WO2008134913A1 - Sludge screw vacuum hydroextractor - Google Patents

Abstract

A sludge screw vacuum hydroextractor comprises a dewateπng device and a feeding device for the dewateπng device The dewatering device comprises a dewatering drum (300) and a combined screw rod provided therein A right hand screw thread conveying member (20) and a left hand screw thread conveying member (22) are provided in the combined screw rod m an alternating arrangement, and a back pressure plate (21 ) is provided in the combined screw rod, provided with a hole (211) for sludge through therein A drain hole (24) is provided in the drum wall, and a vacuum suction device (13) is provided at the drain hole In addition, a heater (14) isprovided in the lydroextractor for heating the sludge The hydroextractor is used for secondly dewateπng the sludge with about 80% water ratio, finally to attain to the sludge within 40% water ratio

Description

 Instruction manual

Sludge spiral vacuum dehydrator

 The invention relates to an environmental protection treatment device for sludge. Specifically, it relates to a device for achieving spiral vacuum dehydration of sludge having a moisture content of about 80%. technical background

 With the increasing population of urban sewage network services, increasingly strict water quality standards, and the construction or expansion of large and medium-sized sewage treatment plants in cities, the production of sludge has also increased rapidly. In the case of China, sludge production will reach 17 million tons per year by 2015, which is more than twice the amount in 2003. If the sludge is not properly disposed and disposed of, it will cause serious secondary pollution. Therefore, how to reduce, efficiently, scientifically and harmlessly treat sludge has become a major problem faced by all countries in the world. At present, the sludge concentration and dewatering equipment selected by the major sewage treatment plants are basically: horizontal centrifugal dewatering machine, belt pressure filter dewatering machine, plate and frame filter dewatering machine. Among them, the "horizontal spiral centrifugal dewatering machine" is the most advanced sludge concentration and dewatering equipment in the world, but the water content of the final sludge after concentration and dewatering in actual operation is still 75%-80%. It is precisely because the sludge after concentrated dewatering still contains relatively high moisture, which brings great difficulties to subsequent sludge disposal. At present, there are still no innovative treatment and disposal processes in countries around the world, mainly focusing on the direct use of two technologies, such as fluidized bed incineration or vertical kiln incineration. The vulcanized bed is large in volume, high in energy consumption and high in pollution, so the traditional vulcanized bed incineration technology will be phased out. Although the vertical kiln incineration technology is more advanced than the vulcanized bed incineration technology, the volume is small, the sludge moisture content after incineration is very low, and the sludge treatment is basically completed, but it still faces the problem of high energy consumption, which cannot achieve high efficiency, low energy consumption, and reduction. Quantify the purpose of sludge treatment. Summary of the invention

The technical problem to be solved by the present invention is to provide a water retention rate in view of the deficiencies of the prior art. About 80% of the sludge is subjected to secondary dewatering sludge spiral vacuum dewatering machine to make up for the shortage of existing concentrated dewatering equipment, bringing high efficiency, low energy consumption and low pollution process changes for subsequent sludge treatment and disposal. . To this end, the present invention employs the following technical solutions: It includes a dewatering device and a sludge feeding device for the dewatering device; the dewatering device includes a dewatering barrel and a combined screw disposed in the barrel, the combined screw including a mandrel and a detachable threaded member and a reverse threaded member alternately arranged outside the mandrel, wherein the combined screw is further provided with a back pressure plate, and the back pressure plate is provided with a hole for the sludge to pass through The barrel wall is provided with a water outlet hole, and the spiral vacuum dehydrator is provided with a vacuum water suction device at the corresponding dewatering hole; the vacuum dewatering unit is further provided with a heating device for the sludge in the dewatering device. By using the technical solution of the present invention, the sludge having a water content of about 80% can be subjected to secondary dehydration with low energy consumption and high efficiency, and finally the target of the sludge moisture content within 40% can be achieved. It also brings revolutionary process changes with high efficiency, low energy consumption and low pollution for the subsequent treatment and disposal of sludge. When the sludge with a water content of 40% or less is used in the vertical kiln incineration technology, the energy consumption will be greatly reduced. If the sludge with a water content of less than 40% is directly granulated and used as a raw material for combustion in power plants and cement plants, it will be a measure of both economic and social benefits. DRAWINGS

 1 is a general schematic diagram of an embodiment of the present invention.

 2 is a schematic exploded view of a combined screw according to an embodiment of the present invention.

 3 is a perspective view of a back pressure plate in accordance with an embodiment of the present invention.

 4 is a schematic view of a sludge forced feeding device according to an embodiment of the present invention.

 Figure 5 is an enlarged cross-sectional view taken along line B of Figure 4 .

 Figure 6 is a partial schematic view of the barrel of the embodiment of the present invention.

 Figure 7 is a schematic view of the parts surrounding the water outlet forming a vacuum chamber.

 Figure 8 is a cross-sectional view of the barrel A-A.

 Figure 9 is an exploded view of the filter assembly inserted in the water outlet.

Fig. 10 is a view taken along line C of Fig. 9. detailed description Refer to the attached drawings. The invention comprises a dewatering device and a sludge forced feeding device of the dewatering device; the dewatering device comprises a dewatering barrel 300 and a combined screw disposed in the barrel, the combined screw comprising a mandrel and being detachably worn a forward conveying screw element 20 and a reverse threading element 22 which are alternately arranged outside the mandrel, and the combined screw is further provided with a back pressure plate 21, and the back pressure plate is provided with a hole 211 through which the sludge passes; The barrel wall is provided with a water outlet hole 24, and the vacuum dewatering machine is provided with a vacuum water suction device at the corresponding dewatering hole; the vacuum dewatering machine is further provided with a heating device for the sludge in the dewatering device.

 The sludge forced feeding device can be connected to the dewatering barrel and can ensure that the sludge is delivered to the dewatering barrel with a certain pressure. In the present embodiment, the forced feeding system uses a simple structure: it includes a hopper, the upper portion of the hopper is a cone 4, and the lower portion is a cylinder 5, and the cylindrical hopper is connected to the lower end of the cone hopper. The hopper center is provided with a feeding screw through a fixing bracket. 6. The screw in the cone body is further provided with a large blade for cutting 7. The outer periphery of the thread of the feeding screw is close to the wall of the cylindrical hopper. The feeding blade is designed with a large lead. Generally, the outer circumference of the thread of the feeding screw and the single side of the cylindrical hopper wall are kept between 0.3 mm and 0.8 mm. The blanking large blade 7 can be installed on the feeding screw in an angle-adjustable manner, so that it can be adjusted according to different sludges to improve the conveying treatment efficiency.

 The upper end of the center feeding screw is connected to the variable frequency motor 10 through the thrust pack 9 and the upper and lower flanges 8, and the lower end is kept at a small distance from the first large-diameter conveying screw element 20 of the extrusion screw in the inlet port 11 of the dehydrating barrel. .

 The variable frequency motor 10 drives the center feeding screw 6 to rotate, which drives the rotation of the rotating blade 7, and generates a pressing force to force the sludge into the barrel. The reaction force generated during the pressing process is absorbed by the thrust pack 9 in the middle of the upper and lower flanges 8. The outer periphery of the thread of the feed screw maintains a small gap with the wall of the hopper during operation to prevent run-up during feeding. The entire feed body is connected to the barrel where the feed port 11 is located through the lower end of the cylindrical hopper 5.

The combined screw can be a full rod type with all threads on its surface. In this embodiment, a more reasonable and optimized structure is used. The combined screw includes a mandrel and a threaded member that can be arbitrarily removed and combined outside the mandrel. Further, the mandrel is sleeved with a plurality of threaded elements, the threaded element comprising a threaded element having a forward conveying thread and a threaded element having a reversed thread. In this way, different types of threaded components can be made. In actual production, depending on the sludge to be treated, flexible combination can be made. High processing efficiency and guaranteed dewatering effect.

 As shown, the center of the screw is an integral mandrel 19 with splines engraved on the mandrel 19. The threaded element includes a forward feed threaded element 20 and a reverse threaded element 22. The back pressure plate 21 has an annular shape. One end of the mandrel 19 is connected to the transmission case 3, and the forward conveying screw element 20 and the reverse threading element 22 are alternately sleeved on the mandrel 19 and combined with the back pressure plate to form an adjustable combined screw, and the front end clamping cap 23 is used. locking. The surface of the back pressure cover 21 is engraved with a discharge hole 211 to form a back pressure, and the aperture size is asymmetrically distributed. The thread on the combined screw and the outer periphery of the back pressure plate are close to the wall of the barrel. Generally, the gap between the outer circumference of the thread and the back pressure plate and the inner wall of the dewatering barrel is 0.1 mm-0.2 mm. When the main motor 2 is driven, the transmission case 3 is driven by the combined screw to push the material forward. The reverse threaded element 22 and the back pressure cover 21 together generate a back pressure, and the surface of the back pressure cover 21 is engraved with a discharge hole having an asymmetrically distributed aperture shape, thereby ensuring the generation of back pressure and ensuring smooth material flow. Forward.

 Referring to the drawings, water outlet holes 24 are engraved on the circumference of the barrel at equal intervals, each group engraved with 2-3 discharge water holes, each of which forms a circumference, and each circumference is engraved with 5-20 water outlet holes. twenty four. Preferably, the outlet opening is located on the circumference of the junction between the forward conveying thread and the reverse thread. A filter device is disposed in the middle of the barrel wall where each set of water outlet holes 24 is located, and a filter screen 25 is disposed in the filter device. The filter net 25 is fixed to the net tray 26 and embedded in the net base 27, and the net base 27 is connected to the fixed interface 28, and the filter device is integrally fixed in the wall of the barrel at the water outlet hole 24.

 The vacuum suction device includes a vacuum chamber 12 disposed outside the water outlet and a pumping pipe 15 connected to the vacuum chamber. The vacuum chamber 12 is annular and closely attached to the periphery of the water outlet hole, and reference numeral 120 is a part constituting the vacuum chamber. A heater 14 is disposed between each of the two vacuum chambers 12 and is also coated on the outer wall of the barrel. The present invention can be provided with a reverse automatic flushing device that is turned on during the pulse period and flushes the filter screen 25 through a pumping conduit 15 connected to the vacuum chamber.

In the present invention, due to the use of the reverse threaded element 22, the back pressure plate 21, a relatively closed environment will be formed throughout the barrel. Under the condition that the heater 14 is working, when the sludge passes through the barrel, it enters a relatively closed environment in which temperature and pressure act together. According to the characteristics of the sludge, the state of mud-water separation will be achieved under the conditions of temperature and pressure matching. Since the array of water outlet holes 24 is engraved on the barrel, the vacuum system is activated and the moisture is extracted, which is extracted from point to surface and point and surface. Point-to-face extraction The form guarantees the efficiency of dehydration and ensures the dehydration. Moisture first passes through the ring vacuum chamber

12, then enter the vacuum tank 13.

 In the drawings, reference numeral 1 is a stand of the present invention, reference numeral 16 is a stand, reference numeral 17 is a cooling water pipe, and reference numeral 18 is a dicing cover.

 The sludge spiral vacuum dehydrator provided by the present invention is designed according to the physical and chemical characteristics of the sludge. Although the feed sludge contains up to 80% of water, the sludge itself is particulate and contains a large amount of chemicals such as microorganisms and flocculants, so the flowability of the sludge at normal temperature is very poor, and the present invention passes the forced feeding. Feed into the extrusion screw. In the environment where temperature and pressure are combined, the mud water is automatically separated. According to the principle of low energy consumption of sludge treatment, the moisture in the sludge is separated in liquid form. The specific advantages of this issue are divided into the following points:

 1. The large-lead adjustable rotary vane produces a forced downward pressure, and the sludge with extremely poor flow performance is forcibly fed into the extrusion screw. The gap between the rotating blade and the hopper wall is small, which avoids the occurrence of running materials. The variable frequency speed control realizes the control of the infinitely variable speed, ensuring the control of the feeding amount, thereby realizing the efficient operation of the production line.

 2. Adjustable combined screw design, the perfect combination of reverse threaded elements and threaded threaded elements creates a relatively closed environment within the barrel. In order to ensure that the sludge in the barrel can still be transported forward under the influence of the reverse force, a back pressure cover is provided, which ensures smooth delivery and relative pressure. The control of the amount of dewatering will be achieved depending on the different combinations of the thread elements. Avoid the line being completely fixed to a single dewatering rate value.

 3. After the heat transfer of the heater, the inside of the barrel will realize a relatively closed environment in which temperature and pressure work together, and the muddy water will be separated.

 4. The circumferentially arranged water outlet design of the dewatering barrel enables the vacuuming system to realize the point-to-face extraction form, so that the sludge in the barrel can be uniformly extracted.

 5. After the pulse backwashing device is set, clean the filter in a fixed time interval to ensure the smoothness of the filter, so that the dehydration can be carried out continuously.

Claims

Claim A sludge spiral vacuum dewatering machine, characterized in that it comprises a dewatering device and a sludge forced feeding device of a dewatering device; the dewatering device comprises a dewatering barrel and a combined screw disposed in the barrel; The combined screw includes a mandrel and a forward conveying threaded member and a reverse threaded member which are detachably arranged outside the mandrel, and the combined screw is further provided with a back pressure plate, and the back pressure plate is provided with a hole for the sludge to pass through; the barrel wall is provided with a water outlet hole, and the spiral vacuum dewatering machine is provided with a vacuum water absorption device at the corresponding dewatering hole; the spiral vacuum dewatering machine is further provided with a sewage in the dewatering device Mud heating device.  2. A sludge screw vacuum dewatering machine according to claim 1 wherein said back pressure plate is annular.  3. A sludge screw vacuum dewatering machine according to claim 1 or 2, wherein the threads on the combined screw and the outer periphery of the back pressure plate are adjacent to the barrel wall.  A sludge spiral vacuum dehydrator according to claim 1 or 2, wherein said water outlet hole is on a circumference of a boundary between a forward conveying thread and a reverse thread.  A sludge spiral vacuum dehydrator according to claim 1 or 2, wherein said heating means is a heater coated outside the barrel.  6. The sludge screw vacuum dewatering machine according to claim 1 or 2, wherein the vacuum suction device comprises a vacuum chamber disposed outside the water outlet hole and a pumping pipe connected to the vacuum chamber; A filtering device is provided at the hole.  . 7. A sludge spiral vacuum dewatering machine according to claim 1 or 2, wherein said sludge forced feeding device comprises a hopper, and the upper portion of said hopper is a cylindrical body at the lower part of the cone, the center of the hopper The feeding screw is arranged, and the screw in the cone body is further provided with a large blade for cutting, and the outer periphery of the thread of the feeding screw is close to the wall of the cylindrical hopper.  8. A sludge screw vacuum dewatering machine according to claim 7, wherein said blanking large blade angle is adjustably mounted to the feed screw.