JPH0260815B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to methods and apparatus for the excavation and disposal of dredged soil resulting from the construction and/or maintenance of channels, ditches, ditches, slips, and the like. In one form, it has application in all kinds of waterways, whatever their width and depth, and the excavated soil is injected into the air and falls like a spray, onto the land surface and/or or deposited on the surface of the water in relatively wide, thin sheets disposed at the same distance, usually transverse to the dredging site.

In another form of the invention, soil, such as a slurry, is transported through a floating dredger tube to a distant jetting soil transporter for aerially depositing soil at locations that are too far to reach by jetting from a dredger. Pumped to ship. In this arrangement, the reaction of the slurry injection, which at least assists in moving the dredger, can be replaced by a submersible jet or other form of propellant.

In recent years, the environmental effects of constructing and maintaining waterways, landfills, and drainage canals of all types have received significant public attention and been the subject of extensive government regulation. All current forms of dredging and chemical and mechanical removal of aquatic vegetation are rapidly becoming untenable. Furthermore, the cost of dredging has increased to such an extent that it curtails proper maintenance and management, effectively limiting service and increasing the likelihood of widespread flooding due to reduced drainage flow.

Dredging of channels, ditches, ditches, and the like has taken many forms. The discharged soil may be dumped along one or both sides of the dredging site, stacked in berms as far as the length of the boom allows, and transported by truck or earth barge to a remote point, or transported to a remote point. water is pumped to ponds, landfills, or similar locations, all of which are harmful to the environment. In most cases, the formation of unsightly and harmful land mounds and obstructions, the formation of shoals that impede boat navigation and natural water flow, and the destructive overburden of fragile marshes. It was neither practical nor possible to level out the slope of the discharged soil so that it would not occur.

Current dredging practices are particularly detrimental to the marine life cycle when carried out in tidal waters, saltwater marshes, and similar locations. Although regulations have been established that limit the allowable height increases adjacent to dredging operations, in many locations it is not possible to comply with such regulations;
Currently ignored.

Dredging heads are known which can supply slurry that can be pumped from the area of a dredged trench excavated by the head. The width of the head may be smaller than an earth carrier or other form of floating support structure, such as that shown in U.S. Pat. No. 3,412,862, or as disclosed in U.S. Pat. No. 3,962,803. They may have substantially the same width. Applicant's U.S. Pat. No. 3,971,148 and related U.S. Pat.
It is also mentioned in No. 3521387.

In addition to the growth of fruiting aquatic plants, which is increasingly stimulated by the nutrients contained in industrial and domestic wastewater, most waterways contain silt, muck,
A constant accumulation of unsolidified sediment occurs in the form of decaying plants, etc. Such sediment builds up on the natural or dredged bottom of the waterway, limiting and impeding navigation and drainage rates.

With the method and apparatus provided according to the present invention,
Solids in a dredged trench with a width substantially equal to or greater than the floating support structure may be sprayed directly or indirectly from the dredger into the air, resulting in a substantial adverse environmental impact. The soil in the dredged trench can be deposited with the minimum amount of soil.

That is, traditionally, soil dredged by suction dredgers was simply pumped onto nearby land, and because each discharge pipe installation required a large amount of soil to be pumped, A deposit is built up. These piles are then leveled with a bulldozer to spread the soil over an area. Such conventional soil leveling has a negative impact on the environment.
This is because such leveling of the soil cannot be spread over a very large area and the leveled soil will inevitably be very thick and cover the plants and vegetation adjacent to the channel being dredged. .

In contrast, the device of the invention does not cause environmental pollution. This is because the dredged soil is spread relatively uniformly and thinly over a large area, allowing the soil-covered foliage to grow through the soil. That is, in the practice of the present invention, the soil is injected into the air at considerable distances, and therefore, there is no significant separation of the soil by size, as in the case of suction dredging with a low pressure pump as described above. Because the soil is injected through the air toward the land adjacent to the channel being dredged, the deposit on the land is relatively uniform and relatively thin, typically less than 2 inches (50.8 mm) thick. be. Such a uniform and thin layer of soil does not adversely affect the plants or vegetation from which the soil is being drained, and therefore practice of the present invention is considered "environmentally acceptable."

Typically, soil is discharged onto land adjacent to the channel being dredged. However, it is also possible to discharge soil onto a body of water adjacent to the trench being dredged. Even when soil is injected onto a body of water, the soil is evenly distributed in a thin layer and sinks to the bottom. The soil is discharged a sufficient distance from the dredged trench so that it does not "flow back" into the dredged trench, so that the water bottom in the area where the soil is sprayed is only slightly elevated. . Such minimal deposition on the water bottom has only a slight environmental impact on marine plants, so even if soil is injected onto the water, there will be minimal negative environmental impact. Furthermore, when discharging soil onto the water, the dredged soil is simply moved above the water bed and therefore does not pose a problem of marine pollution.

Dredge trenches can be dug into tidal ponds, wetlands, unconsolidated sediments, and other submerged soils that can be made into a slurry.
In addition to being pumped, the slurry can be forced through a reducing nozzle at high velocity to inject the soil, so the slurry
It falls like a spray and can be spread out in a relatively wide, thin sheet far and/or to the side from the dredge trench immediately adjacent to the dredger.

In one embodiment of the new method for treating dredged material, the firing spray pattern of the nozzle structure is as follows. That is, at the operating pressure of the pumping means, the slurry is transferred in a widely distributed manner to the sides of the longitudinal axis of the dredging trench, typically in a width of 5 to 15 times the width of the dredging trench. The spray pattern is controlled by a nozzle diffuser.

Two high pressure nozzles are installed on the dredger to expel the soil. Due to the high pressure created in the nozzle, a significant reaction force is generated, and if the nozzle is oriented backwards with respect to the direction of movement of the dredger, this reaction force will propel the dredger. The magnitude of the reaction force that propels the dredger forward depends on the angle at which the nozzle is directed backwards, and the pressure released by the pump is also a factor that affects the reaction force. The steering force produced by the nozzle shall be transverse to the direction of movement of the dredger;
The degree of effectiveness of the steering force then depends on the lateral discharge angle. Since the discharge direction of the nozzle can be changed steplessly, the magnitude of the propulsive force and steering force generated by the nozzle can also be changed steplessly. It should be understood that the dredger does not rely solely on the aforementioned reaction forces for propulsion and maneuvering, as the dredger is equipped with a propeller, which also imparts forward motion to the dredger. In fact, it is common to propel dredgers using cables moored to the shore, and the present invention can make use of such propulsion systems if desired.

Preferably, the reaction force of the nozzle structure provided by the lateral and slightly rearward injection of the dredged material slurry is used as part of the force for propelling and steering the floating support structure. However,
The use of nozzle reaction to propel and steer a floating support structure is an incidental aspect of the invention, and an important concept of the invention is to move dredged soil far away from the dredging site. (e.g., 100 feet or more) through the air in a thin layer so that the sprayed soil does not have an adverse effect on the environment.

Under severe weather and environmental conditions, other supplementary means may be required to provide additional thrust and maneuvering, such as auxiliary jets, inboard and outboard engines driving propellers, tugs, etc.

Since the nozzle reaction is proportional to the flow rate of the slurry through the nozzle structure, forward movement of the floating support structure is reduced when the density of the slurry tends to reduce flow through the pump and nozzle structure. Therefore, the speed of forward movement tends to be matched to the dredging conditions, and dredging and slurry production overload by the cutter head is self-controlled to a large extent. As a result, downtime due to clogging of the pump and nozzle structure is reduced.

To reduce clogging of the pump intake, an auxiliary water jet may be provided at the intake. A guard bar may also be used to define a casing around cutter head augers that are provided with teeth to break up hard materials for slurry processing.

Objects and advantages of the invention will be understood from the following description and accompanying drawings.

The method described below is based on the oversight of those in the state and federal departments and professional bodies responsible for regulating activities deemed harmful to the environment in numerous locations, including Florida and other locations on the high seas. It resulted from several years of extensive experimental efforts carried out below. During this experimental period, many modifications were made to accommodate the widely varying conditions experienced within different locations as well as along the same waterway. During this period of development, full disclosure of progress was made in the licensing and regulation of dredging on the high seas and in various Florida newspapers and internal publications as early as 1979.
Publications regarding this progress, which appeared on May 15, informed those engaged in the process.

It was found that the density of the slurry in the excavated dredge trench was significantly influenced by the speed of dredge movement. Initial efforts to use nozzle reaction to move and steer a floating support were not satisfactory and many modifications were made before satisfactory results were obtained. Under certain conditions, it became necessary to use auxiliary steering and push navigation to advance the dredge cutter.

In the present invention, the ratio of solid to liquid in the slurry is limited to 5 to 10%, and the reason is as follows. That is, in the present invention, dredged and pumped slurry is sprayed into the air over a considerable distance. In order for the slurry to reach the desired distance, it must contain a significant amount of liquid. If the ratio of solids to liquid exceeds 10%, even if the slurry is injected into the air, it will not fly much, and furthermore, if a slurry with a high solids ratio is to be sucked, a significantly higher output will be required from the pump. That will happen.

Also, another method that maintains the solids ratio between 5 and 10% is
One significance is that environmental impact standards can be met when implementing the invention. The amount of solids deposited on the land or water surface receiving the air-injected slurry must be relatively small. To control the amount of solids deposited to be small, ie relatively uniform and thin, the proportion of solids in the air-injected slurry must be low. By maintaining the solids ratio at 5-10%, it is possible to control the amount of solids deposited to a small amount.

In dredging equipment, the above numerical limitation requirements are met by the operator controlling the amount of solids entering the dredging head at any one time. This control is not determined mathematically or automatically, but relies on the skill of the operator to accurately sense the operating conditions of the dredging head. The solids ratio of the slurry is dependent on the depth of the cutter head immersion into the solids at the bottom of the channel being dredged and the speed at which the dredge head is moved. The operator determines whether the appropriate solids ratio of slurry is being aspirated by monitoring the injected slurry flow and by monitoring the engine speed and operating noise of the dredging device. If the slurry is too light, the engine will run too fast and the monitoring operator will immediately notice that the solids ratio of the slurry is too low. Conversely, if the solids ratio of the slurry becomes excessively high, an excessive load is placed on the engine, which reduces the engine speed and reduces the slurry injection distance. In this case, the operator reduces the speed of movement of the dredging head or raises the dredging head several centimeters to reduce the solids content of the slurry.

To be practical, the means for excavating and transferring soil for dredging operations must be capable of handling large areas at low cost and rapidly. The method used must be relatively free of downtime due to clogging, etc., and the results must be relatively uniform and compliant with environmental regulations. In order to pump discharged soil through pipes to locations far from dredging operations, the pressure, density, degree of grinding, and other variables established in the past may have been unsatisfactory for aerial transfer of soil from a nozzle. discovered.

Example 1 During Applicant's recent experimental dredging in Louisiana, approximately 79,000 yards (72,237 m) of silt were removed in approximately 30 hours, and the soil was transported through the air next to the dredged trench, and the soil was transported through the air to the sides of the dredged trench. It spread out lightly like a thin rain ribbon about 100 feet (30.48 m) wide. In this test, the silt was relatively light and the slurry density was on the order of 5% solids. The pressure sent by the pump is
The air transfer was on the order of 40 pounds per square inch (2.8124 Kg/cm ² ) and was carried out through two 21/2 inch (63.5 mm) nozzles with adjustable air diffusers. The average travel speed of the dredge trench cutter was approximately 41 feet/minute (12.4968 m/minute) during the actual plowing period, excluding downtime. Extra thrust and maneuverability was provided by an attached pusher tug.

Example 2 When a dredged trench dug into a waterway is filled with aquatic vegetation and decaying vegetation, the density of the fibrous material and the The length cut must be carefully controlled. Using a grinding cutter bar in the pump, such as that disclosed in my U.S. Pat.
is 3 inches (76.2
mm) smaller.

The hull 20 of the dredger 10 may take any suitable form that provides shallow water, stability, and steering speed under the influence of the thrust propulsion of the adjustable jet nozzles 12 and 14. The auxiliary means of operation is
Submersible jets 16 and 18 located on both sides of the front of the hull 20 and a self-cleaning screw propeller 2
It can take the form of 2,24.

The hull 20 includes at its forward end bifurcated spaced apart hull sections 26 and 28 and a two-part pivoting boom 3 mounted on a pivot pin 32.
0 is accepted. The boom 30 supports at its forward end a dredge cutter head 34 having a depth control cylinder 34', which is described in my U.S. Pat. No. 3,971,148 issued July 27, 1976. You can follow the instructions in the section. The cutter head 34 creates a box-shaped cut, that is, a dredging trench 35 in front of the dredger 10, and the dredger 10 can follow the cutter head 34 at all water depths, as well as when digging into shallow water at a shallow depth. As such, the dredging groove is preferably at least slightly wider than the hull 20.

The typical width, length, and height above water of the hull 20 used in the present invention is 14 to 20 feet (4.2
~6m), 30~50 feet (9~15m) and 6~
It is 10 feet (1.8-3 m).

Hydraulically operated cutter head shield 36
is shown pivotally supported about a shaft 38 supported on cutter head 34 to provide material confinement. A flexible suction tube 40 having a flexible suction sensor 41 is preferably incorporated into a pump 42 with shear vanes as disclosed in the aforementioned U.S. patent application.
and the cutter head 34 to further crush solids in the slurry passing through the cutter head 34;
Reduce system clogging to acceptable operating levels. Sensor 41 assists in the operation of propellers 22 and 24.

The discharge tube 44 of the pump 42 has a Y-shaped section 46 to which is coupled a flexible conduit 48 that extends to the inlet ends of the adjustable jet nozzles 12 and 14. The nozzles 12 and 14 are
Preferably, it is located at the forward end of the hull 20 and adjacent the cutter head 34. In practice, this arrangement has been found to provide the best steering speed under jet reaction propulsion and to place the jet in the driver's forward view.

The support structure for the jet nozzles 12, 14 is
Bracket 50 located at the forward corner of the hull 20
a rigid vertical column 52 that includes a
is installed. A rotatable sleeve 52'
Rod 5 supported on vertical post 52 and pivotally connected to bracket 58 secured to sleeve 52'.
6 and is rotated about a vertical column 52 by a hydraulic cylinder 54 which is pivotally connected to the hull 20 at one end. Horizontal stays 52'' provide support for the vertical posts 52 to better support the reaction forces of the jet nozzles 12 and 14 and help transmit this reaction to the hull 20.

If nozzles 12 and 14 are oriented at 90 degrees to the right and left with respect to the direction of movement of the dredger, nozzle 1
2 and 14 have no forward propulsion effect on the dredged ditch. In order for the reaction force of the nozzles 12, 14 to tend to move the dredger forward, the nozzles must be directed "backward" (at least slightly). The more aft the nozzle is directed, the greater the propulsive effect produced by the nozzle, but the less distance the soil will be sprayed from the dredger. When the cutter head engages the soil, significant resistance is often encountered, in which case the propeller 22 must become the primary means of propelling the dredger forward, and also if the nozzles 16, 18 If you point it backwards, you can increase the propulsion force. In addition, the magnitude of the reaction force on the nozzle depends on the inner diameter of the nozzle, the density of the fluid, the fluid jetting speed (which is affected by pressure), etc., and a person skilled in the art with basic knowledge of fluid mechanics can explain this. Since it should be possible to easily obtain it depending on the actual situation, the details will be omitted here. Furthermore, the orientation of nozzles 16, 18 is determined solely by the operator and the results sought to be achieved. Moshi nozzle 1
2, 14 are oriented at right angles to the path of the dredger, all maneuvering can be done by the nozzles 16, 18. The orientation of the nozzles 12, 14, 16, 18 requires only common sense and experience on the part of the operator controlling the direction of movement of the dredger, and the propeller 22 when needed to provide additional forward thrust to the dredger.
No skill is required to operate the and 24.

Supporting the nozzles 12 and 14 for pivoting about a horizontal axis is a support member 60 secured to the vertical sleeve 52'. A swingable member 60' is supported within the support member 60, and an arm 62
is pivotally secured to the support member 60 to a rod of a hydraulic cylinder 64', and the lower end of the cylinder 64' is pivotally connected at 66 to an arm 66' that is secured to the sleeve 52'. . Part 6
Attached to the nozzles 12 and 14 is a bracket 60'' which is fixed to and oscillated with the sleeve 5 through an arc of the order of 160 degrees.
2' swing and member 6 through an arc of the order of 105 degrees.
2 is suitable for injecting the slurry and for moving and maneuvering the dredger 10;
Actually found, however, both nozzles 1
The member 60' can be adjusted so that 2 and 14 can discharge the slurry laterally on the same side of the dredger 10, or along the dredge trench being dug by the cutter head 34 in areas such as traffic, special locations, etc. Avoid spraying through nozzles 12 and 14.
It will be appreciated that it is also possible to adjust the

As shown in FIG. 5, nozzles 12 and 14 are directing dredge discharge to either side of the dredge 10 and to the dredge being dug by cutter head 34. As shown in FIG. Spray pattern 68 of nozzle 12 is shown as is pattern 70 of nozzle 14.

In FIG. 6, the spray pattern 72 of nozzle 12 is shown to be substantially different from the pattern 74 of nozzle 14. This difference results from adjustments to the air diffuser or other suitable means, as detailed below. Figure 7 shows pattern 7.
4 is shown in side view, with nozzle 12 removed for illustrative purposes. In the front view of FIG. 8, spray patterns 72 and 74 can take the shape shown when nozzles 12 and 14 are adjusted as shown in FIG.

FIG. 9 is a view similar to FIG. 6 showing nozzles 12 and 14, both directed toward the same side of dredger 10 and having similar spray patterns 76 and 78, respectively. This arrangement should be used when all discharged soil should be placed on the same side of a dredged trench, such as to avoid spray from passing traffic, docks or other structures. Can be done. Jets 16 and 18
It will be noticed that the nozzles 12 and 14 are oriented to correspond to the reaction of the nozzles 12 and 14 in the position shown in FIG.

10 to 12, when the location where soil is to be placed during dredging exceeds the range of the onboard nozzles of the dredger 10, the nozzles 12, 14 and the pump 42 are uncoupled, and the pump 42 and spray monitoring A connection is made with the earth carrier 80. This connection can be made in a known manner through the use of floating dredger tubes 82.

As shown in FIG.
or tethered to a dead-men 84. Nozzle 86
is supported on a suitable upright body on the earth carrier 80,
It is raised and lowered and swung through an arc in the same manner as described for nozzle 12 in the description of FIGS. 1-3. In this way, the discharged soil is placed on top of the bank 82.

To remotely control the operation of the spray monitoring earth carrier 80, suitable power and control lines from the dredger 10 are conveyed to the earth carrier 80 by a structure suspending tube 82. A self-contained remotely operated power unit 88 with a control line 90
is the hydraulic system pump 92 for the control unit 94.
to provide power. A suitable solenoid control valve, not shown, for raising and rotating the nozzle 86 is remotely operated through a control line 96 from the dredger 10.

The discharged soil to be placed on shore 82 is removed from the dredging trench of cutter head 34 and transferred to dredger 10.
From there, the soil is pumped through pipe 82 to the intake 98 of soil carrier 82 and then under the control of an operator on dredger 10, the soil is sprayed onto shore 82 in a relatively wide and thin distribution. In performing this step, dredger 10 continues to utilize the heading control jet system provided by jets 16, 18 and thrust-increasing propellers 22, 24 for propulsion and directional control.

In FIG. 3, the nozzle 12 is connected to the air diffuser 10.
0, the diffuser 100, in its simplest form, has a knob 104 at one end and an outer end for axial adjustment to intersect the jet stream of the nozzle 12 and direct the spray. Threaded rod 102 with point 106 adapted to change shape
includes.

In FIGS. 7 and 8, a dredged trench 35 is shown being excavated within the wetland 108, with placement in areas 110 and 112 on either side of the dredged trench 35. Because the spray patterns 72 and 74 are different, the width of the soil placement and the amount of buildup are also different.

Figures 13 and 14 show the application of this development to high-altitude dredging. Here, the dredger 10 is being used to dredge a trench that connects to an open body of water 114. As shown, the trench 11
6 is the width of the dredging groove 35, and the nozzles 12 and 14
is depositing the dredged material in a thin cover along both sides of the cut, with minimal impact on the environment along the cut 116 and open water 114.

As shown, a suitable rotary excavation attachment 11
8 is disposed above and in front of the cutter head 34 and is hydraulically rotated counterclockwise to engage and dig up the high ground. The attachment 118 has a horizontally extending central shaft 119 supporting a series of axially spaced spiders 120 .
It can take many forms, such as having a shovel or the like mounted on the outer end of a radial arm. The excavated upland material is directed into the path of cutter head 34, slurried as it is conveyed into the inlet of pump 42, and atomized by nozzles 12 and 14.

To fully understand the starting point of the method and apparatus for disposal of waste soil disclosed herein, all conventional methods in commercial use involve pumping waste soil to a containment site. This included creating an artificial berm and bank on the side of the excavation by using a pipe system to create an island, or by casting with a boom bucket on the adjacent side of the excavation. The only other alternative available was to haul the discharged soil by haulage vessels or ships to deep waters or distant immediate disposal areas. All of these processes create environmental hazards that are currently unacceptable. Also, such methods are immutable and costly.

In practice, the method and apparatus of the present invention involves slurrying the soil ahead of the movement of a floating dredger or other conveyance vehicle having a pump; pressurizing the prepared slurry for passage through the respective nozzles; passing the slurry through one or more nozzles to provide aerial spray distance capability using a controllable aeration device and horizontally and vertically controlled nozzles;
Involves discharging soil slurry thinly and widely as rain over a large area; such discharging to the side of the excavation is carried out with little or no permanent impact on the environment. .

Additionally, in addition to propelling and steering, or at least assisting with, the dredger 10 using the reaction of the aerial injection nozzles 12 and 14, the anchors
Disposal of soil by continuous movement without winches, pipes, etc. provides greater flexibility, speed, and cost savings previously unavailable to authorities that regulate the use of the high seas and wetlands. It is being experienced in demonstrations held at

FIG. 15 is a partially cross-sectional schematic diagram showing the water jet 121 directed toward the intake 40' of the suction tube 40. Appropriate trash guard 12
3 surrounds the cutter head 34 (not shown) and protects the cutter head 34 from large objects that might clog the cutter head and/or the intake 40'. water jet 1
21 tends to break up material moving towards the intake 40' and reduce clogging.

To assist in breaking up the material to be dredged, in FIG.
It has 125 teeth and is called a back hoe.
enable it to function in this way.

Horizontal water jets 16 and 18 in Figures 1 and 2
have a suitable mechanism 122 located at their upper end.
Preferably, it is mounted for rotation about a vertical axis through 360 degrees. In practice, mechanism 122 may take the form of a 360 degree position servomechanism that remotely controls the dredger's 10 magnetic compass. This provides automatic directional control for navigation and biases the disposal jet reaction forces of nozzles 12 and 14. Jets 16 and 18 are connected to the inlet 12
4 and a pump 126 with a Y-shaped discharge section 128
and a hydraulic pipe 130 extending to the jets 16, 18.
powered by a separate high-pressure water system with and. The operator controls for the dredger 10 are housed in a shelter 132, while operating power units for hydraulic and electric drives for pumps etc. are located at 134. The hydraulic drive for the propellers 22, 24 is indicated at 136.

A modification of the air diffuser 100 shown in FIG.
In FIG. 16, the air diffuser 13
8 is shown mounted on a spray nozzle 140 that corresponds to nozzles 12 and 14. Axial movement of control rod 142 across the jet stream to vary the spray pattern is controlled by a suitable stepper motor 144, which is controlled from shelter 132 by an operator.

FIG. 17 shows a schematic diagram of the attached control device of the dredger 10. In this figure, various labeled boxes are designated with the same reference numerals as structures shown in the figure to perform the functions described above.

[Brief explanation of the drawing]

Figure 1 is a side view of the floating support structure; Figure 2 is a side view of the floating support structure;
The figure is a plan view of figure 1, figure 3 is a front view of figure 1,
FIG. 4 is a rear end view of FIG. 1. FIG. 5 is a plan view of the waterway showing the relationship between the dredging ditch and the location where the airborne transport of the discharged soil takes place. FIG. 6 is a view similar to FIG. 5 with nozzles with different pattern adjustments. 7 is a side view of FIG. 5, and FIG. 8 is a front view of FIG. 5. 9th
The Figure is a similar view to Figure 5 showing the nozzles directed to the same side of the dredger. FIG. 10 is a far jet of slurry. FIG. 11 is an enlarged end view of the monitoring soil transport vessel of FIG. 10. Figure 12 shows the 10th
FIG. 2 is an enlarged side view of the monitoring soil transport vessel shown in FIG. FIG. 13 is a plan view of highland dredging, and FIG. 14 is a side view of FIG. 13. FIG. 15 is a schematic diagram of a cutter head with a slurry water jet to reduce clogging. FIG. 16 is an enlarged and corrected view of the spray diffuser. FIG. 17 is a schematic layout of the attached control device. 10... Dredger, 12, 14... Nozzle, 34
... cutter head, 42 ... pump, 44 ...
Exhaust pipe.

Claims (1)

[Scope of Claims] 1. A method for transferring soil to be dredged and discharged from channels, ditches, ditches and the like, while minimizing environmental impact on adjacent land and/or water bodies, comprising: A dredged trench is dug, a slurry containing about 5 to 10% solids is formed from the water in the dredged trench, and the slurry is directed to the water intake of a pump, and the slurry is pressurized and injected as it passes through the pump. to reduce the size of the solids so as to form an injectable slurry, to flow the injectable slurry from the pump to a reducing nozzle means to accelerate its flow, and to dispose of the soil in a wide, thin layer remote from the dredging channel. A method of transporting dredged soil that consists of spraying slurry in a spray pattern to a width approximately 5 to 10 times the width of the dredged trench. 2. A method according to claim 1, characterized in that the reaction of the nozzle means during the discharge of the slurry into the atmosphere is used to at least assist the movement of the dredger when digging the dredging trench. . 3. A method according to claim 2, characterized in that the nozzle means takes the form of at least two nozzles for simultaneously injecting soil on both sides of the dredged trench. 4. A method according to claim 2, characterized in that the reaction component imparting the steering force is adjustable both in direction and magnitude. 5. The reaction of each of the nozzles is independently adjustable.
The method described in section. 6. A method according to claim 2, characterized in that increasing the density of the slurry reduces the flow rate of the slurry and accordingly reduces the reaction force. 7 a floating support structure, a dredging head mounted at the forward end of said structure for forming a slurry with the material to be dredged and surrounding water, and a pump for comminuting and pressurizing said slurry; , the pair of injection nozzles coupled to the discharge side of the pump and mounted on the structure to transmit the reaction of the pair of injection nozzles to aid in operation of the structure. Equipment for transferring dredged soil. 8. The apparatus according to claim 7, wherein the head is a cutter head for digging a rectangular dredging trench. 9. Claim 7, wherein the nozzle is located adjacent to the front end.
The equipment described in section. 10. The apparatus of claim 7, wherein the nozzle is mounted for movement relative to the structure.