AU3314699A

AU3314699A - Pond waste extractor

Info

Publication number: AU3314699A
Application number: AU33146/99A
Authority: AU
Inventors: James Massard
Original assignee: RABSNEAD Pty Ltd
Current assignee: Rabsnead Pty Ltd
Priority date: 1998-06-03
Filing date: 1999-06-02
Publication date: 1999-12-16

Description

P/00/01i1 Regulation 3.2

AUSTRALIA

Patents Act 1990 .0 0 *o.

00 0*0.

*5 0

ORIGINAL

COMPLETE

SPECIFICATION

STANDARD

PATENT

Invention Title: "POND WASTE EXTRACTOR" The following statement is a full description of this invention, including the best method of performing it known to us: 2 THIS INVENTION relates to the treatment or cleaning of the bottom of ponds and the like, and, in particular, to the collection of the sludge which builds up at the bottom of ponds, such as are used in aquaculture, more particularly ponds for the raising of prawns and like type organisms.

Aquaculture involves intensive rearing of an organism.

Where this is a ponded situation, the pond bottom is the repository of excreta, and, additionally, planktonic matter, which builds up to contaminate the pond water. A report by Dr Paul Smith in Australian •o o00: 10 Fisheries, December 1993, holds that water quality is 'directly influenced by the sediment on the bottom of ponds'. That sediment is 'a black smelly mud' and it is composed in smaller part of uneaten food, of excreta, and, mainly of dead plankton sinking to the bottom.

The usual manner by which to deal with the sediment is to drain the •eo° pond, dry the bottom, and scrape away the sediment. Clearly the draining and drying is effectively non-productive down time for the l pond. It would be better to remove the sludge without draining. A regular cleaning without draining to keep the pond continuously productive would be desirable.

There is equipment by which to lift sediment, which equipment is typically put into use in clearing waterways. Particular apparatus is scaled to lift bottom material from lakes, ponds and lagoons. The usual dredge employs an hydraulic lift, typically coupled 3 with a work head which agitates the bottom, lifting sediment into a fluid flow, directing it to a settling tank. The operation of this style of equipment clouds the water with sediment, and this raised sediment may have a deleterious effect on life in the ponds.

It is an object of the invention to treat the bottom of bodies of water such as aquaculture ponds by a means which enables treatment, cleaning or clearing, without draining the catchment or waterway, or in such a manner that the life forms being reared might oo.: be able to remain in the pond without suffering serious harm or 10 without a serious loss in productivity. Other objects and various 9 advantages will hereinafter become apparent.

The invention achieves its object in the provision of a pond bottom treatment means including: an open bottom housing; 99°9a flow inducer by which to induce, in use, a flow from the housing, to lift or entrain biological and like type material from the bottom; and piping carrying the flow from the housing to a collection point. In this specification reference to a pond is to include dams, lagoons, reservoirs, and other like type bodies of water used in aquaculture. The open bottom housing is any means which is operable to allow production of a localised flow at the pond bottom 4 with the flow and entrained material able to be directed to some predetermined location. A flow inducer is any means operable to induce the requisite flow in the open bottom housing and includes injectors.

The bottom treatment means of the invention is ideally operated inside a hood or enclosure, ideally fitted at a trailing edge with means adapted or operative to smooth or compact the material forming the base or bottom of the pond as the removal means passes. Pneumatic lift of water within the hood is effected by °ooo° 0 injection in manner to cause a flow in ducting to the surface and up into a settling tank, and, ideally, the pneumatic lift is preferably coupled with injection of air into the pond bottom to more effectively entrain what sediment exists.

The invention also provides a pond bottom treatment method comprising: a. establishing a flow over the pond bottom by injection of an air/water mix to an open bottom housing and ducting the flow with entrained sludge to a collection point.

The pond bottom treatment method ideally additionally uses pressurised air which is preferably supplied to injectors to inject directly into the pond bed to create an airflow in the material of the pond bed.

The invention will now be described with reference to a preferred embodiment which is shown in the accompanying drawings in which: FIG. 1 is a perspective view showing the major components of equipment implementing the invention; FIGS. 2, 3 and 4 are side elevation, plan view and rear elevation, respectively, of the equipment of FIG. 1; FIG. 5 is a schematic representation of the air flow which may exist in the equipment of FIGS. 1 to 4; FIG. 6 is a perspective view of a module employed in 10 the work head to equipment as seen in FIGS. 1 to 5; and *oCFIGS. 7 to 9 are detailed views of the module of FIG. 6.

S. In FIG. 1 is seen a suitable vessel or water craft which may be used to traverse or move a work head, an open bottom housing, or pond bottom treatment means 11 over the base or bottom of a pond, which, in operation can be effective to work the o bottom and/or entrain or lift sludge or sediment, by means of a flow inducer, via or through ducting or piping 12 to inspection tanks or containers 13, with overflow therefrom flowed or passed by a pipe or tube 14 to a return duct or tube 15 which can be operative to pass or flow water back to the bottom at 16. The work head 11 might be lowered or dropped to the bottom, off or from, ideally, a boom 17 on a cable 18. The supporting craft may be driven or powered by propulsion means or thrusters such as 19. The work head 11 may be 6 assembled from parts or modules 20, ideally with a rearward or trailing compacting or smoothing blade or flap 21. Each module may itself be a two part assembly or construction with piping or ducting 22 back to the rigid piping 12 and thereby to the inspection tanks 13.

In FIGS. 2, 3 and 4 is seen side, plan and rear views of the craft of FIG. 1 and its bottom cleaning or clearing mechanisms.

In addition to the rear mounted propulsion 19, bow thrusters 23 may be added to enable better control of the craft. On ponds, in wind, the craft may be blown off course meaning that the bottom may be given o..

10 an uneven treatment. Extra levels of control of position will enable .improved operation. Various other systems, cable, etc, as are known to those skilled in the art, might be used to control progress of the craft. Control may be from a console 24 with an operator positioned seated at 25. Forward of the console might be positioned a preferably diesel powered compressor 36 with storage tank 27 for use in powering the craft and/or for use in the bottom cleaning process.

In FIG. 5 is seen a schematic representation showing a flow pattern which might be established in an open bottom housing by the apparatus or equipment during operation. An air/water mix may be delivered or injected via piping at 28, at typically 11 psi, through typically a cluster of four 13 mm pipes which are preferably clustered with effluent pipes 31 (typically a cluster of four aluminium 7 mm diameter pipes). The air water mixture may be injected into housings such as 20 in FIG. 1 by a line 29 with flow back via line to effluent tubes 31 and the inspection tank 13 of FIG. 3. Additional to the above may be further lines or tubes, typically at 13 mm diameter directed or connected to each housing to deliver or convey pressurised air (typically at 15 psi) to injectors such as 34 fed by line 33 to create an airflow in the material of the pond bed.

In FIG. 6 is seen a housing, in two portions 35,36, with respective effluent outlets 37,38. An air pump 39 may be operatively 10 associated with or fitted to respective outlets. A hitch or coupling *°*may be provided to enable or effect coupling of the work head to the craft, in use, and the housing may move or pass over the bottom on rails or skids 41,42. The housing may be fitted at the front with an assembly of agitators and/or injectors such as tynes 43 and needle breaks 44, described in greater detail below. Adjoining housings may coupled together by any means suited thereto such as hinges at A flat, blade or flap 46 smooths the bottom after passage of the housing.

In FIG. 7 is seen in transverse section, the pattern of flows within a housing such as seen in FIG. 6. Air flow at 47 is into the bottom at 48,49 at different depth, to entrain toxic gasses and pond waste. The main flow 50 in the housing may additionally work or scour the disturbed surface, lifting pond waste and toxic gasses to outlet 51 with air assist 52.

8 In FIG. 8 the housing 35 may have a manifold 53 attached to a front wall from which depend an array of injectors or needle breaks, preferably in two arrays, rows or banks 54,55, typically, respectively at 50 and 65 mm deep, to inject air at depth in the pond bottom.

In FIG. 9 is seen the housing 35 from the front, showing an ideal array, position and/or pattern of tynes 43 and needle breaks 54,55 across the front.

:io• In operation of the above device, the forwardly projected 10 tynes break up the substrate, cutting a furrow. The shorter following S. needle breaks cut deeper with the second longer needle breaks working even deeper. The fracturing of the bottom improves the effectiveness of the air injection in entraining gasses and sludge.

9.

Claims

1. A pond bottom treatment means including: an open bottom housing; a flow inducer by which to induce, in use, a flow from the housing, to lift or entrain biological and like type material from the bottom; and piping carrying the flow from the housing to a collection 10 point.

2. A pond bottom treatment means as claimed in claim 1 wherein the open bottom housing moves over the pond bottom on skids with an assembly of agitators and/or injectors such as tynes and needle breaks fitted at a forward edge and adapted at a trailing edge with a means which is operative to smooth or compact the material forming the base of the pond as the pond bottom treatment means passes.

3. A pond bottom treatment means as claimed in either one of claims 1 or 2 wherein a pneumatic lift of water within the open bottom housing is effected by injection of air into the open bottom housing via ducting from a surface vessel with flow of waste via the piping being to the surface and into a settling tank.

4. A pond bottom treatment means as claimed in either one of claims 2 or 3 wherein the pneumatic lift is coupled with injection of air into the pond bottom via injectors to more effectively entrain what sediment exists.

A pond bottom treatment means as claimed in any one of claims 1 to 4 wherein a thruster controlled vessel is used to move the open bottom housing over the bottom of the pond, lifting sludge or sediment via piping to inspection tanks with overflow therefrom 10 flowed by a conduit to a return tube which is operative to flow water back to the bottom. 99 9'

6. A pond bottom treatment means as claimed in claim wherein the open bottom housing drops to the bottom of the pond off a boom on a cable.

7. A pond bottom treatment means as claimed in either one of claims 5 or 6 wherein the vessel includes bow thrusters.

8. A pond bottom treatment means as claimed in any one of claims 1 to 6 wherein the open bottom housing is assembled from two or more side by side connected modules each with a trailing surface engaging blade with adjoining modules coupled together by hinges. 11

9. A pond bottom treatment means as claimed in claim 8 wherein each module is separately connected via respective manifolds with the ducting and piping. S. S S S *SSS *5 5 S

10. A pond bottom treatment method comprising: establishing a localised flow over a portion of the pond bottom by injection of an air/water mix to an open bottom housing located thereat: ducting the flow with entrained sludge to a collection point; and moving the point of localised flow over the bottom of the pond. 15

11. A pond bottom treatment method as claimed in wherein pressurised air is supplied to injectors and into the pond bed to create an airflow in the material of the pond bed.

12. A pond bottom treatment means substantially as hereinbefore described with reference to the accompanying drawings. DATED this Second day of June 1999. RABSNEAD PTY LTD By their Patent Attorneys FISHER ADAMS KELLY