Technique

GPV stands for: Gravity Pressure Vessel

A gravity Pressure Vessel is a special kind of continue autoclave.

A composed vertical Tube with a build in heat exchanger.

 

The vertical position takes care of the pressure, The pressure is usually "for free".

Many GPV are self-contained, the incoming pressure is less then the outcoming.

Due the combination off the free pressure increase and the excellent heat exchanger, are the energy costs of a GPV system less then 90 percent of  the traditional autoclaves.

 

A GPV system is not suitable for all kind of autoclaves processes, only wet or slurry processes can be executed.

 

The principle is a long U-tube in the ground (Apeldoorn was 1200 m1) the exact length is dependent of the exact kind of process. The longer the tube, the more the pressure increases and the longer the residence time is.

 

 

 

This is how the process works.

 

 

A) Outside the reactor, the mixing of the solid particles  and liquid takes place and a
    slurry goes into the incomer tube. ( b)

    The ratio between solid and liquid is very important, this influences the crushing of
    the grains en the gas bubble effect.

 

 

b) The slurry is pumped  into the innertube and goes down. The pump pressure

    depends on the dimension of the reactor, solid fluid ratio and the position and

    capacity of the gasinjection points. (c)

 

c) In the innertube, there are several positions off gasinjection. Due the 3 phase
    behaviour (gas, liquid and solids) the process takes care off a perfect mixing and 
    crushing off the graines.

 

d) Due the  heat of the exothermic reaction, the temperature of the slurry is rising.

    The hot carbonated slurry takes care off heating up the incoming slurry.

 

e) The pressure and temperature are increasing as the slurry goes down.

 

f)  At the bottom, the innertube is open, so the slurry flows into the middle tube and
    proceeds upward.
    The middle tube is closed at the bottom and encircles the inner tube.
    The reaction parameters at the bottom are perfect, the highest pressure and
    temperature.

   

g) If necessary, the extensive heat can be take away by the sectioned cooling tube.

    At the surface the heat can be transformed into pressurized steam.

 

 

h) The slurry in the middle tube flows up and releasee the heat to the inner- and

    coolingtube. As the enclosed space is ringlike,  the upflowing liquid is in good

    contact with the downcoming tube.

    The temperature range and trend can be influenced by the coolingtube

 

i)  Depending on the requried exit conditions, it’s possible to cool the slurry
    extra.

 

f)  The slurry leaves the reactor and if necessary the slurry can be separated or has
     extra above ground treatments.