JP2002286708A - Compressive permeation testing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compressive permeation testing machine capable of favorably measuring the index, etc., of the compressiveness of an organic compound cake whose filtrating characteristic will easily vary depending upon the temperature in crystallization or the filtrating temperature of crystallization slurry. SOLUTION: The compressive permeation testing machine is composed of a cylinder split in upper and lower parts in such a way as connectable, a piston concentrical to the cylinder, a gauge part to measure the value of the load applied, a compression chamber located below the piston and bounded by a porous plate and a filter material, a liquid sump positioned in the lower part of the compression chamber, a permeating liquid inlet positioned in the lower side wall of the joint and leading to the liquid sump, a permeating liquid outlet positioned in the side wall at the piston top, and a jacket part installed on the side wall and the bottom surface of the cylinder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compression permeation tester and a method for measuring a compressibility index or a specific resistance of filtration of a wet cake of an organic compound using the tester. A compression permeation tester suitable for measuring the compressibility index or specific resistance of a wet cake of an organic compound in which the filterability in the initial filtration and the filtration after washing is liable to fluctuate depending on the temperature and the filtration temperature of the slurry after crystallization. And a method for measuring the compressibility index or the specific resistance of filtration of a wet cake using the tester.

[0002]

2. Description of the Related Art As shown in FIG. 1 (b), a compression permeation tester includes a cylinder connected by a joint (10) and capable of being vertically separated at a lower upper end (10 ') of the joint. A piston concentric with the piston, a gauge for measuring a load value applied to the top of the piston, a compression chamber located at the lower part of the piston, defined by two upper and lower perforated plates, and a lower part of the compression chamber A permeate inlet (7) leading from the side wall at the top of the piston to the perforated plate above the compression chamber; and a permeate passage located at the lower side wall of the cylinder joint and leading from the sump chamber. An apparatus comprising a liquid outlet (8) is known [“Revised 4th edition Chemical Engineering Handbook” 11
Pp. 40-1144, published October 25, 1978 by Maruzen Co., Ltd.].

[0003]

However, the above-mentioned known apparatus measures the compressibility index and specific resistance of filtration of an inorganic wet cake, and is obtained by the crystallization temperature and crystallization before filtration. There is a problem that it is not suitable for measuring the compressibility index and the filtration specific resistance of a wet cake of an organic compound whose filtration properties are liable to vary depending on the filtration temperature of the slurry.

[0004]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventor has found that in a known apparatus, the inlet and outlet of the permeated liquid are reversed, and a jacket portion is provided on the side and bottom surfaces of the cylinder. Provided that the compressibility index and the specific filtration resistance of a wet cake of an organic compound can be measured with good reproducibility, and the present invention was completed.

That is, the present invention provides (a) a vertically separable cylinder (2) connected by a joint (10), a piston (1) concentric with the cylinder, and a load value applied to the top of the piston. (6), which is located at the lower part of the piston, and is defined by two upper and lower perforated plates (4) and (4 ') and two upper and lower filter media (5) and (5'). A chamber (3), a sump chamber (11) located below the compression chamber, a permeate inlet (7) located on the lower side wall of the cylinder joint and communicating with the sump chamber;
A compression permeation tester comprising: a permeated liquid outlet (8) located on the side wall of the piston top; and a jacket part (9) provided on the side wall and bottom surface of the cylinder. Using the tester described in item a), the filter medium (5), the porous plate (4) and the piston (1) are kept, except for the lowermost porous plate (4 ') and the filter medium (5') in the compression chamber (3). ) Is removed, and a slurry comprising an organic compound solid and a liquid is charged into a cylinder in which a perforated plate (4 ′) at the lowermost portion of the compression chamber and a filter medium (5 ′) are present, and a filter medium ( 5) and one perforated plate (4),
In a state where a heat medium or a refrigerant at a desired temperature is passed through the jacket portion, filtration is performed by applying a load to the top of the piston, and the wet cake layer remaining in the compression chamber and the liquid storage chamber (1) are removed.
The present invention provides a method for measuring the compressibility index or specific resistance of a wet cake, wherein the filtrate collected in 1) is obtained, and then the filtrate is allowed to permeate upward into a wet cake layer in a compression chamber. is there. Hereinafter, the present invention will be described in detail.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The testing machine (a) of the present invention
Referring to FIG. 1A, a cylinder (2) connected by a joint (10) near the height of the compression chamber (3) and separable up and down at a lower upper end (10 ′) of the joint.
A piston (1) concentric with the cylinder, a gauge (6) for measuring a load value applied to the top of the piston,
A compression chamber located at the lower part of the piston and defined by two upper and lower perforated plates (4) and (4 '), and two upper and lower filter media (5) and (5'); and a lower part of the compression chamber , A permeate inlet (7) located on the lower side wall of the joint of the cylinder and communicating with the aforementioned sump chamber, and a permeate outlet (8) located on the side wall at the top of the piston. And a jacket (9) provided on the side and bottom surfaces of the cylinder. As the gauge part,
For example, a dial gauge is exemplified.

[0007]

EXAMPLES When the compressibility index or specific resistance of filtration of a wet cake is measured by using the above-mentioned testing machine (a), first,
Remove the bolts of the joints, then remove the filter medium (5), perforated plate (4) and piston (1) and make sure that the perforated plate (4 ') at the bottom of the compression chamber and the filter medium (5') are not removed. After confirmation, the filtrate, which has previously constituted a slurry together with the sample wet cake, is filled up to the bottom of the compression chamber below the perforated plate (4 '). Next, a slurry composed of an organic compound solid and a liquid is charged into the cylinder. The amount of the prepared slurry is adjusted so that the thickness of the wet cake after filtration described below is about 3 cm. After charging the slurry, the filter medium (5), the perforated plate (4) and the piston (1) removed earlier are inserted into a cylinder to perform filtration.

(I) After filtration, a weight having the smallest load is placed on the top of the piston, and the wet cake obtained by filtration is brought into a certain compressed state. During this time, the reduction of the dial gauge is checked, and the load value at the time when the numerical value no longer changes is recorded. At the time of filtration, the filtrate discharged from the permeate inlet (7) is stored, and the viscosity and, if necessary, the density are measured. (Ii) With no change in the dial gauge value, for example, as shown in FIG. 3, a female pipette (13), an L-shaped pipe (14), a filtrate charging pipe (15), and a three-way cock (1)
The stored filtrate is supplied from the permeate inlet (7) while the head is put on using the device constituted in 2).
At this time, degassing is performed using a three-way cock so that the above-described device, the permeate inlet, and the cavity in the piston are always filled with the filtrate. For deaeration, for example, in the state of the three-way cock shown in FIG. 3, the pipe (14) and the charging pipe (15) are filled with the filtrate, and then the three-way cock is moved in the direction of the permeate inlet (7) by 90 degrees.
It is performed by supplying the filtrate with the rotation. Next, the head (difference in height between the top of the liquid in the pipette and the permeate outlet) and the compressed wet cake layer when the cavity in the instrument, permeate inlet and piston were filled with filtrate. Is recorded with the head when the filtrate is completely permeated, and the permeation speed q of the filtrate is measured. ΔP below
Corresponds to the pressure (Pa) of the filtrate corresponding to the difference between the heads. Next, the weights are exchanged or added so that the load gradually increases, and the operations (i) and (ii) are repeated. When the measurement of the filtration (transmission) data is completed,
The wet cake is taken out, and after drying, the mass of the solid content is measured, and W of the following formula (1) is calculated.

Based on the obtained data, the filtration specific resistance α _p is calculated by the following equation (1). α _p = ΔP / (μ · q · W) (1) [where, α _p is a filtration specific resistance at a certain pressure (m / K
g), which corresponds to the ratio between the cake thickness and the weight of the weight. ΔP is the permeation pressure (Pa), μ is the viscosity of the permeate (filtrate) (Pa · s), q is the liquid permeation rate (m / s), and W is the solids per unit area (Kg / m ² ). . From the α _p obtained by the calculation, the average filtration specific resistance α _av and the compressibility index n of the wet cake are calculated using the following equations (2) and (3).

[0010]

(Equation 1)

[0011] α_p= Α₀・ (P_s/ p₀)ⁿ (3) [where α_avRepresents the average filtration specific resistance (m / Kg).
For example, "Detailed explanation Chemical engineering unit operation I" (Asakura Publishing Co., Ltd.)
(Published December 20, 1962) 402-407 pages,
As described in Example 8.3 of section 8.35, the above expression α_pReverse of
Taking the logarithm of the number on the vertical axis, p_sIs plotted on the horizontal axis.
It can be obtained from the figure integral at a constant ΔP. ΔP
Is the permeation pressure (Kg / cm^Two) And p_sIs the permeation pressure ΔP
In the wet cake obtained after filtration
Working stress (Kg / cm^Two) And p₀Is 1 kg / cm^Two
(Reference stress). p_sIs, for example, "Detailed description Chemical engineering
Unit operation I ”(Asakura Shoten Co., Ltd. December 1964
(Issued on the 20th) As shown in equation (8.37) on page 401,
Cake surface determined from weight of weight in permeation test
And the Kozeny-Carman equation
P required _xIt is calculated as the difference between And
Α calculated from the overtest result and the above equation (1)_pIs the above p_sof
Expressed as a function. α₀Is the filter at the above standard stress.
Overpressure 1kg / cm^TwoAverage filtration specific resistance per unit (m / K
g), where n is the compressibility index (wet order) of the wet cake
Element). ]

[0012]

According to (a) of the present invention, it is possible to allow a refrigerant or a heat medium to pass through the jackets provided on the side walls and the bottom surface of the cylinder, and to filter a wet cake sample of a compressible organic compound. Even in the case of a (permeation) test, the compressibility index and the specific filtration resistance can be measured with good reproducibility. Further, according to (a) of the present invention, since the permeate inlet is provided at the lower part of the compression permeation tester and the permeate outlet is provided at the upper part of the compression permeation tester, bubbles remain in the line through which the liquid passes. It is difficult to obtain a more accurate compressibility index and filtration specific resistance value. Further, according to (b) of the present invention, the filtrate obtained by the first filtration is passed under the wet cake layer remaining in the compression chamber while the medium at the desired temperature is passed through the jacket of the compression permeation tester. Thus, the compressibility index and the specific resistance of filtration of the organic compound slurry over a wide range of filtration temperatures can be accurately measured.

[Brief description of the drawings]

FIG. 1 (a) is a compression transmission tester of the present invention, and (b) is a known compression transmission tester.

FIG. 2 is an enlarged view of a lower part of a piston in the compression permeation tester of the present invention.

FIG. 3 is a diagram showing an apparatus composed of a female pipette, an L-shaped pipe, a filtrate charging pipe, and a three-way cock in the compression permeation tester of the present invention.

[Explanation of symbols]

1. Piston, 2. Cylinder, 3. Compression chamber,
4,4'-perforated plate, 5,5'-filter medium, 6-gauge section, 7-permeate inlet, 8-permeate outlet, 9-jacket section, 10-joint, 11-・ Sump chamber, 12 ・ ・
Three-way cock, 13 ・ ・ Mespipet 、 14 ・ Piping 、 1
5. Filtrate charging pipe

Claims (2)

[Claims] 1. A vertically separable cylinder (2) connected by a joint (10), a piston (1) concentric with the cylinder, and a gauge (6) for measuring a load value applied to the top of the piston. ), A compression chamber (3) positioned below the piston and defined by two upper and lower perforated plates (4) and (4 ') and two upper and lower filter media (5) and (5'); A liquid reservoir (11) located at the lower part of the compression chamber, a permeate inlet (7) located on the lower side wall of the joint of the cylinder and communicating with the liquid reservoir, and a permeate liquid located on the side wall at the top of the piston. A compression permeation tester comprising an outlet (8) and a jacket (9) provided on the side wall and bottom surface of the cylinder. 2. The filter medium (5), the porous plate (4), using the tester according to claim 1, except for the porous plate (4 ') and the filter medium (5') at the bottom of the compression chamber (3). ) And the piston (1), remove the perforated plate (4 ') at the bottom of the compression chamber and the filter medium (5').
A slurry composed of an organic compound solid and a liquid is charged into a cylinder in which a filter medium (5) and a porous plate (4) are present in order from the top, and a desired temperature is applied to the jacket. In a state where the heat medium or the refrigerant passes through, the piston is filtered by applying a load to the top of the piston to obtain a wet cake layer remaining in the compression chamber and a filtrate collected in the liquid storage chamber (11). A method for measuring the compressibility index or specific resistance of filtration of a wet cake, characterized by allowing the filtrate to pass upward through the wet cake layer.