Patent ID: 8721840

Claim:
An apparatus for admixing a gaseous or liquid substance into a fiber suspension, said apparatus comprising: a tubular body defining a space that forms a flow channel for the suspension, the body includes an inlet and an outlet for the fiber suspension arranged to allow the suspension to flow through the flow channel in an axial direction, a tubular static feed member extending into the flow channel transversely against a flow direction of the suspension, the tubular feed member comprising a conduit configured to direct the gaseous or liquid substance into the feed member and having a cylindrical wall provided with openings for feeding the gaseous or liquid substance from the feed member into the flow channel, at least one protrusion arranged on an inner surface of the tubular body proximate to the feed member, a throttling member arranged in the flow channel downstream of the feed member in the flow direction of the suspension, and a mixing chamber in the flow channel between the feed member and the throttling member, wherein the tubular feed member is attached to the tubular body.