CN114544421A - Sludge dewatering performance measuring device and using method - Google Patents
Sludge dewatering performance measuring device and using method Download PDFInfo
- Publication number
- CN114544421A CN114544421A CN202210174409.XA CN202210174409A CN114544421A CN 114544421 A CN114544421 A CN 114544421A CN 202210174409 A CN202210174409 A CN 202210174409A CN 114544421 A CN114544421 A CN 114544421A
- Authority
- CN
- China
- Prior art keywords
- sludge
- piston
- dehydration
- filtrate
- valve
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000010802 sludge Substances 0.000 title claims abstract description 114
- 238000000034 method Methods 0.000 title claims abstract description 25
- 238000006297 dehydration reaction Methods 0.000 claims abstract description 50
- 230000018044 dehydration Effects 0.000 claims abstract description 47
- 238000001914 filtration Methods 0.000 claims abstract description 25
- 239000000706 filtrate Substances 0.000 claims description 32
- 238000007789 sealing Methods 0.000 claims description 18
- 238000006073 displacement reaction Methods 0.000 claims description 15
- 239000007788 liquid Substances 0.000 claims description 13
- 238000004891 communication Methods 0.000 claims description 9
- 239000010410 layer Substances 0.000 claims description 8
- 239000000463 material Substances 0.000 claims description 8
- 230000006835 compression Effects 0.000 claims description 6
- 238000007906 compression Methods 0.000 claims description 6
- 239000002356 single layer Substances 0.000 claims description 4
- 230000001360 synchronised effect Effects 0.000 claims description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 17
- 238000001514 detection method Methods 0.000 abstract description 14
- 238000005259 measurement Methods 0.000 abstract description 10
- 238000011156 evaluation Methods 0.000 abstract description 6
- 238000003825 pressing Methods 0.000 abstract description 3
- 238000010521 absorption reaction Methods 0.000 description 7
- 230000001143 conditioned effect Effects 0.000 description 2
- 239000012065 filter cake Substances 0.000 description 2
- 238000004065 wastewater treatment Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009264 composting Methods 0.000 description 1
- 230000003750 conditioning effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000010881 fly ash Substances 0.000 description 1
- 238000010169 landfilling Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000012466 permeate Substances 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000003828 vacuum filtration Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N5/00—Analysing materials by weighing, e.g. weighing small particles separated from a gas or liquid
- G01N5/04—Analysing materials by weighing, e.g. weighing small particles separated from a gas or liquid by removing a component, e.g. by evaporation, and weighing the remainder
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Treatment Of Sludge (AREA)
Abstract
The invention provides a sludge dewatering performance measuring device and a using method thereof. The invention adopts a mechanical pressing and data acquisition system, so that the detection result is more consistent with the mechanical press-filtering dehydration condition, and the detection process has higher automation degree because the detection process records the amount of filter liquor in real time. The method directly estimates the specific resistance of the sludge according to the inflection point of the linear region, does not need to measure the water content of the mud cake, and has short measuring process time and higher accuracy and repeatability. In addition, the method provided by the invention can simultaneously measure the specific resistance and compressibility coefficient of the sludge under the condition of not replacing the sludge, simplifies the measurement steps and realizes the comprehensive evaluation of the sludge dewatering performance.
Description
Technical Field
The invention relates to a device and a method for measuring sludge dewatering performance, in particular to a device and a method for measuring sludge dewatering performance designed based on a mechanical filter pressing principle, and belongs to the technical field of measurement of sludge dewatering performance analysis.
Background
A large amount of sludge is generated in the wastewater treatment process, and the treatment cost of the sludge directly influences the operation cost of the whole wastewater treatment system. Generally, sludge is dewatered before final disposal (e.g., landfilling, incineration, and composting) to reduce the water content and volume of the sludge. The evaluation of the sludge dewatering performance has important significance for the evaluation of the sludge dewatering process. At present, the evaluation indexes of the sludge dewatering performance mainly comprise: capillary water absorption time (CST) and sludge Specific Resistance (SRF).
The capillary water absorption time refers to the time required for sludge water to permeate a certain distance on the filter paper, and can rapidly represent the water filtration performance of the sludge. However, the capillary water absorption time is easily influenced by the sludge concentration and the detection temperature, so that the capillary water absorption time has large fluctuation. The sludge specific resistance refers to the resistance of a filter cake on a unit filtering area. The specific resistance of the sludge is mainly measured by a vacuum filtration method, and is not easily influenced by the concentration and the temperature of the sludge. However, in the sludge specific resistance measurement process, manual operation is usually complicated (such as manually adjusting pressure and reading filtrate volume), and the stability of the vacuum system is poor, so that the result is greatly influenced by the operation of experimenters. In addition, the water content of the mud cake needs to be additionally measured (usually measured by a drying method) in the calculation of the specific resistance of the sludge, so that the measurement time of the specific resistance of the whole sludge is greatly prolonged.
Sludge is often conditioned to promote dewatering during dewatering. The traditional chemical conditioner has small dosage (generally not exceeding 1% of the dry weight of the sludge), and does not influence the traditional detection indexes (such as specific resistance of the sludge and capillary water absorption time) to represent the dehydration performance. However, when physical conditioners (such as sawdust and fly ash) are used for conditioning, the dosage of the physical conditioners can reach 100% of the dry weight of the sludge, and the traditional detection indexes (particularly capillary water absorption time) cannot truly represent the dehydration performance of the conditioned sludge. In addition, when sludge particles are easily deformed (such as biochemical sludge), the sludge has high compressibility during mechanical dewatering, and therefore, it is also necessary to evaluate the compressibility of the sludge when investigating the dewatering performance of the sludge. The sludge dewatering process is divided into a sludge cake forming stage and a sludge cake compressing stage, and the specific sludge resistance data can only reflect the resistance of the sludge cake forming stage and cannot reflect the characteristics of the sludge compressing stage. The compression stage of the high-compressibility sludge is long, and the traditional system pushing the sludge interface with gas is likely to break the sludge cake before the compression stage is unstable, so that the high-compressibility sludge is difficult to use in the sludge compressibility experiment.
In conclusion, the traditional detection indexes (capillary water absorption time and sludge specific resistance) mainly aim at characterizing the water filtration performance of the sludge, the compression performance of the sludge is difficult to characterize, the measurement complexity and the detection time of the sludge specific resistance are long, and the rapid, effective and comprehensive evaluation on the sludge dehydration performance cannot be met.
Disclosure of Invention
In view of the above situation, in order to solve the defects of the prior art, the present invention aims to provide a device for measuring sludge dewatering performance and a method for using the same, which solve the problems of poor man-made repeatability, long detection time and incapability of simultaneously evaluating sludge compressibility in sludge specific resistance measurement and detection.
The technical scheme of the invention is as follows:
a sludge dewatering performance measuring device comprises a support (1), a dewatering device main body (2), a cylinder (3), a linear displacement sensor (4), a connector (5), a pressure sensor (6), a liquid storage tank (7), an electronic balance (8), an electromagnetic valve (9), an air compressor (10), a data acquisition system (11), a sludge adding valve (12) and an exhaust valve (13); the air cylinder (3) and the linear displacement sensor (4) are fixed on the upper layer of the support (1), a piston rod in the air cylinder (3) is connected with a measuring rod of the linear displacement sensor (4) through a connector (5), and the piston rod and the measuring rod are completely synchronous in the vertical direction; the dehydration device main body (2) is arranged at the middle layer of the bracket (1), and one end of a piston rod of the cylinder (3) is fixed on a piston (23) of the dehydration device main body (2); the electronic balance (8) is arranged right below the dehydration device main body (2), and the liquid storage tank (7) is arranged above the electronic balance (8) and is used for receiving filtrate discharged by the dehydration device main body (2); an inlet of the electromagnetic valve (9) is connected with the air compressor (10), two outlets of the electromagnetic valve are connected with the air cylinder (3), the pressure sensor (6) is arranged on a piston (23) of the dehydration device main body (2), and the mud adding valve (12) and the exhaust valve (12) are respectively connected with the piston (23) through pipelines; the communication lines of the pressure sensor (6), the electronic balance (8) and the electromagnetic valve (9) are connected with a data acquisition system (11).
The dehydration device main body (2) consists of an upper cylinder body (21) and a lower cylinder body (22), and a piston (23) is arranged in the upper cylinder body (21); the top of the upper cylinder body (21) is of a cylindrical structure, the bottom of the upper cylinder body is of a flange structure, and a first sealing gasket (25) is arranged on the bottom surface of the upper cylinder body (21); the top of the lower cylinder (22) is of a flange structure, is aligned with the bottom of the upper cylinder (21) and can be fastened by bolts, and the bottom of the lower cylinder (22) is of a funnel structure; a porous plate (24) is arranged in the lower cylinder body (22), the top surface of the porous plate (24) is flush with the top surface of the lower cylinder body (22), and a second sealing gasket (26) is arranged on the top surface of the lower cylinder body (22); the filtering material (27) can be single-layer filter paper or single-layer filter screen or upper filter paper and lower filter screen, and is placed between the first sealing gasket (25) and the second sealing gasket (26), and the diameter of the filtering material is larger than the inner diameter of the upper cylinder body (21) and smaller than the diameters of the first sealing gasket (25) and the second sealing gasket (26).
A first through hole (231), a second through hole (232) and a third through hole (233) are formed in the piston (23), wherein the first through hole (231) is connected with the pressure sensor (6), the second through hole (232) is communicated with the mud adding valve (12) through a pipeline, and the third through hole (233) is communicated with the exhaust valve (13) through a transparent pipeline; two seals (234) are provided between the piston (23) and the upper cylinder (21) to enable the piston (23) to remain vertically leak-free within the upper cylinder (21).
The electromagnetic valve (9) is of a three-position five-way type.
The data acquisition system (11) comprises a computer, a data acquisition card with a USB interface and a software program, the data acquisition system (11) can change the on-off state of the electromagnetic valve (9) through communication signals to realize the up-and-down movement of the air cylinder (3), and the filter liquor amount and the piston height position at different moments are respectively recorded by collecting the communication signals of the electronic balance (8) and the linear displacement sensor (4).
The use method of the sludge dewatering performance measuring device comprises the following steps:
1) starting an electronic balance (8), an air compressor (10) and a data acquisition system (11); opening a mud adding valve (12) and an exhaust valve (13);
2) the filter material (27) is well placed, and the upper cylinder (21) and the lower cylinder (22) of the dehydration device main body (2) are fastened by bolts;
3) opening a software program of a data acquisition system (11), setting the height position and pressure of a piston (23), operating the software program, recording the liquid amount in a liquid storage tank (7) and the height position of the piston (23) in real time by the data acquisition system (11) through an electronic balance (8) and a linear displacement sensor (4) respectively, moving a cylinder (3) by controlling an air solenoid valve (9), adjusting the piston (23) to a required position, adding sludge into an upper cylinder body (21) through a sludge adding valve (12) until sludge appears in a transparent pipeline connected with an exhaust valve (13), and quickly closing the sludge adding valve (12) and the exhaust valve (13);
4) the piston (23) is adjusted to move downwards through the electromagnetic valve (9), and the pressure is kept unchanged until a signal fed back by the pressure sensor (6) reaches a set pressure;
5) the sludge specific resistance measuring step adopts the steps (1) to (4), then a change signal along with time is obtained according to the filtrate amount fed back by the electronic balance (8), the endpoint of the filtering stage is judged based on the inflection point of a linear region appearing on the basis of the change amount (namely V-delta t/delta V, wherein V is the filtrate volume and the filtrate volume/filtrate density, and t is the time) of the filtrate amount to 1/filtrate amount to the time, the sludge Specific Resistance (SRF) is calculated according to the slope of the linear region and the filtrate amount of the endpoint of the filtering stage, and the calculation formula is that
Wherein: a-filtration area, P-pressure sensor reading (i.e. dewatering pressure), μ -filtrate viscosity, c-dry sludge weight per filtrate volume filtered (c ═ CV/V)fC-initial concentration of sludge, V-initial sludge volume in the dehydration unit, VfThe volume of filtrate corresponding to the end of the filtration phase), the slope of the K-linear region;
6) the sludge compressibility coefficient measuring step adopts at least three different pressures, the pressure is set from low to high, and the dehydration time under each pressure is not less than 1.5 h; the first press-dehydration step is the same as the above-mentioned steps (1) to (4) except for the initial setting of different pressures and dehydration times; after the last pressure dehydration is finished, directly pressurizing the mud cakes again to a set value by adopting the step (4); recording the height position of the piston (23) at the dehydration end point moment under different pressures; the sludge compression coefficient gamma is obtained by adopting least square fitting according to the following formula:
wherein: h is0-initial piston height after completion of sludge addition; h is a total ofiOr hj-piston height position at the ith or jth dewatering end time; piOr Pj-pressure at the i-th or j-th dehydration.
The invention has the beneficial effects that:
(1) the traditional SRF detection is usually measured by adopting a Buchner funnel under the negative pressure condition, and the water content of a filter cake at the end point needs to be measured, so that the manual operation is complicated and the measurement time is too long. The invention adopts a mechanical pressing and data acquisition system, so that the detection result is more consistent with the mechanical press-filtering dehydration condition, the filter liquor amount is recorded in real time in the detection process, and the self-detection process has higher automation degree. The method directly estimates the specific resistance of the sludge according to the inflection point of the linear region, does not need to measure the water content of the mud cake, and has short measuring process time and higher accuracy and repeatability.
(2) The device and the method provided by the invention can simultaneously measure the specific resistance and compressibility coefficient of the sludge under the condition of not replacing the sludge, simplify the measurement steps and realize the comprehensive evaluation of the sludge dewatering performance.
Drawings
FIG. 1 is a schematic view of a sludge dewatering performance measuring device
FIG. 2 is a schematic view of the main structure of the dewatering device
FIG. 3 is a schematic view showing the filtering curves V- Δ t/Δ V and the judgment of the end point of the filtering stage
FIG. 4 is a schematic view of measurement and calculation of specific resistance of sludge
FIG. 5 is a schematic view of measurement and calculation of compressibility coefficient of sludge
Detailed Description
The present invention will be described in further detail with reference to examples and drawings, but the present invention is not limited to these examples.
The first embodiment is as follows:
as shown in fig. 1 and 2, a sludge dewatering performance measuring device comprises a support (1), a dewatering device main body (2), a cylinder (3), a linear displacement sensor (4), a connector (5), a pressure sensor (6), a liquid storage tank (7), an electronic balance (8), an electromagnetic valve (9), an air compressor (10), a data acquisition system (11), a sludge adding valve (12) and an exhaust valve (13); the air cylinder (3) and the linear displacement sensor (4) are fixed on the upper layer of the support (1), a piston rod in the air cylinder (3) is connected with a measuring rod of the linear displacement sensor (4) through a connector (5), and the piston rod and the measuring rod are completely synchronous in the vertical direction; the dehydration device main body (2) is arranged at the middle layer of the bracket (1), and one end of a piston rod of the cylinder (3) is fixed on a piston (23) of the dehydration device main body (2); the electronic balance (8) is arranged right below the dehydration device main body (2), and the liquid storage tank (7) is arranged above the electronic balance (8) and is used for receiving filtrate discharged by the dehydration device main body (2); an inlet of the electromagnetic valve (9) is connected with the air compressor (10), two outlets of the electromagnetic valve are connected with the air cylinder (3), the pressure sensor (6) is arranged on a piston (23) of the dehydration device main body (2), and the mud adding valve (12) and the exhaust valve (12) are respectively connected with the piston (23) through pipelines; the communication lines of the pressure sensor (6), the electronic balance (8) and the electromagnetic valve (9) are connected with a data acquisition system (11).
As shown in figure 2, the dehydration device main body (2) is composed of an upper cylinder body (21) and a lower cylinder body (22), and a piston (23) is arranged in the upper cylinder body (21); the top of the upper cylinder body (21) is of a cylindrical structure, the bottom of the upper cylinder body is of a flange structure, and a first sealing gasket (25) is arranged on the bottom surface of the upper cylinder body (21); the top of the lower cylinder (22) is of a flange structure, is aligned with the bottom of the upper cylinder (21) and can be fastened by bolts, and the bottom of the lower cylinder (22) is of a funnel structure; a porous plate (24) is arranged in the lower cylinder body (22), the top surface of the porous plate (24) is flush with the top surface of the lower cylinder body (22), and a second sealing gasket (26) is arranged on the top surface of the lower cylinder body (22); the filtering material (27) can be an upper layer of filter paper and a lower layer of filter screen, is arranged between the first sealing gasket (25) and the second sealing gasket (26), and has a diameter larger than the inner diameter of the upper cylinder body (21) and smaller than the diameters of the first sealing gasket (25) and the second sealing gasket (26).
A first through hole (231), a second through hole (232) and a third through hole (233) are formed in the piston (23), wherein the first through hole (231) is connected with the pressure sensor (6), the second through hole (232) is communicated with the mud adding valve (12) through a pipeline, and the third through hole (233) is communicated with the exhaust valve (13) through a transparent pipeline; two seals (234) are provided between the piston (23) and the upper cylinder (21) to enable the piston (23) to remain vertically leak-free within the upper cylinder (21).
The electromagnetic valve (9) is of a three-position five-way type.
The data acquisition system (11) comprises a computer, a data acquisition card with a USB interface and a software program, the data acquisition system (11) can change the on-off of the electromagnetic valve (9) through communication signals to realize the up-and-down movement of the cylinder (3), and the filter liquor amount and the piston height position at different moments are respectively recorded by collecting the communication signals of the electronic balance (8) and the linear displacement sensor (4).
A use method of a sludge dewatering performance measuring device comprises the following steps:
1) starting an electronic balance (8), an air compressor (10) and a data acquisition system (11); opening a mud adding valve (12) and an exhaust valve (13);
2) the filter material (27) is well placed, and the upper cylinder (21) and the lower cylinder (22) of the dehydration device main body (2) are fastened by bolts;
3) opening a software program of a data acquisition system (11), setting the height position and pressure of a piston (23), operating the software program, recording the liquid amount in a liquid storage tank (7) and the height position of the piston (23) in real time by the data acquisition system (11) through an electronic balance (8) and a linear displacement sensor (4) respectively, moving a cylinder (3) by controlling an air solenoid valve (9), adjusting the piston (23) to a required position, adding sludge into an upper cylinder body (21) through a sludge adding valve (12) until sludge appears in a transparent pipeline connected with an exhaust valve (13), and quickly closing the sludge adding valve (12) and the exhaust valve (13);
4) the piston (23) is adjusted to move downwards through the electromagnetic valve (9) until a signal fed back by the pressure sensor (6) reaches a set pressure (such as 0.05MPa), and then the pressure is kept unchanged;
5) as shown in fig. 4, the sludge specific resistance measuring step adopts the above steps (1) - (4), then the filtrate amount fed back by the electronic balance (8) changes along with time according to the signal, and the filtering stage end point is judged based on the change of the filtrate volume to 1/filtrate volume versus time (i.e. V- Δ t/Δ V, where V is the filtrate volume/filtrate density, and since the solid content in the filtrate is very low, it is regarded as pure water, and the pure water density is used to replace the filtrate density for calculation, and t is time) to generate a linear region inflection point (see inflection point in the description of the specification, the inflection point is used for judging the filtering stage end point (see fig. 4)
FIG. 3), calculating the sludge Specific Resistance (SRF) from the slope of the linear zone and the amount of filtrate at the end of the filtration phase, the calculation formula being
Wherein: a-filtration area, P-pressure sensor reading (i.e. dewatering pressure), μ -filtrate viscosity, c-dry sludge weight per unit volume filtered (c ═ CV/V)fC-initial concentration of sludge, V-initial sludge volume in the dehydration unit, Vf-the filtrate volume corresponding to the end of the filtration phase), the slope of the K-linear region;
6) referring to fig. 5, the sludge compressibility factor measuring step uses at least three different pressures (e.g. 0.05, 0.25, 0.5MPa), the pressure is set from low to high, and the dewatering time is 1.5h at each pressure; the first press-dehydration step is the same as the above-mentioned steps (1) to (4) except for initially setting different pressures and dehydration times; after the last pressure dehydration is finished, mud does not need to be added again, and the mud cake is directly pressurized again to a set value in the step (4); recording the height position of the piston (23) at the dehydration end point moment under different pressures; the sludge compression coefficient gamma is obtained by adopting a least square method according to the following formula:
wherein: h is0-initial piston height after completion of sludge addition; h isiOr hj-piston height position at the ith or jth dewatering end time; piOr Pj-pressure at the i-th or j-th dehydration.
Example two:
the second embodiment is substantially the same as the first embodiment, and the main difference is that: after the specific resistance of the sludge is measured (namely, the inflection point of a linear region appears at V-delta t/delta V), the dehydration time is still waited for 1.5h, the height position of the piston (23) at the end time of the first dehydration is recorded, then according to the sludge compressibility coefficient measuring step, the step (4) is adopted for direct pressurized dehydration, and the height position of the piston (23) at the end time of the dehydration under different pressures is recorded, so that the specific resistance of the sludge and the sludge compressibility coefficient can be measured simultaneously under the condition of not replacing the sludge.
Claims (6)
1. The utility model provides a sludge dewatering performance measuring device which characterized in that: the device comprises a bracket, a dehydration device main body, an air cylinder, a linear displacement sensor, a connector, a pressure sensor, a liquid storage tank, an electronic balance, an electromagnetic valve, an air compressor, a data acquisition system, a mud adding valve and an exhaust valve; the air cylinder and the linear displacement sensor are fixed on the upper layer of the bracket, and a piston rod in the air cylinder is connected with a measuring rod of the linear displacement sensor by adopting a connector, so that the piston rod and the measuring rod are completely synchronous in the vertical direction; the dehydration device main body is arranged on the middle layer of the bracket, and one end of a piston rod of the air cylinder is fixed on a piston of the dehydration device main body; the electronic balance is horizontally placed under the dehydration device main body, and the liquid storage tank is placed above the electronic balance and used for receiving filtrate discharged by the dehydration device main body; the inlet of the electromagnetic valve is connected with an air compressor, two outlets of the electromagnetic valve are connected with a cylinder, the pressure sensor is arranged on a piston of the dehydration device main body, and the mud adding valve and the exhaust valve are respectively connected with the piston through pipelines; and the communication lines of the pressure sensor, the electronic balance and the electromagnetic valve are connected with a data acquisition system.
2. The apparatus of claim 1, wherein the main body of the dewatering apparatus comprises an upper cylinder and a lower cylinder, and the upper cylinder has a piston therein; the top of the upper cylinder body is of a cylinder structure, the bottom of the upper cylinder body is of a flange structure, and a first sealing gasket is arranged on the bottom surface of the upper cylinder body; the top of the lower cylinder body is of a flange structure, is aligned with the bottom of the upper cylinder body and can be fastened by adopting bolts, and the bottom of the lower cylinder body is of a funnel structure; a porous plate is arranged in the lower cylinder body, the top surface of the porous plate is flush with the top surface of the lower cylinder body, and a second sealing gasket is arranged on the top surface of the lower cylinder body; the filtering material can adopt single-layer filter paper or single-layer filter screen or upper filter paper lower filter screen, is placed between the first sealing gasket and the second sealing gasket, and the diameter of the filtering material is larger than the inner diameter of the upper cylinder body and smaller than the diameters of the first sealing gasket and the second sealing gasket.
3. The sludge dewatering performance measuring device according to claim 1, wherein the piston is provided with a first through hole, a second through hole and a third through hole, wherein the first through hole is connected with the pressure sensor, the second through hole is communicated with the mud adding valve through a pipeline, and the third through hole is communicated with the exhaust valve through a transparent pipeline; two seals are provided between the piston and the upper cylinder to enable the piston to remain vertically leak-free within the upper cylinder.
4. The apparatus according to claim 1, wherein the solenoid valve is of a three-position five-way type.
5. The device for measuring the sludge dewatering performance according to claim 1, wherein the data acquisition system comprises a computer, a data acquisition card with a USB interface and a software program, the data acquisition system can change the on-off of the electromagnetic valve through a communication signal to realize the up-and-down movement of the air cylinder, and the filter liquid amount and the piston height position at different moments are respectively recorded by collecting the communication signals of the electronic level and the linear displacement sensor.
6. The use method of the sludge dewatering performance measuring device according to claims 1-5 is characterized by comprising the following steps:
1) starting the electronic balance, the air compressor and the data acquisition system; opening a mud adding valve and an exhaust valve;
2) placing the filter material, and fastening an upper cylinder and a lower cylinder of the main body of the dehydration device by bolts;
3) opening a software program of a data acquisition system, setting the height position and pressure of a piston, operating the software program, recording the liquid amount and the height position of the piston in a liquid storage tank in real time by the data acquisition system through an electronic level and a linear displacement sensor respectively, moving an air cylinder by controlling an air solenoid valve, adjusting the piston to a required position, adding sludge into an upper cylinder body through a sludge adding valve until sludge appears in a transparent pipeline connected with an exhaust valve, and quickly closing the sludge adding valve and the exhaust valve;
4) the piston is adjusted to move downwards through the electromagnetic valve until the signal fed back by the pressure sensor reaches the set pressure, and then the pressure is kept unchanged;
5) the sludge specific resistance measuring step adopts the steps (1) to (4), then a signal is changed along with time according to the filtrate amount fed back by an electronic balance, the end point of the filtering stage is judged based on the inflection point of a linear region appearing on the basis of the volume of the filtrate-1/the volume of the filtrate-time variation (namely V-delta t/delta V, wherein V is the filtrate volume and the filtrate amount/filtrate density, and t is the time), the sludge Specific Resistance (SRF) is calculated according to the slope of the linear region and the filtrate amount of the end point of the filtering stage, and the calculation formula is
Wherein: a-filtration area, P-pressure sensor reading (i.e. dewatering pressure), μ -filtrate viscosity, c-dry sludge weight per filtrate volume filtered (c ═ CV/V)fC-initial concentration of sludge, V-initial sludge volume in the dehydration unit, Vf-the filtrate volume corresponding to the end of the filtration phase), the slope of the K-linear region;
6) the sludge compressibility coefficient measuring step adopts at least three different pressures, the pressure is set from low to high, and the dehydration time under each pressure is not less than 1.5 h; the first press-dehydration step is the same as the above-mentioned steps (1) to (4) except for initially setting different pressures and dehydration times; after the last pressure dehydration is finished, directly pressurizing the mud cakes again to a set value by adopting the step (4); recording the height position of the piston at the dehydration end point moment under different pressures; the sludge compression coefficient gamma is obtained by adopting least square fitting according to the following formula:
wherein: h is0-initial piston height after completion of sludge addition; h is a total ofiOr hj-piston height position at the ith or jth dewatering end time; piOr Pj-pressure at the i-th or j-th dehydration.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210174409.XA CN114544421B (en) | 2022-02-25 | 2022-02-25 | Sludge dewatering performance measuring device and using method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210174409.XA CN114544421B (en) | 2022-02-25 | 2022-02-25 | Sludge dewatering performance measuring device and using method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114544421A true CN114544421A (en) | 2022-05-27 |
| CN114544421B CN114544421B (en) | 2024-03-12 |
Family
ID=81679386
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210174409.XA Active CN114544421B (en) | 2022-02-25 | 2022-02-25 | Sludge dewatering performance measuring device and using method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114544421B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115015527A (en) * | 2022-06-10 | 2022-09-06 | 山东理工大学 | Experimental device and experimental method for simulating high pressure of deep cone thickener |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102721787A (en) * | 2011-03-30 | 2012-10-10 | 同济大学 | Organic garbage compression dehydration performance detection device |
| CN105973747A (en) * | 2016-05-31 | 2016-09-28 | 安徽理工大学 | Filter pressing type sludge specific resistance measuring device |
| CN206906179U (en) * | 2017-05-22 | 2018-01-19 | 合肥工业大学 | A kind of vapour-pressure type sludge specific resistance measurement device |
| CN108776155A (en) * | 2018-07-13 | 2018-11-09 | 天津科技大学 | A kind of conductance type sludge specific resistance measuring device |
| CN109374862A (en) * | 2018-11-27 | 2019-02-22 | 中国科学院武汉岩土力学研究所 | A kind of mud high-pressure filteration compression dehydration test cavity and test device |
| CN111175172A (en) * | 2018-11-09 | 2020-05-19 | 中国市政工程中南设计研究总院有限公司 | Device for measuring specific resistance parameter of sludge, use method and application thereof |
| CN210834549U (en) * | 2019-10-28 | 2020-06-23 | 河北大学 | Multi-connected automatic sludge specific resistance measuring device |
| CN111423087A (en) * | 2020-03-20 | 2020-07-17 | 河海大学 | Sludge dewatering machine for teaching and teaching use method |
| CN113946142A (en) * | 2021-06-19 | 2022-01-18 | 河南中夏环保科技有限公司 | Automatic control treatment method for sludge dewatering process of sewage water of tap water plant |
-
2022
- 2022-02-25 CN CN202210174409.XA patent/CN114544421B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102721787A (en) * | 2011-03-30 | 2012-10-10 | 同济大学 | Organic garbage compression dehydration performance detection device |
| CN105973747A (en) * | 2016-05-31 | 2016-09-28 | 安徽理工大学 | Filter pressing type sludge specific resistance measuring device |
| CN206906179U (en) * | 2017-05-22 | 2018-01-19 | 合肥工业大学 | A kind of vapour-pressure type sludge specific resistance measurement device |
| CN108776155A (en) * | 2018-07-13 | 2018-11-09 | 天津科技大学 | A kind of conductance type sludge specific resistance measuring device |
| CN111175172A (en) * | 2018-11-09 | 2020-05-19 | 中国市政工程中南设计研究总院有限公司 | Device for measuring specific resistance parameter of sludge, use method and application thereof |
| CN109374862A (en) * | 2018-11-27 | 2019-02-22 | 中国科学院武汉岩土力学研究所 | A kind of mud high-pressure filteration compression dehydration test cavity and test device |
| CN210834549U (en) * | 2019-10-28 | 2020-06-23 | 河北大学 | Multi-connected automatic sludge specific resistance measuring device |
| CN111423087A (en) * | 2020-03-20 | 2020-07-17 | 河海大学 | Sludge dewatering machine for teaching and teaching use method |
| CN113946142A (en) * | 2021-06-19 | 2022-01-18 | 河南中夏环保科技有限公司 | Automatic control treatment method for sludge dewatering process of sewage water of tap water plant |
Non-Patent Citations (2)
| Title |
|---|
| 赵培涛;葛仕福;黄瑛;陈振乾;李响;: "压滤式污泥过滤比阻测定方法", 东南大学学报(自然科学版), no. 01, pages 157 - 168 * |
| 黄祖舜;: "污泥机械脱水――加压过滤的设计计算", 工业用水与废水, no. 03 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115015527A (en) * | 2022-06-10 | 2022-09-06 | 山东理工大学 | Experimental device and experimental method for simulating high pressure of deep cone thickener |
| CN115015527B (en) * | 2022-06-10 | 2023-12-22 | 山东理工大学 | Experimental device and experimental method for simulating high pressure of deep cone thickener |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114544421B (en) | 2024-03-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN114544421B (en) | Sludge dewatering performance measuring device and using method | |
| Christensen et al. | Specific resistance measurements: nonparabolic data | |
| CN206906179U (en) | A kind of vapour-pressure type sludge specific resistance measurement device | |
| CN100439895C (en) | Oil elastic modulus detector based on volume elastic modulus definition | |
| CN2804850Y (en) | Instrument for testing thickness of foam drilling fluid | |
| CN116481859B (en) | Water quality sampling detection device and detection method | |
| CN100559181C (en) | The online test method of chain cloth performance and device | |
| CN203224427U (en) | Coarse-grained soil permeability coefficient measuring device | |
| CN211374665U (en) | Sludge dewatering performance testing device | |
| CN113552037A (en) | Device and method for testing dual-porosity seepage parameters of garbage | |
| CN204964356U (en) | Rubbish soil subsides test device | |
| Kapur et al. | Modeling of the consolidation stage in pressure filtration of compressible cakes | |
| CN206330859U (en) | Filter-press type sludge specific resistance test device | |
| Oolman et al. | Filtration properties of mycelial microbial broths | |
| CN108776155A (en) | A kind of conductance type sludge specific resistance measuring device | |
| CN202041527U (en) | Online monitoring device for pollution degree of lubricating oil | |
| CN111965006B (en) | Shale granule strength tester and testing method thereof | |
| CN209841859U (en) | Mud high pressure filtration compression dehydration test cavity and testing arrangement | |
| CN211452497U (en) | Automatic measuring device for drilling fluid filtration loss | |
| Dick et al. | Sludge dewatering | |
| CN211553692U (en) | Porosity measuring device for porous medium | |
| CN210834549U (en) | Multi-connected automatic sludge specific resistance measuring device | |
| Wiedemann et al. | Experimental investigation of the shrinkage and cracking behaviour of fine participate filter cakes | |
| CN102147404A (en) | Online monitoring method and device of pollution degree of lubricant | |
| CN2311770Y (en) | Gas phase micro moisture measuring device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |