Several types of water are used in a power or process plant, and it is necessary to under­stand the differences correctly. • Raw water. Water received at the premises of the users regardless of any previous treatment. The sources may be a river, lake, well, mine water, and so on. • Treated water. Water that […]

Water is the raw material converted in the boiler into the end product—steam. The quality or purity of steam is only as good as the quality of input FW and its conditioning in the boiler. In its passage through the boiler, water • Is heated • Undergoes phase modification from liquid to vapor • Is […]

Introduction A peripheral understanding of water is essential for any boiler engineer. The aim of this chapter is to provide such a simplified overview. Both water and steam tend to dissolve some amounts of material they come in contact with, forming oxides, hydroxides, hydrates, and hydrogen. To protect the equipment, it is essential that water […]

Crude petroleum and its liquid residues left over in the process of distillation or cracking are the fuel oils used for steam generation. Crude petroleum is burnt for steam generation only infrequently, as the lighter fractions depress the flash point and present a fire hazard. Once the lighter fractions are removed, the oil becomes safe […]

Coals are complex substances that are geologically formed from ancient vegetation by the combination of time, pressure, and heat of the earth over several millennia. Depending on how long the vegetable matter has been subjected to these conditions, the resulting coals assume several properties. The most ancient coals under higher pressure would have converted practically […]

The entire power plant is built around the fuel, and there is perhaps no other parameter more important. A thorough understanding of the fuel—its burning characteristics, trans­portation inside and outside the boiler plant, its ash generation and disposal, the environ­mental aspects, and so on—is necessary for design, selection, operation, and maintenance of the boiler and […]

Steam is used in (1) many processes for mainly heating and (2) many ways for power gen­eration. Its utility is both in process industry and power plants. In the process industry it is produced for 1. Industrial processes involving mainly heating, steam drives, and other functions 2. Cogeneration (cogen) to provide other forms of energy, […]

Combustion is the self-sustaining rapid exothermic chemical reaction between the ele­mental C, H, and S of fuel with O2 from air due to their affinity. The products of com­bustion are CO2, H2O, and SO2 along with heat. C and H are beneficial constituents of fuel, producing heat, whereas S is the least heat generating and […]

Principles of Circulation Subcooled FW enters the drum, mixes with the circulating boiler water, and attains satura­tion temperature instantly, as the boiling, circulating water is several times the incoming water flow. This circulating water picks up its latent heat progressively from the hot flue gases to form steam as it goes around the evaporator circuits […]

What exactly is a fluid? • Fluid is a term used for both liquids and gases. • Vapor is an inexact term but is generally understood as gas near the saturation condition where liquid and gas phases exist together. • Water and steam, air and flue gas, and fuel oil and fuel gas are the […]