JPS5929080A - Flocculation treatment of dredged sludge water - Google Patents

Abstract

PURPOSE:To improve separability by settling and to improve the yield of reclamation, by adding a flocculating agent to dredged sludge in the plural positions of a sludge feed pipe and flocculating efficiently the sludge even if the residence time or flocculating conditions in the feed pipe change. CONSTITUTION:The sludge water produced by pumping and dredging, for example, harbor sludge contg. >=95% silt or clay and having a poor settling characteristic is fed through a sludge feed pipe 1 to a reclaimed land 2. A flocculating agent (e.g.; partially hydrolyzed substance of polyacrylamide) is fed from a flocculating agent tank 7 by a pump 8 and is partially fed to the sludge from the 1st feed point 12 and the 2nd feed point 13. The ratio of the flocculating agent to be added in this case is 60-80% at the point 12 and 40-20% at the point 13 and when an additional feed inlet is provided. The standard flow rate in the pipe at the feed points for the flocculating agent is usually 3-5m/sec and it is preferred to provided one feed point for each point in the pipe where the residence time of the flocculated sludge is sufficient to hold the sludge in a stabilized state, i.e. 1min 30sec - 2min after it has been flocculated by the injection of a flocculating agent. In the figure, 5 denotes a retarding basin, 9 a chemical feed pipe and 10 a partial feed pipe, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a coagulation treatment h' method for suspended mud water.

We use pumps to dredge the sediment that accumulates in rivers, lakes, and ports.
When transporting the muddy water generated to a landfill using a mud pipe, 11
A method is used in which a flocculant is cooled in the pipe path, and suspended solids, mainly fine particles such as silt and clay, in the muddy water are flocculated during transport, and then settled and separated at the destination landfill. ing. This method utilizes the flowing state of young mud water to perform the single-party stirring necessary for dissolving and flocculating the flocculant, and generally the mud pipe reaches the seawall from the rear dredge vessel Fuku. A coagulant is added at the point where the money is collected, and money is collected from this point in the mud pipe that leads to the landfill.

However, as the reclamation process progresses, the length of the slurry feed pipe becomes longer and the residence time after the flocculant is heated becomes longer, or if the flow condition inside the pipe changes due to branching, etc., the flow condition inside the pipe changes. The flocs that have grown are destroyed, and the sedimentation and separation of the flocculated mud becomes incomplete.

In general, in order to form coagulated flocs suitable for sedimentation separation14, it is necessary to continue moderate stirring for a certain period of time, and the flocs formed in this way maintain a stable state suitable for sedimentation separation under agitation. Although there is a limit to this, if the stirring time in the pile becomes longer or the stirring conditions become more intense, the flocs will be destroyed, making it unsuitable for sedimentation separation.

The floc formation time and steady-state duration are also affected by other agglomeration conditions, such as changes in soil quality due to soiling at the dredging location, changes in the degree of suspension due to changes in the mixing rate, etc. During the same stagnation, the flocs will be destroyed and the sedimentation separation effect will deteriorate.

When the flocs are destroyed and the sedimentation separation deteriorates, the polluted matter flows out, which reduces the yield of the landfill and deteriorates the water quality of the outflow fountain, causing environmental pollution. Between Nato: There is point C1.

This invention was made to improve the problems in the North American method as described above, and by adding a flocculant at the number of plates in the slurry pipe, the retention time or coagulation time in the slurry pipe can be improved. Even if the drainage condition changes, it can coagulate at a high rate, improve sedimentation separation, improve landfill yield, improve the quality of leftover water, and prevent environmental pollution. The purpose of the present invention is to provide a method for coagulating muddy water that can be treated.

This invention is a method in which muddy water is transported through a mud pipe, a flocculant is added to δ≧ to cause flocculation during the transport, and the flocculated mud is sedimented and separated at the destination, at multiple positions during the redundant transport. ′
(e) A method for collecting and treating dredged mud, which is characterized by adding 5 organic polymers (11) to the dredged mud.

One functional Okinapolymer mochi aggregation agent for the present invention is as follows:
Polyacrylamide, partial hydrolysates of polyacrylamide, polyacrylates, and the organic polymer flocculants of Sono, Ike, and Bechi are unsuccessful.

In the North American treatment method, these flocculants are injected into the slurry pipe at one point, and flocs are formed within 10 to 20 seconds after the flocculant is added, and a stable kasumi-gathering state is reached approximately 60 seconds later. This state lasts for 1 minute and 30 seconds to 2 minutes, but if the stirring state continues after that, the flocs will break down, and after about 1/2.5 minutes of the stable C gathering state, I is about 1
The sedimentation rate will be 15.

For this reason, the inside of the slurry pipe after removing the coagulant? :j'j'f
It is desirable to set the i1 time to 60 seconds or 2 minutes, but as the landfill iM position, that is, the position of the outlet from the slurry pipe, changes depending on the progress of the reclamation, the flocculant should be applied at 71:I at one point.
・When entering the water, the residence time cannot be within the above range. In addition, the tail pipe is complicatedly branched, and θ sludge is collected from many points and the landfill regresses at the same time, so it is extremely difficult to move the point where the collector enters.

This is x゛1, and I don't like it for sending mud and snow.
A stable floc state can be maintained for a long time by providing a settling point of 1 and applying partial pressure of the flocculant at two or more vertical points. This is thought to be due to the fact that even if the flocs produced by the first coagulating force press-in trowel are destroyed, they can be repaired by the appropriate coagulant. For the second time, after adding the conduit cutting metal box of 〆・f, it is not necessarily necessary to save detailed time.

The position where the crazy point of the ff1Ir collection agent is set is based on the normal top flow velocity of ~5 m/see, and the bending time is set at 1 minute 60 seconds to 2 minutes, which is the upper limit of the duration of stable flocs, every time it is noticed. It is preferable to provide one press-fit point in the area.

Of course, multiple units may be provided within the above range;
After the second injection, the solution may be allowed to stay beyond the above range and then injected again in front of the outlet. In this way, the number of press-fit points may be two or more. If the slurry pipe has branches, each branch can have two or more injection points.

The total amount of flocculant is 5 to 16 m9/A (relative to sludge), which is less than the amount added in the case of normal one-point injection, and this can be partially pressured. The injection ratio at each point is 60-80% of the total injection at the first injection point, and 40-20% from the second injection point onwards.
It is desirable to do so.

The injection point, removal amount, partial pressure ratio, etc. of the flocculant differ depending on the characteristics of each dredged sludge, dredging and landfill conditions, etc., so the flocculation conditions can be determined in advance by jar tests or field tests. .

Next, the present invention will be explained in more detail with reference to Examples.

The drawing shows a system diagram of the embodiment, where 1 is a mud feeding nail and 2 is a landfill site. The mud feeding pipe 1 has an outlet 6 at the end thereof opening at one end of the burial ground 2. The reclaimed land 2 is structured as a pond, connected to a retarding pond 5 by a partition bank 4, and a 1d spillway 6 is connected to the retarding pond 5.
is provided. 7 is a flocculant tank, through which the medicine pressure tank 9 is connected to the feeder pipe 1, and from the medicine pressure tank 9, the PE tank 10 flows through the slurry pipe through f4: it 11. 1
connected downstream. The contact point 1a of the medicinal pump 9 for the amount of mud fed 1 is the 1a point 12, and the connection point of the partial pressure pipe 10 is the second injection point 16.

In the example, the muddy water used was 95% clay.
9, the 1' mud surface velocity during natural sedimentation of mud is 0.0.
Pump dredging of port 115 mud with poor sinkability at 65m/hr.
This muddy water is sent to the landfill through the JMU device 1, and the flocculant (7F lyacrylamide partial hydrolyzate) is sent from the flocculant tank 7 by the pump 8, and then sent to the first injection point 1.
2 and 2a: Partial pressure was applied from entry point 16. The amount of mud fed by the pipe 1 is 1200 mJ/hr, the amount of medical pressure at the first sweat point 12 is 10 mm/β, and the % of the 21st point 16 is f: 3:
The child was 3 rng 7 ib, the time between the face part 1ki from the first press-in point 12 to the second press-in point 16 was 120 seconds, and the face time from iii'42 /i human point 16 to the outlet 6 was 10 seconds. Table 1 shows the properties of flocculated sludge near the outlet 6, and changes over time in the sludge settling capacity for the above two-point injection method and the case where the entire amount is injected only from the first or second injection point. -2.

Table 2 Regarding the state of sludge accumulation near the outlet 6, in the case of two-point injection, the agglomeration and granulation of sludge particles were good, and the formation of coarse flocs was clearly observed by visual observation. The sludge around 6 was piled up in layers. On the other hand, in the case of injection only at the first injection point, the sludge spread quickly into states at the outlet B, and the flocs were also relatively small.

In addition, in the case of injection only at the 2nd ω two-person point, the distance to the outlet 6 is short, so the flocculating effect is not fully exerted, and the partially flocculated sludge sinks, but the uncoagulated sludge becomes cloudy. It spread as.

Next, in the case of the turbidity at the entrance of the middle partition 4 in the above 5 tests (1), the turbidity at 2 points was 7 to 9 degrees for 10 days, the SS was 14 to 18 m9/A, and the public water discharged. It was below the standard, but if only the first and first insertion points were press-fitted, it would be cloudy.
16 ji, S S 32 m 97 A, 5 g 2 If only Ejin point is press-fitted, turbidity filter 2 trade, S S 65 lIl! 7
/A.

From the above results, it can be seen that in the case of 1.2-point injection, the flocculation and granulation properties of sludge particles are higher than in the case of single-point injection, and that the sedimentation compaction property is large and the clarification effect of separated water is also high.

Although the above embodiment is an example in which the present invention is applied to muddy water obtained by dredging port sludge with a pump, it can be similarly applied to other muddy water dredged from rivers, lakes, etc. When dredging these freshwater systems, PAC, Regret iv! It is also possible to use inorganic flocculants such as i.i., bread soil, ferric chloride, etc., and these can be added prior to the addition of the four-compound polymer flocculant.

In addition, as a polymer flocculant, it can be used in addition to the polyacrylamide type mentioned above. It is also possible to use a combination of raw materials and raw materials. In these cases, one of the flocculants can be removed at the first point, and the other flocculant can be press-fitted at the second point or later to produce a combined effect.

In addition, injection point withdrawal and other plasma collection matters! 7itf will not change the name.''I will stop.

As mentioned above, according to the present invention, since the structure is such that the slurry is added at the algebraic position of the slurry pipe, a stable collecting agent can be maintained for a long period of time, and the waste can be easily disposed of in a landfill. It has four effects, such as improving walking ability and improving the K quality of the octopus water.

41z and the previous year's explanation IA and is a system diagram of one embodiment of this invention, 1 is before mud feeding, 2 is a landfill, 5 is a retarding pond, 7 is a follow-up 111
Cao, 9 is medicine / + ministry, 10 is minutes, q three pipes.

Agent Patent Attorney Yanagi Hara Written Procedure Amendment (Method) Director-General of the Special Lodging Agency Kazuo Wakasugi Tono. Method 3 Relationship with the person making the amendment Patent applicant 4/Agent 105 YIL story 436
-4700 (1" 1 "1 [Earthwork; F Miyako Minato-ku Nishi Y'i
To L3'l'1l15 No. 8 (5, Number of inventions increased by amendment 07, ifj Positive object Detailed explanation of invention in specification Column Table-1 Table-2 419

Claims (2)

[Claims] (1) In the method of transporting dredged mud water through a mud pipe, adding a flocculant during the transport to perform flocculation, and separating the collected mud water at the destination, there are multiple points of transportation. A method for purchasing and discharging dredged muddy water, which involves adding one and three organic polymer flocculants to the dredged muddy water. (2) Cancer 5 addition ratio of flocculant (-1: 60 to 1 at the first injection point)
80 section, 40 to 20 section at the second press-in point・l"J 3
How to collect and dispose of the dredged muddy water described in item 1 of ``I Plant 1''. (filter) d; yt of dredged muddy water according to claim 1 or 2, wherein the collecting agent is polyacrylamide, polyacrylamide partial hydrolyzate, or polyacrylate;
Collection method.