EAGLEBURGMANN ESPEY

Dryer

Media is dried industrially in a wide range of drying plants. In the great majority of cases, the material is moved around within heated, rotating pipes (drum dryers) or in tumbling containers (tumble dryers). The requirements of particular applications mean that these materials are frequently dried in a special gas atmosphere. Some of these applications can place extremely high demands on the sealing system due to very large seal diameters, or to the large forces generated by large shaft deflections. For decades Espey® carbon floating ring seals from EagleBurgmann Espey have proven the reliability, robustness and long service life through which stoppages are avoided.

APPLICATION EXAMPLE: ESPEY® WD500 FOR ROTATING REACTOR IN THE PET PROCESSING

Issue and chal­lenge:

Large industrial rotary drum inside a processing facility.

Urea is the most widely used nitrogen fertilizer agent in the world. Urea is manufactured in a synthesis tower at high pressure and high temperature through a process of high-pressure synthesis from liquid ammonia and a gas-water mixture with 88.7 % CO2. This gives rise to synthetic ammonium carbamide. Dehydrating while adding acid and heating, and further processing finally yield a white granulate – the fertilizer. The high pressures required by the process are generated in multi-stage radial integrally geared compressors. Each compressor stage requires a chamber seal with barrier gas and a leakage connection. For reasons of working safety, the highly compressed CO2 must never escape from the process area into the atmosphere.

Solution from EagleBurgmann Espey:

For this purpose, Espey developed the Espey® WD500. A shaft seal with barrier gas connection and four seal rings, designed for a shaft diameter of 1190 mm (46.85 “), a temperature of 220 °C (428 °F) and a slight vacuum. Because it is very time consuming to dismantle parts of the reactor shaft and its components, Espey designed a 4-piece housing in order to meet the demand for the simplest possible assembly. In addition, the seal has to withstand huge shaft movements (up to 25 mm (0.98 “) radially), and this is achieved through a special implementation of the floating seal rings. Unlimited axial shaft movement can be absorbed by the Espey sealing system. In order for the surroundings of the reactor to be entirely safe for the operating staff, the seal of the reactor, which is filled with CO2, incorporates a nitrogen barrier.