Friday, 13 August 2010
- Group: Process Automation Modelling
- Subject: New comment (1) on "A combined storage and mixing vessel"
Unit: UNIT (TK101)
EM: EQM01 (XV911, XV912, XV913, XV914), EQM02 (XV101, XV102, XV103), EQM03 (XV104, XV105, XV106, P102)
CM: VALVE (XV101-XV106, XV911-XV914), MOTOR (M101, P102), TRANSMITTER (WT101, TT104), DI (LSL102)
Phase: AGIT PHASE (agitator), JCKT PHASE (jacket), TXIN PHASE (tank transfer in), TXOT PHASE (tank transfer out), WGHT PHASE (weight)
(Equipment Phase Logic in Controller):
AGIT PHASE: Use agitator on-off command, motoe speed setpoint etc. phase parameters to control M101 start/stop and speed. LSL from WGHT PHASE can interlock the agitator for protecting purpose.
JCKT PHASE: Use Cool, Heat, temperature setpoint etc. phase parameters, and operate EQM01 valves matrix, compare with TT104, to control tank temperature.
TXIN PHASE: Use source route setpoint (eg. 1=Solvent, 2=Upstream1, 3=Upstream2), quantities setpoint etc. phase parameters and operate EQM02 valves matrix, compare with WT101, to transfer liquid into tank.
TXOT PHASE: Use destination route setpoint (eg. 1=Down Stream, 2=Drain), quantities setpoint etc. phase parameters and operate EQM03 valves matrix, compare with WT101, to transfer material out from tank. LSL from WGHT PHASE can also interlock the P102 for protecting purpose.
WGHT PHASE: Use LSL setpoint, density setpoint etc. phase parameters to monitor level and generating LSL alarm message etc.
I think for process engineer, it will be easy to combine these phases and create the different type recipes.
Here is a diagram with the equipment modules and phases shown
Wednesday, 11 August 2010
It can also be used to blend different liquids.
The Vessel Receives liquid from an upstream source, which may be a tanker delivery or an upstream vessel
If then Delivers liquid downstream
It can stores the liquid at a controlled temperature, This may be above or below ambient depending on the liquid
The liquid is stirred, but the rate of stirring should ensure that energy is not wasted, by stopping the agitator or varying the speed.
Receiving can take place at the same time as delivering downstream, but this is not normally the case.
It is an Operator decision whether to all this.
The downstream process takes the material in batches, and there may be several downstream demands. These together may exceed the capacity of the discharge pump, so an arbitration system is required.
The vessel must be flushed with solvent to prevent cross contamination of different liquids.
Tuesday, 14 July 2009
URSWriter.com is about Defining User and Functional Requirements for Process Manufacturing
It is intended to help people to write good specifications. And over the couple of years that it has been on the web it has been improved when I get time.
The web site has some unobtrusive advertising – if you are wondering, at present this just about covers the cost of the hosting and of course adds a few dollars to Google profits. And it also generates some interesting resources for further exploring the topic.