Plate and frame filter is normally known as the imperativeness filter, which is likely the most widely used most easy operated device. It is more adaptable to a varied mixture of jobs. It ‘s one of the most economical agencies and provides the most satisfactory consequences in footings of lucidity of a solution. There are different filter fabrics to accommodate different sorts of slurry content.
The purpose of the experiment is to measure whether the home base and frame filter is able to filtrate the slurry at a rate of 40L/hr at a concentration of 50kg/cm3 in order to run into the company ‘s demands. The other purpose is to happen out if the rate of flow will drop relation to the bar accretion within the filter medium.
Three force per unit area values which include 0.2, 0.3 and 0.4 bars were tested for the experiment. After the experiment, it was concluded that the 0.3 saloon was the ideal force per unit area for a good public presentation by the home base and frame filter.
The hypothesis was to turn out that when the bar accumulates on the filter medium, it will increase the flow of the opposition. This was proven to be right after finishing the experiment.
Plate and frame filters were besides known as pressed filters. When it was foremost invented in the 1800s, the size was immense. Most significantly, it was hard to run due to the insufficiency of yesterday ‘s engineering. At that clip, the possibilities of modifying the equipment was limited ( Sweetland 1914 ) .
In 1927, the filter imperativeness happened to be one of the most normally used filter as it had a simple on the job rule and the ability to accommodate to assorted miscellaneous jobs. When engineering improved, Engineers felt that there was a demand to re-design home base and frame filter. The maker permitted the applied scientists to take parts of the filter that were needed to be modified. As more thoughts came into the image for alteration, the home base and frame filter design was upgraded to accommodate the application ( John 1927 ) .
In 1938, modern filters such as vacuity and force per unit area filters were invented and introduced. In malice of these newer filters, the home base and frame filter was still popular as it was able to retrieve more solids.Larger bar accretion will halt filtration rhythms and had the ability to accomplish efficient lavation of the bar to retrieve valuable merchandises for farther processing ( Philip1938 ) .
Figure 1: Olden yearss filter imperativeness ( www.water.siemens.com/ … /old_press_R.jpg )
The purpose of the experiment is to measure whether the home base and frame filter is able to filtrate the slurry at a rate of 40L/hr at a concentration of 50kg/cm3 in order to run into the company ‘s demands. The other purpose is to find if the rate of flow will drop relation to the bar accretion within the filter medium.
The hypothesis is that the Ca carbonate slurry production rate is at 40 liters per hr at a concentration of 50 kg/m3. When the bar accumulates on the filter medium, it will increase the flow of the opposition. At a changeless applied force per unit area, the filter medium opposition additions, diminishing the flow rate.
The procedure which separates solids from a suspension by agencies of a porous medium or screen is known as filtration. The filter medium acts as a consideration to retain the solids and steadily forms a bar while the clear filtrate will so be allowed to go through through. When the bar increasingly builds up on the medium, it increases the opposition to flux. Under changeless applied force per unit area, the rate of flow will increasingly diminish ( Singapore Polytechnic 2009 ) .
The procedure of filtration involves the flow of H2O through a farinaceous bed, of sand or another suited media, at a low velocity. The media retains most solid affair allowing the H2O to base on balls. The procedure of filtration is normally insistent to guarantee sufficient remotion of unwanted atoms in the H2O ( Ramstorp 2003 ) .
In a home base and frame filter imperativeness, the solid atoms are trapped within the frame compartment, between the two filter media held tightly by the home bases. When the compartment is about wholly filled with the bar, the operation will be stopped for remotion of the bar and subsequent killing of the filter unit before the following filtration.
Figure 2: Simple filtration ( hypertext transfer protocol: //en.wikipedia.org/wiki/Filtration )
3.1 Start Up Preparation
First cheques were done to guarantee that the home bases, frames have been stacked decently. The home bases and frames were arranged instead along the usher beams get downing and stoping with the ‘end plates ‘ . Seven home bases and six home bases were used in total.12 filter media were inserted between the home base and frames.
Line tracing was besides done to follow the flow from the provender armored combat vehicle through the home base and frame filter. The hydraulic valve V1 was closed and so the hydraulic clinch was adjusted utilizing the lever till a hydraulic force per unit area of 100 bars was achieved.
It was besides checked that the trickle tray was decently placed at the underside of the stack of home bases and frames after which V5, V6, V7 is closed. The blending armored combat vehicle T1 was filled with approximately 3 liters of H2O for the leak trial. Simultaneously valves V2, V3, V4, and V6 were to the full unfastened. It was besides checked that the filtrate mercantile establishment hosieries were placed decently in the fictile container.
The power to pump P1 was switched on and the force per unit area regulator R on the pump was adjusted to a force per unit area of about 0.3 saloon. Water was so allowed to go through through the filter ( Singapore Polytechnic 2009 ) .
3.2 Leak Testing
After the H2O is seen go forthing through the discharge pipes, the
system was checked for escape. Pump 1 was so switched off.
If no escape occurred, the experiment will be carried on to the following stage, if a escape was present, the hydraulic clinch was released and the alliance of the tonss of home bases and frames was checked and leak trial carried out once more.
V6 was closed, V7 was opened to run out out the staying H2O in the armored combat vehicle T1 and V7 was closed one time all the H2O has been drained from the armored combat vehicle ( Singapore Polytechnic 2009 ) .
3.3 Slurry Preparation
The commixture armored combat vehicle T1 was about filled with 20 liters of H2O and 1 kg of Ca carbonate was weighed out in a fictile jug. The scaremonger of the armored combat vehicle T1 was switched on and one kg of Ca carbonate was easy poured into armored combat vehicle T1 by agencies of a fictile funnel and the scaremonger was left to run continuously to guarantee a unvarying provender concentration ( Singapore Polytechnic 2009 )
Valve V6 was to the full opened and the filtrate mercantile establishment was placed in a fictile container. After which the pump P1 was started and half a minute was allowed for the flow and the observation of the force per unit area reading on the force per unit area gage PI2.
After which, clear H2O was poured into armored combat vehicle T1 to rinse the armored combat vehicle while the pump was still running. Thereafter, five liters of H2O was added to let it to blush the system and to forestall subsequent choking coils ( Singapore Polytechnic 2009 ) .
3.5 Clean Up
Pump P1 was so switched off and V6 was closed. Valve V1 was opened to let go of the hydraulic pump. Then the tonss of home base and frame were dismantled. The filter bars were scraped off gently from the filter media and the bar was discarded into the fictile container provided. Finally, the equipments, home bases, frame and filter media was cleaned and the on the job country was wiped and dried ( Singapore Polytechnic 2009 ) .
4. Consequences and Calculation
Number of tallies
Pressure at 0.2 saloon
Flow rate ( L /hour )
Pressure at 0.3 saloon
Flow rate ( L/hour )
Pressure at 0.4 saloon
Flow rate ( L/hour )
Table 1: Volumetric Flow Rate of slurry at a force per unit area of 0.2, 0.3 and 0.4bar
4.1 Pressure at 0.2 saloon
At 0.2 saloon norm of volumetric flow rate,
= 40.65 L/h
4.2 Pressure at 0.3 saloon
At 0.3 saloon norm of volumetric flow rate,
4.3 Pressure at 0.3 saloon
At 0.4 saloon norm of volumetric flow rate,
= 116.38 L/h
5.1 Evaluation Of Consequences
After carry oning the experiment it is proven that the filter imperativeness has met the capacity demand of 40L/h. Harmonizing to the consequences shown in Table 1, at 0.2bar, the mean volumetric flow rate is at 40.5L/h. Therefore the filter imperativeness is good suited even when runing at a low force per unit area. Following the consequences, at 0.3bar, the mean volumetric flow rate is 60.45L/h. Finally, at 0.4 saloon, the mean volumetric flow rate is 116.4L/h therefore, run intoing the capacity demand. And therefore it is so concluded that the filter ‘s optimal operating force per unit area is at 0.3 saloon. Traveling on to the turbidness of the filtrate collected, it is shown that the filtrate collected is really clear at the terminal of the experiment. Hence confirming that the home base and frame filter matches the demand of turbidness. Alternatively, to further better the lucidity of the filtrate, more home bases could be installed.
5.2 Problems Faced
One of the jobs encountered in this experiment is the manual cleansing of the filter. Since cleansing of the filter is clip devouring it would be wise to buy two filter imperativenesss. One of the imperativeness filters is used to get by with the down clip for cleaning the filter. The other filter would move as a standby filter, in instances whereby the filter has to be sent for serving or care intents. Second job faced was the escape in between the home base and frame filter. If the medium used was caustic it might do harmful consequence to non merely the people but besides to the environment.
5.3 Alterations To Be Made
Like every other experiment ; this experiment excessively has its ain defects. This home base and frame system has a regulator at the dorsum of the pump.
So as to invariably supervise the end product force per unit area of the pump a
technician is required to set the regulator at the dorsum of the pump.
So as to change the defect of the system, it has been decided that alteration of the system has to be done. To mensurate the differential force per unit area across the filter, a force per unit area differential gage has to be added.
There will be a demand to exchange over the slurry to a standby filter when the differential force per unit area additions. After which the filter bar from the filter home base and filter fabric can be washed off.
To forestall a technician to invariably supervise the system a control valve and a flow metre have besides been added in the system. The flow rate can so be monitored by the Distributed Control System ( DCS ) system. As for the pump, an add-on of another pump should be installed. Care will be made easier when the pump is down. Furthermore it will non impact the filtering processes as the pump acts as a standby pump.
The purpose of the experiment has besides been met in that ; the flowrate will drop relation to the bar accretion within the filter medium.
The hypothesis is besides proven to be right seeing that the home base and frame filter is able to filtrate the slurry at a rate of 40L/hr at a concentration of 50kg/cm3.
It is besides eventually concluded that 0.3 saloon is the most ideal force per unit area for the operation of the home base and frame filter.