Importance of Steam Accumulator in Boilers

Steam Boilers are generally designed for a certain capacity at which they could supply steam continuously which is also its maximum continuous rating. So, the steam boiler designed for higher steam requirements can be made to run on lower loads or lower steam demands but a boiler designed for lower loads cannot run on higher loads or higher steam demands.

Generally it is observed that the steam requirement in a process is not fixed and keeps changing with time. For some time period there might be lower load requirements than the steam boiler capacity while for some period of time there might be high load requirements. Low load requirements can be easily met by the boiler but high steam requirements cannot be met by this boiler as it is not designed for such capacity. This is where a steam accumulator plays an important role as they store steam generated by the boiler and use it as and when required.

Steam Accumulators are designed in such a way that when there is an excess of steam, that when lower loads are required than the boiler maximum load, the excess steam gets stored in an accumulator and when the process steam load requirement increases, the steam from both the boiler and the accumulator can be released to meet up the process requirement.

Installing steam accumulator would bring about a huge reduction in boiler size, thereby reducing the cost of a boiler, installation cost, operating cost and increased boiler efficiencies.

• Plant already having a boiler of a certain capacity but for some reasons the process load requirement increases for certain time period in a day while for other time, process load requirement falls even below the maximum capacity.
• Plant planning to install a boiler for their process must consider the average heat load requirement of their process for deciding the maximum boiler capacity, and for the overload conditions steam accumulator can be installed.

Deciding the capacity of steam accumulator is not an easy task as it requires full time monitoring the steam flow rates in a process and making an organized chart showing the excess steam generation and overload steam demand. This data is collected for at least 2 to 3 days and any other load variations are recorded. Then this data helps in calculating the maximum capacity of a Steam Accumulator.

Source – Steam Accumulator