FI65487C - ANORDNING FOER TILLVARATAGNING AV VAERME AV AVFALLSVATTEN - Google Patents

Description

1 65487 Sewage heat recovery unit Λ

Anordning för tillvaratagnlng av värme av avfallevatten v

The present invention relates to a device for recovering the heat of waste water, which device is as set out in claim 1.

5 For many years now, with rising energy prices and declining conventional energy reserves, efforts have been made to save energy in a variety of ways. Attention has then been mainly paid to various forms of natural heat recovery - such as geothermal energy, solar energy, etc. The area that has received relatively little attention has been heat recovery from wastewater. It is well known that in many contexts - public spas, dairies and even private households - thermal energy is wasted, for example in waste water disposal, without even attempting to recover and utilize this thermal energy within them, for example by heating clean cold domestic water.

To date, some devices for recovering the heat of wastewater 20 are already known. It is known e.g. a device in which a threaded pipe through which cold domestic water passes is placed in a hot sewage dump.

When this tubular spiral is discharged by the wastewater, a certain part of the heat is transferred to the cold water, whereby the proportion of the actual hot water required 25 decreases as the incoming cold water becomes even warmer.

Furthermore, a device is known in which waste water from several outlets is collected in one large tank with a partition or partitions with cold water coming in on one side 30. In this case, the heat is transferred through the walls to the cold water.

However, these known devices both have their own downsides. The most significant defect of the first-mentioned device 2 65487 is that the waste water entering the basin el valele 35 in no way evenly, so that the heating does not take place with a rllt-S 'power. It must also be regarded as a defect in such a device that, in use, such a coil is easily soiled on the upper sides and is not easy to clean at all, in which case hygiene is particularly impaired when the deposit is applied only to the pouring basin of a conventional sprayer.

The disadvantage of the second-mentioned device is that relatively large and complex arrangements and devices 43 are required for directing the waste water into the tank from several different consumption points. Likewise, all kinds of pump and other equipment are most often needed for such recovery devices to work properly. Furthermore, the heat transfer capacity of such devices is generally poor.

It is therefore an object of the present invention to provide a device which avoids the disadvantages of the above-mentioned known devices while substantially improving the recovery capacity and applicability. According to the invention, this is done by using a heat exchanger operating with a nested pipe system, a principle solution of which has previously been used mainly in connection with district heating transmission technology. The effluent heat recovery device is constructed so that the effluent is discharged along the inner pipe of the device, where no energy is lost to the outside air, 60 but all the energy discharged from the effluent during the passage

The outer tube, on the other hand, is preferably a material with a considerable heat dissipation capacity in order to further prevent the loss of thermal energy to the outside air. Plastic is particularly well suited as such a material. It is also desirable that the inner tube be a so-called duct pipe, because the heat transfer surface of such a pipe and thus also the ability is clearly better than that of a completely smooth pipe. In addition, it causes the cold water to vortex, which further improves the heat transfer properties.

75 Significant keksinnönmukaiselie device is that it is intended to apply in particular kalustekohtai- \ Sena, or it can be mounted to the standard is sprayed gurgle in such a way that its primary side is located between the shower basin outlet and the drain at the same time when an incoming 80 jet cold water passes through the secondary side.

An embodiment of the invention will be explained in more detail below with reference to the accompanying drawings, in which:

Fig. 1 shows the recovery device according to the invention from above and partly in a sectional view, 85 Fig. 2 shows the device according to Fig. 1 mounted in a jet dump basin in a sectional view along the line A-A in Fig. 1, and

Figure 3 shows a heat recovery apparatus of the arrow B in Figure 1 seen from above.

As shown in Fig. 1, a tube 2 is placed inside the tube 1, which may preferably be a comb tube to provide a higher heat transfer capacity. This assembly, in turn, is wound into a planar spiral that may be slightly higher in the center than at the edges to accelerate flow 95 in the wastewater pipe. Sewage is discharged into the pipe 3 and enters it into the pipe 2, from where it exits via the pipe k into the sewer network. To the pipe 1, which is preferably made of plastic, cold hot water is in turn fed through a connecting pipe 5. As it passes through the pipe 1, the cold domestic water is heated and discharged for use through the pipe 6 by the warm wastewater in the pipe 100 2.

An essential advantage of the above invention is that, as a cassette-like solution, it can even be retrofitted to, for example, a conventional sauna * 65487 105 in connection with a shower or the like in the same way as other plumbing fixtures. no wastewater is wasted, but everything passes through the heat exchanger, thus giving the cold 110 hot water in the pipe 1 as much of its energy as possible · This is further enhanced by the fact that the pipe 2 is a comb pipe, so that its heat transfer cap is substantially better than that of a smooth pipe.

As for the cleaning problems, it should be noted that the inner surface of the pipe 2 is smooth, so that the accumulation of dirt 115 is considerably low. · Furthermore, the device can be constructed so that the middle pipe threads are ·

Compared to the second known device mentioned above, the kek-120 device according to the invention has the advantage of a higher heat transfer capacity and the avoidance of the construction of expensive collection pipelines, which is particularly cumbersome in the case of old buildings. In addition, the heat resistance is also better, because the furniture-specific device el 125 has no unnecessary transfer pipes, as a result of which heat loss occurs by force ·

The invention is not limited only to the exemplary embodiment presented above, but can be more broadly modified within the scope of the following claims. 1