Steam is essential for producing Alumina. Any limitations in the steam supply will impact directly on the total Alumina production rate.An issue that does impact on steam production in an Alumina plant is the fact that the steam can be in direct contact with the product. This can contaminate the condensate that is returned to the boiler, potentially limiting its output. Some plants address this problem by operating the boilers with high continuous blowdown, effectively using the boiler to purify the waste water stream. This results in the circulating boiler water accumulating relatively high levels of dissolved solids which can build up on the internal surfaces of the boiler and in time, lead to tube failures. Effective internal circulation is essential in these boilers.
Design Boiler’s broad range of specialised boiler design services and computer modelling resources are available to support the type of boiler problems that often occur in Alumina plants.
Boiler circulation issues: The internal circulation of several large coal fired alumina plant boilers has been analysed by Design Boiler. Please refer to here to more details on this capability and to these case studies for more details: Defective Boiler circulation- Furnace Wall Tube Failures and the Downcomer Instability.
Boiler plant uprating: Design Boiler investigated the possibility of uprating boiler steaming rates to increase a site’s total steam capacity and thereby increase its Alumina production rate. As a result of this investigation, the generation capacity of the boilers was able to be increased. A relevant case study that discusses a similar problem may be found here.
Boiler Efficiency and Acceptance Testing: Our personnel have been involved in plant efficiency and boiler acceptance testing for contract verification purposes. We are capable and experienced in applying ASME, ISO and British Standards acceptance testing methods for both fired and HRSG boilers.
Superheater Tube failures: Design Boiler were engaged to investigate the cause of frequent superheater tube failures. The primary cause was traced back to erosion caused by sootblowing and an ineffective ash removal system. After the ash removal system was repaired, the boiler returned to service without further superheater problems.
