Steam drum design for direct steam generation

For the direct steam generation in solar fields, the recirculation concept has been demonstrated in several\udinstallations. Water masses in the solar field vary during transient phases, such as passing clouds. The volume of the\udsteam drum can serve as a buffer during such transients by taking in excess water and providing water storage. The\udsaturated steam mass flow to the superheating section or the consumer can be maintained almost constant during short\udtransients; therefore the steam drum plays a key role for constant steam supply. Its buffer effect depends on the right\udsizing of the steam drum for the prevailing situations. Due to missing experiences, steam drums have been sized under\udconservative assumptions and are thereby usually oversized. With this paper, experiences on the steam drum of the 5\udMWel TSE1 power plant are discussed for optimized future plant design. The results are also of relevance for process\udheat installations, in which saturated steam is produced by the solar field