[0001] The invention pertains to a system for storing and distributing water, the system
comprising a water tank having a fresh water inlet, a collected water inlet, and a
main water outlet; a fresh water conduit connected to the fresh water inlet; and a
main drain connected to the main water outlet, wherein the system does not have a
water tank bypass connecting the fresh water conduit to the main drain.
[0002] It is getting more and more important to reduce the weight of all components on vehicles
such as trains. In vehicles with sanitary facilities, there are two components whose
weight has a big contribution to the total weight of the vehicle, namely the fresh
water tank and the waste water tank.
[0003] At the same time, it is required to have more autonomy of the sanitary facilities
between filling operations of the fresh water tank, and especially between emptying
operations of the waste water tank. Higher autonomies result in bigger tanks, while
of course the weight and volume of the equipments increase.
[0004] In vehicles with the usual sanitary facilities, fresh water is used both for the
wash basin and the toilet bowl. For every use of the sanitary facilities, 0.4 (aprox.)
liters are used on the wash basin and 0.4 (aprox) liters on the toilet bowl (0.2 effluent
evacuation + 0.2 after cleaning).
[0005] In more recent sanitary facilities for vehicles, thanks to a grey water recovery
system, the water used on the wash basin is re-used on the toilet bowl, and therefore,
less quantity of water is required for the autonomy requested. The size of fresh and
waste water tanks can be then optimized taking into account the recovery operation.
Less fresh water is needed to cover the basin and bowl functions (smaller fresh water
tank), and so less water will be also kept with human effluents (smaller waste water
tank). The system allows reducing the size of the tanks and the weight on the vehicle.
[0006] Figure 1 shows a known sanitary facility with a grey water recovery system. These
facilities are currently implemented in the Euro tunnel shuttles.
[0007] Figure 1 illustrates the sanitary facility 100 of a railway carriage. The main components
of sanitary facility 100 are a main fresh water tank 102, an intermediate fresh water
tank 104, a wash basin 106, a toilet bowl 108, a waste water tank 110 and a grey water
tank 112. The grey water tank 112 is used to recover the water coming from the wash
basin 106 to flush the toilet bowl 108. The sanitary facility 100 comprises three
filters 114 to 118. The first filter 114 is located between the wash basin 106 and
the grey water tank 112, the second filter 116 is located inside the grey water tank
112, and the third filter 118 is located between the grey water tank 112 and the toilet
bowl 108.
[0008] A major concern with this and other known sanitary facilities is fresh water contamination.
[0009] Accordingly, it is an object of the present invention to provide a water storage
and distribution system with improved protection against fresh water contamination.
[0010] More precisely, in the context of a grey water recovery system where the fresh water
circuit and the grey water circuit are connected to a same water tank, it is an object
of the present invention to prevent contaminants present in the grey water circuit
from contaminating the fresh water stored in the fresh water tank.
[0011] These objects are achieved in a system for storing and distributing water of the
aforementioned type with a fresh water pollution prevention valve in the fresh water
conduit.
[0012] Preferred embodiments of the inventive water storage and distribution system have
one or several of the following features:
- a filter at the bottom of the water tank, wherein the collected water inlet leads
into said filter;
- the collected water inlet is arranged at the top of the water tank;
- the water tank further comprises a water evacuation outlet;
- the system is a greywater recovery system;
- the water tank comprises a contaminant spreading inhibiting air gap.
[0013] The invention also relates to a sanitary facility comprising the afore-mentioned
water storage and distribution system; a wash basin having a basin drain connected
to the collected water inlet; a toilet bowl having a bowl inlet connected to the main
drain; and a fresh water tank having an outlet connected to the fresh water conduit.
[0014] Preferably, the sanitary facility further comprises a wastewater tank having an inlet
connected to the water evacuation outlet.
[0015] The invention also relates to a vehicle, and in particular a railway carriage, comprising
the aforementioned sanitary facility.
[0016] The invention will be better understood when reading the following exemplary and
non limiting description in conjunction with the drawings, in which:
- figure 1 is a diagram of a prior art sanitary facility;
- figure 2 is a diagram of a sanitary facility according to a first embodiment of the
invention ;
- figure 3 is a diagram of a sanitary facility according to a second embodiment of the
invention.
[0017] Figure 2 shows a sanitary facility 200 according to the invention. The sanitary facility
200 is installed in a vehicle such as a railway carriage. The main components of sanitary
facility 200 are a fresh water tank 202, a wash basin 204, a waste water tank 206,
a toilet bowl 208 and a water storage and distribution system, namely a grey water
recovery system 209. The grey water recovery system 209 has a grey water input 210,
a fresh water input 212, a waste water output 214 and a flushing water output 216.
The grey water input 210 is connected to the drain 218 of wash basin 204. The fresh
water input 212 is connected to the outlet 220 of fresh water tank 202. The waste
water output 214 is connected to the inlet 222 of the waste water tank 206. The flushing
water output 216 is connected to the inlet 224 of the toilet bowl 208. The fresh water
tap 226 of the wash basin 204 is connected to the outlet 220 of fresh water tank 202.
[0018] The central element of the grey water recovery system 209 is a grey water tank 230.
The grey water tank 230 has a fresh water inlet 232, a collected water inlet 234,
a main water outlet 236, and a water evacuation outlet 238. A fresh water conduit
242 connects the fresh water input 212 with the fresh water inlet 232. A fresh water
pollution prevention valve 244 and a fresh water feed valve 246 are located in the
fresh water conduit 242. The collected water inlet 234 is connected to the grey water
input 210.
[0019] In the embodiment shown in figure 2, the collected water inlet 234 is arranged at
the top of the grey water tank 230 next to the fresh water inlet 232, similar to the
prior art solution shown in Fig. 1.
[0020] A main drain 248 connects the main water outlet 236 to the flushing water output
216. A non return valve 260 is located in the main drain 248.
[0021] It should be noted that the system does not have a water tank bypass connecting the
fresh water conduit 242 to the main drain 248.
[0022] The water evacuation outlet 238 is connected, via an evacuation valve 262, to the
evacuation output 214. A grey water filter 286 is fitted inside the water tank 230.
The filter 286 may be accessed via a removable filter cap, for filter cleaning. The
filter 286 is located at the bottom 290 of the water tank 230.
[0023] The operation of the sanitary facility 200 will now be described.
[0024] Grey water GW coming from the wash basin 204 enters the grey water tank 230 via the
collected water inlet 234. If a toilet flush is required, the grey water GW leaves
the grey water tank 230 through the main water outlet 236, transits through the non
return valve 260, and finally goes to the toilet bowl 208. If no grey water is available
in the grey water tank 230 for the flushing, the opening of the fresh water valve
246 is triggered such that grey water tank 230 is filled with fresh water coming from
the fresh water tank 202. This fresh water will then leave through the main water
outlet 236 for flushing the toilet bowl 208.
[0025] Thanks to the non return valve 244, no grey water GW can flow back from the grey
water tank 230 to the fresh water tank 202. Accordingly, bacteria and other pollutants
cannot cross from the grey water tank through to the fresh water tank. Preferably,
the non return valve 244 is designed according to the standard EN 1717.
[0026] If there is no bowl flushing while there are lots of basin uses, the grey water tank
230 will fill up. Thus, the opening of the evacuation valve 262 is triggered, so that
the content of the grey water tank 230 will be evacuated to waste water tank 206.
[0027] A second embodiment is shown in figure 3. In this figure 3, the elements similar
to those of figure 2 are referenced with the same numbers.
[0028] According to the second embodiment, the collected water inlet 234 is arranged at
the bottom of the grey water tank 230. Thus, this collected water inlet 234 reaches
into filter 286, so that the grey water GW is filtered and temporarily stored in the
grey water tank 230. An air gap 289 is present between the collected water inlet 234
and the fresh water inlet 232. This air gap 289 fills the space between the grey water
surface and the top of the grey water tank 230. The air gap 289 acts as a barrier
for contaminants in the grey water GW, which are thus prevented from reaching the
fresh water inlet 232. Accordingly, the air gap 289 can be qualified as a contaminant
spreading inhibitor.
[0029] In summary, the inventive water storage and distribution system and corresponding
sanitary facility stand out thanks to their small tank size and thus small weight,
their reliability and small number of components, the protection against fresh water
pollution, and the easy cleaning. A further advantage is the use of a single filter
for the whole system.
1. A system (209) for storing and distributing water, the system comprising:
- a water tank (230) having a fresh water inlet (232), a collected water inlet (234),
and a main water outlet (236);
- a fresh water conduit (242) connected to the fresh water inlet; and
- a main drain (248) connected to the main water outlet,
wherein the system does not have a water tank bypass connecting the fresh water conduit
(242) to the main drain (248),
the system being
characterised by a fresh water pollution prevention valve (244) in the fresh water conduit.
2. The system of claim 1, wherein the collected water inlet (234) is arranged at the
bottom (290) of the water tank (230).
3. The system of claim 2, wherein the water tank (230) comprises a contaminant spreading
inhibiting air gap (289) between the collected water inlet (234) and the fresh water
inlet (232).
4. The system of any one of the previous claims, further comprising a filter (286) at
the bottom (290) of the water tank (230), wherein the collected water inlet (234)
preferably leads into said filter.
5. The system of claim 1 or 4, wherein the collected water inlet (234) is arranged at
the top of the water tank (230).
6. The system of any one of the previous claims, the water tank (230) further comprising
a water evacuation outlet (238).
7. The system of any one of the previous claims, the system being a greywater recovery
system.
8. A sanitary facility (200) comprising:
- the system (209) of any one of the previous claims;
- a wash basin (204) having a basin drain (218) connected to the collected water inlet;
- a toilet bowl (208) having a bowl inlet (224) connected to the main drain; and
- a fresh water tank (202) having an outlet (220) connected to the fresh water conduit.
9. The sanitary facility of claim 8 with the system of claim 6, further comprising a
wastewater tank (206) having an inlet (222) connected to the water evacuation outlet
(238).
10. A vehicle, in particular a railway carriage, comprising the sanitary facility of claim
8 or 9.