Apparatus for mixing a first fluid into a second fluid using a wedge-shaped, turbulence-inducing flow restriction in the mixing zone

An apparatus for mixing a first fluid into a second fluid, comprising:

• a housing having a flow chamber, the flow chamber defining a principal direction of flow for the second fluid, the flow chamber having first and second walls that converge in a wedge shape as viewed in a plane transversely to the principal direction of flow of the second fluid;
• a flow restrictor member disposed in the flow chamber, the flow restrictor member having first and second sides that converge in a wedge shape as viewed in a plane transversely to the principal flow direction of the second fluid;
• a first gap formed between the first side of the flow restrictor member and the first wall of the flow chamber;
• a second gap formed between the second side of the flow restrictor member and the second wall of the flow chamber;
• and
• means for introducing the first fluid into at least one of the first and second gaps, the means for introducing the first fluid being disposed in the region of said first and second gaps.