ES2535875B1 - SYSTEM FOR THE RECOVERY OF HEAT FROM WASTEWATER - Google Patents

Abstract

System for the recovery of wastewater from sanitary sewage, which includes passing the set of sewage, before being sent to the general drain, through a wastewater passage selector (7), whose inlet section (9) it is surrounded by a peripheral chamber (11) that is in communication with said lowering section and has an auxiliary outlet (12) located at a lower height than the outlet (10) of the siphon, in which an actuated valve (13) is mounted ) responsible for directing the water to a thermal recovery facility or to the general drain.

Description

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SYSTEM FOR THE RECOVERY OF HEAT FROM WASTEWATER

DESCRIPTION

Field of the Invention

The present invention relates to a system for the recovery of heat from wastewater, especially sanitary water, which is sent to the general evacuation or drainage network, after use, at temperatures higher than those of feed or inlet Said water in a clean state.

The system of the invention is conceived as a means to take advantage of the thermal energy of the water that is poured through the sanitary water evacuation networks of buildings of different application, such as individual homes, housing blocks, hospitals, hotels, etc.

The waters that are discharged through the evacuation networks of a building can be classified as:

a) Gray waters, which are those that come from the set of sanitary devices, except toilets, and that are waters with a relative dirt, with little solid waste and with certain elements in solution, such as detergents, fats, etc.

b) Black waters, which are those that carry fecal matter from toilets. They are waters with high pollutant contents.

c) White waters, which are those from rain, snow, etc., collected on roofs and terraces of buildings. Generally this water has a low level of dirt.

The system of the invention is designed to be applied to the set of gray and black waters, without prior separation thereof, being indicated for installation in building downspouts or in the final collection of the collector that receives the different downspouts.

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Background of the invention

Systems of installations for the recovery of wastewater are already known, from the treatment of gray water originated in a building, for which the water from devices that can be fed with hot water is collected in a different conduit from the one used to drive the exit of toilets.

Black water from toilets is traditionally conducted to the drain or general drainage network. On the other hand, the gray waters, coming from devices that can optionally use hot water in their operation or function, are collected through a conduit that, generally, feeds a tank or storage tank, from where, depending on the temperature of the Stored water is sent to a thermal recovery facility or to the general drain. Wastewater heat recovery systems or installations that respond to this form of operation are described, for example, in patents ES2259921, US4550771, EP0532910 and GB2304877.

In all cases, an installation with different downspouts is required, one for the sewage and one for the gray waters, of the second of which the recovery or thermal use by different systems will be carried out.

The need to have two different downspouts in the building, means that the systems and installations described above can only be applied, in a cost-effective way, in new buildings, without practical possibility of application in already constructed buildings.

In other cases, the use of a heat exchanger is used at the exit of those sanitary devices whose operation generally uses hot water, such as showers and the like. In this regard, the patent ES2354548 and DE19817031 can be cited. These systems require the provision of a heat exchanger for each sanitary appliance, with independent recovery facilities, with the corresponding increase in cost.

Description of the invention

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The present invention aims to solve the problems set forth above, by means of a system that allows its application both in new works and in works already executed, without having to increase the number or arrangement of downspouts of the building and using a single system or installation of heat recovery, being necessary only to incorporate in the sewage collection network of the building of certain elements, whose assembly does not require modifying the general structure of the evacuation network.

According to the system of the invention, the set of gray and black waters of a building, which are collected through downspouts, are passed, before being sent to the general drain, through a wastewater passage selector which is composed of a siphon, whose entrance section is surrounded by a peripheral chamber with which it is in communication through holes or slots made in the wall of said section. This chamber has an auxiliary outlet that is located at a lower height than the siphon outlet and has an actuated valve mounted that controls the passage through this auxiliary outlet, depending on the temperature of the water that fills the peripheral chamber. When this temperature is higher than a preset value, the actuated valve deflects the water towards a heat recovery system, while when said temperature is lower than the preset value, it deflects the passage of water towards the general drainage of the building.

The auxiliary outlet of the peripheral chamber is located, as indicated, at a lower height than the exit of the siphon and is smaller in section than said siphon.

The actuated valve is activated by a thermal sensor that is mounted in the peripheral chamber.

The inlet section of the siphon will be arranged in prolongation with the conduction of general wastewater discharge in which the step selector of the invention is mounted.

The holes or grooves that the siphon inlet section is that is surrounded by the peripheral chamber, together with a filler filler material of this chamber, such as silica or others, constitute a filtering system that is intended to prevent the passage of solids from said inlet section of the siphon to the auxiliary output of the peripheral chamber.

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Preferably the siphon will be of practically constant section from its entrance to its exit, with said exit directed perpendicular to the entrance section. For its part, the auxiliary output will be located in the lower part of the peripheral chamber, for example in a direction parallel to the siphon inlet section.

With the constitution described and whatever the position of the actuated valve disposed at the auxiliary outlet, when a high mass composed of solid and liquid materials (called a plug) descends through the downspouts, for example from the discharge of a toilet , due to its mass and the rate of descent, it will tend to continue its circulation through the siphon, without passing through the filtering system, until reaching the exit of the siphon.

If part of this water passes through the filter system, due to its low temperature it would also be sent to the general drain by the valve actuated mounted on the auxiliary outlet.

As long as the thermal sensor does not determine that the fluid must pass to the thermal recovery facility, both the siphon outlet and the auxiliary outlet of the peripheral chamber evacuate the fluid to the general drain.

On the contrary, whenever the temperature sensor detects that the temperature of the water passing to the peripheral chamber is higher than the preset value, the actuated valve will direct this water towards the heat recovery system.

With the system described, it is ensured that only thermal water that reaches a temperature above the preset value arrives at the thermal recovery installation. On the other hand, solid waste from the discharge of a toilet is prevented from reaching said installation due to the existence of the auxiliary outlet of the filter system that forms the peripheral chamber.

Brief description of the drawings

An attached, non-limiting, example of the thermal recovery system of the invention is shown in the accompanying drawings.

In the drawings:

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Figure 1 is a diagram of a wastewater evacuation installation, which includes the thermal recovery system of the invention.

Figure 2 shows a side elevation of the wastewater passage selector installed in the downspouts of the water drainage network of a building, according to the invention.

Figure 3 shows in perspective the peripheral chamber that becomes part of the wastewater passage selector.

Figure 4 is a diametral section of the peripheral chamber mounted on the siphon inlet section of the wastewater passage selector.

Detailed description of one embodiment

The characteristics of the system of the invention, as well as the simplicity of application thereof, can be better understood with the following description, made with reference to the exemplary embodiment shown in the attached drawings.

Figure 1 shows the scheme of a network of sanitary water evacuation, belonging to a house or work already executed, which includes various systems or installations of thermal recovery, these can be an accumulator with internal coil, an exchanger of plates, a tubular exchanger or any other thermal recovery system that operates for the same purpose.

Different devices (1) that can use hot water in their operation, such as washing machine, dishwasher, sink, etc., as well as a series of sanitary devices

(2) through which hot water can also be used, as well as a toilet

(3), whose operation or cleaning is always carried out by means of the cold water supply are illustrated in Figure 1.

The drain of the appliances (1) can be collected in a drain (4) and that of the appliances (2) and toilet (3) in a common drain (5). The downspouts (4 and 5) lead to a common downspout (6) that pours into the sewer or general drainage network.

In the example represented in figure 1, in each of the downspouts (4 and 5) a wastewater passage selector is provided or formed which is generally indicated by reference number (7) and which is constituted, as best can be seen in

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Figure 2, by a siphon (8) comprising an input section (9) and an output section (10), the input section (9) being aligned with the downpipe (4 or 5) in which it is installed . Around the entrance section (9) of the siphon (8) an annular chamber (11) is formed which is located below the exit section (10) of the siphon (8) and which has an auxiliary outlet ( 12), which is also located below the outlet section (10) of the siphon (8), and has an actuated valve (13) mounted that is activated by a thermal probe (14) installed inside the tank (11).

As can be seen in Figure 4, the wall of the inlet section (9) of the passage selector around which the peripheral chamber (11) is formed has slots or holes (15), and the filler filler material of the chamber (39) through which the water that passes through the section (9) of the passage selector to the peripheral chamber (11) will pass.

From the actuated valve (13) the auxiliary outlet (12) of the peripheral chamber (11) forks into two mouths (16 and 17) the first of which leads, through the pipe (18) to a thermal recovery installation (19), while the mouth (17) leads, through a pipe (20) to the common downpipe (6) that leads to the general drain.

When the thermal probe (14) detects that the water contained in the peripheral chamber (11) is at a temperature higher than a predetermined value, it will direct the water outlet through the mouth (16). On the contrary, when the temperature of this water is below the preset value, it will be directed through the mouth (17) to be sent to the general drain.

As shown in Figure 3, the peripheral chamber (11) will have openings (21 and 22) in its bases for coupling to the inlet section (9) of the passage selector. In addition, the peripheral chamber (11) can be provided at its bases with an upper mouth (23) and a lower one (24), with corresponding caps, for emptying and replacing the filtering material filled by said chamber. Also in the upper base you can have a water outlet (25) with solenoid valve, for cleaning the interior, a socket (26) for the vent valve and an overflow (27), while in the lower base you will have the auxiliary outlet (12) and a hole (28) for mounting the thermal probe (14), figure 1.

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As can be seen in Figure 2, the siphon (8) can be provided, in the intermediate section located at a lower height, with a manhole (29).

With the constitution described, when the water that flows down the drain (4 or 5) reaches the water passage selector (7), it fills the peripheral chamber (11) and its temperature is detected by the probe (14). When this temperature is below a preset value, the actuated valve (13) derives the flow passage to the mouth (17) leading to the general downpipe (6). If the probe (14) detects that the water filling the peripheral chamber (11) is at a temperature higher than the predetermined value, the actuated valve (13) derives the flow through the mouth (16) towards the recovery facility thermal (19). In the event that in this situation a stopper descended through the downspouts (4 or 5), due to the mass and rate of descent thereof, its fall would continue through the perforated section of the entrance (9) of the siphon until reach the exit section (10) and from here, through the conduit (30), figure 1, the general downpipe (6) that leads to the drain.

The thermal recovery installation 819) can be constituted by a tank (31) in which the hot water supply pipe (18) flows through a particle retention filter (32). Inside the tank (31) a coil (33) is housed through which the clean water to be heated is circulated. The tank (31) can have internally available cleaning diffusers (34), an upper overflow (35) and a lower vacuum mouth (36). In addition, the tank (31) can have a temperature probe (37) installed. Figure 1 includes other thermal recovery installations that could be used in the recovery system, such as a plate exchanger, a tubular exchanger (38).

As a possible execution variant, the installation could include a single step selector installed in the downspout (6), to which the water from the downspouts (4 and 5) is conducted. In any case, the installation of the system of the invention will only require the necessary step selectors (7) to be inserted in the corresponding descents, an operation that can be carried out without the need to carry out works in the building structure.

The system of the invention is applicable to both single-family homes and blocks of homes, buildings and offices, hospitals, etc.

Claims (6)

5 10 fifteen twenty 25 30 ES 2 535 875 Al 1. - System for the recovery of heat from sewage, characterized in that the set of wastewater, including gray and black water, is passed before being sent to the general drain, through a water passage selector waste that is composed of a siphon, whose entrance section is surrounded by a peripheral chamber, with which it is in communication through holes or slots made in the wall of said section, whose chamber has an auxiliary outlet that is located at lower height than the siphon outlet and has an actuated valve mounted that controls the passage through this auxiliary outlet, depending on the temperature of the water contained in the peripheral chamber, diverting the water to a heat recovery system when said temperature it is greater than a preset value, while when it is lower than this value it deflects the passage towards the general drain. 2. - System according to claim 1, characterized in that the peripheral chamber is located around the entrance section of the siphon at a lower height than the exit section of said siphon. 3. - System according to claim 1, characterized in that the inlet section of the passage selector is in prolongation with the conduction of general wastewater discharge. 4. - System according to claim 1, characterized in that the actuated valve is activated by a thermal probe mounted in the peripheral chamber. 5. - System according to claim 1, characterized in that the auxiliary output is of equal or smaller section than the siphon outlet. 6. - System according to claim 1, characterized in that the holes or grooves that the siphon inlet section together with the filler filler material of the peripheral chamber constitute a filter system intended to prevent the passage of solids from said inlet section towards the auxiliary output of the peripheral chamber.