Challenges in Recovery of Valuable and Hazardous Elements from Bulk Fly Ash and Options for Increasing Fly Ash Utilization

Beneficiation of fly ash should require for ensuring the removal of reactive elements to reduce the effect of hazardous impact on our atmosphere and can fill the demand for resources such as metals and rare earths. In this chapter, we concentrate to describe the responsible factors involve in fly ash beneficiation that has a great contribution to our environment. The purpose of the current study is to know the recovery of different minerals; maximum removal of the contaminant, reactivity and neutralization capacity of acid mine drainage (AMD) with fly ash and development of the cost‐effective method of disposal of fly ash are achieved. Different beneficiation techniques of fly ash and utilization of fly ash are explained

Significance Of ‘Karma Yoga’ In The Gita An Accomplishment Of Human Life

Karma yoga is an ancient principle of Indian Philosophy. Karma means action, yoga means the state. It suggests the way to live in the world without getting entangled in wrong and sinful action. One of the Hindu religious text Bhagavad-Gītā, Chapter three explain the teachings of Karma Yoga. Karma yoga is the performance of prescribed duties obligatory for everyone. In Karma Yoga, Lord Krishna explains how duty can be performed as abided by responsibility in different stages of life. Lord Krishna goes on to detail the reasons why these responsibilities are so important, the benefits of fulfilling them, the drawbacks of failing to do so, the paths that lead to bondage and the paths that lead to redemption, and so on. The Bhagavad-Gītā prescribes two things that are essentially required to practice Karma yoga: (1) the karma yogin should not have an attainment of the fruits of action and (2) He ought to perform his actions as they are suggested to him. It will also elaborate the concept of Niskamakarma, in this context Gītā says ‘Do your duty without aspiration of results.’ This paper will summarize the three important concepts of the Gita, viz. Karma yoga, Bhakti Yoga, and Jnana Yoga. Karma yoga leads to Jnana, Jnana leads to Bhakti. Bhakti leads to Salvation. Karma yoga is the foundation to the way of salvation (Mukti). Karma purifies the mind, helping growing Bhakti, which ultimately leads to Jnana. There cannot be Jnana without Karma yoga. Bhakti yoga and Jnana yoga also interlinked. Thus, the paper will try to analyze in a nutshell the importance of Karma yoga, and its significance to attain the highest aim of human life ‘Salvation’ (Mukti)

Processing and Characterization of Plasma Spray coatings of Industrial Waste and Low Grade Ore mineral on metal substrates

Emerging portable applications and the rapid advancement of technology have posed rigorous challenges to Metallurgical engineers for development of an efficient material which can sustain for long period at any type of environment. The foremost objectives are to develop required surface properties with economical process. Now-a-days the investigation explores the coating potential of industrial wastes. Fly-ash emerges as a major waste of thermal power plants. It mainly comprises of oxides of silicon, iron, aluminium, and titanium along with some other minor constituents. Fly-ash premixed with quartz and illmenite which are low cost minerals available in plenty are excellent candidates for providing protection against abrasive wear and resistant to erosion. Plasma spraying is gaining acceptance for development of quality coatings of various materials on a wide range of substrates. Utilization of such kind of industrial waste as coating material minimizes the cost of plasma spray coating deposition, which posed to be the major hindrance to its wide spread application due to high cost of the spray grade powders. Fly-ash+quartz+illmenite (weight percentage ratio: 60:20:20) is deposited on mild steel and copper substrates by atmospheric plasma spraying, at various operating power levels ranging from 11 to 21kW and then characterization of the coatings is carried out. The properties of the coatings depend on the materials used, operating condition and the process parameters. The plasma spraying process is controlled by the parameter interdependencies, co-relations and individual effect on coating characteristics. The particle sizes of the raw materials used for coating are characterized using Laser particle size analyzer of Malvern Instruments. Coating interface adhesion strength is evaluated using coating pull out method, confirming to ASTM C-633 standard. Deposition efficiency is an important factor that determines the techno economics of the process. It is evaluated for the deposited coatings. In view of tribological applications, hardness is one of the most required mechanical properties. Hardness measurement is done on the polished cross section of the samples using Leitz Micro- Hardness Tester. Coating porosity is measured by image analysis technique. Coating thickness is measured on the polished cross-sections of the samples, using an optical microscope. To ascertain the phases present and phase changes/transformation taking place during plasma V spraying, XRD analysis is made. The coating quality and behavior depends on Coating surface & interface morphology are studied with Scanning Electron Microscope. For wear resistance application, wear properties of these coatings are studied by “Air Jet Erosion Test Rig”. The erosion wear behaviour of these coatings is evaluated with angular solid particle erosion tests under various operating conditions. In order to optimize the surface property for different application, one of the challenges is to recognize parameter interdependencies; correlations and their individual effects on process so that the coating can be useful for a specific application. This challenge can be analysed/predicted by Artificial Inteligence Methods. Statistical analysis of the experimental results using Artficial Neural Network and Taguchi experimental design is been made. Spraying parameters such as impact angle, size of the erodent, standoff distance and impact velocity are identified as the significant factors affecting the coating tribological property. This work establishes that fly-ash+quartz+illmenite composite mixture can be used as a potential coating material suitable for depositing plasma spray coating. It also opens up a new pathway for value added utilization of this industrial waste and low-grade ore mineral

Dynamic Economic Load Dispatch of Hydrothermal System

A Quasi Oppositional Gray Wolf Optimization (QOGWO) algorithm has been used in this work to decipher the economic load dispatch of hydrothermal system. Dynamic economic load dispatch problem involves scheduling of committed generators to meet the load demand with minimum fuel cost and several constraints which are dynamic in nature. It is basically short-term hydrothermal scheduling (STHS) problems through cascaded reservoirs. Instead of pseudo-random numbers quasi-opposite numbers are used to initialize population in the proposed QOGWO method so that the convergence rate of GWO increases. The viability of the projected approach is verified in three standard multi-chain cascaded hydrothermal systems with four interconnected hydro systems. The load and number of thermal units differ from one system to another. Water transportation delay between interconnected reservoirs, Valve Point Loading (VPL) have been considered in different combination in three cases. The technique put forth with established superior to many recent findings for the STHS problems with increased complexities

Metallic Glasses: A Revolution in Material Science

Metallic glasses represent one kind of advanced material, very popular in recent decades. These materials are very adaptable like plastics for their manufacturability in very complex shapes. TPF (Thermoplastic forming) based processes seem very good method to process them. These materials can compete with plastics but have metallic properties. They behave as magnetic materials with less hysteresis loss and less eddy current loss making them suitable for transformer and MEMS (Micro-Electromechanical System) applications. These materials exhibit good corrosion resistance, hardness and toughness. Based on the property and application, metallic glasses are good rivals to plastics, metals and ceramics. Chemical composition and kinetics of supercooling of these materials are the areas where young researchers can focus attention with a view to their improvement

Wear: A Serious Problem in Industry

Wear is the damaging, gradual removal or deformation of material at solid surfaces. Causes of wear can be mechanical or chemical. The study of wear and related processes is known as tribology. Abrasive wear alone has been estimated to cost 1–4% of the gross national product of industrialized nations. The current chapter focuses on types of wear phenomena observed in the industries (such as abrasive wear, adhesive wear, fretting wear, fatigue wear, erosive wear and corrosive wear), their mechanisms, application of surface coating for the protection of the surface from the industrial wear, types of surface coatings, thermal spray coating, types of thermal spray coating and its application in industry to protect the surface from wear. The detail information about the wear phenomena will help the industries to minimize their maintenance cost of the parts

On the replacement of steel by NITINOL as coupling agent in automobile shaft

Automobile couplings generally fail due to excessive misalignment in shafts and torque overload which ultimately generates vibration in the assembly. These vibrations weaken the coupling structure and ultimately get transmitted to the shaft leading to fatigue failure. Additionally, the complexity in the design of standard coupling is related to lower durability. In this system, when the radial space is larger it trigger a bulkier transmission. Shape memory alloy such as NITINOL is a special class of smart material that possesses super-elasticity which means it can retain deformation of about 8%. This material has a high degree of strength, greater elastic and shear modulus than existing coupling materials such as steel, and have unique vibration damping features. Coupling made of NITINOL is simple in design and requires lesser space with minimal maintenance. They provide higher durability and are much reliable in operation over a wide range of temperatures. This paper aims to review the NITINOL material used in coupling technology industries and the parameters governing its shape memory effect. The knowledge gathered from this work enable to further extend the technological contribution of NiTi coupling at large scale production in the automobile sector with direct effect on longer life for the transmission system

Current global scenario of sputtered deposited NiTi smart systems

This review provides details of the global scenario on the recent development and application of NiTi smart metal shape memory alloys (SMA). It mainly focuses on the dc/rf magnetron sputtering fabrication technology of nitinol thin film, which is a prominent structural material for many miniaturised systems. The sputtering parameters and their influence on the smart mechanism of the NiTi thin film has highlighted. The application of NiTi SMA at industrial scale from aviation industries to medical industries was discussed. The raised challenges within various applications were addressed, discussed and we have proposed possible way to overcome these limitations