Device and method for filtering and discharging filter residues

Abstract

The invention belongs to the technical field of filter residue treatment, and relates to a device and a method for filtering and discharging filter residues, the device comprises two-stage series negative pressure filters of a first-stage filter and a second-stage filter, a clear liquid temporary storage tank and a residue barrel; the aperture of the filter element of the first-stage filter is larger than the actual filter residue filtering requirement, and the aperture of the filter element of the second-stage filter is matched with the actual filter residue filtering requirement; a clear liquid outlet of the second-stage filter is connected with a clear liquid temporary storage tank; a slag outlet of the first-stage filter and a slag outlet of the second-stage filter are connected with a slag barrel, and a slag outlet of the slag barrel is connected with a vacuum conveying pipeline and used for conveying filter residues to subsequent procedures in a vacuum mode; and the first-stage filter and the second-stage filter are provided with jackets or electric heaters for drying filter residues in the filters. According to the invention, filter residues and dry residues are discharged after filtration, and the defects that the water content of discharged residues is high, wet residues are difficult to transfer and treat, residues and mud are easy to scatter on the ground, the equipment structure is complex, and equipment faults are easy to occur in traditional filtering equipment are effectively overcome.

Description

Technical Field

[0001] The invention belongs to the technical field of filter residue treatment, and in particular relates to a device and method for filter residue filtering and discharge. Background Art

[0002] The nuclear fuel manufacturing industry currently uses flat filters, centrifuges, filter presses and other equipment to filter solid particles in slurry to form filter cakes, and manually or automatically discharge the residue. Whether it is a centrifuge or a filter press, the discharged residue has a high water content, which is not conducive to the subsequent transfer and treatment of the residue. At the same time, the equipment structure is complex and the maintenance requirements of the equipment are high. If the equipment is not properly maintained, it is easy to cause bearing wear or hydraulic mechanism oil leakage and other faults.

[0003] Therefore, it is urgent to develop a device and method for filtering and discharging residues to solve the above-mentioned technical problems existing in traditional filtering equipment. Summary of the invention

[0004] The object of the present invention is to provide a device and method for filtering and discharging filter residue, which realizes the discharge of dry filter residue after filtration, and can effectively solve the defects of traditional filtering equipment such as high moisture content of the filter residue, difficulty in transferring and processing wet residue, easy spillage of residue mud on the ground, complex equipment structure and easy equipment failure.

[0005] The technical solution to achieve the purpose of the present invention is:

[0006] A device for filtering and discharging filter residue, the device comprising: a first-stage filter and a second-stage filter, two-stage series-connected negative pressure filters, a clear liquid temporary storage tank, and a residue bucket; the filter element pore size of the first-stage filter is larger than the actual filtering requirement of the filter residue, and the filter element pore size of the second-stage filter matches the actual filtering requirement of the filter residue; the clear liquid outlet of the second-stage filter is connected to the clear liquid temporary storage tank; the residue outlets of the first-stage filter and the second-stage filter are both connected to the residue bucket, and the residue outlet of the residue bucket is connected to a vacuum conveying pipeline for vacuum conveying the filter residue to a subsequent process; the first-stage filter and the second-stage filter are both provided with a jacket or an electric heater for drying the filter residue in the filter.

[0007] Furthermore, the top cover of the clear liquid temporary storage tank is connected to a vacuum pump.

[0008] Furthermore, the jacket is provided with a water inlet and a water outlet, and hot water is introduced into the jacket through the water inlet and the water outlet.

[0009] Furthermore, the first-stage filter is a scraper filter, and the second-stage filter is a candle filter.

[0010] Furthermore, a valve is provided between the clear liquid temporary storage tank and the vacuum pump; the liquid inlet and the clear liquid outlet of the scraper-type filter are respectively provided with valves, the liquid inlet and the clear liquid outlet of the candle-type filter are respectively provided with valves, and the liquid inlet of the clear liquid temporary storage tank is provided with a liquid inlet valve; a slag discharge bottom valve is provided at the bottom of the scraper-type filter, and a slag discharge bottom valve is provided at the bottom of the candle-type filter; a slag discharge back-blowing compressed air valve is provided at the top of the candle-type filter; and valves are provided at the exhaust gas outlet of the scraper-type filter and the exhaust gas outlet of the candle-type filter.

[0011] A method for filtering and discharging filter residues, the method comprising:

[0012] Step 1, vacuumizing the clear liquid temporary storage tank;

[0013] Step 2, the residue-liquid mixture is filtered in two stages, and the filtrate is stored in a clear liquid temporary storage tank;

[0014] Step 3, drying the filter residue in the two-stage filter;

[0015] Step 4, the filter residue in the two-stage filter is discharged into the residue bucket;

[0016] Step 5: The filtered residue in the residue barrel is vacuum transported to the subsequent process.

[0017] Furthermore, in step 1, the clear liquid temporary storage tank is pumped to about -20 kPa.

[0018] Furthermore, in step 3, hot water at 100° C. is introduced into the jackets of the scraper filter and the candle filter to heat and dry the filter residue in the filter. While heating, the inlet and outlet liquid valves of the filter are used to utilize the negative pressure of the clear liquid storage tank to extract the residual liquid and tail gas from the filter; when the water content of the filter residue is reduced to below 10%, the inlet and outlet liquid valves of the scraper filter and the candle filter are closed.

[0019] Furthermore, when the filter residue in the scraper filter is discharged in step 4, the scraper of the scraper filter is started, the bottom valve of the scraper filter is opened, and the filter residue is discharged into the slag bucket; when the filter residue in the candle filter is discharged, the bottom valve and tail gas valve of the candle filter are opened, and the compressed air valve for back-blowing the filter residue is opened, and the filter residue is blown into the slag bucket by compressed air.

[0020] The beneficial technical effects of the present invention are:

[0021] 1. The present invention provides a residue filtering and slag discharge device, which adopts a two-stage series negative pressure filtration process. The filter element pore size of the first-stage filter is appropriately larger, and the filter element pore size of the second-stage filter matches the actual filtration requirements. By selecting filter elements with different pore sizes, the sludge processing capacity of the two-stage filters is controlled.

[0022] 2. In a residue filtering and residue discharging device provided by the present invention, a scraper filter is used for the first stage filtration and a candle filter is used for the second stage filtration. Both filters are provided with a jacket or electric heating. Hot water can be introduced into the jacket or electric heating can be turned on to dry the residue in the filter.

[0023] 3. The present invention provides a device and method for filtering and discharging filter residues, which realizes the discharge of dry filter residues after filtration. After discharge, the dry residues are easy to be transported by vacuum conveyor or belt conveyor, which is convenient for realizing the automation, dust-free and cleanliness of the subsequent transportation and processing of the filter residues.

[0024] 4. The device and method for filtering and discharging filter residues provided by the present invention effectively solve the problems of high water content of filter residues in traditional filtering methods, easy spillage during the transportation of filter residues, and environmental pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The present invention provides a schematic diagram of a residue filtering and residue discharging device. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0027] like Figure 1 As shown, a device for filtering and discharging filter residues provided by the present invention comprises: a first-stage filter and a second-stage filter, two-stage series-connected negative pressure filters, a clear liquid temporary storage tank, and a slag bucket; the filter element pore size of the first-stage filter is larger than the actual filtering requirement of the filter residue, and the filter element pore size of the second-stage filter matches the actual filtering requirement of the filter residue; the clear liquid outlet of the second-stage filter is connected to the clear liquid temporary storage tank, and the top cover of the clear liquid temporary storage tank is connected to a vacuum pump; the slag outlets of the first-stage filter and the second-stage filter are both connected to the slag bucket, and the slag outlets of the slag bucket are connected to a vacuum conveying pipeline for vacuum conveying the filter residue to subsequent processes; the first-stage filter and the second-stage filter are both provided with a jacket or an electric heater for drying the filter residue in the filter.

[0028] In a specific embodiment, the first-stage filter is a scraper filter, and the second-stage filter is a candle filter.

[0029] In another specific embodiment, the residue-liquid mixture to be filtered is connected to the liquid inlet of the automatic scraper filter through a pipeline, the clear liquid outlet of the scraper filter is connected to the liquid inlet of the candle filter through a pipeline, and the clear liquid outlet of the candle filter is connected to the clear liquid temporary storage tank, wherein the top cover of the clear liquid temporary storage tank is connected to the vacuum pump through a pipeline. The scraper filter and the candle filter are both equipped with a jacket or an electric heater, and hot water can be passed into the jacket to heat the inside of the filter, or the electric heater can be directly used to heat the inside of the filter.

[0030] In another specific embodiment, the jacket is provided with a water inlet and a water outlet, and hot water is introduced into the jacket through the water inlet and the water outlet.

[0031] In another specific embodiment, a valve is provided between the clear liquid temporary storage tank and the vacuum pump; the liquid inlet and the clear liquid outlet of the scraper-type filter are respectively provided with valves, the liquid inlet and the clear liquid outlet of the candle-type filter are respectively provided with valves, and the liquid inlet of the clear liquid temporary storage tank is provided with a liquid inlet valve; a slag discharge bottom valve is provided at the bottom of the scraper-type filter, and a slag discharge bottom valve is provided at the bottom of the candle-type filter; a slag discharge back-blowing compressed air valve is provided at the top of the candle-type filter; and valves are provided at the exhaust gas outlet of the scraper-type filter and the exhaust gas outlet of the candle-type filter.

[0032] The present invention provides a method for filtering and discharging filter residues, which specifically comprises the following steps:

[0033] Step 1: Vacuum the clear liquid storage tank

[0034] Open the valve between the clear liquid temporary storage tank and the vacuum pump, and close other valves in the clear liquid temporary storage tank; turn on the vacuum pump and pump the clear liquid temporary storage tank to about -20kPa;

[0035] Step 2: The residue-liquid mixture is filtered in two stages, and the filtrate is stored in a clear liquid temporary storage tank.

[0036] Open the inlet and outlet valves of the scraper filter and candle filter and the inlet valve of the clear liquid temporary storage tank, filter the residue-liquid mixture in two stages, and store the filtrate in the clear liquid temporary storage tank; after the filtration is completed, close the vacuum pump and the inlet and outlet valves of the scraper filter and candle filter;

[0037] Step 3: Drying the residue in the two-stage filter

[0038] During drying, hot water at 100°C is introduced into the jackets of scraper filters and candle filters, and the filters are continuously heated by heat sources to dry the filter residues. While heating, the residual liquid and tail gas of the filter are extracted by the negative pressure of the clear liquid storage tank through the inlet and outlet valves of the filter. After long-term heating, the water content of the sludge is reduced to less than 10%, and the inlet and outlet valves of the scraper filters and candle filters are closed.

[0039] Step 4: Discharge the residue from the two-stage filter into the residue bucket

[0040] Start the scraper of the scraper filter, open the scraper filter slag discharge bottom valve, and discharge the filter residue into the slag bucket; open the candle filter slag discharge bottom valve and tail gas valve, open the candle filter slag discharge back-blow compressed air valve, and use compressed air to blow the filter residue into the slag bucket;

[0041] Step 5: Vacuum the filter residue in the slag bucket to the subsequent process

[0042] The slag barrel at the bottom of the scraper filter and candle filter is provided with a slag outlet and an air supply port. The slag outlet is connected to a vacuum conveying pipeline, which can vacuum convey the slag, powder or particles to the subsequent slag sludge incineration process.

[0043] The present invention is described in detail above with reference to the accompanying drawings and embodiments, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of ordinary technicians in the field without departing from the purpose of the present invention. The contents not described in detail in the present invention can adopt the existing technology.

Claims

1. A device for filtering and discharging residue, characterized in that: The device comprises: a first-stage filter and a second-stage filter, two-stage negative pressure filters connected in series, a clear liquid temporary storage tank, and a slag bucket; the filter element aperture of the first-stage filter is larger than the actual filtering requirement of the filter residue, and the filter element aperture of the second-stage filter matches the actual filtering requirement of the filter residue; the clear liquid outlet of the second-stage filter is connected to the clear liquid temporary storage tank; the slag outlets of the first-stage filter and the second-stage filter are both connected to the slag bucket, and the slag outlet of the slag bucket is connected to a vacuum conveying pipeline for vacuum conveying the filter residue to subsequent processes; the first-stage filter and the second-stage filter are both provided with a jacket or an electric heater for drying the filter residue in the filter.

2. The device for filtering and discharging residue according to claim 1, characterized in that: The top cover of the clear liquid temporary storage tank is connected with a vacuum pump.

3. The device for filtering and discharging residue according to claim 1, characterized in that: The jacket is provided with a water inlet and a water outlet, and hot water is introduced into the jacket through the water inlet and the water outlet.

4. The device for filtering and discharging residue according to claim 1, characterized in that: The first-stage filter is a scraper filter, and the second-stage filter is a candle filter.

5. The device for filtering and discharging residue according to claim 4, characterized in that: A valve is provided between the clear liquid temporary storage tank and the vacuum pump; the liquid inlet and the clear liquid outlet of the scraper-type filter are respectively provided with valves, the liquid inlet and the clear liquid outlet of the candle-type filter are respectively provided with valves, and the liquid inlet of the clear liquid temporary storage tank is provided with a liquid inlet valve; a slag discharge bottom valve is provided at the bottom of the scraper-type filter, and a slag discharge bottom valve is provided at the bottom of the candle-type filter; a slag discharge back-blowing compressed air valve is provided at the top of the candle-type filter; valves are provided at the tail gas outlet of the scraper-type filter and the tail gas outlet of the candle-type filter.

6. A method for filtering and discharging residue, characterized in that: The method comprises: Step 1, vacuumizing the clear liquid temporary storage tank; Step 2, the residue-liquid mixture is filtered in two stages, and the filtrate is stored in a clear liquid temporary storage tank; Step 3, drying the filter residue in the two-stage filter; Step 4, the filter residue in the two-stage filter is discharged into the residue bucket; Step 5: The filtered residue in the residue barrel is vacuum transported to the subsequent process.

7. The method for filtering and discharging residue according to claim 6, characterized in that: In the step 1, the clear liquid temporary storage tank is pumped to about -20 kPa.

8. The method for filtering and discharging residue according to claim 6, characterized in that: In the step 3, hot water at 100° C. is introduced into the jackets of the scraper filter and the candle filter to heat and dry the filter residue in the filter. While heating, the inlet and outlet valves of the filter are used to extract the residual liquid and tail gas from the filter using the negative pressure of the clear liquid storage tank; when the water content of the filter residue is reduced to below 10%, the inlet and outlet valves of the scraper filter and the candle filter are closed.

9. The method for filtering and discharging residue according to claim 6, characterized in that: When the filter residue in the scraper filter is discharged in the step 4, the scraper of the scraper filter is started, the bottom valve of the scraper filter is opened, and the filter residue is discharged into the slag bucket; when the filter residue in the candle filter is discharged, the bottom valve and tail gas valve of the candle filter are opened, and the compressed air valve for back-blowing the filter residue is opened to blow the filter residue into the slag bucket by compressed air.

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