Patent ID: 7572363

Claim:
A process for generating at least two steam streams having different purities during steam reforming in which at least two steam reforming units are operated in parallel, the first steam stream having a high purity and the second steam stream having a low purity, said process comprising: operating a plurality of steam reformers in parallel wherein the steam reformers are combined to form groups of at least two steam reformers, within which the entire amount of high purity steam generated in each group is generated in one of the steam reformers by exclusive vaporization of degassed and demineralized water and the entire amount of low purity steam generated in each group is generated in the other steam reformers of each group by vaporization of degassed impurity-containing water; wherein the degassed impurity-containing water is formed at least in part from the condensate produced within said group, and said degassed impurity-containing water being predominantly water.