GB2491300A

GB2491300A - Service water usage system driven by drinking water

Info

Publication number: GB2491300A
Application number: GB1215783.0A
Authority: GB
Inventors: Ulrich Ehlert
Original assignee: SPINFLOW GmbH
Current assignee: SPINFLOW GmbH
Priority date: 2010-02-22
Filing date: 2011-01-12
Publication date: 2012-11-28
Anticipated expiration: 2031-01-12
Also published as: DE102010008840A1; DE102010008840B4; GB2491300B; GB201215783D0; WO2011101070A1

Abstract

The invention relates to a service water system, comprising a sunken reservoir (4) and an elevated tank (8), and further comprising a pump (12) for delivering the service water into the elevated tank (8), wherein the pump (12) is connected on the driving side (13) to a drinking water pipe (6) and when drinking water is withdrawn, said pump is driven by the flowing drinking water.

Description

PLANT FOR USING UNPROCESSED WATER HAVING A DRINKING WATER DRIVE

The present invention relates to a plant for using unprocessed water having the features of the pre-characterising clause of claim 1.

The use of unprocessed water, for example in the form of rainwater, is now generally accepted for flushing toilets, for operating washing machines and for watering gardens. In Germany, a cistern which is arranged in the ground or in the cellar of a building is generally used for storing the unprocessed water.

The unprocessed water is then conveyed by means of a pump into a pressurised storage container from which it can be removed. Such pressurised storage containers are integrated in main water works or arranged as so-called air vessels downstream of a pump. The availability of drinking water and electrical power is ensured with a high level of operational reliability so that the downtimes for both water supply systems are negligible.

However, there are also regions in which a storage container for drinking water or unprocessed water is arranged on the top floor or above the roof of a building in order, even in the event of a failure of power and drinking water, to provide a water supply which can be removed owing to its hydrostatic pressure alone.

The disadvantage of such unprocessed water containers located in high positions is that the unprocessed water is conveyed into the reservoir which is arranged in an elevated position by means of electric pumps which use a considerable amount of energy.

An object of the present invention is therefore to provide a plant for using unprocessed water which has an unprocessed water reservoir at the top and in which the use of electrical energy is generally reduced. This object is achieved with a plant for using unprocessed water having the features of claim 1.

Since the pressure increase pump is driven by means of water and the pump is arranged with the drive side thereof in the drinking water supply pipe, each time drinking water is removed the hydraulic system of the pump is activated and conveys unprocessed water from a collection container located in a low position into a high container. The resultant pressure loss in the drinking water pipe is low.

The pressure increase pump is preferably arranged in the domestic water connection between the water meter and a pressure reduction valve so that the pressure loss owing to the drive does not lead to a pressure drop in the building supply. Completely uncontrolled operation of the plant is possible when there is provided an overflow of the high container which leads into the low cistern. There may also be provision for a drinking water backfeed to be provided for the high container which, when the level of unprocessed water is low, ensures the availability of water in the high container and optionally compensates for the lack of unprocessed water backfeed in the event that the pressure increase pump may not have run for a sufficient length of time.

Embodiments of the invention are described in greater detail below with reference to the drawings, in which: Figure 1: is a schematic illustration of a plant for the use of unprocessed water with rainwater and a high container and a drinking water backfeed; and Figure 2: shows the plant according to Figure 1 with an additional electrical control and monitoring system.

Figure 1 is a schematic illustration of a building having a plant for the use of unprocessed water. The building has a roof 1 which is drained by means of a rain gutter 2 and a downpipe 3 into a cistern 4. The cistern 4 contains unprocessed water 5.

In the building there is provided in known manner a drinking water pipe 6 which extends to various tap locations 7 by means of installations which are not illustrated, such as pressure reduction devices and water meters.

A high container 8 is arranged on the top floor of the building. The high container 8 is filled with unprocessed water from the cistern 4 by means of a rising pipe 9. In order to convey the unprocessed water 5 in the rising pipe 9 from a removal device 10 to a tap location 11, there is provided a pump 12 which acts as a conveying pump for the unprocessed water 5. The pump 12 has a drive side 13 which is connected in series to the drinking water pipe 6.

The drive side may be constructed, for example, in the manner of a rotary valve or a vane-cell motor.

The pump 12 further has a conveying side 14 which is incorporated in the rising pipe 9. In this instance, there is provided in this preferred embodiment a positive-displacement pump which, when operated, necessarily conveys water from the cistern 4 into the high container 8.

The pump 12 is constructed in such a manner that, in adapting to the height difference between the cistern 4 and the high container 8, the required pressure can be built up. The pump is further provided with an internal or external non-return valve which prevents the rising pipe 9 from running empty when the pump 12 is non-operational. The drive side 13 of the pump is constructed in such a manner that, depending on the pressure present in the drinking water pipe, the unprocessed water can be conveyed reliably, without an excessively high resultant pressure loss in the domestic installation of the drinking water pipe. Thus, for example, the conveying volume of the conveying side of the pump 12 may be approximately 25% of the throughflow volume of drinking water at the drive side of the pump 12. This relationship is intended to be selected to be suitable in accordance with the local circumstances.

The high container 8 has some additional installations. There is provided an inlet chamber 15 into which the unprocessed water 15 is supplied via the tap location 11. The water level in the inlet chamber 15 is established by means of a floating gauge 16. If the water level becomes too low, there is actuated by means of the floating gauge a valve 17 by means of which drinking water is supplied to the high container 8 via a free outlet. On the one hand, the drinking water then supplements the unprocessed water supply in the high container 8, which is required, for example, for the operation of a toilet 18. On the other hand, the removal of drinking water also actuates the pump 12 via the opened valve 17 so that unprocessed water 5 is further supplied from the cistern 4 into the high container 8. This operating state may be required when the drinking water removal is too low to meet the requirements for unprocessed water in the high container 8.

The high container 8 is further provided with an overflow 19 which, when the level of unprocessed water in the high container is too high, directs the excess unprocessed water necessarily conveyed by the pump 12 back into the cistern 4 via an overflow pipe 20.

If the removal of unprocessed water exceeds the occurrence of rainwater or other unprocessed water, the water level in the cistern 4 may fall below the intake connection piece of the removal device 10. The pump 12 then draws air in. When more drinking water is removed, the pump 12 should preferably be prevented from running dry for a relatively long period of time. In order to achieve this in a simple and self-regulating manner, the high container is provided with a partition wall 28 which divides the high container S into the inlet chamber 15 for the unprocessed water and a second chamber 27. A connection with a small free cross-section allows slow balancing of levels in both chambers 15 and 27. To this end, in the embodiment, there is provided a sleeve 28 which is arranged slightly above the base of the high container.

If the floating valve 17 is now actuated owing to the falling water level in the high container 8 and in particular in the inlet chamber 15, drinking water runs via the free outlet 26 into the second chamber 17. The pump 12 now first conveys air. The water level in the inlet chamber 15 rises only slowly whilst the second chamber 27 is filled. The cross-section of the sleeve 28 in the connection between the chambers 15 and 27 is sized in such a manner that the overflow 19 is reached before the floating valve 17 switches off. Drinking water thereby reaches the cistern 4 and can be drawn in by the pump 12 at that location owing to the rising water level. The pump then conveys the drawn-in water into the inlet chamber 15, whereby the level increases rapidly at that location. The valve 17 then switches the drinking water backfeed off.

In this manner, long-term dry running of the pump 12 is prevented, even when no rain falls over a relatively long period of time or no other unprocessed water reaches the cistern 4.

During operation, the plant according to Figure 1 functions in such a manner that, in the event of rain, the rainwater flows from the roof 1 via the downpipe 3 into the cistern 4. Each removal of drinking water in the building necessarily activates the pump 12, whereby rainwater is conveyed via the rising pipe 9 into the high container 8. A removal of rainwater or unprocessed water from the high container 8 at the tap location 18 leads to a corresponding consumption in the high container 8 which in turn is compensated for by the pump 12. If more drinking water is removed from the tap locations 7 than is required to meet the unprocessed water requirements owing to the conveying capacity of the pump 12, the excess unprocessed water runs via the line 20 back into the cistern. If the removal of drinking water at the tap locations is too low to meet the requirement concerning the relationship of the volume of drinking water removed with respect to the conveying volume of the pump 12, drinking water is backfed via the valve 17 and the pump 12 is activated at the same time so that the high container 8 is filled with both drinking water and unprocessed water.

Figure 2 illustrates a plant which is similar to that of Figure 1. The same components have the same reference numerals.

In this variant, an electronic control system 21 is provided, which interrogates a filling level sensor 23 via an electrical line 22. An additional filling level sensor 24 is arranged in the high container 8. The control system 21 controls an electromechanical valve 25 which feeds from the drinking water pipe 6 into a free outlet 26 on the high container 8.

The function of this electrical control system is similar to that of the floating valve 17 from Figure 1.

The electronic control system 21 monitors the water level in the chamber 15.

If this water level falls below a threshold value which is detected via the sensor 24, the drinking water backfeed valve 25 is opened. This supplies drinking water via the free outlet 26 into the second chamber 27 of the high container 8. In the normal operating state, the pump 12 is activated by the removal of drinking water and unprocessed water 5 is conveyed from the cistern 4 into the chamber 15 of the high container 8 via the rising pipe 9. The water level measured with the sensor 24 thereby increases. If a sufficient water level is reached in the container 8, the drinking water removal is switched off again via the valve 25. The control system 21 can identify a defect of the pump 12 if the sensor 23 indicates an adequate supply of unprocessed water 5 in the cistern 4, but the water level does not increase in the chamber 15 in the manner provided for with the backfeed valve 25 open.

This is established by means of a comparison of the time path of the sensor signals 23 and 24. If the pump 12 is defective, a warning signal is emitted.

On the whole, the unprocessed water utilisation systems according to Figures 1 and 2 make it possible to use unprocessed water from a rainwater cistern or another low-lying reservoir, in which no electrical pressure increase pump is required. The conveying capacity for raising the unprocessed water 5 to the high container 8 comes from the use of the pressure drop in the flowing drinking water in the pipe 6. In order not to reduce the water pressure level in the building, the drive side 13 of the pump 12 is preferably installed upstream of a pressure reduction device for the domestic water installation. The pressure drop at the pump 12 would then influence the admission pressure at the pressure reduction device, but not the pressure of the drinking water in the building itself.

Claims

CLAIMS1. Unprocessed water plant having a low-lying reservoir (4) and a high container (8), and having a pump (12) for conveying the unprocessed water into the high container (8), c h a r a c t e r i s e d i n t h a t the pump (12) is connected at a drive side (13) to a drinking water pipe (6) and is driven by the flowing drinking water when drinking water is removed.
2. Unprocessed water plant according to claim 1, characterised in that thepump(12)isarranged in a domestic water connection between a water meter and a pressure reduction valve.
3. Unprocessed water plant according to either of the preceding claims, characterised in that thereisprovidedan overflow of the high container (19, 20) which is guided into the low-lying reservoir (4)
4. Unprocessed water plant according to any one of the preceding claims, characterised in that adrinkingwaterfeedis provided for the high container.
5. Unprocessed water plant according to any one of the preceding claims, characterised in that thereisprovidedan electronic control system (21) which monitors the filling level of the reservoir (4) and the high container (8) by means of sensors (23, 24).