The Computer Controlled Plate and Frame Filter Press (AG-378) has been designed to demonstrate the filtration and clarification processes suitable for chemical, pharmaceutical, food and beverage industries, etc.Filtration is the separation of solids from liquids by forcing the liquid to flow through a porous medium and depositing the solids on the medium. A filter aid is a finely divided material which, when added to the liquid to be filtered, helps to control the flow and solids removal. Plate and frame filters, or filter presses, are batch-operated units, in which the suspension is filtered through the surface of plates, forming a cake within the supporting frames. The filtrate is collected through special piping and the cake is discharged when the operation is stopped for cleaning.A suspension is prepared in a feed tank and is transferred through a centrifugal pump into the plate and frame press. This pump ensures that the solids remain suspended and do not settle.The filter plates are grooved and covered over with filter clothes. Filter cloth (or filter media) retains the solid particles of the suspension, which fills the frame plates, whilst the filtrate passes through the filter media or filter cloth. The filtrate flows through the collecting pipe and is collected in the filtrate tank. The solid material is separated off from the filter cloth, where it forms a growing filter cake. As the filter cake becomes thicker, its flow resistance also increases. A selection of different grades of filter media is also supplied, suitable for: pre-coat filtration, coarse clarifying, polishing and sterilisation.The flow rate through the plate and frame filter press is adjusted by an actuator. The suspension passes through three pressure sensors and one flow sensor on its way. The initial temperature of the suspension and the final temperature of the filtrate can be recorded with two temperature sensors. A portable turbidity meter allows the solid concentration of the filtrate to be determined.Process control is done from the computer PC, using control software. This software will allow an automatic control (PID) of the variables involved in the process. That will make the work easier. This Computer Controlled Unit is supplied with the Computer Control System (SCADA), and includes: The unit self + a Control Interface Box + a Data Acquisition Board + Computer Control and Data Acquisition Software Packages, for controlling the process and all parameters involved in the proces
1.- Learning the fundamental principle and operation method of a plate and frame filter press.
2.- Study of filtration and clarification processes.
3.- Demonstration of pre-coat filtration, coarse clarifying, polishing and sterilisation.
4.- Production of a suspension.
5.- Formation of a cake.
6.- Fundamentals of cake filtration. Demonstration of Darcy’s Law.
7.- Turbidity versus concentration calibration straight line.
8.- Study of the plate and frame filter press at constant pressure.
9.- Study of the plate and frame filter press at constant flow.
10.- Variation in time of filtrate quantity and solid concentration in filtrate.
11.- Mass of filter cake in function of filtrate quantity.
12.- Determination of medium and cake resistance.
13.- Filter cake washing and dewatering.Additional practical possibilities:
14.- Sensors calibration.
15.- Influence of the number of frames and filters in the filtration process.Other possibilities to be done with this Unit:
16.- Many students view results simultaneously. To view all results in real time in the classroom by means of a projector or an electronic whiteboard
17.- Open Control, Multicontrol and Real Time Control. This unit allows intrinsically and/or extrinsically to change the span, gains; proportional, integral, derivate parameters; etc, in real time.
18.- The Computer Control System with SCADA and PID Control allow a real industrial simulation.
19.- This unit is totally safe as uses mechanical, electrical and electronic, and software safety devices.
20.- This unit can be used for doing applied research.
21.- This unit can be used for giving training courses to Industries even to other Technical Education Institutions.
22.- Control of the AG-378unit process through the control interface box without the computer.
23.- Visualization of all the sensors values used in theAG-378 unit process.