GB2440151A - An arrangement for recovering heat energy from waste water - Google Patents

Abstract

An arrangement for collecting grey water from within a building whereby the heat energy can be extracted, and that, along with the grey water can be recycled within the building, including a arrangement whereby this process can take place outside the building and be delivered into the building.

Description

<p>Improvements to grey water and energy recvcliiw There is a need to

reuse and recycle waste water and the heat energy it often contains from dwellings and other buildings.</p>

<p>Grey water i.e. waste water from baths, showers, washing machines, dishwashers etc can be re-used for flushing toilets, watering gardens etc. The improvements herein described and illustrated on drawing No. I are designed to capture and recycle this grey water and extract and use the heat energy it contains in the process.</p>

<p>A preferred embodiment in a dwelling is herein described with reference to drawing Nol.</p>

<p>A highly insulated tank, glass fibre, plastic, metal or similar (henceforth referred to as the tank) is situateI below the level of baths, showers, dishwashers, washing machines etc to collect grey water by gravity.</p>

<p>The level and positioning of this tank would be such that it can gather this waste water and that an overflow from the top of the tank, when the system is full, can discharge into an adjoining drain/sewer.</p>

<p>In new houses this maybe under the floor of, for example the kitchen, but in old houses this maybe problematic and it is envisaged that in old (or new houses) this tank may be positioned in the ground or below floor level outside the dwelling, In which case apart from the side and bottom of the tank.being highly insulated so would the top cover and connecting pipes.</p>

<p>The grey water from aforementioned appliances is plumbed together to flow into near the top of the tank 1. An outlet pipe 2 towards the bottom of the tank for reservicing toilet flushing initially, with surplus being decanted perhaps to an external water butt for external use which will be described in more detail later.</p>

<p>An overflow pipe 3 will decant into an adjoining drain.</p>

<p>To extract heat energy from the waste water a heating coil 4 or similar is positioned within and towards the top of the tank. This coil can then be plumbed together with a * radiator, heated towel rail or similar to reintroduce this heat back intO the house.</p>

<p>A complimentary arrangement for extracting this heat energy, should for instance, in hot water, the radiator or towel rail not be required, would be for this heat transfer to be used to pre-heat water entering the boiler or inunersion tank.</p>

<p>An arrangement whereby thermostatic valves cut off the water to the radiator/towel rail and allow water to the boiler or immersion tank to be preheated is envisaged.</p>

<p>Alternatively, a second heat exchanger 6 may be installed for this purpose.</p>

<p>The optimwn capacity of the tank will be dependent on the estimated volume of incoming water from the appliances, the amount of water needed for toilet flushing and other purposes, the object being to minimise any surplus water entering the drain/serr.</p>

<p>A arrangement of float switches, whereby, when the volume/level of water in the tank is approaching the overflow pipe, it can be pumped or decanted (if the tow tank heads are level) into a grey water holding tank for other purposes and only when that holding tank is full of water discharged into the drain/sewer is envisaged.</p>

<p>The arrangement for toilet flushing could be a pressure switch pump plumbed into the system, that when the toilet was flushed and pressure released the pump would activate and fill the cistern and deactivate when the balI-cock returned and pressure restored. Should the system run dry, a mains water back up to the toilets would be provided, or alternatively a stop cock arrangement 7, situated within and towards the bottom of the tank, introducing mains water, provided.</p>

<p>There will be a need to access the tank cleaning and maintenance. A sealed access plate 8 will be positioned in the head of the tank. Also a removable debris trap 9 could be provided to filter incoming grey water.</p>

<p>For ease of assembly and installation it is envisaged that the heating exchange coil or coils would be secured and plumbed into a sealed removable lid of the tank with the flow and return to the radiator/towel rail and/or boiler or immersion tank also plumbed to the top of this cover/lid.</p>

Claims (1)

1. <p>Claims i. An arrangement for collecting grey water from baths, showers

   and appliances whereby the heat energy and the grey water can be recycled within the building.</p>

   <p>2. An arrangement as in claim 1 wherein the arrangement can be situated within or below the building or outside the building.</p>

   <p>3. An arrangement as in claim 1 where the collection of grey water is gravity fed.</p>

   <p>4. A arrangement as in claim 1 where the heat extraction and recycling into the building is by convection.</p>

   <p>s. A arrangement as in claim I whereby water entering the boiler or immersion heater can be pre-heated from retained grey water.</p>