Views:7 Author:Site Editor Publish Time: 2017-04-11 Origin:Site
The longer the hot water boiler used, the more scale will be produced and the scale will gradually affect the efficiency of the hot water boiler. Here are some of the ways to remove the scale of hot water boiler.
1. Silicate scale
Composition of silicate scale is more complex. Scale of silicon dioxide content can reach more than 20%. Silicate scale is very hard and mostly white. Surface of scale is with thorns. Scale is easy to occur at the highest temperature of the boiler. Its main component is silicon calcium or magnesium olivine stone.
2. Sulfate scale
Main component of sulfate scale is calcium sulfate and more than 50%. Sulfate scale is mostly white, also slightly yellow. Especially hard, dense and feel creamy. The scale occur in the highest temperature and the evaporation intensity of the largest evaporation surface in the boiler.
Chemical cleaning method: Sulfate scale rarely produce bubbles in the hydrochloric acid solution and dissolve little. After adding 10% barium chloride solution, a large number of white precipitate will generate.
3. Carbonate scale
Composition of carbonate scale are calcium carbonate, magnesium carbonate. Calcium carbonate is mainly and more than 50%. Calcium carbonate is mostly white and also slightly yellow. Due to the different conditions of occurrence, it can be hard, dense scale, and more occur in the high heat intensity site. It can also be a loose soft scale and multi-junction born in low temperature area. Such as boiler economizer, the inlet pipe mouth and so on. General hot water boilers are mostly carbonate scale.
Chemical cleaning method: Carbonate scale in 5% hydrochloric acid solution, most of them can be solubled, and will produce a lot of bubbles at the same time. After the end of the reaction, insoluble is little in the solution.