Höyrysäiliön

Höyrysäiliön refers to a steam accumulator, a type of pressure vessel designed to store steam under pressure in order to balance variations in steam demand and supply. The device typically consists of a steel shell containing water and steam, connected to a boiler, steam mains, and process equipment or heating networks.

Operation relies on the coexistence of liquid water and steam at or near saturation. When demand rises, additional steam is released from the accumulator to the system, while the boiler or a supplementary boiler maintains the pressure by producing more steam and feeding water back into the vessel as needed. The stored energy helps smooth boiler cycling, improve response times, and reduce fuel use in systems with intermittent or peak loads.

Design and safety features commonly include a pressure vessel with appropriate thickness, a pressure gauge, a relief valve or rupture disk, a feedwater inlet, and sometimes baffles or internal headers to control circulation. Materials are selected to resist high-temperature and corrosive conditions, and regular inspection is required to detect corrosion, scaling, or leakage. The operating pressures are generally modest by modern standards, but still require adherence to applicable codes and standards for pressure vessels.

Historically, höyrysäiliöt were used in district heating, industrial plants, and early power stations to improve efficiency and stability before the widespread adoption of more advanced energy storage and high-capacity boilers. Today, the concept survives in certain niche applications and is also discussed in the broader context of thermal energy storage and steam systems.