AU2015100044A4 - Rainwater tank first flush and roof debris filter - Google Patents

Abstract

The rainwater tank first flush and roof debris filter is substantially a device that fits on top of a rainwater storage tank between the discharge end of a rainwater downpipe and the water access point of a rainwater storage tank. It can be used in conjunction with other commercially available components to allow clean filtered water to enter a rainwater storage tank. The rainwater tank first flush and roof debris filter device comprises: . a Base Unit; . a lift-out Debris Basket.

Description

Editorial Notes 2015100044 There are only 3 pages of description AUSTRALIA Patents Act 1990 PROVISIONAL SPECIFICATION RAINWATER TANK FIRST FLUSH AND ROOF DEBRIS FILTER The invention is described in the following statement.

RAINWATER TANK FIRST FLUSH AND ROOF DEBRIS FILTER Field of the Invention This invention relates to a rainwater tank first flush and roof debris filter device that, when used together with matching standard "off the shelf' items, allows a first flush and roof debris filter and collection system to be fitted between the discharge end of a rainwater downpipe and the water access point of a rainwater storage tank. Background to the Invention The initial rainwater runoff from a house roof can contain debris such as dust, dirt, bird droppings, leaves, etc that can make the water unsuitable for domestic use. After a period of rain, however, the roof can be considered "washed" and any further runoff can be considered "clean" and suitable for specific domestic use. Rainwater first flush systems typically comprise: . a reservoir of finite volume where the initial runoff from the roof is collected and dust, dirt, etc can settle out. . a bypass or overflow arrangement such that when the reservoir is full, water flows are diverted to a storage tank. . a system that allows the reservoir to slowly drain such that the reservoir is emptied once rainfall ceases. Water is only diverted to the storage tank if rainwater flows into the reservoir exceed the drainage flow out of the reservoir. Most rainwater first flush systems are incorporated into the rainwater downpipe system. This invention allows a first flush system to be retro-fitted between the downpipe discharge outlet and the water access point of the storage tank. Summary of the Invention The new device in accordance with this invention is a device that has: . a reservoir of finite volume that will collect the initial rainwater runoff, . a system such that, when the reservoir is full, rainwater overflow is diverted to a storage tank through slot filter, . a controlled draining system such that the reservoir will empty once rainfall ceases, . a means to filter out and collect roof debris for disposal. Description of a Preferred Embodiment of the Invention The invention and the use of the device can be better understood with reference to the following sketches (attached): . Sketch 1 shows the "Base Unit". It comprises the First Flush Reservoir and Slot Filters that allow "clean" water to pass into the storage tank. . Sketch 2 shows the "Debris Basket". It is similar to a sieve or colander, fits snugly inside the "Base Unit Reservoir" and is easily removed for emptying and cleaning. The top edge of the "Debris Basket" is marginally higher than the top edge of the "Base Unit Reservoir" such that the water level in the "Reservoir" is always lower than the top of the "Basket". This is to retain any floating debris within the "Basket". . Sketch 3 is a General Arrangement that shows: . the "Base Unit", with the "Debris Basket" positioned inside the "Base Unit Reservoir. . the "Base Unit Reservoir" connected with "off the shelf' tubing and valve such that "dirty" water is directed to waste. . how "clean" water is diverted to the storage tank The system is assembled as follows: i. the "Debris Basket" is fitted inside the "Base Unit Reservoir". ii. the "Base Unit" is placed centrally over the entry hole of the storage tank and between the downpipe discharge end and the storage tank. iii. the tubing, elbow and valve is assembled as shown in Sketch 3. iv. the tubing is inserted through the holes in the "Base Unit" as shown in Sketch 3, such that "dirty" water can drain from the "Base Unit Reservoir" through the tubing. v. the discharge end of the tubing is lead away to waste. An option for the tubing discharge is to connect it to the tank overflow system. The Sketches 1 & 3 show nominal 20mm tubing with holes to suit, but the tube sizing (and matching holes) can vary. The "Debris Basket" is easily removed to facilitate emptying and cleaning. The "Base Unit", and associated tubing, is also easily removed to facilitate cleaning and the tubing re-connected as necessary. Materials The "Base Unit" is preferably made from moulded plastic The Debris Basket is preferably made from moulded plastic or metal. While we have described herein particular embodiments for the "Rainwater Tank First Flush and Roof Debris Filter" and shown particular dimensions, it is further envisaged that other dimensions and embodiments of the invention could exhibit any number and combination of any one of the features previously described. However, it is to be understood that any variations and modifications can be made without departing from the spirit and scope thereof. Codac Engineering Pty Ltd 16 January 2015 Owen Griffiths