in China, were carried out. The physical modelling experiment and the known consequences were successfully modeled and validated using the SPH method. This and the other experiments showed that the run-out tailings slurry would be tremendously destructive in the early stages of dam failure, and emergency response time would be extremely short if the dam collapses at its full designed capacity. The results could provide evidence for disaster prevention and mitigation engineering, emergency management plan optimization, and the development of more responsible site plans and sustainable site designs. However, improvements such as rheological model selection, terrain data quality, computing efficiency and land surface roughness need to be made for future studies. SPH numerical modelling is a powerful and advanced technique that is recommended for hazard assessment and the sustainable design of tailings dam facilities globally.

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12

Sahoo, Saroj Kumar, and Nikkam Suresh. "Recovery of coal values from the refuse pond coal slurry using flotation." Energy Sources, Part A: Recovery, Utilization, and Environmental Effects 40, no. 10 (May 19, 2018): 1250–56. http://dx.doi.org/10.1080/15567036.2018.1476620.

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13

Onyla, C. O., A. M. Uyub, J. C. Akunna, N. A. Norulaini, and A. K. M. Omar. "Increasing the fertilizer value of palm oil mill sludge: bioaugmentation in nitrification." Water Science and Technology 44, no. 10 (November 1, 2001): 157–62. http://dx.doi.org/10.2166/wst.2001.0608.

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Malaysia is essentially an agricultural country and her major polluting effluents have been from agro-based industries of which palm oil and rubber industries together contribute about 80% of the industrial pollution. Palm oil sludge, commonly referred to, as palm oil mill effluent (POME) is brown slurry composed of 4-5% solids, mainly organic, 0.5-1% residual oil, and about 95% water. The effluent also contains high concentrations of organic nitrogen. The technique for the treatment of POME is basically biological, consisting of pond systems, where the organic nitrogen is converted to ammonia, which is subsequently transformed to nitrate, in a process called nitrification. A 15-month monitoring program of a pond system (combined anaerobic, facultative, and aerobic ponds in series) confirmed studies by other authors and POME operators that nitrification in a pond system demands relatively long hydraulic retention time (HRT), which is not easily achieved, due to high production capacity of most factories. Bioaugmentation of POME with mixed culture of nitrifiers (ammonia and nitrite oxidizers) has been identified as an effective tool not only for enhancing nitrification of POME but also for improving quality of POME as source of liquid nitrogen fertilizer for use in the agricultural sector, especially in oil palm plantations. Nitrate is readily absorbable by most plants, although some plants are able to absorb nitrogen in the form of ammoniun. In this study, up to 60% reduction in HRT (or up to 20% reduction in potential land requirement) was achieved when bioaugmentation of POME was carried out with the aim of achieving full nitrification.

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14

Suthaker, Nagula N., and J. Don Scott. "Measurement of hydraulic conductivity in oil sand tailings slurries." Canadian Geotechnical Journal 33, no. 4 (August 20, 1996): 642–53. http://dx.doi.org/10.1139/t96-089-310.

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Fine tails, the resulting fine waste from oil sand processing, undergoes large-strain consolidation in tailings ponds. Its consolidation behaviour must be analyzed using a large-strain consolidation theory, which requires the determination of the relationship between the void ratio and hydraulic conductivity. Conventional measurement techniques are not suitable for fine tails, and a special slurry consolidometer, with a clamping device to prevent seepage-induced consolidation, was designed to determine the hydraulic conductivity of the fine tails and nonsegregating fine tails sand slurries. The hydraulic conductivity of slurries is not constant but decreases with time to a steady-state value. Hydraulic conductivity is also influenced by the hydraulic gradient and bitumen content. It is shown that a low hydraulic gradient, less than 0.2, is necessary to counteract the effect of the bitumen and to represent tailings pond conditions. The hydraulic conductivity of fine tails sand mixes is controlled by the fines void ratio, hence, fines content. The hydraulic conductivity of chemically amended nonsegregating tailings can be lower than that of fine tails. However, acidlime or acid fly ash amended nonsegregating tailings have similar hydraulic conductivity values in terms of fines void ratio. The hydraulic conductivity of nonsegregating tailings appears to be governed by fines content and by the nature of the fines aggregation caused by the chemical additive. Key words: tailings, slurries, hydraulic conductivity, slurry consolidometer, nonsegregating tailings, oil sands.

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15

Ginting, Nurzainah. "Utilization of Blood Meal, Slaughterhouse Waste and Bio Gas Slurry into Fertilizer." Indonesian Journal of Agricultural Research 3, no. 2 (July 19, 2020): 105–15. http://dx.doi.org/10.32734/injar.v3i2.4267.

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In slaughterhouses the burden of waste such as excessive blood volume causes waste process with sewage treatment pond can not work optimally. Blood should be separated and processed into other products. This study aims to prove that blood processing from slaughterhouse produces higher quality organic fertilizer. In this research, the fermentor used in the composting process is biogas slurry. The study used RAL (Complete Randomized Design) with 4 treatments; P0 = without blood meal, P1 = blood meal 6.5%, P2 = blood meal 13% and P3 = blood meal 19.5%. There is no difference between the treatment at fertilizer temperature, pH and C / N. In the treatment application of blood meal by 19.5% in the fourth week of C / N was 12.17 as a requirement for mature fertilizer. The treatment by adding 375 g blood meal on 6 kg livestock feces and 6 kg feed leftover while use biogas slurry as the fermentor was a novel organic fertilizer formula.

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16

Peu, Pascal, Hubert Brugï¿½re, Anne-Marie Pourcher, Monique Kï¿½rourï¿½dan, Jean-Jacques Godon, Jean-Philippe Delgenï¿½s, and Patrick Dabert. "Dynamics of a Pig Slurry Microbial Community during Anaerobic Storage and Management." Applied and Environmental Microbiology 72, no. 5 (May 2006): 3578–85. http://dx.doi.org/10.1128/aem.72.5.3578-3585.2006.

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ABSTRACT The microbial community of a pig slurry on a farm was monitored for 6 months using both molecular and cultural approaches. Sampling was carried out at all the different stages of effluent handling, from the rearing build-up to slurry spreading. Total DNA of each sample was extracted and analyzed by PCR-single-strand conformation polymorphism (SSCP) analysis using primers targeting the 16S rRNA genes from the archaeal and bacterial domains and also the Eubacterium-Clostridium, Bacillus-Streptococcus-Lactobacillus, and Bacteroides-Prevotella groups. A comparison of the SSCP profiles showed that there were rapid changes in the dominant bacterial community during the first 2 weeks of anaerobic storage and that the community was relatively stable thereafter. Several bacterial populations, identified as populations closely related to uncultured Clostridium and Porphyromonas and to Lactobacillus and Streptococcus cultured species commonly isolated from pig feces, remained present and dominant from the rearing build-up to the time of spreading. Enumeration of fecal indicators (enterococci and Escherichia coli) performed in parallel using cultural methods revealed the same trends. On the other hand, the archaeal community adapted slowly during pig slurry storage, and its diversity increased. A shift between two hydrogenotrophic methanogenic Methanobrevibacter populations from the storage pit to the pond was observed. Microorganisms present in pig slurry at the time of spreading could not be detected in soil after spreading by either molecular or cultural techniques, probably because of the detection limit inherent in the two techniques.

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Vinikour, W. S., K. E. LaGory, and E. D. Pentecost. "Fate of an Artificial Pond Receiving Drainage From a Reclaimed Coal Refuse and Slurry Area." Journal American Society of Mining and Reclamation 1988, no. 2 (1988): 167–72. http://dx.doi.org/10.21000/jasmr88020167.

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18

Taylor, J., and B. A. Middleton. "Comparison of litter decomposition in a natural versus coal-slurry pond reclaimed as a wetland." Land Degradation & Development 15, no. 4 (July 2004): 439–46. http://dx.doi.org/10.1002/ldr.625.

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19

Toor, Amrit Pal, Anoop Verma, C. K. Jotshi, P. K. Bajpai, and Vasundhara Singh. "Photocatalytic degradation of Direct Yellow 12 dye using UV/TiO2 in a shallow pond slurry reactor." Dyes and Pigments 68, no. 1 (January 2006): 53–60. http://dx.doi.org/10.1016/j.dyepig.2004.12.009.

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20

Martinez-Pagan, P., A. F. Cano, G. R. Ramos da Silva, and A. B. Olivares. "2-D Electrical Resistivity Imaging to Assess Slurry Pond Subsoil Pollution in the Southeastern Region of Murcia, Spain." Journal of Environmental & Engineering Geophysics 15, no. 1 (March 1, 2010): 29–47. http://dx.doi.org/10.2113/jeeg15.1.29.

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21

Solomon, Shola Gabriel, Gabriel Arome Ataguba, and Gabriel Enemona Itodo. "Performance ofClarias gariepinusFed Dried Brewer’s Yeast(Saccharomyces cerevisiae)Slurry in Replacement for Soybean Meal." Journal of Nutrition and Metabolism 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/8936060.

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Following disparity of earlier results, this study tested the performance of African catfishClarias gariepinusfed dried brewer’s yeast slurry meal (DBYM) based diets. Fingerlings ofC. gariepinuswith pooled mean initial weight of1.58±0.01 g were stocked in hapas (1 m × 1 m × 1 m) immersed in an earthen pond at a density of 15 fish per cage. Five diets with increasing substitution of soybean meal with 25%, 50%, 75%, and 100% of dried brewer’s yeast and a control without dried brewer’s yeast (0% substitution) were evaluated for 8 weeks. Palatability of diets reduced with increasing levels of DBYM. Growth and utilization parameters such as weight gain, feed conversion ratio, protein efficiency ratio, and specific growth rate differed significantly (p<0.05) among treated groups. Specific growth rate decreased with increasing substitution while the best feed conversion ratio was obtained in the diet devoid of DBYM. Protein efficiency and utilization decreased with increasing levels of DBYM. Body composition was also affected by inclusion of DBYM with significant differences (p<0.05) being observed across the diets. The trend in body composition follows the utilization of the diets. We conclude that the optimal range of inclusion and substitution of soybean meal with DBYM inC. gariepinusfeed is between 1% and 14% of dry matter.

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22

Fayziev, Khamidkhon, Takhirjon Sultanov, and Elyor Toshmatov. "Methods for calculating the balance during the period of draw-off, drainage of sludge collector cells and construction of secondary embankment dams." E3S Web of Conferences 264 (2021): 03048. http://dx.doi.org/10.1051/e3sconf/202126403048.

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An industrial waste-phosphogypsum-is formed in the production of phosphorus mineral fertilizers. As is well-known, the issues of processing and utilization of phosphogypsum on an industrial scale remain unsolved. Consequently, production waste generated at chemical plants is stored in various types of storage tanks. The currently used hydraulic storage method provides for the supply of waste in the form of a slurry into the hydraulic dump cells, their sequential dehydration in the dump, and the subsequent development of a part of the stored waste for the construction of secondary dams. However, due to the low water-release properties of phosphogypsum, it is impossible to ensure its dehydration to the required degree, in large volumes, and the required period. Therefore, various designs of watertight diaphragms and drainage devices are provided in the sludge collector to accelerate the process of dehydration of the phosphogypsum strata. The balance of the sludge collector should be assessed in two periods: the initial period when the sludge collector cells are filled, bounded by the primary dam, and the subsequent period when the reservoir is built up by erecting secondary dams from the stored material. In the initial period, the operating mode of the sludge collector is divided into two stages: in the first stage, a pond is formed above the layer of sludge with a certain predetermined depth; in the second stage, this depth of water in the pond is kept constant by the spillways. The second build-up period is preceded by a period of cell preparation, namely: the draw-off of the pond and drainage of the cell to a moisture content suitable for the dam filling and normal operation of the mechanisms used in the construction of dams. This article presents the results of filtration studies in sludge collectors with an impermeable screen (made of polymer film, asphalt-polymer concrete, etc.) above the screen drainage system. The calculating methods for the determination of filtration parameters in the second period of operation are described: when the pulp supply stops, and a pond of clarified water with a depth of H0 is drawn off.

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Ghrair, Ayoup M., Andrew Heath, Kevin Paine, and Muath Al Kronz. "Waste Wash-Water Recycling in Ready Mix Concrete Plants." Environments 7, no. 12 (December 11, 2020): 108. http://dx.doi.org/10.3390/environments7120108.

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The management of waste wash-water (WWW) is one of the most significant environmental problems associated with ready-mix concrete production worldwide. The problems are exacerbated should it be disposed of in an inappropriate manner. This study evaluated the potential of WWW recycling in ready mix concrete plants in Jordan. A representative waste wash-water sample (400 L) was collected from a basin in a ready-mix concrete company. A pilot plant on the lab scale was fabricated and installed. The treatment system consisted of a concrete washout reclaimer, wedgebed slurry settling pond, slow sand filtration unit, and a neutralization unit. Water samples were collected from all stages of the pilot plant and analyzed. The collected waste wash-water samples were utilized for replacement of well water (mixing water) at various ratios. Fourteen concrete mixtures were produced and cast, as well as tested at various curing ages (7, 28, and 90 days). The results show that the raw WWW was not acceptable as mixing water even after dilution as it led to significant reductions in concrete compressive strength and low workability. However, the WWW from the settling pond, the filtered WWW and the filtered-neutralized WWW at dilution ratios up to 75% were shown to be potential alternatives to fresh water for ready-mixed concrete. Therefore, the current guidelines for mixing water quality should be revised to encourage the reuse of the WWW.

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Kabas, S., A. Faz, J. A. Acosta, R. Zornoza, S. Martínez-Martínez, D. M. Carmona, and J. Bech. "Effect of marble waste and pig slurry on the growth of native vegetation and heavy metal mobility in a mine tailing pond." Journal of Geochemical Exploration 123 (December 2012): 69–76. http://dx.doi.org/10.1016/j.gexplo.2012.07.008.

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Cheng, Haiyong, Jin Liu, Shunchuan Wu, and Xiaoqiang Zhang. "Fluidization Analysis of Thickening in the Deep Cone for Cemented Paste Backfill." Advances in Materials Science and Engineering 2020 (August 5, 2020): 1–7. http://dx.doi.org/10.1155/2020/6285981.

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Cemented paste backfill (CPB) can effectively eliminate the risk of dam break in goaf and tailings pond which used tailings waste. Deep cone thickener (DCT) is an efficient machine for the system of paste preparation, and the concentration of slurry at the bottom is high and distributed unevenly, which will cause too much partial resistance and failure of thickener. Focusing on the above problems, fluidization design was conducted by using the fluidization theory. The delivery law of flocs was analyzed, and the isobaric surface was obtained. The equation of pressure and critical velocity of the ideal fluidized bed was acquired by analyzing the relationship between pressure and critical velocity. Based on the characteristics of tailings and distribution of the bonding zone, the arrangement, number, and working mode of spray nozzles were reformed. It is verified that the failure time of thickener decreased from 14 hours to 1 hour and the range of concentration increased from 74%∼78% to 78%∼80%, which improved the stability and reliability of DCT. The depth thickening mechanism is obtained, and the thickening method has been improved which provides a theoretical basis for the effective preparation of paste.

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Caughill, D. L., N. R. Morgenstern, and J. D. Scott. "Geotechnics of nonsegregating oil sand tailings." Canadian Geotechnical Journal 30, no. 5 (October 1, 1993): 801–11. http://dx.doi.org/10.1139/t93-071.

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The present method of oil sands tailings disposal results in a tailings pond with a fine tailings zone that will take many decades to consolidate fully. The fine tailings accumulate as a result of the segregating characteristics of the tailings stream. Nonsegregating mixes of total tailings are desirable to prevent or greatly reduce the formation of a fine tailings zone. This study investigated the use of lime and sulphuric acid to prevent segregation of the tailings stream. Two batches of Syncrude tailings were tested. These averaged 48 and 55% solids and 17% fines (< 44 μm). The hindered settling and consolidation properties of nonsegregating mixes were determined using large-diameter standpipe and slurry consolidation cells. Nonsegregating mixes were achieved by adding 600–800 ppm CaO, based on total weight, or 7.5–10 mL/L of 10% H2SO4, based on the total volume of tailings. Predictions of field performance using a finite strain consolidation program indicate that a deposition rate of up to 20 m/year of treated total tailings is possible, depending upon the simultaneous degree of consolidation desired. The discovery of nonsegregating mixes with sufficient self-draining capability opens many options to address this important waste-management problem. Key words : oil sand tailings, nonsegregating, hindered settling, consolidation, permeability, laboratory.

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Visscher, Pieter T., Rachel F. Gritzer, and Edward R. Leadbetter. "Low-Molecular-Weight Sulfonates, a Major Substrate for Sulfate Reducers in Marine Microbial Mats." Applied and Environmental Microbiology 65, no. 8 (August 1, 1999): 3272–78. http://dx.doi.org/10.1128/aem.65.8.3272-3278.1999.

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ABSTRACT Several low-molecular-weight sulfonates were added to microbial mat slurries to investigate their effects on sulfate reduction. Instantaneous production of sulfide occurred after taurine and cysteate were added to all of the microbial mats tested. The rates of production in the presence of taurine and cysteate were 35 and 24 μM HS− h−1 in a stromatolite mat, 38 and 36 μM HS− h−1 in a salt pond mat, and 27 and 18 μM HS− h−1 in a salt marsh mat, respectively. The traditionally used substrates lactate and acetate stimulated the rate of sulfide production 3 to 10 times more than taurine and cysteate stimulated the rate of sulfide production in all mats, but when ethanol, glycolate, and glutamate were added to stromatolite mat slurries, the resulting increases were similar to the increases observed with taurine and cysteate. Isethionate, sulfosuccinate, and sulfobenzoate were tested only with the stromatolite mat slurry, and these compounds had much smaller effects on sulfide production. Addition of molybdate resulted in a greater inhibitory effect on acetate and lactate utilization than on sulfonate use, suggesting that different metabolic pathways were involved. In all of the mats tested taurine and cysteate were present in the pore water at nanomolar to micromolar concentrations. An enrichment culture from the stromatolite mat was obtained on cysteate in a medium lacking sulfate and incubated anaerobically. The rate of cysteate consumption by this enrichment culture was 1.6 pmol cell−1h−1. Compared to the results of slurry studies, this rate suggests that organisms with properties similar to the properties of this enrichment culture are a major constituent of the sulfidogenic population. In addition, taurine was consumed at some of highest dilutions obtained from most-probable-number enrichment cultures obtained from stromatolite samples. Based on our comparison of the sulfide production rates found in various mats, low-molecular-weight sulfonates are important sources of C and S in these ecosystems.

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Jing, Xiaofei, Yulong Chen, Dan Xie, David J. Williams, Shangwei Wu, Wensong Wang, and Tianwei Yin. "The Effect of Grain Size on the Hydrodynamics of Mudflow Surge from a Tailings Dam-Break." Applied Sciences 9, no. 12 (June 18, 2019): 2474. http://dx.doi.org/10.3390/app9122474.

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Due to the differences in mineral processing techniques, the grain-size of tailings used in the construction of a tailings pond is not commensurate. It has been determined that the hydrodynamic characteristics of mudflow resulting from the failure of tailings dams are directly influenced by grain-size, solids concentration, and the surface roughness of gully and impoundment geometry. However, the behavior and influence of the grain size of mudflow resulting from a tailings dam failure have not been sufficiently examined. To investigate the effect of grain size on the hydrodynamic characteristics of mudflow surging from tailings dam failure, the law of mudflow evolution, the change of dynamics pressure, and the velocity distributions of mudflow have been obtained via a series of flume experiments utilizing three types of grain size tailings (d50 = 0.72 mm; d50 = 0.26 mm; d50 = 0.08 mm, respectively). This study proves conclusively that with an increase in grain size, the peak value of mudflow depth notably decreases in the same section. Furthermore, it has been noted that both the velocity and the dynamic pressure raise significantly, wherein the velocity displays two distinct primary stages; namely a rapid reduction stage and a slow reduction stage. This research provides a framework for the exploration of the effect of grain size on the hydrodynamics of slurry surging from a tailings dam failure, and all presented results provide an indispensable tool in terms of the accurate assessment of potential damage in the case of a prospective impoundment failure.

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Lomans, B. P., A. Pol, and H. J. M. Op den Camp. "Microbial cycling of volatile organic sulfur compounds in anoxic environments." Water Science and Technology 45, no. 10 (May 1, 2002): 55–60. http://dx.doi.org/10.2166/wst.2002.0288.

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Microbial cycling of volatile organic sulfur compounds (VOSC) is investigated due to the impact these compounds are thought to have on environmental processes like global temperature control, acid precipitation and the global sulfur cycle. Moreover, in several kinds of industries like composting plants and the paper industry VOSC are released causing odor problems. Waste streams containing these compounds must be treated in order to avoid the release of these compounds to the atmosphere. This paper describes the general mechanisms for the production and degradation of methanethiol (MT) and dimethyl sulfide (DMS), two ubiquitous VOSC in anaerobic environments. Slurry incubations indicated that methylation of sulfide and MT resulting in MT and DMS, respectively, is one of the major mechanisms for VOSC in sulfide-rich anaerobic environments. An anaerobic bacterium that is responsible for the formation of MT and DMS through the anaerobic methylation of H2S and MT was isolated from a freshwater pond after enrichment with syringate as a methyl group donating compound and sole carbon source. In spite of the continuous formation of MT and DMS, steady state concentrations are generally very low. This is due to the microbial degradation of these compounds. Experiments with sulfate-rich and sulfate-amended sediment slurries demonstrated that besides methanogens, sulfate-reducing bacteria can also degrade MT and DMS, provided that sulfate is available. A methanogen was isolated that is able to grow on DMS as the sole carbon source. A large survey of sediments slurries of various origin demonstrated that both isolates are commonly occurring inhabitants of anaerobic environments.

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Svoboda, I. F., and H. J. Fallowfield. "An Aerobic Piggery Slurry Treatment System with Integrated Heat Recovery and High-Rate Algal Ponds." Water Science and Technology 21, no. 4-5 (April 1, 1989): 277–87. http://dx.doi.org/10.2166/wst.1989.0230.

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A piggery with an integrated slurry removal and treatment system with heat recovery and two algal raceways for a secondary treatment of settled treated slurry has been built. Piggery slurry from about 250 fattening pigs and 100 weaners has been aerobically treated in a continuous culture reactor at 36°C. Metabolic heat and heat from the aerator after upgrading by a heat pump was utilized for space heating in a weaner house and in one of the algal raceways. Intermittent heating had little effect upon algal productivity and effluent treatment since the system was essentially light limited. Characteristics of treated slurry and quantity of heat evolved are in good agreement with predicted values by a mathematical model.

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Sehgal, Harjeet S., Kamaldeep Kaur, and Gurpreet K. Sehgal. "Phytoplankton response to biogas slurry in carp ponds." Bioresource Technology 37, no. 3 (January 1991): 229–34. http://dx.doi.org/10.1016/0960-8524(91)90188-p.

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Sehgal, Harjeet S., Kamaldeep Kaur, and Gurpreet K. Sehgal. "Zooplankton response to biogas slurry in carp ponds." Bioresource Technology 41, no. 2 (January 1992): 111–16. http://dx.doi.org/10.1016/0960-8524(92)90179-2.

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Singh, Kanwar Pal, Arvind Kumar, and Deo Raj Kaushal. "Pressure drop calculation for fly ash slurry using rheological model." World Journal of Engineering 16, no. 6 (December 2, 2019): 751–67. http://dx.doi.org/10.1108/wje-03-2019-0086.

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Purpose This paper aims to the transportation of high concentration slurry through pipelines that will require thorough understanding of physical and rheological properties of slurry, as well as its hydraulic flow behavior. In spite of several contributions by the previous researchers, there is still a need to enrich the current understanding of hydraulic conveying through pipeline at various flow parameters. The pilot plant loop tests, particularly at high concentrations, are tedious, time-consuming and complex in nature. Therefore, in the current research the prediction methodology for slurry pipeline design based on rheological model of the slurry is used for calculation of pressure drop and other design parameters. Design/methodology/approach It has been established that slurry rheology plays important role in the prediction of pressure drop for laminar and turbulent flow of commercial slurries through pipeline. In the current research fly ash slurry at high concentration is chosen for rheological analysis. The effect of particle size and solid concentration is experimentally tested over the rheological behavior of slurry and based on the rheological data a correlation is developed for calculation of pressure drop in slurry pipeline. Findings The present study strongly supports the analytical approach of pressure drop prediction based on the rheological parameters obtained from the bench scale tests. The rheological properties are strongly influenced by particle size distribution (PSD), shear rate and solid mass concentration of the slurry samples. Pressure drop along the pipeline is highly influenced by flow velocity and solid concentration. The presence of coarser particles in the slurry samples also leads to high pressure drop along the pipeline. As the concentration of solid increase the shear stress and shear viscosity increase cause higher pressure drop. Research limitations/implications The transportation of slurry in the pipeline is very complex as there are lot of factors that affect the flow behavior of slurry in pipelines. From the vast study of literature it is found that flow behavior of slurry changes with the change in parameters such as solids concentration, flow velocity, PSD, chemical additives and so on. Therefore, the accurate prediction of hydraulic parameter is very difficult. Different slurry samples behave differently depending upon their physical and rheological characteristics. So it is required to study each slurry samples individually that is time-consuming and costly. Practical implications Nowadays in the world, long distance slurry pipelines are used for the transportation of highly concentration slurries. Many researchers have carried out an experiment in the design aspects of hydraulic transportation system. Rheological characteristics of slurry also play crucial role in determining important parameters of hydraulic conveying such as head loss in commercial slurry pipeline. The current research is useful for the prediction of pressure drop based on rheological behavior of fly ash slurry at various solid concentrations. The current research is helpful for finding the effect of solid concentration and flow velocity on the flow behavior of slurry. Social implications Slurry pipeline transportation has advantages over rail and road transportation because of low energy consumption, economical, less maintenance and eco-friendly nature. Presently majority of the thermal power plants in India and other parts of the world dispose of coal ash at low concentration (20 per cent by weight) to ash ponds using the slurry pipeline. Transporting solids in slurry pipelines at higher concentrations will require a thorough knowledge of pressure drop. In the current research a rheological model is proposed for prediction of pressure drop in the slurry pipeline, which is useful for optimization of flow parameters. Originality/value All the experimental work is done on fly ash slurry samples collect from the Jharli thermal power plant from Haryana State of India. Bench scale tests are performed in the water resource laboratory of IIT Delhi for physical and rheological analysis of slurry. It has been shown in the results that up to solid concentration of 50 per cent by mass all the samples behave as non-Newtonian and follows a Herschel–Bulkley model with shear thickening behavior. In the present research all the result outcomes are unique and original and does not copied from anywhere.

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Mathis, Marilyn J., and Beth A. Middleton. "Simulated Herbivory and Vegetation Dynamics in Coal Slurry Ponds Reclaimed as Wetlands." Restoration Ecology 7, no. 4 (December 1999): 392–98. http://dx.doi.org/10.1046/j.1526-100x.1999.72034.x.

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Gaevaya, E. V., Ya E. Bogaychuk, S. S. Tarasova, and E. V. Zakharova. "POSSIBILITIES OF WASTE MANGEMENT WHILE FORMING SOIL-LIKE ENVIRONMENT." Oil and Gas Studies, no. 2 (May 1, 2017): 82–89. http://dx.doi.org/10.31660/0445-0108-2017-2-82-89.

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The research results on the recovery of drilled solids and spent drilling mud with the use of phosphogypsum in combination with the humicagent «Rostok» showed that the resulting soillike environment can be used while recultivating slurry ponds and disturbed lands. Adding extra 5-20 % of spent drilling mud didn’t affect the chemical composition of the soil significantly. Using the humicagent «Rostok» favorably impacts the development of plants, besides the formation of a viable phytocenosis takes place with the significant increase of phytomass of vegetative aerial shoots by 28-31 %.

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Das, Madhumita, Pralaya Ranjan Behera, and Biswajit Dash. "Periphyton communities in carp culture ponds treated with cow manure and biogas slurry." Aquatic Living Resources 30 (2017): 25. http://dx.doi.org/10.1051/alr/2017026.

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Middleton, Beth A. "Seed Banks and Species Richness Potential of Coal Slurry Ponds Reclaimed as Wetlands." Restoration Ecology 3, no. 4 (December 1995): 311–18. http://dx.doi.org/10.1111/j.1526-100x.1995.tb00099.x.

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Yogesh Mishra. "Climate change risks and mitigating measures of freshwater aquaculture in unmanaged ponds of Kaushambi district U.P." GSC Biological and Pharmaceutical Sciences 13, no. 2 (November 30, 2020): 253–59. http://dx.doi.org/10.30574/gscbps.2020.13.2.0385.

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The purpose of the study is to identify various climatic change risks encountered by fish farmers while doing freshwater aquaculture in the unmanaged ponds of district kaushambi Uttar Pradesh. The various climate change risks which were faced by rural farmers of Kaushambi are water quality, flooding of ponds, less rain, heavy mortality of fishes, planktonic collapse, long dry spells, disease outbreak, destruction of embankments etc. The study also includes the measures to encounter these risks. To maintain the quality of water the farmers have used lime, manure, alum, KMnO4, salt and exchange of water. To control the flooding of ponds the farmers raises embankments by bamboo fencing with net. They have filled their ponds with pumps from canals / rivers and tube well water to face the problem of less rain and long dry spells. To avoid the heavy mortality of the fishes they have used early harvest, liming, shading and water movement by beating of water for oxygenation. To overcome with the planktonic collapse the farmers have used cow dung, gobar gas slurry, use of khari, choker in the water and exchange of 50 percent water. To control the disease outbreak the farmers have adopted lime, KMnO4, medicines, neem leaves, banana stem etc.

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González-Fernández, Cristina, Beatriz Molinuevo-Salces, and Maria Cruz García-González. "Nitrogen transformations under different conditions in open ponds by means of microalgae–bacteria consortium treating pig slurry." Bioresource Technology 102, no. 2 (January 2011): 960–66. http://dx.doi.org/10.1016/j.biortech.2010.09.052.

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Zornoza, Raúl, Ángel Faz, Dora M. Carmona, Jose A. Acosta, Silvia Martínez-Martínez, and Arno de Vreng. "Carbon mineralization, microbial activity and metal dynamics in tailing ponds amended with pig slurry and marble waste." Chemosphere 90, no. 10 (March 2013): 2606–13. http://dx.doi.org/10.1016/j.chemosphere.2012.10.107.

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Kolay, P. K., and D. N. Singh. "Effect of zeolitization on physicochemico-mineralogical and geotechnical properties of lagoon ash." Canadian Geotechnical Journal 38, no. 5 (October 1, 2001): 1105–12. http://dx.doi.org/10.1139/t01-035.

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A common method to dispose of ash generated from coal-fired thermal power plants is to mix the ash with water and place the ashwater slurry in ponds or lagoons. Such a disposal system allows for the ashwater interaction. Alkalis present in the ash react with water, leading to zeolitization of the ash and changes in its overall properties. To simulate such interaction, controlled experiments have been conducted on a typical Indian lagoon ash, and the effect of zeolitization on the physicochemicomineralogical properties has been studied. The effect of zeolitization on the geotechnical properties of the ash has also been investigated in detail. It is believed that such investigations are essential for bulk utilization of the lagoon ash, particularly as a fill material, where properties like compaction, consolidation, and hydraulic conductivity are very important.Key words: lagoon ash, physical properties, chemical composition, mineralogy, geotechnical characteristics, zeolitization.

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Ngoc Minh, Bach, Huynh Hoan My, Hoang Kim Anh, and Ngo Ke Suong. "Optimization of protein extraction from green algae Chaetomorpha sp. by response surface methodology." Science and Technology Development Journal - Natural Sciences 3, no. 3 (December 22, 2019): 136–43. http://dx.doi.org/10.32508/stdjns.v3i2.864.

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Green brackish algae Chaetomorpha sp. are easily found in shrimp ponds in Mekong Delta, Vietnam. They can also be co-cultured with shrimps in brackish water shrimp ponds to increase shrimp health and yield. Chaetomorpha sp. algae contain high amount of protein from 10 to 20% w/w db, including water soluble protein and alkaline-soluble protein with over 88% total protein. Dried material were used for protein extraction by using cellulase enzyme (Crestone Conc., Genecor) and NaOH solution. In this research, we optimize the extraction condition of protein from green algae Chaetomorpha sp. by using response surface methodology (RSM). At optimal extraction conditions, dried material was used for protein extraction by using cellulase enzyme (Crestone Conc., Genecor) with the enzyme dosage of 121 UI/g db at 400C during 90 mins. After extraction, the slurry was centrifuged to separate the algae biomass residue to extract the alkaline-soluble protein. The protein extraction yield by using cellulase enzyme was 38.921 mg/g db. After that the, algae biomass residue was extracted by a 1.2% NaOH solution for 78 mins at 500C. The protein extraction yield was 68.651 mg/g db. The total protein extraction yield was 105.755 mg/g db. The extraction yield was increased 10.33% when using the response surface methodology. Concentrated algae protein can be used as a good protein source for food and feed products.

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Martínez-Pagín, P., A. Faz, and E. Aracil. "The use of 2D electrical tomography to assess pollution in slurry ponds of the Murcia region, SE Spain." Near Surface Geophysics 7, no. 1 (September 1, 2008): 49–61. http://dx.doi.org/10.3997/1873-0604.2008033.

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Dos Passos Santos, Ana Caroline, ALEXANDRA AMARO DE LIMA, and Igor Felipe Oliveira Bezerra. "EVALUATION OF SURFACE WATER QUALITY OF THE AREA OF INFLUENCE OF THE LANDFILL OF THE CITY OF MANAUS/AM." International Journal for Innovation Education and Research 7, no. 11 (November 30, 2019): 1185–95. http://dx.doi.org/10.31686/ijier.vol7.iss11.1986.

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This work aimed to evaluate the quality of surface water around the Manaus Solid Waste Landfill (ARSM), in which it is located near important waterways in a growing urban expansion area. During the collection period, the parameters pH, T, fecal coliforms, OD, DBO5, nitrate, phosphate, turbidity and total solids were monitored, where these are the main parameters for performing water quality index calculations. The results analyzed indicate contamination in the streams near the perimeter of the Landfill, where the possible origins for non-conformities can be problems in draining the leached and waterproofing system of the landfill ponds. The recovery of the quality of these water resources is essential, since it is an area with flora and fauna that are heritage, not only of the residents who occupy their surroundings, but also the population of Manaus who in the past enjoyed bathing and fishing areas in the streams currently affected by the slurry produced in the landfill.

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M., Krichevskaya, Malygina T., Preis S., and Kallas J. "Photocatalytical oxidation of de-icing agents in aqueous solutions and aqueous extract of jet fuel." Water Science and Technology 44, no. 5 (September 1, 2001): 1–6. http://dx.doi.org/10.2166/wst.2001.0239.

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Improper handling of jet fuel at abandoned military bases has resulted in heavy pollution of the soil and groundwater. Experimental research of photocatalytical oxidation (PCO) of jet fuel aqueous extract and aqueous solutions of de-icing agents was undertaken. The influence of different parameters - pH, concentration of substances to be oxidised, presence of inorganic admixtures, effect of OH• radical generators - on the PCO of solutions of de-icing agents and jet fuel aqueous extract was determined. The role of OH• radicals was found to be less important in determining the PCO rate. The PCO of organic pollutants was also investigated using a catalyst immobilised onto the surface of buoyant hollow glass micro-spheres. Attached titanium dioxide (TiO2) showed lower photocatalytical activity than when suspended in slurry, although it allows waters to be treated in simple shallow ponds without intensive stirring. The biodegradability of aqueous solutions of de-icing agents and jet fuel aqueous extract increased as PCO proceeded.

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Sońta, Marcin, Andrzej Łozicki, Magdalena Szymańska, Tomasz Sosulski, Ewa Szara, Adam Wąs, Gijs W. P. van Pruissen, and René L. Cornelissen. "Duckweed from a Biorefinery System: Nutrient Recovery Efficiency and Forage Value." Energies 13, no. 20 (October 10, 2020): 5261. http://dx.doi.org/10.3390/en13205261.

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This paper presents the results of an interdisciplinary study aimed at assessing the possibility of using duckweed to purify and recover nutrients from the effluent remaining after struvite precipitation and ammonia stripping from a liquid fraction of anaerobic digestate in a biorefinery located at a Dutch dairy cattle production farm. The nutritional value of duckweed obtained in a biorefinery was assessed as well. Duckweed (Lemna minuta) was cultured on a growth medium with various concentrations of effluent from a biorefinery (EFL) and digested slurry (DS) not subjected to the nutrient recovery process. The study’s results showed that duckweed culture on the media with high contents of DS or EFL was impossible because they both inhibited its growth. After 15 days of culture, the highest duckweed yield was obtained from the ponds with DS or EFL contents in the medium reaching 0.39% (37.8 g fresh matter (FM) and 16.8 g FM per 8500 mL of the growth medium, respectively). The recovery of N by duckweed was approximately 75% and 81%, whereas that of P was approximately 45% and 55% of the growth media with EFL0.39% and DS0.39%, respectively. Duckweed obtained from the biorefinery proved to be a valuable high-protein feedstuff with high contents of α-tocopherol and carotenoids. With a protein content in duckweed approximating 35.4–36.1%, it is possible to obtain 2–4 t of protein per 1 ha from EFL0.39% and DS0.39% ponds, respectively.

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Di Lorenzo, Tiziana, Grant C. Hose, and Diana M. P. Galassi. "Assessment of Different Contaminants in Freshwater: Origin, Fate and Ecological Impact." Water 12, no. 6 (June 24, 2020): 1810. http://dx.doi.org/10.3390/w12061810.

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Freshwater ecosystems cover over 15% of the world’s surface and provide ecosystem services that are pivotal in sustaining human society. However, fast-growing anthropogenic activities have deleterious impacts on these ecosystems. In this Special Issue, we collect ten studies encompassing five different factors of freshwater contamination: landfill leaks, nutrients, heavy metals, emerging organic contaminants and marble slurry. Using different approaches, the studies detailed the direct and indirect effects that these contaminants have on a range of freshwater organisms, from bacteria to vertebrates. Although the papers covered here focused on specific case studies, they exemplify common issues that are expanding in groundwaters, hyporheic zones, streams, lakes and ponds around the world. All the aspects of these issues are in dire need of being continuously discussed among scientists, end-users and policy-makers. To this end, the Special Issue presents a new free software suite for the analysis of the ecological risk and conservation priority of freshwater ecosystems. The software can support local authorities in the preparation of management plans for freshwater basins pursuant to the Water Directives in Europe.

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Okeme, Ilemona C., Thomas B. Scott, Peter G. Martin, Yukihiko Satou, Theophilus I. Ojonimi, and Moromoke O. Olaluwoye. "Assessment of the Mode of Occurrence and Radiological Impact of Radionuclides in Nigerian Coal and Resultant Post-Combustion Coal Ash Using Scanning Electron Microscopy and Gamma-Ray Spectroscopy." Minerals 10, no. 3 (March 7, 2020): 241. http://dx.doi.org/10.3390/min10030241.

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Natural radionuclide concentrations in coal and coal ash can occur at levels sufficient to raise potential health and environmental concerns when (re)suspended or disposed into the environment. To evaluate such concerns, this study characterized coal and simulant coal ash samples obtained from two Nigerian coal mines (Okaba and Omelewu) using high resolution gamma spectroscopy combined with scanning electron microscopy and energy dispersive spectroscopy. Discrete uraninite particles were observed dispersed within the coal ash samples, alongside U and Th containing mineral grains (monazite and zircon) with monazite the most abundant radioactive mineral particles. The pitted and cracked surface morphologies of these radioactive particles (with sizes between 10 μm and 80 μm) indicate their susceptibility for disintegration into more harmful and readily inhalable PM2.5 aerosol particles, with the potential to deliver a localized dose and cause chronic respiratory diseases. The results of activity concentrations and radiological hazard indices for the coal ash samples from both mines were between three and five times higher than world average in soil, which imply that these coal ash materials should be suitably contained in slurry ponds to prevent hazards due to increased risk of prolonged indoor exposure to gamma radiation, radon gas, and inhalation of liberated radioactive particles.

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Mandava, Sri, Lucas Pfeifer, Gretel D’Souza, and Mark Wilson. "Diabetes Induced Osmotic Demyelination of the Pons in a Patient on Peritoneal Dialysis." Journal of the Endocrine Society 5, Supplement_1 (May 1, 2021): A375. http://dx.doi.org/10.1210/jendso/bvab048.764.

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Abstract Introduction: Osmotic demyelination of the pons as a result of uncontrolled diabetes is a rare event. Here we present a unique case of central pontine myelinolysis in a patient with poorly controlled type 2 diabetes mellitus in the setting of peritoneal dialysis. Clinical Case: A 48-year-old male with a history of insulin-dependent diabetes mellitus, hypertension, non-ischemic cardiomyopathy, and end-stage renal disease, treated with peritoneal dialysis, presented to the hospital for slurred speech, inability to walk, and persistent hyperglycemia for 3 days. Approximately 2 years prior to admission, peritoneal dialysis was initiated for ESRD and poor cardiac function. The patient’s outpatient pharmacologic regimen was 30 units of glargine daily and glimepiride. On physical exam, there was evidence of aphasia, dysarthria, and muscle weakness (2/5 in bilateral upper and lower extremities) without muscle rigidity. Deep tendon reflexes were absent in the lower extremities, but sensation to light touch was intact throughout. On admission, the patient was found to be in a hyperosmolar hyperglycemic state without ketosis. Initial lab tests were significant for serum sodium: 138mmol/L (n=134–145 mmol/L), serum sodium corrected for hyperglycemia: 143 mmol/L, serum glucose: 419mg/dL (n=75–99 mg/dL), beta-hydroxybutyrate 2.1 mg/dL (n<4.4 mg/dL), and serum osmolality: 330mosmol/kg (n=275–305 mosmol/kg). Urinalysis showed glucosuria without ketonuria. The cerebrospinal fluid analysis showed protein 57, glucose 109, and WBC 3. Lab studies for meningitis/encephalitis panel were negative. During his 2 years of dialysis, his HbA1C increased from 7.6% to 14.3% (n<5.6%). CT brain without contrast showed midline hypoattenuation of the inferior pons without edema. Magnetic resonance imaging without contrast of the brain demonstrated a lobulated lesion in the pons measuring 1–2 cm that shows T2 hyperintensity without surrounding edema. He was then diagnosed with central pontine myelinolysis in the setting of chronic glycemic changes. Conclusion: Osmotic demyelination of the pons is typically associated with rapid correction of hyponatremia. We describe osmotic demyelination of the pons as a result of poorly controlled diabetes with normal sodium. To our knowledge, this is the first report of this event in association with worsening diabetes after the initiation of peritoneal dialysis.

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Cheng, Haiyong, Shunchuan Wu, Xiaoqiang Zhang, and Junhong Li. "A Novel Prediction Model of Strength of Paste Backfill Prepared from Waste-Unclassified Tailings." Advances in Materials Science and Engineering 2019 (October 31, 2019): 1–10. http://dx.doi.org/10.1155/2019/3574190.

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Paste backfilling is an important support for the development of green mines and deep mining. It can effectively reduce a series of risks of underground goaf and surface tailings ponds. Reasonable strength of backfill is an effective guarantee for controlling ground stress and realizing safe mining function. Under the combination of complex materials and local conditions, ensuring the optimal design and effective proportion for paste backfill strength is the bottleneck problem that restricts the safety, economy, and efficiency of filling mining. The strength developing trend of paste backfilling prepared from waste rock and unclassified tailings has been studied. Different levels of cement contents, tailings-waste ratios, and slurry concentrations were investigated through orthogonal design to obtain the relationship between the UCS and the multi-influential factors. Combined with the experimental results and the previous strength prediction models, the waste rock-unclassified tailings paste strength prediction model was proposed. Introducing the water-cement ratio, the cement-tailings ratio, the amount of cement, and the packing density that characterizing the overall gradation of unclassified tailings and waste rock, as well as the curing time, a strength prediction model of multifactors was developed. Moreover, the microscopic structure of the paste prepared from waste-unclassified tailings was analyzed with an Environment Scanning Electron Microscope (ESEM), and the influence mechanism was ascertained. The weight coefficient of strength development is carded in this paper, and the strength model of unclassified tailings-waste paste considering five factors is obtained, which is of great significance to guide the mining engineering.

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Journal articles on the topic 'Slurry Pond'

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