WO1981001525A1

WO1981001525A1 - Method of solid-liquid separation and apparatus therefor

Info

Publication number: WO1981001525A1
Application number: PCT/JP1979/000309
Authority: WO
Inventors: K Suzuki
Original assignee: K Suzuki
Priority date: 1979-12-05
Filing date: 1979-12-05
Publication date: 1981-06-11

Abstract

Technique for solid-liquid separation to be employed for a dehydration previous treatment in soil water processing or the like, and a method of solid-liquid separation which comprises cooling a suspension in a slowly stirred state without freezing, and the apparatus for practicing the method.

Description

Specification

Solid-liquid separation method and solid-liquid separation device

Technical field

The present invention relates to the solid-liquid component of the pretreatment of the dehydration treatment in the sewage treatment technology and the like.

This is related to the separation technology.

Dagger

冃 Kyoto Tech

The solid-liquid separation technology most similar to the present invention is roughly classified into a physicochemical treatment method and a heat treatment method. Solid-liquid separation technology is a method of sedimenting and separating solid particles, which are solid suspensions in wastewater.

The mode of sedimentation of the 10 particles varies depending on their concentration and properties.In general, when considering an ideal state where the concentration of suspended particles is low and the agglomeration property between particles is high, Free settling occurs. By the way, if the sedimentation speed differs according to each particle in the state where the particles are freely sedimenting, collision occurs between the particles, and if there is agglomeration property between the particles, is particles coalesce and large particles group I, so-called cohesive sedimentation. Furthermore, when the interaction becomes remarkable, collectively ¾] 9, interfacial sedimentation in the form of so-called flocculent flocks. Under such conditions, the interaction based on the agglomeration property between the particles lowers the free sedimentation speed of each unit particle.9, When the flocculent block is formed,

20 water is contained in it, and the sedimentation speed of the unit particle is remarkably reduced. In solid-liquid separation technology in sewage treatment technology, the higher the sedimentation speed, the higher the efficiency can be improved. Enhancing the sedimentation speed is an important issue in liquid separation technology.

To solve this problem, the physicochemical treatment method is inorganic.

25 Additive: A polymeric coagulant is added. This method is In order to weaken the charge repulsion of suspended particles in water, a charged substance is added to create entrainment that makes it easier to shift the dispersed state of each particle to the aggregated state, and to facilitate sedimentation. It is. However, the continuation of its mass use has been seriously affected on rivers, lakes, seas, etc., but it gradually accumulates, shrinks, and is hardly degradable, etc.], fish and shellfish, and even the human body. Pollution issues that may arise could be pointed out.

There is a heat treatment method as another method for solving the above-mentioned problems relating to the sedimentation velocity, which is roughly classified into a heat treatment method and a freeze-thaw method. At the very least, these methods are commonly used as sludge treatment technologies. The heat treatment method reduces the charge of sludge particles by applying heat to the sludge, and promotes agglomeration of the particles by removing water adhering to the surface. This method has an excellent feature in terms of improving the dehydration property in that the gel composition is exfoliated by thermal action and can be discharged to the capillary bound water and the internal water. generation of malodorous gases can not be avoid, also machine _c freeze-thaw method is disadvantageous inconvenience such as adhered residues causing harmful effects to solidify onto the frozen sludge, by connexion heat treatment method to melt It improves the cohesiveness of the particles in the same way as described above, but requires two-stage processing such as freeze-thawing, which leaves a problem in terms of processing efficiency.

Disclosure of the invention

In the solid-liquid separation method of the present invention, the suspension is stirred at a high speed, and the suspension is cooled to the extent that it does not freeze in that state. Under this condition, the suspension is cooled down to the point before freezing, so that water molecules adhering around the suspended particles are broken down. ,. (S)

The hydrophilicity of the turbid particles is lost. Thus, it is possible to reduce the zeta potential caused by all the water molecules attached to the surrounding water as the particles move through the water, thereby avoiding agglomeration and agglomerating the particles. Can be enhanced. On the other hand, the force for agglomerating fine δ fine particles existing in the liquid depends on the Brownian motion of the particles, turbulence fluctuation, and the attractive force of the Don Van der der Waals. The slow stirring effect of the suspension creates this condition, and the freezing point of the liquid in its natural state can be set low by the flow of the liquid by stirring.) It is convenient for reducing the zeta potential. Further, the stirring has an effect of avoiding the state of interfacial sedimentation or interference sedimentation. However, rapid agitation, on the contrary, lowers the coagulation sedimentation efficiency, so it is necessary to use slow agitation according to the conditions. By using this method, the efficiency of solid-liquid separation technology can be improved.However, since the method involves only 5 physical methods without adding a chemical substance, it can be used as a physicochemical method. There is no room for potential pollution problems that can be seen, there is no harm due to the generation of odorous gas such as the heat treatment method, and the method according to the present invention is similar in principle to the freeze-thaw method and has the same effect. Although it gives a gorgeous effect, it does not require heat treatment in the opposite relationship of freezing and thawing, and is only concerned with cooling, so it is excellent in terms of processing efficiency. Further, although the present invention relates to the pre-treatment of the dehydration treatment in the water treatment technology, the suspension has a property that the suspended particles have as a collecting property of the suspended particles. As a result, the obstacles in the over-dehydration process are eliminated, and a revolutionary effect that enables smooth work is also provided.

5 The solid-liquid separation device of the present invention is as shown in FIGS. 1 and 2], 9,1 G′Ή′Υ.:; Each is a device directly used for carrying out the solid-liquid separation method. The first embodiment is a solid-liquid separation device shown in FIG. In this apparatus, these tanks from the pre-cooling tank 1, the concentration tank 2, and the storage tank 3 are stacked and held in the same order. The precooling tank 1 has a suspension inlet 4 through it! ), The stirrer の of the slow stirring machine 5 is suspended so as to rotate slowly inside thereof], and the cooling pipe 7 is provided around! ), And a gate valve 8 is provided at the bottom. The concentrating tank 2 is suspended so that the stirring section 10 of the slow stirring machine 9 rotates at a low speed in the inside thereof, and a gate valve 11 is provided at the bottom of the tank and a net 12 is provided in the inner periphery. Because the tank 13 was held inside and fitted inside it], the gap 15 between the outside wall 14 was used as a liquid discharge passage. A discharge pipe 16 is provided at the lowermost part of the liquid outlet path. Note that, in the concentration tank 2 in this embodiment, a cooling pipe 17 is provided around the tank. Care is taken to suppress the temperature rise. The storage tank 3 has a sludge tilling pipe 18 at the bottom. The transfer pipe 18 is connected to a transfer pump or the like and further connected to the next processing step. In the storage tank of this embodiment, a water discharge pipe 19 is also provided at the bottom. Although the configuration of each tank has been described above, it is desirable that the outer walls of the pre-cooling tank 1 and the concentrating tank 2 be formed as a new thermal structure in order to prevent the influence of outside air.

Next, the operation of this device will be described.

First, the suspension flows into the precooling tank 1 through the inlet 4, in which the suspension is stirred by the stirring section の of the slow stirrer 5. ] 9, Cool as long as the liquid does not freeze in that state Because of the cooling by pipe 7, a state is created in which suspended particles tend to aggregate and settle while avoiding coagulation. That is, the role of the pre-cooling tank 1 is to create a state in which the solid-liquid separation of the suspension is performed efficiently. After the suspension is in that state, the gate valve 8 is opened and the suspension is allowed to flow down into the filtration tank 13 of the concentration tank 2. Thereafter, the gate valve 8 is closed, and the pre-cooling tank 1 receives the suspension to be processed next and starts the operation. On the other hand, the suspension flowing down into the filtration tank 13 is stirred by the stirring section 10 of the slow stirrer 9], and the suspended particles start to flocculate and settle. In the pre-cooling tank 1, suspended particles are easily settled and sedimented, so they settle out very quickly. Accumulate. The stirring action here prevents the freezing of the liquid, prevents the sedimentation at the interface or the interference sedimentation state, and also provides an effect of avoiding the clogging of the net 12. It is natural that the permeation tank 13 passes through the suspension, but the liquid flowing out of the side wall of the permeation tank 13 through the F network 12 contains no suspended particles and becomes a clear liquid. The liquid is transferred to the liquid processing step through the discharge pipe 16 from the gap 15 that is the discharge path. After the suspension in the permeation tank 13 is completed, a sludge consisting of suspended particles and moisture is deposited at the bottom of the permeation tank 13, At this stage, the gate valve 11 is opened and the sludge flows down into the storage tank 3. Thereafter, the gate valve 11 is closed, and the cooling tank 13 in the compression tank 2 receives the suspension cooled in the pre-cooling tank 1 and restarts the same overwork. Repeat this work

When returned, a considerable amount of sludge accumulates in the storage tank 5, which is transferred to the next processing step, the dehydration step, through the transfer pipe 18.

Ο:.: ΡΙ ' ^γ ' ⁰ Sent. In addition, when suspended water or the like is stored at the bottom of the storage tank 3, means for returning to the suspension through the water discharge pipe 19 is provided. By this work, this device smoothly implements the solid-liquid separation method described above, but also measures the inflow of the suspension into a 5-floor suite attached to the pre-cooling tank 1. J.Confirmation of the amount of accumulation in the concentration tank 2 and the storage tank 3 is performed electrically, and is automatically performed by transmitting to gate valves 8 and 11 and other transfer pumps. It can be controlled.

The second embodiment is a solid-liquid separation device shown in FIG. This device

10 is a pre-cooling tank 20, a storage tank 21, and a concentration tank ²² ]}, these tanks are juxtaposed, and a pipe 23 passes between the pre-cooling tank 20 and the storage tank 21; between the storage tank 21 and concentrated tank 22 is obtained by違通a tube 25. through the耘送port Nbu 2 ^4. Precooling tank 20 such as cooling gas and the outside ² 7 while flowing through the suspension of the helical tube 26

The suspension is cooled by ventilating the IS refrigerant. The storage tank 21 has a stirring section 29 of a slow stirring machine 28 suspended inside, and a cooling pipe 30 is provided around the storage tank 21. The concentrating tank 22 suspends the stirring part 32 of the slow stirrer 31 inside, penetrates a solenoid valve or a tubing bomb 33 with a pipe ³⁴ that is different from the bottom of the stirring part 32, and has a mesh 35 inside. I

20 The tank 36 is fitted and held by a bridge 37 and the like, and the gap 38 formed by the fitting is used as a liquid discharge path. In this example, a discharge pipe 39 is provided at the bottom of the liquid discharge path and at a required position. Although the configuration of each tank has been described above, it is desirable that the outside of each tank has a cross-sectional structure to prevent the influence of outside air.

C ' Next, the operation of this device will be described.

First, the suspension flows into the pre-cooling tank 20 through the inlet ^40, and is frozen in the flowing state by the cooling gas or the like that is flowing through the outside 2 while flowing through the spiral tube 26. Cooled. The cooled suspension 5 flows into the storage tank 21 through the pipe 23, and is slowly stirred in the storage tank 21, and is circulated around the tank 21 within a range where cooling is not possible in that state. Since it is cooled by the cooling pipe 30, a state in which coagulation and sedimentation is easily generated while avoiding coagulation is created as in the above-mentioned embodiment]). Thereafter, the suspension in the same state is transferred by the transfer pump 24.

10 is transferred to the concentration tank 22 through the pipe 25. In the concentration tank 22, the suspension starts to flocculate and settle, and at the same time, is suspended by the mesh 35 provided around the permeation tank 36. Smooth泸過tank for suspension already rapidly settle extremely because it is issued wound to facilitate the state of aggregation and settling in storage tank ² within 1, and glue properties dismantled in this case

Deposits on the bottom of IS 36. It is natural that the excess tank 36 passes through the suspension, but the liquid flowing out of the excess tank 36 through the net 35 does not contain suspended particles and becomes a clear liquid. From 38, it is transferred to the liquid processing step through the discharge pipe 39. After the suspension in the permeation tank 36 is completed, the suspended particles and

At this stage, the sludge from the water will accumulate. At this stage, the sludge is transferred to the next treatment stage, i.e., the water process, through a pipe 34 provided to the solenoid valve or the transfer pump 33. By this operation, this apparatus also smoothly implements the above-described method for solid-liquid separation. However, while the above-described apparatus stacks each tank, each tank can be arranged side by side.

²⁵ , which is convenient for installation in places where the height is restricted, and

O'.fFI

,. Ϊ ο " It is the same as the above-mentioned device that the electric automatic control is also possible.

1 and 2 are cross-sectional views of a main part of each embodiment of the solid-liquid separation device according to the present invention.

5 1… Pre-cooling tank, 2… Concentration tank, 3… Storage tank ヽ 4… Inlet, 5… Slow stirrer, ό… Stirrer, 7… Cooling pipe, 8… Gate valve, 9 … Slow stirrer, 10… Stirring unit, 1 s Gate valve, 12… 浐 mesh, 13… ^ Over tank, 14… Outer wall, 15… Gap, 16… Discharge pipe, 17… Cooling pipe, 18… Transfer pipe , 19 ... water discharge pipe, 20 ... pre-cooling tank, 2 "storage tank

10 tanks, 22 tanks, 23 tanks, 24 pipe pumps, 25 pipes, 26 spiral pipes, 27 external pipes, 28 slow mixers, 29 stirrers, 30 cooling Pipe, 31: slow stirrer, 32: stirrer, 33 pump, 34 ... pipe, 35 ... net, 36 ... ^ tank, 37 ... piece, 38 ... gap, 39-discharge pipe, 40 ... indicates the inlet.

15 BEST MODE FOR CARRYING OUT THE INVENTION

The present invention can be most efficiently implemented by the apparatus as shown in the above embodiment.

Industrial applicability

The present invention is very useful for improving the efficiency of sewage treatment technology. In addition, since the type of the treatment liquid is not limited as long as it is a suspension, it can be used in other fields such as the food processing industry and mining if the conditions are suitable.

Claims

The scope of the claims

1. A solid-liquid separation method characterized by cooling the suspension in a range where the suspension is not frozen while the suspension is stirred slowly.

2. A pre-cooling tank with a suspension inlet through which the stirring section of the slow stirrer is suspended, a cooling pipe around and a gate valve at the bottom The stirring part of the high-speed stirrer is suspended inside, a gate valve is attached at the bottom of the stirring part, and the excess tank with the inner circumference of the net is fitted and held. And a storage tank with a sludge feed pipe at the bottom.] 9, Pre-cooling 10 tanks, solid-liquid with stacking of the concentration tank and storage tank in the same order

3. Suspension pre-cooling tank and suspension section of slow stirring machine are suspended inside, and storage tank surrounding cooling pipe and stirring section of slow stirring machine are suspended inside. Connect to solenoid valve or transfer pump at the bottom

I A pipe with ⁵ pipes penetrated and a so-called internal tank with an internal tank fitted and held inside, and a condensing tank with a gap formed by the fitting inside as a liquid discharge path is juxtaposed and pre-cooled A solid-liquid separation device in which the tank and storage tank are connected by a pipe, and the storage tank and concentration tank are connected by a pipe via a transfer pump.

20