Description

The main processing vessel is situated in a floor-standing stainless steel framework, which also houses a catalyst mixing tank, filter pump,

pressure leaf filter and vacuum pump. All equipment in contact with the process fluid is manufactured from stainless steel.

The hydrogenation vessel has a batch capacity of 25 litres.

It is a vertical cylindrical vessel, which incorporates a cooling/steam heating coil, hydrogen gas sparge ring, variable speed turbine agitator and baffle arrangement.

The hydrogen addition cycle results in an exothermic reaction and maintenance of the operating temperature is achieved by

circulatingmeteredcoolingwaterthroughthesubmergedcoolingcoil, whichremovestheexcessheatfromthereaction.

Initial heating to the reaction temperature is by steam, also in the immersed coil. A steam pressure control station enables pressures of up to 10.0 bar on the coil so that process temperatures of up to 180˚C can be achieved.

The turbine agitator is driven by a pneumatic motor through a mechanical seal in the lid of the vessel. Rotational speed is varied by adjusting the pressure of the compressed air driving the motor.

Amaximumspeedof2500rpm*canbeachieved.Thepropellermixer inthecatalystpreparationtankisalsodrivenbypneumaticmotorandis capableofrotatingatspeedsupto850rpm*.Pneumaticsareused

asthemotiveforceasthepresenceofhydrogengasrequiresminimal useofelectricalcomponents.Onlythefilterchargepumpandtheliquid ringvacuumpumparedrivenbyelectricmotor.

The centrifugal filter charge pump enables efficient filtering of the catalyst from the oil by the pressure leaf filter, which is a reusable filter requiring no replacement of the filter element. If necessary, filter aid in the form of a diatomaceous earth can be mixed in the catalyst tank and added to the oil charge prior to filtering.

The process vessel and filter are designed fully in accordance with theBS5500codeforpressurevessels.Vacuumlevelsof65mbarare achieved in the reactor vessel by the liquid ring vacuumpump.

Reduced system pressures are necessary to prevent oxidation during the heating cycle and assist in the removal of any water present in the oil. Also, the suction pressure is used to charge the vessel with oil and for the addition of catalyst and filter aid.