Category: Blog

There is no way around the problem of corrosion in power plants. Especially the desire for high steam temperatures and the use of different fuels pose new challenges for boiler manufacturers. What is required are boilers that are both economical and durable.

Maximal thermal efficiency with minimal corrosion – that is only attainable when the flue gases reach the final superheater at the temperature sweet spot. In other words: Cooling of the flue gases in the radiation passes must run constantly and in a controlled manner (see Figure 1). This is only possible when the buildups on the walls are controlled during ongoing boiler operation. Five technologies for the cleaning of radiation passes in waste incineration plants have established themselves: shower cleaning, water cannons and wall blowers, rapping systems and the shock pulse generator (SPG). In the following, we briefly explain the working principles behind these technologies.

The Silbitz biomass power plant in Thuringia, Germany, produces electricity (5.6 MW) and district heat (3 MW) from waste wood. In order to keep its production competitive, a high degree of availability at the plant is required. This was not satisfactory in Silbitz. The reason was the furnace: Heavy slagging on the walls resulted in short boiler operation periods and frequent downtimes. Since 2011, four shock pulse generators have been cleaning the plant during ongoing operation. This has enabled the amount of slagging to be minimized and boiler operation periods to be lengthened in the long term.

Energy demands are increasing while resources are becoming ever more scarce. Alternative fuels are gaining ground but their residue levels are high. Utilizing fuels and energy sources more efficiently is thus become increasingly important. Increasing boiler efficiency [1] not only helps towards protecting the climate, it also helps to lower a plant’s operating costs.

Everyone knows them, everyone fears them: overheating corrosion in waste incineration plants. 4 causes all operators know - at the latest after reading this article.