water quality control criteria. In February 1961, these were stipulated by JIS B 8223 (titled "Water conditioning for boiler feed water and boiler water"). JIS B 8223, which stipulates the required water quality for boilers and turbines of thermal power plants, is regularly amended based on
2 Quality Considerations. Boiler feed water quality is limited owing to problems of (1) scaling, (2) corrosion, and (3) foaming. In order to avoid these problems, the quality guidelines shown in Table IV have been adopted. Data in Table IV show a major difference between cooling water and boiler feed water quality constraints, in that boiler feed water has a strong relationship between water quality and …
SiO 2 0.2 to 0.5 kcal·m –2 ·h –1 per degree C. This scaling is mainly caused by the presence of calcium salts (carbonates or sulphates) in the water. These salts are less soluble when hot than when cold or when there is an excessively high level of silica in relation to the alkalinity of the water in the boiler.
Feb 05, 2018 · Boiler control strategies must be developed to operate the boiler safely, reliably and efficiently under varying loads, fuel costs and emissions targets. In a Flow Control article, 4 Key Measurements For Optimal Boiler Control, Emerson's Bob Sabin, outlines these important measurements in achieving effective boiler performance. These measurements include drum level, fuel flow, air flow …
Water Quality Control Technology for Thermal Power Plants
Since water impurities cause boiler problems, careful consideration must be given to the quality of the water used for generating steam. The composition of boiler feed water must be such that the impurities in it can be concentrated a reasonable number of times inside the boiler, without exceeding the tolerance limits of the particular boiler
Characteristics of boiler feedwater - Lenntech
Water, Boiler Water and Steam Quality for Power Plants / Industrial Plants. This new guideline replaces the former "VGB Guideline for Boiler Feed Water, Boiler Water and of Steam Generators with a Permissible Operating Pressure > 68 bar, October 1988 Edition".
The percentage of boiler blowdown is as follows: The blowdown can range from less than 1% when an extremely high-quality feedwater is available to greater than 20% in a critical system with poor-quality feedwater. In plants with sodium zeolite softened makeup water, the percentage is commonly determined by means of a chloride test.