Oxidation Proof Silicate Surface Coating On Iron Sulfides

The present method induces an oxidation-proof ferric silicate coating on iron sulfide such as pyrite and marcasite. The method includes the steps of placing the pyrite to be treated in a reaction vessel and leaching the pyrite with a coating composition including water, an oxidizing agent and a silicate coating agent. Examples of oxidizing agents include hydrogen peroxide, sodium hypochlorite, potassium hypochlorite and mixtures thereof. The silicate coating agent may be sodium metasilicate. In order to ensure the formation of the stable coating, the leaching is performed at a pH of 4-6 and more preferably 5. Additionally, the oxidizing agent is maintained at a concentration of substantially 0.6% by weight of the coating composition while the concentration of the silicate coating agent is maintained at at least substantially 1.8×10-3 M/l

Bituminous Fly Ash Release Potential Modeling and Remediation of Arsenic, Boron and Heavy Metals

In Kentucky, approximately 3 million tons of coal fly ash are produced annually at a disposal cost around $20 per ton. Moreover, disposal is becoming a major issue because of the ash\u27s potential to contaminate surface and groundwater with arsenic, boron, heavy metals, etc. Knowledge on the chemistry of fly ash is essential in developing a methodology that can predict release rate(s) and concentration(s) of chemical constituents of environmental concern (pollutants). Currently, there is major concern in the state how to dispose of safely the fly ash generated from the combustion of coal by electrical generating plants. Safe disposal of fly ash with respect to surface and groundwater protection depends on having the know-how and technology to evaluate the potential of a given fly ash to release toxic pollutants and 2) having the know-how to do something about it, assuming that a given fly ash is shown to have the potential to pollute. Kentucky is in major need of the above technologies because a major portion of its electrical needs comes from coal-fired electricity generating plants. The results of this study showed that Kentucky fly ashes were made of three types of solids: 1) chemically water stable solids (SiO, FeO, AlO), 2) chemically water reactive solids (SO4, BO3). and 3) metal-oxides (CaO, K2O) unstable at the pH range of natural water. The selected fly ashes varied from acidic to alkaline because of the chemical make-up of the source coal. Physical appearance of the samples tested varied depending on coal type and furnace. All fly ash samples were mainly composed of glass-like porous beads that varied in chemical composition with respect to Al/Si/Fe ratio and varied in pH from extremely low (pH near 3) to near pH 11. Alkaline fly ash samples were associated with high boron levels and exhibited extremely low potential pH buffering capacity. Potentiometric titrations revealed a fly ash PZCpH somewhere around 4.6 which was approximately midway between the PZCpH of iron-oxides and SiO2. Also, these data revealed that fly ash surfaces exhibited an apparent pH-dependent positive charge. A positive charge of approximately 40 cmolc kg-1, and a negative charge of approximately 40 cmolc kg-1 with intrinsic protonation and dissociation constants of 106.2 and 10-7.8 , respectively). Little if any charge was exhibited between pH 4 to 8.5. Low pH buffering capacity, low pH dependent charge and relatively low PZCpH appeared to make the fly ash samples tested extremely sensitive to pCO2 with respect to pH and boron release. Increasing pCO2 increased boron release but pCO2 had no influence on nickel release. This suggested that nickel was most-likely strongly chemisorbed. Nickel and cadmium adsorption isotherms showed that adsorption maximum took place above pH 6. The acidic fly ash showed a greater metal adsorption potential than the alkaline fly ash. Because boron (the major pollutant detected in the fly-ash samples tested) is weakly held, one should avoid burying such fresh fly-ash in water permeable waste disposal sites

Effect of Fertilizer Salts on Crop Production

Soil consists largely of mineral and organic matter, air, and water. Plants obtain nutrients from mineral and organic matter, oxygen from air, and they use water as a carrier of nutrients from the soil into the root and to the above ground portion of plants. Since soil water functions as a carrier of nutrients from solid fractions of soil into and through plants, it plays a very important role in plant nutrition. Because of this importance, correct chemical balance of the soil solution is necessary for best crop performance. This means that pH of the solution should be in the range 6.0 to 6.6 and the solution should not contain high concentrations of dissolved solid materials (salts)

H\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e2\u3c/sub\u3e Induced Oxidation Proof Phosphate Surface Coating on Iron Sulfides

The present method induces an oxidation-proof ferric phosphate coating on iron sulfide such as pyrite and marcasite. The method includes the steps of placing the pyrite to be treated in a reaction vessel and leaching the pyrite with a coating composition including water, an oxidizing agent and a phosphate coating agent. Examples of oxidizing agents include hydrogen peroxide, sodium hypochlorite, potassium hypochlorite and mixtures thereof. The phosphate coating agent may be potassium dihydrogen phosphate. In order to ensure the formation of the stable coating, the leaching is performed at a pH of substantially 5 and at a temperature of substantially 40° C. Additionally, the oxidizing agent is maintained at a concentration of substantially 0.1% by weight of the coating composition while the concentration of the phosphate coating agent is maintained at at least substantially 10-4 M/l

Does Use of Gypsum Improve Soil Structure in Kentucky?

Gypsum is sometimes recommended as a soil amendment in order to improve structure. Although this practice is often used for reclamation of sodic soils (Na+ saturated) in the western USA, it\u27s value in improving soil structure in Kentucky is questionable. The following discussion explains way

Semi-supervised classification and visualisation of multi-view data

An increasing number of multi-view data are being published by studies in several fields. This type of data corresponds to multiple data-views, each representing a different aspect of the same set of samples. We have recently proposed multi-SNE, an extension of t-SNE, that produces a single visualisation of multi-view data. The multi-SNE approach provides low-dimensional embeddings of the samples, produced by being updated iteratively through the different data-views. Here, we further extend multi-SNE to a semi-supervised approach, that classifies unlabelled samples by regarding the labelling information as an extra data-view. We look deeper into the performance, limitations and strengths of multi-SNE and its extension, S-multi-SNE, by applying the two methods on various multi-view datasets with different challenges. We show that by including the labelling information, the projection of the samples improves drastically and it is accompanied by a strong classification performance

The Effect of Oil Well Brines on Agricultural Fields and Water

What is Brine and Where Does it Come From? Brine is the salty water trapped in rock formations associated with oil and gas deposits. It consists mostly of sodium chloride but can also contain other things such as organics, bromide, some heavy metals and boron. Its source as a pollutant is usually oil stripper wells which produce less than 10 barrels of oil per day with typically a 10:1 ratio of brine to oil. Such wells are distributed throughout Kentucky and are often located on farmland. In some cases, brine rises to the land surface even where no oil wells are present

Formulation Enhanced Transport of a Soil Applied Herbicide

Because pesticides are applied as formulated particles and the affinity of the active ingredient for the formulation is higher than for the bulk water, we hypothesized that a formulation complex could affect active ingredient transport. Our objectives were to investigate the nature and extent of surfactant-atrazine-clay/oxide surface interactions. When atrazine and an anionic surfactant were dried onto plain or Fe-coated sand and leached, atrazine concentrations in the initial leachate were lower in the Fe-coated sand treatment. This was likely due to an electrostatic attraction between the sand and surfactant. When a nonionic surfactant was used, atrazine concentration in the initial leachate was lower through plain sand. This suggests that the affinity of the nonionic surfactant for the Fe-surface is lower than for the silica surface. Using FTIR spectroscopy we have determined that a nonionic surfactant and atrazine will partition into the interlayer of montmorillonite. Atrazine in the interlayer has important implications for herbicide mass transport. The desorption of atrazine will be diffusion controlled and hence less atrazine should be available for transport. However, should these clays become dispersed, they could act as a suspended, highly mobile phase for the particulate transport of atrazine

Dynamic Analysis of Double Wishbone Front Suspension Systems for Sport Motorcycles

In this paper, two alternative front suspension systems and their influence on motorcycle dynamics are investigated. Based on an existing motorcycle mathematical model, the front end is modified to accommodate both Girder and Hossack suspension systems. Both of them have in common a double wishbone design that varies the front end geometry on certain manoeuvrings and, consequently, the machine’s behaviour. The kinematics of the two systems and their impact on the motorcycle performance is analysed and compared to the well known telescopic fork suspension system. Stability study for both systems is carried out by means of root-loci methods, in which the main oscillation modes, weave and wobble, are studied and compared to the baseline model

Identification of Soil-Water Chemical Parameters for the Prediction and Treatment of Suspended Solids in Surface Water Reservoirs of Coal Mine Lands

High concentrations of suspended solids in coal mine sedimentation ponds are a factor in lowering water quality. Colloidal particle settling simulations were carried out in the laboratory to test the influence pH and dissolved solids have on concentration and settling rates of suspended solids. The results of the study reveal that the pH range of colloidal coflocculation for the samples tested is between 3.5 and 4.5. Furthermore, liming simulation of acidic sediments, as expected increased colloid dispersion. This increase was dependent on the magnitude of the sodium adsorption ratio (SAR). The greater SAR systems maintained a greater concentration of colloidal suspended particles. However, for the same SAR value when the ionic strength was increased from 4 meq L-1 to 8 meq L-1, sedimentation rate of colloidal particles decreased. The data also show evidence that for the same SAR values when substituting magnesium for calcium, the rate of particle settling increased for one sample but decreased for another. This unexpected behavior is under further investigation