Development of Flotation Reagents with Chelating Functional Groups

Recently in search for new methodology for flotation separation of complex, studies have been directed to develop reagents with chelating functional groups. Some of the chalating reagents have been successfully utilised as flotaids. This papers presents the design, selectivity and development of chelating type flotation reagents. The chemistry and applications of chelating type reagents for flotation of complex Indian ores are presented. The general mechanism of chelating reagent-mineral interaction is highlighted

Studies on De-Ashing of Non-Coking Coal by Froth Flotation

This paper presents the results of flotation studies carried out on a non-coking coal sample for reduction of ash. The effects of various process parameters on the floatability of coal have been studied. The effects of ultrasonication and emulsification of the oily reagents have been studied on the flotation behaviour of coal. The data have been analysed kinetically using first order model. It was found that ultrasonication of the oily reagents adds to the selectivity of separation while emulsification improves the recovery of carbon values. The improvement in the flotation performance was attributed to the fine dispersion and selective adsorption of the oily reagents caused due to ultrasonication and emuls-ification

Froth Flotation and its Application to Concentration of Low Grade Iron Ores

Froth flotation is a process used to separate minerals, suspended in liquids, by attaching them to gas bubbles to provide selective levitation of the solid particles. It is most extensively used process for the separation of chemi-cally similar minerals, and to concentrate ores for econo-mical smelting. Flotation is a selective process and can be used to achieve separation from complex ores such as lead-zinc, copper- zinc etc.Initially developed to treat the sulphides of copper, lead, and zinc, the field of flotation has now expanded to include oxides, such as hematite and cassiterite, oxidised minerals, such as mala-chite and cerussite, and non-metallic ores, such as fluo-rite, phosphates, and fine coal

Generation of Value Added Product by Beneficiation of Barite Waste

One of the largest indigenous manufacturing plants of barium chemicals is located at Cuddapah in Andhra Pradesh. During production of Barium carbonate, two types of rejects (flue ash and sludge) have been generated and accumulated for the last few decades at Cuddapah plant. Earlier, briquetting of charge was suggested to restrict physical losses of material as flue ash. Afterwards, to generate product, having >90% barium sulphate which could be reused, studies have been carried out with currently produced rejects. Detail investigations suggested separate treatment of sludge because the flue ash sample was found to be suitable as feed to the reduction circuit. Both gravity and flotation processes were found to generate product meeting specifications. It was also found that more than 55% of the combined rejects currently generated at Cuddapah plant could be used again for the production of barium carbonate. In the process, recovery of barite value could be more than 65%

Iron Ore Resources and Beneficiation Practices

Iron and Steel Industry provides foundation for indust-rial development of a country. The per capita consumption of steel is considered as one of the important parameters of a nation's prosperity. Iron ore is the basic raw mater-ial for iron and steel making. The world reserves of iron ore are estimated to around 370 bill on tonnes. The prin-cipal minerals of iron are the oxides(hematite and magne-tite), hydroxide (limonite and goethite) and carbonate (siderite). In nature the commercial deposits are mostly of bed type, although deposits of magnetic, contact meta-somatic and of a replacement nature also exist. In many cases, ground water circulation and weathering have resul-ted in concentration of the ore from primary sources. The major iron ore producing countries in the world are the Australia, Brazil, Canada, China, India, USA, Russia, Kazakhstan, South Africa, Ukraine and Sweden. Pre Cambrian banded iron formations containing 30% or more of iron are the predominant sources of iron

Gravity Concentration of Iron Ore

Gravity concentration process is the oldest beneficiation method known to mankind. This is a physical process and exploits the differences in densities of minerals to bring about a separation. Although with the advent of froth flotation, the relative importance of gravity concentrat-ion has declined in twentieth century but still on an average higher tonnage of material is treated by gravity concentration than flotation. The gravity separation processes are comparatively cheap and environmentally friendly. It finds immense application in the processing of iron ores besides coal, beach sands, gold, diamonds, platinum, baryte, fluorspar, tin, tungsten ores etc

Influence of Operating Variables on Flotation of High Ash Coking

The paper deals with the results of flotation studies carried out on a high ash coking coal sample. The influ-ence of various operating parameters such as collector and frother dosage, pH of the pulp, pulp density, aerat- ion and agitation were studied in a wide range. The flotation performance was assessed in terms of recovery, grade, selectivity index and flotation rate constants. The flotation rate constants were computed using a modified first order rate equation. Results have been discussed based on the analysis of the flotation data

MANAGEMENT OF FLEXION CONTRACTURE OF HAND: AN EXPERIENCE IN A TERTIARY CARE INSTITUTION

Abstract The flexion contracture involving the hand arise out of a variety of reasons which can be due to Post burn contractures involving palm or digits; flexion contracture of palm or digits due to Dupuytren’s contracture; post traumatic flexion contracture and developmental anomaly of the digits as Camptodactyly. A prospective study was conducted on patients with flexion contractures involving the hand needing correction presenting to OPD of the Post Graduate Department of General Surgery, Government Medical College, Jammu over a period of 12 months w.e.f. 1st November 2021 to 31stOctober 2022. All the patients were treated as in patients (after admission). The clinic-epidemiological profile of patients was noted and treatment modalities were planned as per the type of deformity.In the Management of Flexion Contracture of Hand, Objective of release was to achieve a functional hand. Stress was laid on post operative splintage and physiotherapy for better functional outcome

Coal Preparation - Recent Trends

Indian coal reserves constitute about 1% of the world reserve; the gross reserve is 1,92,884 million tonnes as on 01-01-1990, including Gondwana coalfields of tertiary coals (with high organic sulphur of North Eastern Coal-field) and tertiary lignite in Neyveli area etc., as shown in Table 1. Out of this, the coking coal reserve is only 28,690 million tonnes which is only 15% of the total. Again, out of the total coking coal (Table 2), hardly 18.5% is prime coking coal and about 27.5% is high volat-ile medium coking coal, a part of which is presently beneficiated for utilisation as blend charge for the coke ovens. But the low volatile medium coking coals comprising about 47.7% of the coking coal reserves remain unutilised or used in thermal power plants for want of suitable technology for their beneficiation

Optimized Neural Network Model to Characterize the Effects of Process Parameters on the Separation Efficiency of Iron Ore by a High Intensity Magnetic Separator

An improved and optimized multi-input-multi-output (MIMO) neural network model has been developed to predict the output parameters e.g grade and recovery to characterize the separation behavior of a high intensity magnetic separator for processing iron ore in the particle size range of 75~300 m. The input parameters in the Neural model comprises of feed composition, % Fe, % SiO2, %Al2O3 and process parameters such as particle size, pulp density and magnetic field intensity. The effect of process parameters on the separation efficiency was characterized by conducting a sensitivity analysis. The neural network architecture has been optimized using an efficient gradient based network optimization algorithm to minimize the training error rapidly. The model is based on the data generated from WHIMS experimental investigations. There has been an excellent agreement between the optimized model predictions with the measured values pertaining to recovery and grade for magnetic separation. This is depicted by the regression fit generated between the predicted and measured values