JP2003519768A - Batch type sludge dewatering equipment - Google Patents

Abstract

A dehydrating apparatus (10) includes a chamber (12) for receiving wet material to be dehydrated. A rotatably-mounted agitator (26) is provided with the chamber (12). The agitator (26) is adapted to agitate material in the chamber when the agitator rotates in a first direction (28) and convey the material out of the chamber when the agitator rotates in the other, second direction (30).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD OF THE INVENTION

The present invention relates to sludge dewatering, and more particularly to a sludge dewatering device operating in batch mode.

[0002]

[Background technology]

The treatment of sludge as waste has become a major issue as environmental standards have become increasingly stringent. One common solution for such waste treatment is the dehydrator described in Applicant's US Pat. No. 5,566,469. While this dehydrator achieves its intended purpose efficiently and economically, there is still room for improvement in terms of efficiency and cost as well as throughput of the device.

[0003]

[Outline of the Invention]

The sludge dewatering apparatus of the present invention incorporates a system that substantially improves sludge dewatering performance through indirect heating and batch modes.

[0004]

Detailed Description of the Preferred Embodiments

First, referring to FIGS. 1-4, in which the same reference numerals indicate the same and corresponding portions, the dehydrator 1
The 0 has a chamber 12 in the internal cavity 14 for receiving the material to be dehydrated. The chamber 12 has a cylindrical shape centered on a horizontal longitudinal center axis 16.

The chamber 12 has a heating annulus 18 for receiving heated thermal fluid from a thermal fluid heater 20 (see FIGS. 3 and 4). The heating annulus 18 is formed by an inner wall 22 and an outer wall 24 of the chamber. The outer wall 24 of the chamber is a heat insulating structure, and the inner wall 22 of the chamber heats the wet material of the inner cavity 14 by heat conduction through this inner wall.

[0006] The rotatably mounted stirring means 26 has an internal cavity 1 when rotating in the first direction.
4 to stir the material, and to deliver the material from the internal cavity 14 when rotating in the second, second direction. 1 and 2, the first direction is the direction of arrow 28 and the second and second direction is the direction of arrow 30.

The stirring means 26 receives the heated thermal fluid from the thermal fluid heater 20, and the stirring means 2
6 heats the wet material of the internal cavity 14 by heat conduction.

The stirring means 26 is attached so as to be rotatable about the central axis 16 of the chamber 12. The stirring means 26 comprises an annular shaft 32 along the central axis 16 which receives the heated fluid at its first end 34 and which receives a second,
The other end 36 is adapted to return hot fluid (see FIGS. 3 and 4).

The shaft 32 has a plurality of lateral discs 38 at substantially equidistant locations along the shaft 32.
Is fixed. The dimensions of these disks are about the same, and the outer diameter D1 of the disks is substantially smaller than the inner diameter D2 of the inner cavity 14. These disks 38,
A substantially annular gap 40 is formed between the inner wall 22 of the chamber.

As best shown in FIG. 3, the disk 38 comprises a hollow body having a cavity (42) therein. The first disk 44 closest to the shaft first end 34 is adapted to receive heated thermal fluid from the first end 34 thereof. Shaft second
The last disk closest to the end 36 of the shaft is adapted to return the heated thermal fluid to the second end 36 of the shaft. Each pair of adjacent discs 38 are connected at the circumferential surface 48 by a radially extending hollow connecting arm 52 and a hollow wiper tube 50 extending therebetween so that from one disc along this shaft. The heated fluid can flow from the first end 34 of the shaft to the second end 36 to the next disk. As best shown in FIG. 1, the wiper tube 50 is in close proximity to the inner wall 22 of the chamber so that the stirring means wipes and stirs the material as it rotates in the first direction. The angled conveyor bar 54 extends at an obtuse angle from each wiper tube 50 in the direction of the second rotation of the stirring means.

Each disk 38 includes radial walls 56, 5 defining an open wedge-shaped portion 60.
Have eight. The locations of these portions 60 are indexed along the shaft 32, as best shown in FIG. Because the connecting arm 52 is in alignment with the radial walls 56, 58, the conveyor bar 54 forces the dried material through these portions 60 as the stirring means rotates in the second direction.

As best shown in FIGS. 3 and 4, the present invention provides an indirectly heated dehydration system for vaporizing moisture from solids. The system comprises the following main components: dewatering chamber 12, dewatering chamber stirring means 26, thermal fluid heater 20, wet material storage / feed hopper 101, dried material discharge conveyor and bag rack 100 and wet granules. It consists of a scrubber / capacitor 102.

Dewatering Chamber 12 The static dewatering chamber 12 comprises a cylindrical chamber 14 with a thermofluid coil or, preferably, another cylindrical chamber surrounding the chamber forming an annular space 18 between the two. The heating fluid is such that it can pass through it. The dewatering chamber 12 has a thermal fluid inlet port 104, a thermal fluid discharge port 106, a material inlet port 108, a material discharge port 110, a discharged vapor discharge port 112, and a door 114 for accessing the internal structure of the apparatus. The entire combustion chamber is surrounded by an insulating blanket 116.

Stirring Means 26 The rotary stirring means 26 inside the dewatering chamber consists of a series of hollow disks 38 welded to a common shaft 32. These hollow discs 38 have four
A 0 ° wedge-shaped cutout 60 is provided to ensure that the level of wet material to be dewatered is equal throughout the length of the chamber and that the dried material can pass between the discs and drain. Become. The stirring means 26 is supported by a shaft 32 that penetrates bearings attached to both ends of the dehydration chamber. A thermal fluid rotary joint 118 is provided at each end of the shaft 32 to allow fluid to flow into the rotating shaft. All disks 38 are connected by wiper tubes 80 that pass the thermal fluid from one disk 38 to the next. This fluid is
A steel blank flange 120 (see FIG. 3) is press fit into the shaft 32 at the end of the shaft 32 which is welded inside the shaft past the first disc 44. The flange 122 is similarly welded at the other end to the inside of the last disc 46. The shaft 32 is perforated inside the first disc 44. Thus, the fluid flows into the first disc 44 and then from one disc 38 to the next through the wiper tube 50 and the connecting arm 52 and at the opposite end via the shaft 32 through the stirring means. It can flow out of 26. Wiper tube 50
Has a flat surface on one side and an angled conveyor bar 54 on the other side.
The flat surface moves into the material when the system is in the dewatering mode and the angled conveyor bar 54 moves into the material when in the discharge mode.

Wet Material Storage / Feed Hopper 100 The material storage / feed hopper 100 has a rotary wiper mechanism 124 that keeps the material feed rate to the screw auger 126 at the bottom constant. The screw auger 126 feeds the material from the hopper 100 to the dewatering chamber 12 via a feed pipe 128 fixed to the sludge inlet port 108.

Thermal Fluid Heater 20 The gas or electric thermal fluid heater 20 heats the fluid pumped through the annulus 18 of the dehydration chamber and the disc 38 of the stirring means. This thermal fluid system is a closed loop. The fluid discharged from the dehydrator is pushed back to the heater, reheated, and then sent back to the dehydrator.

Dried Material Discharge Bag Rack and Conveyor 101 The dried solids are discharged from the dewatering chamber 12 to a conveyor 130, which transfers the material to a receptacle 132. These receptacles include bags, dumpsters, silos, roll-off poppers, and the like.

Wet scrubber / condenser 102 Steam from the dehydrator 12 exits the dehydrator via duct 134,
A large number of water spray nozzles 136 are provided inside the duct. This water spray cools the gas stream and exhaust port 1 of the dehydrator before entering the Benryuri-type scrubber / cyclone 138 where a highly efficient scrubbing / cooling effect occurs.
Useful for collecting particulates from 12.

Operating Principle The material to be dried is placed in the material storage / feed hopper. The self-sliding gate is located in the dewatering chamber at the material inlet port opening that opens when the unit is filled and closes when the unit is in the dewatering or draining mode.
The hopper fills the dewatering chamber to the appropriate level for a given time interval. Once the dewatering chamber is filled, the dewatering process begins with the correct direction rotation of the agitating means, pumping the heated fluid to the dewatering chamber and agitating means. At the beginning of the drying cycle, the hot fluid is maintained at an elevated temperature when the moisture content of the material is highest. As the material dries near the end of the cycle, lower the oil temperature to avoid reaching the flash point. This prevents scoring or burning of the material. In the dewatering mode, the flat side of the wiper tube acts on the material.
During this period, the material is constantly agitated, lifted and baked so that it is exposed as much as possible to the heated surface area of the tubes, disks and cylinder walls of the agitation means. When the material is determined to be dry based on the timing cycle or by the temperature sensor, the system automatically opens the material discharge port door and reverses the direction of rotation of the agitation means to allow the angled conveyor bar to move. Allow it to act on the material. The angled conveyor bar moves the material toward the discharge port after each revolution to deposit the dried material on the conveyor. The dried material is sent from the conveyor to a receptacle or bag. When the dewatering device is empty, the system automatically closes the outlet port door and refills with the moist material and begins the next dewatering cycle. Due to the hermetic nature of this system, the exhaust gas from the dehydrator is virtually pure steam. Air scrubbers / condensers are designed to remove particulate matter entrained in the exhaust stream and condense as much vapor as possible back into liquid.

Although the present invention has been described with reference to particular embodiments, it will be appreciated by those skilled in the art that various modifications and design changes can be made. Such modifications and variations are intended to be included in the invention as long as they come within the scope of the appended claims.

[Brief description of drawings]

[Figure 1]   FIG. 1 is a partially cutaway end view of a dehydrator constructed according to the present invention.

[Fig. 2]   FIG. 2 is a perspective view of the stirring means used in the present invention.

[Figure 3]   FIG. 3 is a schematic diagram showing the flow of heated oil in this dehydrator.

[Figure 4]   FIG. 4 is a schematic diagram showing the system of the present invention in operation.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C02F 11/12 ZAB C02F 11/12 ZABB F26B 23/10 F26B 23/10 Z (72) Inventor Vigham, David , L United States Texas 79538 Nobis Box 166 F Term (Reference) 3L113 AA06 AB05 AC05 AC37 AC58 AC67 AC75 AC87 BA37 DA01 4D059 AA00 BD12 BD15 BD21 BJ03 BJ14 BJ17 CA14 CB04 CB06 4G037 AA11 CA03 CA05 EA03 403008 A03 AB20 BA03 DB20 BA03 A20 AB03 BA20 A03 AB20 BA03 EA10

Claims (5)

[Claims] 1. A chamber for receiving a wet material to be dehydrated, and a stirring means provided with the chamber and rotatably mounted therein, wherein the stirring means, when rotating in a first direction, is inside the chamber. The material is fed from its chamber when the material is agitated and is rotated in the second, second direction, and the agitation means receives the heated thermal fluid from the thermal fluid heater and agitates it. By heating the means, the wet material in the chamber is heated by heat conduction, and the stirring means is mounted so as to be rotatable around the center axis of the chamber. A tubular shaft extending therealong, the tubular shaft being adapted to receive heated thermal fluid at a first end and return the heated fluid at a second, other end. , Multiple laterally extending devices Discs are fixed to the shaft approximately equidistantly, these discs consist of a hollow body with a hollow interior, the first disc closest to the first end of the shaft being the first end of the shaft. A dewatering device adapted to receive heated hot fluid from the and the last disk closest to the second end of the shaft returns the heated hot fluid to the second end of the shaft. 2. Adjacent pairs of disks are connected at their circumferential surfaces by hollow wiper tubes extending between radially extending hollow connecting arms.
A heated thermal fluid can flow between the disks from the first end to the second end along the shaft, and the wiper tube is close to the inner wall of the chamber so that the stirring means is in the first direction. The device of claim 1 wherein the material is wiped and agitated when rotated. 3. The apparatus of claim 2 including an angled conveyor bar extending from each wiper tube at an obtuse angle toward the second direction of rotation of the stirring means. 4. Each disk has a radial wall defining an open wedge-shaped portion, the wedge-shaped portion being indexed along the shaft, and the connecting arms being in alignment with the radial wall. 4. The apparatus of claim 3, wherein the conveyor bar pushes the dried material through these portions when the stirring means rotates in the second direction. 5. A chamber having a cylindrical shape centered on a horizontal longitudinal center axis and receiving a wet material to be dehydrated in an inner cavity, and rotating in a first direction stirs the material in the inner cavity, 2, comprising a rotatably mounted stirring means adapted to deliver material from an internal cavity when rotated in the other direction, the chamber having a heating annulus formed by an inner wall and an outer wall, The heating annulus is adapted to receive heated thermal fluid from a thermal fluid heater, the outer wall is insulated, and heat transfer is conducted through the inner wall of the chamber to heat the wet material in the inner cavity, The stirring means is adapted to receive the heated thermal fluid from the thermal fluid heater, heat the stirring means, and heat the wet material in the internal cavity by heat conduction. During ~ Mounted for rotation as a stirrer, the stirring means comprises a tubular shaft extending along a central axis, the tubular shaft receiving a heated fluid heated at a first end and a second shaft At its other end for returning thermal fluid, a plurality of laterally extending discs fixed to its shaft at approximately equal intervals, the discs having approximately equal dimensions, Since the diameter is substantially smaller than the inner diameter of the inner cavity, a substantially annular gap is formed between the disc and the inner wall of the chamber, the disc comprising a hollow body having a hollow interior, the first body of the shaft. The first disc closest to the end receives heated thermal fluid from the first end of the shaft and the last disc closest to the second end of the shaft is heated to the second end of the shaft. To return the heated fluid Each adjacent pair of discs is circumferentially connected by a hollow wiper tube extending between radially extending hollow connecting arms so that there is a first gap along the shaft between the discs. The heated hot fluid can flow from the end to the second end, and the wiper tube is close to the inner wall of the chamber, so that when the stirring means rotates in the first direction, the material is wiped and stirred, An angled conveyor bar extending from each wiper tube towards the second direction of rotation of the stirring means at an obtuse angle, each disk having a radial wall defining an open wedge-shaped portion, the wedge-shaped portion being a shaft; And the connecting arms are aligned with the radial walls so that when the stirring means rotates in the second direction the conveyor bar pushes the dried material through these parts.