JPH0113566Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a mobile sludge dewatering device used for cleaning and managing sewage ditches, culverts, etc. Conventional technology In recent years, water and sewage systems have become widespread even in local cities.
Since each city manages the sewerage system, the total length of the sewerage system is expected to reach a considerable distance. Especially in the case of sewerage systems, if they are not regularly cleaned and maintained, sludge will naturally settle in the waterways and obstruct the drainage function, causing unfavorable environmental health conditions and causing complaints from local residents. I will receive it, so
A mobile sludge treatment device is installed in advance, and it is constantly operated.
Cleaning and maintenance of sewage ditches, culverts, etc. is being carried out. The device is equipped with a tank for collecting sludge mixed water, etc. on the loading platform of a truck, and a pumping hose is attached to this tank, and after moving the tank near the site by moving the vehicle, the hose is stretched out and the suction is carried out. The mouth of this tank is inserted into a place where sludge accumulates, such as a sewage ditch or culvert, and a vacuum pump powered by a car engine is turned to pump up the sewage into the tank and collect the accumulated sludge. be. and,
Sewage and sludge (hereinafter referred to as sludge, etc.) pumped up by the above-mentioned methods are transported and transported to a communal sewage treatment facility.
The items were collected and processed in bulk within the same facility. However, as sewage facilities are extended and completed, this type of sludge, etc. increases, and it is becoming difficult to expand or construct new joint treatment facilities to accommodate this increase. In other words, as urbanization around cities increases, it becomes necessary to purchase large areas of land, including measures to prevent pollution, and the amount of public investment increases.
It is becoming increasingly difficult to find suitable land, as local residents are becoming the target of protests by local residents who are concerned about the negative image of the environment and the risk of pollution caused by the facility's operation. Therefore, at present, the treatment of sludge and the like generated during the cleaning and maintenance of sewage ditches, culverts, etc. is no longer being treated all at once, but is being changed to being treated on-site as much as possible. Purpose This invention is designed to replace the conventional method of transporting sludge, etc. generated by cleaning and managing sewage ditches, culverts, etc., to a joint treatment facility where it is intensively treated. By installing a centrifugal dehydrator in parallel to the tank, a flocculant is immediately added to the sludge, etc. pumped into the tank, stirred and mixed, and after the time has elapsed for the result to be produced, it is sent to the centrifugal dehydrator to remove moisture. After separation, the solid sludge (hereinafter referred to as cake) is stored and packaged in bags made of water-permeable material such as linen, and handled.
In addition to making transportation easier, the separated water is returned to the sewers, culverts, etc. on the spot, solving the above difficulties, and the management of the sewers, culverts, etc. that meets the needs of the region and society. The purpose is to provide a mobile treatment device for sludge, etc. Moreover,
At that time, the diameter of the flocs created by the coagulant is appropriately increased to increase the solid content condensation effect, and to make it possible to perform necessary and sufficient dewatering without significantly increasing the rotational speed of the centrifugal dehydrator. Consideration has been given to reducing the transmission of vibrations generated by dehydration to the vehicle body and other equipment, thereby extending their service life as much as possible. Composition The gist of the present invention is as follows. A vehicle equipped with a transmission that enables switching of power transmission between a prime mover, a traveling mechanism side, and a hydraulic pump side, and support legs that can move upward and downward; a sealable sludge water tank mounted on each of the vehicles;
A hydraulic motor-driven sludge mixed water agitation means and flocculant addition means installed inside the tank, a separate hydraulic motor-driven vacuum pump for exhausting the air inside the tank in order to pump the sludge mixed water into the tank, and the tank. A pump mechanism driven by another hydraulic motor for pumping out the sludge mixed water etc. that has been stirred and mixed in the tank and transferring it to the dewatering means, installed in parallel with the tank equipment and driven at high speed by another hydraulic motor, A centrifugal dewatering basket that receives the transferred sludge water and the like and separates its moisture, and a dewatering basket that surrounds the basket and accommodates the entire dewatering basket, etc., and transports this to the vehicle.
A case with a separated water outlet and a sludge outlet, each supported by a spring, and a sludge scraper installed in the case and capable of being moved close to or away from the inner wall of the dewatering basket by means of a rack and pinion mechanism. A pressure oil distribution pipe system connecting the arm, the hydraulic pump and each hydraulic motor, and a control valve that enables opening, closing, and switching of the piping system, respectively, as necessary, are inserted into the delivery pipe system. This is a mobile sludge dewatering device characterized by the following: Next, an embodiment of the dewatering device of the present invention will be constructed according to the drawings. Embodiment FIG. 1 is a schematic side view of the mobile sludge dewatering device of the present invention, and in the figure, 1 is the moving means of the sludge dewatering device, that is, the vehicle part, and specifically, a chassis dedicated to fire engines is repurposed. Body work is easy. 1
1 is a cab-over engine, 12 is a driver's seat, and is equipped with control means for the vehicle's direction control device and engine power switching mechanism. 13 is a wheel, 14 is a loading platform, and the sludge pumping and processing device and all its operating mechanisms are mounted in the same parts. 15 is a transmission with a center PTO, and 16 is a pair of hydraulically driven lift legs installed directly at the front and rear of the lower part of the vehicle body, which prevents the vehicle body from resonating and moving due to vibrations generated by the device when operating this device. Therefore, when supporting the vehicle body on the ground by extending the legs, the supporting legs bypass the suspension mechanism of the vehicle body. 21 is a triple hydraulic pump driven by power transmitted from the PTO-equipped transmission. Reference numeral 32 denotes a vacuum pump, which is driven by the hydraulic motor 22 to discharge the air in the sludge storage/agitation tank 4 , lowering the pressure in that space, and removing the sludge that has settled and accumulated at key points in sewers and underdrains. , for sucking sand, etc. into the tank 4 together with sewage. 23 is installed above the same tank 4 , and stirs and mixes the polymer flocculant with the sludge, etc. in the additive tank.
Another hydraulic motor 42 for gently driving the stirring blades 33 so as to uniformly distribute the coagulant, coagulate and separate the solid content in sludge, etc., and precipitate it.
is a polymer flocculant storage container provided at the top of the tank 4 , in which the polymer coagulant is stirred and mixed using a stirrer similar to the stirring blades 33. As a result of the effect of adding a coagulant in the tank 4 , flocs containing solids have settled at the bottom of the tank. A screw pump 25 driven by a hydraulic motor 24 is
Another hydraulic motor installed in the upper center of the dehydrator 5 for rotating the dehydrating basket at high speed, 59
is used to remove the cake from the inner wall of the cage when the sludge, etc. sent in is dehydrated by the dewatering basket and becomes a cake, and this cake is deposited in excess of a predetermined amount or unevenly inside the basket. A handle for operating the cake scraping arm, 62 is a buffer support device that supports the dehydrator etc. on a trolley to isolate the vibrations generated during dehydration operation and prevents them from being transmitted to the car body, and 63 is a handle for removing the cake removed from the dehydration basket. This is a lid and chute for opening and closing the sludge cake discharge port for taking out the sludge cake out of the dehydrator case. The driving means 2 for each of the above-mentioned hydraulic motors is generally a second
It is composed of the illustrated hydraulic circuit. In Figure 2,
26 is an oil tank, its capacity is 100, 21
is a triple oil pump driven by the engine 11, 21 _-1 has a rated output of 210 Kgf/cm ² and a discharge rate of 85/min, 21 _-2 and 21 _-3 each have a rated output of 210 Kgf/cm ² , A pump with a discharge rate of 21/min is connected. and pump 21 _-1
is the theoretical displacement amount 49 via the dual control valve 27
The cc/rev hydraulic motor 22 or 25 is connected to the pump _21-2 via the control valve 28 to control the theoretical oil amount of 101.
The pump ^21-3 is connected via a control valve 29 to a hydraulic motor 23 with a hydraulic pressure of cm 3 /rpm to operate and stop a hydraulic motor 24 with a theoretical oil volume _of 101 cm ³ /rpm. Now, when the power transmission mechanism of the engine 11 is switched and the hydraulic pump 21 is driven, the state shown in the second diagram is obtained.
The oil discharged from the pump 21 _-1 from the oil tank 26 through the strainer 30 passes through the circuit 31 and passes through the check valve to the port T ₂ of the control valve 27.
B ₂ to activate the hydraulic motor 22 which drives the vacuum pump 32 and then returns to the tank 26 . A throttle valve is connected to the hydraulic circuit in parallel with the hydraulic motor 22, and is adjusted so that an amount of oil matching the load of the vacuum pump 32 is sent to the hydraulic motor 22. In this respect, the circuits of the hydraulic motors 23, 24 and 25 are also similar. vacuum pump 3
2, by discharging the air in the sludge storage tank, which has been made airtight in advance, to the outside, the pressure inside the tank is lowered, and the sewage is transferred into the tank through the suction pipe that connects the storage tank 4 and the required parts of the sewage ditch and underdrain. It also sucks up accumulated sludge, dirt, etc. Therefore, in general, the storage tank 4 cannot be airtight until it is filled with sludge and the like. At the same time, it is desirable to drip and add a polymer flocculant at a weight ratio of 1 to 2% from the flocculant container placed at the top of the storage tank 4 to the sludge, etc. in the tank. After the water is pumped up, the control valve 28 is operated to connect port P and port A, and port _B and port T.
3 and gently rotate the stirring blades to uniformly mix the flocculant and form flocs of an appropriate size, thereby uniformly condensing the solid content in sludge, etc.
They settle on the bottom of the tank and are separated from the water. The pressure oil that rotates the hydraulic motor 23 enters the circuit 38 from ports B and T, passes through an oil cooler 39 and a filter, and is returned to the oil tank 26. At that time, if the control valve 28 is operated in the opposite direction, port P and port B, port A and port T
Since these are in communication with each other, the motor 23 and therefore the stirring blades 33 reverse and stir, changing the flow of the sludge, etc. in the tank 4 , and it is possible to fully achieve the effect of homogeneous mixing. After the tank 4 is filled with sludge, etc., the control valve 27 is returned to its original position and the operation of the vacuum pump 32 is stopped, while the airtightness of the storage tank 4 is released to reduce the effect of adding the polymer flocculant. (This condition can be confirmed from the outside via a level gauge.) Thoroughly stir and mix the sludge, etc. in the tank, and then operate the control valve 29 to control port P, port A, and port B and port T are connected, pressure oil from the hydraulic motor _21-3 is guided to the hydraulic motor 24 through the circuit 36, and this is driven to turn the screw pump to remove the sludge, etc. that has settled at the bottom of the tank 4 . Transfer the containing flocs to the centrifugal dehydrator. Although not shown, the sludge, etc. in the tank can be removed by installing a switching valve or by installing piping so that the hydraulic motor 22 can be reversed, and by reversing the vacuum pump 32 and pressurizing air into the storage tank. By transferring the water to the dehydrator side, equipment such as the screw pump 34 can be made unnecessary. Before that, operate the control valve 27 to connect port T ₁ and port B ₂ , and
P ₁ and port A ₁ are shut off, and the hydraulic motor 21 _-1
The dewatering cage of the centrifugal dewatering machine must be rotated at high speed by introducing the pressure oil from the centrifugal dewatering machine to the hydraulic motor 25 through the circuit 31 and the check valve and driving the motor. Concentrated sludge and the like sent into the dewatering basket are separated into cake and water there, the cake is deposited on the inner wall of the basket, and the water is collected by the dehydrator case and returned to the old sewage ditch, culvert, etc. The dewatering basket itself has a large diameter and a large moment of inertia, and it rotates at high speed.As a cake of sludge and other substances accumulates on the inner wall, the moment of inertia becomes even larger, so the hydraulic circuit is closed by operating the control valve 27. However, since the rotation does not suddenly stop even when the cage rotates, an unreasonable force is applied to each member when the cage stops rotating. Therefore, when the valve 27 is restored to its original state, oil flows back to the pressure oil motor 25 through the throttle valve piped in parallel, causing the centrifugal cage to rotate due to the moment of inertia, and when this forcibly rotates the hydraulic motor 25, the motor 25 functions as a pump, it sucks up oil from the oil tank 26 through the throttle valve, and as a result, the hydraulic motor 25 acts as a brake, gradually braking the rotation of the dehydration basket, and also mechanically A brake mechanism is provided to manually brake the rotation of the cage. the above-mentioned control valve 27,
28 and 29 are installed together at the upper part of the rear end of the loading platform 14, and are provided in a position where the entire process can be seen and convenient for operation. FIG. 3 shows a perspective view of the storage/stirring tank equipment 4 arranged in parallel with the centrifugal dewatering device 5. In the figure, 23 is a hydraulic motor for rotating the stirring blade 33 installed on the upper part of the tank body 41; With another hydraulic motor driving the screw pump 34, the tank body 41 has approximately 1500
It consists of an FRP container with a capacity of 1,500 x 1,500 mm, and the lower part is shaped like a boat's bottom to prevent sludge from remaining in the corners, and the entire structure is airtight. Reference numeral 42 denotes a polymer flocculant container equipped with an openable/closable lid, in which the flocculant is stirred and mixed by a stirrer coaxial with the stirring blade 33 to supply a homogeneous liquid. 43 is a coarse mesh board,
A device that filters out coarse dust and lumps mixed in the sludge pumped into the tank and separates them to prevent them from flowing into the treatment equipment and damaging the equipment. It is necessary to periodically open the tank body and perform maintenance work to remove excess material. Reference numeral 44 denotes a central section, in which a stirring blade 33 attached to the end of the rotating shaft of the hydraulic motor 23 is installed, and rotates slowly (about 50 rpm).
Stir and mix sludge, etc. to which a flocculant has been added. Firstly, by evenly mixing the flocculant and uniformly distributing flocs of an appropriate diameter, the solid content in the sludge is fully flocculated and fixed. The second purpose is to separate the floc from water and allow it to settle and concentrate at the bottom of the tank. 46 is a pipe communicating with the air suction port of the vacuum pump 32; 47 is a pipe communicating with the storage tank, indicating the direction in which sludge, etc. flows in from the sludge collecting pipe; 48 is a screw pump 34;
This is a valve provided in a flow path for pumping up sludge, etc. inside the tank, and is used to seal the tank 4 when pumping up sludge, etc. into the storage tank 4 . For example, Evergrowth C-144 [trade name, manufactured by Ebara Inferco Co., Ltd.] at a weight ratio of 2% is added to the sludge, etc. pumped into the tank through a pipe, shutoff valve, etc., and then heated for about 10 to 20 minutes. By stirring and mixing,
Solids in sludge, etc. are uniformly coagulated and separated from water. Additionally, depending on the quality of the sludge, an oil coagulant or the like may be added. By processing in this way, it is possible to obtain the dehydration effect without increasing the rotation speed of the centrifugal dehydrator during the next step of dehydration treatment, and the amount of vibration of the dehydrator during operation can be reduced. , the structure of the buffer support device of the dehydrator 5 and the support legs 16 of the vehicle body can be simplified. 49
As mentioned above, is a drainage pipe that connects to the electric pump that directly discharges only the supernatant water that has already been separated in the tank 4 to the outside of the tank as necessary. pump 34
When the sludge has been completely transferred to the dehydrator 5 and only water remains in the tank, economical sludge treatment can be achieved by directly discharging the water. In addition, the storage tank is equipped with a level gauge,
The condition of the sewage can be seen from the outside. FIG. 4 is a sectional view of a centrifugal dehydrator attached to the stirring tank 4 , and in the figure, 25 is a centrifugal dehydrator basket 5.
This is a hydraulic motor for rotating 2 at high speed, and both are connected by a main shaft 51. Diameter 800φmm×
The bottom of the dewatering basket 52, which has a size of 500 mm, is formed into a drum shape by reducing its diameter, and the outer periphery is supported at three locations using springs so as to be resilient in the direction of the central axis by rollers 53. , basket 52
The bearing is designed to easily absorb vibrations even if the cake is unevenly adhered to the inner wall and rotates at high speed (800 to 1000 rpm). Reference numeral 54 denotes a case/container of a centrifugal dehydrator, which collects water separated from sludge etc. by the rotation of the water storage basket 51 and discharges it from a separated water drain pipe 61 provided at the bottom of the case. In addition to opening a sludge discharge port 55 in the center of the lower bottom for discharging cakes such as sludge adhering to the inner wall of the basket 51 to the outside of the dehydrator, the upper lid is equipped with a hydraulic motor 25, a sludge introduction pipe 60, and a cake scraper. A handle 59 for operating the take-up arm 56 is installed, and a spring support means for the dewatering cage shaft support roller 53 is provided at the lower part, and the whole is mounted floating on the loading platform 14 via a buffer support device 62, and Therefore, the vibration generated in the dehydrator during the dewatering operation is cut off, and the transmission of the vibration to the loading platform 14 is reduced or eliminated. The cake scraping arm 56 is connected to the dewatering case 54 by a rod 57.
The scraping arm 56 is slidably supported in the radial direction at the central portion of the dewatering basket 52 by rotating a pinion 58 provided on a rod 57 that easily meshes with the handle 59. Can be close to or far away from. 63
is a lid and cake transfer chute provided at the sludge discharge port 55, which is opened and closed by a manual mechanism. The method of operating the device with the structure explained above is as follows:
The outline is as follows. Transport the device to the required location and store it in the storage/stirring tank 4.
After adjusting the engine to a sealed state and switching the engine to the hydraulic pump 21 side via the PTO mechanism, the control handle 27 is operated to operate the hydraulic motor 22, that is, the vacuum pump 32, and remove the air in the tank 4 . Extend the pumping hose to pump up sewage, sludge, soil, etc. from the required locations such as sewage ditches and culverts into the tank. At this time, it is desirable to add the polymer flocculant dropwise to the sludge or the like at a weight ratio of 1 to 2% via a shutoff valve. At the same time, control valve 2
8 to drive the hydraulic motor 23 to gently stir the sludge in the tank (approximately 50 rpm), uniformly distribute the flocculant, coagulate all the solids in the floc, and stir the sludge in the tank in an appropriate manner. Care is taken that the floc formed in the diameter settles to the bottom of the tank. In this way, when the storage capacity of the tank equipment is exhausted, the control valve 27 is operated to stop the operation of the vacuum pump 32, the tank is unsealed, and the flocculant addition effect is achieved by stirring for about 10 to 20 minutes if necessary. When the amount of water has fully appeared, the control valve 27 is operated to rotate the hydraulic motor 25 at high speed to remove the water from the dewatering basket 5.
2, then operate the control valve 29 to drive the screw pump 34 via the hydraulic motor 24 to send out sludge, etc. in the tank from the bottom side into the dewatering basket 52.
At this time, large flocs of sludge condensed by adding a coagulant to the sludge in the tank grow, settle and concentrate at the bottom of the tank, and are sent to the dehydrator, so the rotation speed of the dewatering basket is reduced to 600 rpm. A noticeable dehydration effect occurs when the speed is increased to 1000rpm.
When the cake is rotated for about 5 minutes, depending on the quality of the sludge, etc., the remaining cake will be dehydrated to the point where it cannot hold its shape even if squeezed tightly, i.e., to the level of wet sand (approximately 65% water content). has been done. In short, the effect of the polymer flocculant is fully utilized and the dehydration rate is increased by rotating at a relatively low speed. The dehydrated and separated water is collected in a drain pipe 61 and directly returned to the old sewer, culvert, etc. At this time, it is preferable to pass it through a filter to remove the coagulant floc. If more than a predetermined amount (approximately 15 cm thick) of cake adheres to the inner wall of the dehydration basket 52, the dehydration efficiency will decrease and the vibration will become intense. When the cake layer is brought closer to the inner wall surface, the cake layer adhering to the wall surface and rotating together with the dehydration basket is intercepted by the scraping arm 56, and is scraped off one by one from the surface layer, and falls due to gravity to the cake discharge port. 55, the dehydration basket can be cleaned and the dehydration function can be restored again. The scraped cake passes through the drum-shaped discharge port at the bottom of the basket and is deposited on the cake discharge port 55 and the lid/chute 63, so a bag made of water-permeable material such as linen is prepared and placed at the end of the chute. When the lid 63 is opened manually, the accumulated cake can be slid down and guided and stored and packaged in the same bag, making subsequent handling and transportation very easy. The above-mentioned operation is repeated until the sludge and the like disappear from the storage/stirring tank 4 , but it goes without saying that the process can be arbitrarily changed as necessary. For example, sludge with flocculant added, etc.
During gentle stirring and mixing, the solid content is gradually separated into flocs containing coagulation and water, and only the flocs settle and concentrate at the bottom of the stirring tank 4 .
Since the supernatant water is separated at the top of the tank, by opening the suction port of the screw pump 34 at the bottom of the tank, only the concentrated content such as sludge is sent to the centrifugal dehydrator 5 side, and the other water is pumped to a separate electric pump. Since it becomes possible to return the sludge directly from the tank 4 to the sewage ditch by means of a pump, it also becomes possible to carry out economical treatment of sludge and the like. Further, the stirring tank 4 does not have to be filled to the point where it cannot proceed to the dehydration treatment of sludge or the like, and the control valve can be operated freely depending on the situation. However, the order of operations must follow the established rules described above. Thus, according to the device of this embodiment, sludge, etc. pumped up from places where sludge, earth and sand accumulate in sewers and underdrains can be economically processed on-site and formed into cakes that are small in volume and easy to handle. can,
It is possible to avoid the uneconomical cost of transporting water that is not directly related to the management of sewers, culverts, etc. to a joint treatment facility as in conventional means. Effects The treatment equipment of the present invention can be moved anywhere that a sludge removal vehicle can run (for this purpose, a 2-4 ton vehicle is used), and has excellent mobility. It stores the sludge generated by cleaning ditches, culverts, etc., and if necessary, not only dehydrates it on the spot to reduce its volume, but also makes it possible to package the resulting cake for easy handling and transportation. At the same time, the separated water can be returned directly to the old sewage ditch, culvert, etc., so there is no risk of environmental pollution or pollution caused by the treatment, and it is recommended to prepare a large number of such treatment equipment. For example, it is possible to avoid the difficulties of expanding or constructing a new large-scale centralized treatment facility, which was the case in the past.In addition, it eliminates the waste of transporting water that is not directly related to the cleaning process, and reduces overall sewage drainage. It has the advantage that cleaning and management of culverts, etc. can be carried out economically and easily. Furthermore, depending on its quality, the resulting cake can be reused as a variety of materials, such as potting material for plant cultivation, mixed material for blocks, and aggregate for road paving. Furthermore, for administrative parties, they are free from problems such as difficulty in acquiring land for expanding sludge treatment facilities in the future and persuading local residents, and are flexible to meet the needs of local residents. It also has the advantage of being able to respond to

[Brief explanation of drawings]

Figure 1 is a schematic side view of the mobile sludge dewatering equipment of the present invention, Figure 2 is its hydraulic system diagram, Figure 3 is a perspective view of the sludge storage and stirring tank equipment that constitutes the treatment equipment, and Figure 4 shows a schematic cross-sectional view of a centrifugal dewatering device for sludge, etc. 1...Vehicle body, 15...Transmission with PTO, 21...Triple hydraulic pump, 22, 23,
24 and 25...hydraulic motor, 27, 28 and 29...control valve, 32...vacuum pump, 3
3... Stirring blade, 34... Screw pump, 4 ... Storage/stirring tank, 42... Polymer flocculant container, 5 ...
... Centrifugal dehydrator, 52 ... Dehydration basket, 56 ... Cake scraping arm, 59 ... Handle, 62 ... Buffer support mechanism, 63 ... Cake discharge opening/closing lid and chute.

Claims (1)

[Scope of utility model registration request] A vehicle equipped with a transmission that enables switching of power transmission between a prime mover, a strike mechanism side, and a hydraulic pump side, and support legs that can move upward and downward; a sealable sludge water tank mounted on each of the vehicles;
A hydraulic motor-driven sludge mixed water agitation means and flocculant addition means installed inside the tank, a separate hydraulic motor-driven vacuum pump for exhausting the air inside the tank in order to pump the sludge mixed water into the tank, and the tank. A pump mechanism driven by another hydraulic motor for pumping out the sludge mixed water etc. that has been stirred and mixed in the tank and transferring it to the dewatering means is installed in parallel with the tank equipment, and is driven at high speed by another hydraulic motor. A centrifugal dewatering basket that receives transferred sludge water, etc. and separates its moisture, and a centrifugal dewatering basket that surrounds the basket to house the dewatering basket, etc., and supports this with respect to the vehicle via a spring, respectively. a case equipped with a water outlet and a sludge outlet; a sludge scraping arm installed in the case and capable of moving close to or away from the inner wall of the dewatering basket by means of a rack-and-pinion mechanism; and between the hydraulic pump and each hydraulic motor. 1. A mobile sludge dewatering device characterized in that a pressure oil delivery pipe system that connects the pipes and a control valve that allows the pipe systems to be opened, closed, and switched as necessary are inserted into the delivery pipe system.