Steam Raising Boilers
Contaminants commonly found in natural waters reduce operating efficiency of boilers and other boiler plant equipment, leading to increased maintenance costs and reduced production capacity. As water turns into steam and escapes into the steam distribution system, the water left behind in the boiler becomes more concentrated with contaminants and impurities which can damage the boiler. The objective of boiler water treatment is the prevention of water related problems in steam generating systems and associated equipment.
These problems include:-
- Deposit formation
This normally necessitates the installation of a pretreatment plant (e.g. base exchange softener or reverse osmosis plant) to remove hardness and other mineral salts from boiler feed water to meet BS2486 standards.
Thereafter chemicals are added to condition the water; sulphite and caustic for corrosion control, phosphate/dispersant for scale/sludge control. To produce pure steam, the boiler blow-down requirements are to keep the total dissolved solids in the boiler within 2,500-3,500 ppm.
Alchem Industries provide an extensive range of boiler water treatment programmes for all boiler types and pressures, from power plants on large industrial sites to small heating systems in commercial properties.
The British Standard 2486 'water treatment for land boilers' gives a detailed break-down on the requirements and conditions for boiler feed water and boiler water.
The directive basically lists the requirement for keeping the boiler scale and corrosion free, whilst ensuring the production of pure steam.