Stamicarbon B.v.

Unie Van Kunstmestfabrieken B.v.

Petrus F Hendriks

Rudolf Van Hardeveld

Cornelis Hoek

Arie Jansen

Willem B Van Den Berg

Ammonium orthophosphate products are prepared by reacting ammonia and phosphoric acid together at high speed under vigorous mixing conditions by spraying the reactants through a two-phase, dual coaxial mixer/sprayer and separately controlling the supply and axial outflow rate of the phosphoric acid at 1 to 10 m/sec. and the outflow rate of ammonia at 200 to 1000 m/sec. (N.T.P.). Thorough mixing and a homogeneous product is obtained by directing the outflow spray into a coaxial cylindrical reaction chamber of a specified size with respect to the diameter of the outermost duct of the sprayer/mixer. The product may be granulated on a moving bed of granules and adjusted in respect of the NH.sub.3 to H.sub.3 PO.sub.4 content by changing the concentration of the phosphoric acid and/or supplying additional ammonia to the granulation bed.

Two-phase spraying device and reaction chamber for the preparation of a

Process and device for the preparation of a product containing ammonium

Chemical enzymatic conversions are conducted by contacting an aqueous solution of the substrate with a granular immobilized enzyme, the substrate solution being passed through several series-connected, separate fluidized beds of the granular enzyme, while the enzyme particles are passed from one fluidized bed to the next countercurrently and against the direction of flow of the substrate solution. Multi-compartment reactor columns are also disclosed.

Enzymatic conversion process

A two phase sprayer and process are disclosed in which the sprayer has a liquid supply tube surrounded by a coaxial gas or gas mixture supply tube which extends beyond the length of the liquid supply tube where the gas flow surrounds and atomizes the expelled liquid. The sprayer has a unique structure in part characterized by a narrowed taper gas supply tube which converges towards the outlet at an angle of 70.degree.-90.degree. with respect to the sprayer axis. The internally-positioned, coaxial liquid supply tube is chamfered also at a similar 70.degree.-90.degree. angle, the gas and liquid tubes at their outlet being essentially parallel. The joint of the narrowing part of the gas tube and the outflow channel is rounded. These sprayers efficiently spray relatively large amounts of liquid at low gas velocities and are particularly adapted for spraying a mixture of urea and ammonia into a bed of reactive, fluidized particles to form melamine without destroying desirable features of the fluidized bed into which the urea/ammonia mixture is sprayed.

Process and device for spraying liquid

A process for preparing melamine

Growing community of inventors

Geleen, Netherlands

Petrus F Hendriks