ADVANCED HIGH-EFFICIENCY AND LOW EMISSION GAS-FIRED DRUM DRYING TECHNOLOGY

摘要

Drying is one of the most energy intensive industrial processes. Papermaking, drying of food, textile and pharmaceutical products requires significant amount of energy to evaporate excess water from the product slurry. The most popular drying method is drum drying that traditionally uses condensing steam for drum surface heating. The use of steam requires the drums to meet ASME codes for pressure vessels, which limits the steam pressure and consequently, the shell temperature that reduces the drying capacity. In most cases drying is also the temperature-critical aspect of product processing. Gas Technology Institute (GTI) together with its industrial partners has developed an advanced high efficiency gas-fired drum dryer concept based on combination of low-NO_x ribbon flame and advanced heat transfer enhancement technique (US Patent 6,877,979). The new approach allows a significant increase in the surface temperature of the drum dryer, thereby increasing the drying rate. The pilot-scale unit was designed, fabricated and successfully tested for the papermaking application.