This invention relates to an improved method of separating non-acid chemicals from a water rich stream produced during a Fischer-Tropsch reaction. To create such a container which can be produced at low costs and is easy to handle, said container parts are surrounded by a removable envelope which consists of at least two parts. The integration of the two normally independent power converters results in a bidirectional power converter with nearly half the size, weight, volume, cost and complexity. A first configuration has two parts: an anchor member, forming the attachment with the target vessel wall and a coupling member, forming the attachment with the bypass graft vessel.