Hydrogen gas and its use in Iron and Steel industry...

Hydrogen gas and its use in Iron and Steel industry Hydrogen is a chemical element, ranking first in the periodic table with element symbol of ‘H’. The (atomic number of hydrogen element is 1 and atomic weight is 1.008. It is the smallest atom in the universe and the simplest element in nature. Its molecule consists of two hydrogen atoms. It is the lightest gas, being about 1/14 times as dense as air. It has three isotopes named (i) protium, (ii) deuterium, and (iii) tritium. Pure hydrogen is odourless, colourless and tasteless. Hydrogen has lowest atomic weight of any substance and therefore has very low density both as a gas and a liquid. The vapour density of hydrogen at 20 deg C and 1 atmosphere pressure is 0.08376 kg/cum. The specific gravity of gaseous hydrogen is 0.0696 and hence, it has around 7 % the density of air. The density of liquid hydrogen at normal boiling point and 1 atmosphere pressure is 70.8 kg/cum. The specific gravity of liquid hydrogen is 0.0708 and is thus, it has around 7 % the density of water. Hydrogen is a liquid below its boiling point of -253 deg C and a solid below its melting point of – 259 deg C at atmospheric pressure. It is non-toxic but can act as a simple asphyxiant by displacing the oxygen in the air. When hydrogen is stored as a high-pressure gas at 250 kg/cum and atmospheric temperature, its expansion ratio to atmospheric pressure is 1:240. The molecules of hydrogen gas are smaller than all other gases, and it can diffuse through many materials considered airtight or impermeable to other gases. This property makes hydrogen more difficult to contain than other gases. Leaks of liquid hydrogen evaporate very quickly since the...

Worker, Work, and Working...

Worker, Work, and Working Work is related to the worker’s consciousness since ages. Systematic, purposeful, and organized approach to work is specific and unique human activity. In fact, work is a matter of a deep concern for both the management and the workers. It is important since it is central to the organizational performance. All the economic and social theories made earlier have focus on the work, since it is the means of production needed by the society. Though the work has been central to the human activity all along, organized study of work has not begun till the later period of the 19th century. Frederick W. Taylor was the first person in the recorded history who considered that the work deserves systematic observation and study. Taylor’s ‘scientific management’ which is the science of work, laid only the first foundations. In the scientific management of work, the worker is given less attention, and the knowledge worker receives even lesser attention. There has been plenty of loud thinking, but serious, systematic study has been confined only to a few aspects of working. There has been ‘industrial physiology, dealing with the relationship of such things as lighting, tool and machine speeds, design of the work place, and so on, to the human being who is the worker. To this effect, the fundamental work was done in the early years of 20th century, such as the fatigue and vision studies. Then, there has been ‘ industrial psychology’ which focuses on the aptitudes, that is, the relationship between the demands of specific manual work and the physical skill, mechanical coordination, and reactions of individual workers. Finally, there has been development with respect to human relations, which is, the study of the relationship between people working together, though in...

Ironmaking by Blast Furnace and Carbon di Oxide Emissions Jan14

Ironmaking by Blast Furnace and Carbon di Oxide Emissions...

Ironmaking by Blast Furnace and Carbon di Oxide Emissions It is widely recognised that carbon di-oxide (CO2) in the atmosphere is the main component influencing global warming through the green-house effect. Since 1896 the concentration of CO2 in the atmosphere has increased by 25 %. The iron and steel industry is known as an energy intensive industry and as a significant emitter of CO2. Hence, climate change is identified by the iron and steel industry as a major environmental challenge. Long before the findings of the Inter-governmental Panel on Climate Change in 2007, major producers of iron and steel recognized that long term solutions are needed to tackle the CO2 emissions from the iron and steel industry. Therefore, the iron and steel industry has been highly proactive in improving energy consumption and reducing greenhouse gas (GHG) emissions. In the present environment of the climate change, within the iron and steel industry, there is a constant drive to reduce energy costs, reduce emissions and ensure maximum waste energy re-use. In the traditional processes for producing iron and steel, emission of CO2 is inevitable, especially for the blast furnace (BF) process, which requires carbon (C) as a fuel and reducing agent to convert iron oxide to the metallic state, and hence is the main process for the generation of CO2 in an integrated iron and steel plant. Climate policy is in fact, an important driver for further development of the ironmaking technology by BF. Critically, amongst the challenges facing the BF operation is decarbonization. Significant steps have been made by the iron and steel industry to increase the thermal efficiency of the BF operation, but ultimately there is a hard limit in decarbonization, associated with the need for C as a chemical reductant. Since the 1950s,...

Coal Tar Pitch

Coal Tar Pitch  Coal tar pitch, derived from by-product coke ovens, is the preferred material for use as a binder in the manufacture of carbon and graphite electrodes. Coal tar pitch is a coal conversion product. Its IUPAC name is ‘Coal Tar Pitch, High temperature”. Its CAS number is 65996-32-2 and EINECS number is 266-028-2. It is the shiny, dark-brown to black residue produced by distillation of coal tar. Coal tar pitch contains a large number of substances. It is solid at room temperature and consists of a complex mixture of numerous polycyclic aromatic hydrocarbons (PAHs), their methyl and polymethyl derivatives, and heterocyclics, and shows a broad softening range instead of a defined melting temperature. The hydrogen (H2) aromaticity of coal tar pitch (ratio of aromatic to total content of H2 atoms) varies from 0.7 to 0.9. Production of coal tar pitch Coal tar pitch is currently produced from coal tar, which is a byproduct of high temperature coking of coal in the manufacture of metallurgical coke. The tar predominantly contains a mixture of bi- and poly-condensed aromatic hydrocarbons and also compounds with heteroatoms in rings (predominantly nitrogen bases from the quinoline and acridine series, 1 % to 2 %) and phenols (1 % to 2 %). Upon distillation, 8 % to 12 % of a naphthalene fraction, 5 % to 9 % of an absorption fraction, and 21 % to 26 % of an anthracene fraction, which boiled away to 360 deg ?, are separated. The residual part of the tar is the pitch which contains nonvolatile and low volatile substances, whose average yield is around 2 % of the coking coal charge used for high temperature carbonizing. The industrial production of coal tar pitch consists of the fractional distillation of the coal...

Employees and organizational responsibility...

Employees and organizational responsibility Employees, whether unskilled or skilled, manual, clerical, or knowledge worker, are required to take the burden of responsibility. For this, they need tools, incentives, and security. Organizational management normally expects every employee to be responsible and has focus on his job. The job has to make achievement possible. Though the job is not everything, yet it comes first. If other aspects of working are not satisfactory, they can spoil even the most achieving job. But if the job itself is not achieving, nothing else can provide achievement. This may appear to be silly, but the major approaches to managing the employee, throughout history, have focused on elements external to the job. For instance, several trade union leaders, while focusing on ownership, have, by and large, left unchanged the structure of jobs and the traditional practices of managing employees. Protectiveness focuses on welfare, i.e., on things like housing and health care etc.. These are very important, but not substitutes for job achievement. More recent solutions such as the ‘co-determination’, which certain trade unions are pushing to put union representatives on the board of directors and into top management but do not concern themselves with the employees’ job itself. The fundamental reality for every employee is the eight hours or so he spends on the job. It is this job, through which the great majority of the employees have access to achievement, to fulfillment, and to the organizational success. To enable the employee to achieve, he must therefore first be able to take responsibility for his job. This basically needs (i) productive work, (ii) feedback information, and (iii) continuous learning (Fig 1). Fig 1 Basic needs of employees for taking responsibilities It is foolish to ask employees to take responsibility for their...