IE20080676A1 - A self contained and structurally self supporting high density modular aquaculture system - Google Patents

Abstract

An integrated 'flat pack' system which when assembled contains all the necessary components for a recirculation system. This system when operational employs a high density stacking arrangement central to which is a removable tank arrangement, an integrated sump, reservoir, water treatment facilities, pumping equipment and a self supporting building structure capable of acting as the envelope of a building.

Description

This invention relates to a self contained and structurally self supporting high density modular aquaculture system.

If one attempted to classify or divide up aquaculture systems (i.e. man made facilities / structures, for the controlled keeping, rearing, breeding and selling of fish*), wc could start by dividing these systems based on their location i.e. whether they are land based systems or water based systems (in water based systems we include sea systems such as salmon cages as well as lake and pond systems such as Koi pond systems. These systems are generally located outdoors and generally involve a large water mass). We could then go further and classify the systems in terms of whether they were salt water culture systems or non-saline water systems.

In relation to land based systems we could further classify systems in terms of whether they were 15 Flow through or Recirculation systems. A crude definition of a Flow Through system is one that relics on simply pumping water from a salt water or fresh water source into the tanks housing the fish and then allowing the water flow through the tank which eventually exits back to said source. In contrast, a recirculation system attempts to a greater or lesser degree to 'hang' onto or retain the input water and then recirculate it a number of times before finally releasing the water back to its original source. The logic behind such recirculation systems relies on achieving some or all of the following goals ; • Having better control of the input water in terms of quality, i.e. reductions in suspended solid loads, parasitic infections, diseases etc · Being more energy efficient than 'flow through' systems.

• Being a more ecological friendly system than ‘flow through** and therefore more likely to gain the appropriate permissions necessary from aquaculture regulatory bodies. ;yg£nT I S I ί? s ί <:Ί i ' Zi > * ' ',p .

• Offering more precise control of the water within the system, in terms of oxyi'&nTevels* and other desirable water parameters. t rn · Being better able to defend fish* against algal blooms and red tides.

• Having much greater control over waste water discharges.

• Having much better monitoring of waste discharges.

• Being more space efficient than “flow through** systems. tv; O O T> IE 0 8 ο 6 7 6 We will now focus on describing current recirculation systems, particularly their strengths and weaknesses, in order to effectively highlight the many ways in which our invention improves upon this traditional system.

In trying to provide the most humane, efficient environment for the fish they are trying to maintain, most modem recirculation systems grapple with a number of issues. Most recirculation systems arc typically comprised (although not exclusively), of the following components; 1) A Room - or number of rooms for housing the recirculation systems. These rooms can be simple structures just to keep birds and predators away or very elaborate modern buildings with air conditioning and insulated structures. The room or building which houses the recirculation system is invariably a separate self supporting construction to the recirculation system. 2) A Store of Water - or reservoir for topping up the system. This can be a reservoir capable of storing millions of litres of water or a more modest water store. The key feature is that the reservoir is a store of fresh makeup water for the entire recirculation system, i.e. it replenishes the system and refills it if necessary. The reservoir is typically filled at night to avail of cheaper electricity rates and can have a capacity to support the recirculation system from 24 hours to many weeks depending on its size. 3) A Sump - this is a critical component of the entire recirculation system as this is the place the pumping system draws its water from to recirculate. It is also the place that all waters within the system are designed to return to and where oxygenation, degassing, bio-filtering, screening, heating / cooling of the waters takes place (or adjacent to the sump). The sump is usually the lowest part of the entire system and for economic reasons a recirculation system attempts to utilise gravity feeds whenever and wherever possible. Sumps tend to be located in a plant room (generally where pumping and water treatment processes take place), or arc part of the recirculation culture room (which is generally separate from the tank system).

Sumps can be very substantial constructions, usually recessed into the ground as large tanks and so depending on the size of the system being constructed, can be very expensive build, operate and maintain. E.g. large aquaculture facilities typically have a sump room akin to an industrial sewerage treatment plant. 4) Water treatment equipment & systems - When fish respire, swim and eat in water, they generate by products. Typically, these by products are seen by recirculation farmers as waste. These can include carbon dioxide, nitrites, nitrates, ammonia, faces etc. Fish also consume and absorb a wide range of minerals and nutrients from the water they reside in and these also require careful monitoring and replenishment (The water should ideally contain a minimum amount of pathogenic organisms / toxins as well as a minimum amount of suspended solids, and should ideally be gin clear, for the animals to perform optimally). Furthermore, fish require their water to be of a certain temperature, oxygen and Phi level to θ 8 0 6 sustain ideal growth.

In order to achieve these many requirements most recirculation systems employ a series of water treatment processes such as ; ) A solids removal method. This can be a drum filter, belt filter, sand filter, bead filter, vortex chamber etc, or a combination of all of the above. The goal of these filters is to remove from the waters as quickly as possible : faeces, food and large particles of waste (generally above 120 micron). 6) A degassing system. This is usually some form of standing column media such as cooling tower fill or plastic string media, down which, the waste waters from the system trickles. Air is usually drawn into this system by means of a fan placed across this media, facilitating a gas exchange to replace the respired carbon dioxide with oxygen. Degassing towers also act as biological filters because bacteria invariably builds up on these towers and this bacteria is beneficial as it helps break down waste products in the water. 7) A bio filter and blower system. As mentioned previously, bio filters can be integrated into degassing columns, however, when bio mass loads from the fish increase within a system, typically bio filtration becomes a separate process in its own right. Bio filtration comes in many shapes and forms, but in the interest of brevity, a typical bio filtration unit consists of (I) a tank (with a controlled water level), where sump waters are discharged into and can then escape from, (2) high surface area beads (usually highly corrugated to maximise surface area) and (3), an air source (e.g. a blower) to boil the beads in the water. A blower can be integrated into the bio filter system or it can be separate. The purpose of the blower is to introduce oxygen into the systems waters. The blower usually requires a pipe system to deliver air cither into the bio filter or directly into the tanks. With air agitation, the beads in the water inevitably become colonised with large bacterial loads, and in turn these bacteria digest unwanted waste materials in the water. 8) A water sterilisation system. This usually consists of ultra violet light but can also be ozone. These systems sterilise some or all of the water load in the recirculation system in an attempt to reduce pathogens which could unchecked, overwhelm the animals in this enclosed system. 9) A water heating and/or cooling system. This maintains accurate and constant water temperature in the recirculation system.

) A protein skimming device. Protein skimmers are common to most recirculation systems because they provide an invaluable means of removing ultra fine particles and waste from the systems waters. These devices produce air bubbles, usually via a venturi device, which are inserted into the water stream entering the bottom of a filling column of water. This column is usually constructed of plastic and typically has a 'Swirl' flow pattern designed to best mix the millions of air bubbles into the water entering it. As the bubbles rise through the column and exit at the top, particles adhere themselves to the oxygen bubbles. The result IE 0 8 0 6 7 6 at the top of the open column is a 'frothing' effect. This froth will usually smell foul as a result of the water material being removed from the water. The foul froth is then removed from the main water via a continuous water jet (or sprayer) on the top of the cone shaped column. 11) A pumping system and pipe delivery system. Normally either submersible or centrifugal, pumps are the figurative heart of a recirculation system and are typically located within or around the sump area (discussed previously). Due to their importance, pumps are usually linked to float systems and alarms which control water levels, monitor the pumps themselves, and allow the appropriate discharge of waters.

Pipe work is normally made of HDPE or PVC and are the arteries and veins of a recirculation system. Large scale recirculation systems normally require extensive industrial scale piping particularly if the sump and water treatment systems are separate or away from the tank enclosures. 12) A PH buffering system. When fish breathe, they release carbon dioxide into the water. This repeated action changes the PH level of the water to acidic and this can greatly affect the fishes health. E.g. abalone and crustaceans can suffer from a syndrome known as shiny shell where by their protective shells literally dissolves off their backs as a result of the wrong PH levels. To prevent this happening, buffering of water via an alkaline solution is common to many systems and is normally done via some type of peristaltic pump arrangement or using a magnetic drive pump, capable of handling the highly corrosive alkaline solutions. 13) A Tank system to house the fish. Tanks come in all shapes and sizes with their design normally driven by the requirements of the fish they have to house eg. conical tanks, rectangular tanks, circular tanks, raceway systems etc. Irregardless of their design, each variation of fish tank attempts to meet (with varying degrees of success) the same objectives, namely , 1) The need to create a healthy living environment for the fish. 2) The need to facilitate efficient waste removal. 3) To facilitate easy and efficient feeding of the fish. 4) To facilitate the maximum amount of tank area or bed area relevant to the building footprint (intensification) and to be arranged in such a way so as to allow humans to work in and around these tanks safely and efficiently, i.e, a ergonomic work process.

Tanks commonly found in recirculation systems are single layered i.e. situated on the floor (not elevated), and are only occasionally arranged in tiers of two or higher. This is because elevated /£ 0 8 0 6 7 6 tanks make it extremely difficult and sometimes even dangerous for people to work around. E.g. to allow operators 'lean in' over the tank for cleaning, inspection or feeding is harder to do at a height then on the ground. Similarly, in their normal arrangement, tanks arc fixed in place (or rigid) and cannot be removed if in tiers. (We draw particular attention to this point as it is an extremely important differentiator between existing recirculation systems and the system proposed within this application). 14) A feeding system. In many aquaculture systems feeding is usually done via some form of mechanical dispensing system which dispenses pellet based or flake diet into the water in regular intervals. However, many aquaculture systems still rely on manual feeding.

Having been briefly introduced to recirculation systems, we should now look at the deficiencies of these systems so as to illustrate by contrast the advantages of the system described in this document N.B. This patent application seeks to focus on commercial aquaculture systems i.e. systems whose primary function and role is associated with the breeding keeping and rearing of fish for gain or reward as opposed to aquatic systems whose primary purpose is the housing of fish ostensibly for aesthetic reasons (e.g. domestic aquariums) and/or where the enclosure system itself is primarily used as a display unit. Thus what we are concerned about in this description is only systems which are utilitarian in nature i.e. where the systems aesthetics (if any) are purely incidental and of secondary importance.

In general, recirculation systems that are commissioned out of a desire for gain or reward tend to target a portion of the life cycle of the fish being cultured e.g. a larvae settlement system will usually have a separate design of tank and tank furniture customised (as far as the grower is concerned) to suit the requirements of that stage of the life cycle of that particular species. If the recirculation farmer wants to then on rear a species it would be the norm to have a separate recirculation system tailored for that purpose with different tanks, treatment systems etc. In other words, a system normally has to be customized not only for a certain breed of fish but also the different stages in that fishes life cycle. So for example it would not be unusual on a large scale aquaculture facility to have more than one type of aquaculture system present e.g. one targeting the larval cycle and one targeting the adult stage of the fish species. As one of its advantages, the aquaculture system described in this document, addresses this weakness and seeks to offer the grower operator a unified system to address most if not all of the commercial lifecycle of the intended species.

IE 0 8 Ο 6 7 6 DISADVANTAGES OF RECIRCULATION SYSTEMS To be fair to most if not all current recirculation systems» it must be said that they do a fair job of keeping their intended species alive. Suffice to say that if they couldn’t achieve this fundamental task then a treatise on their other merits or demerits, as the case may be» would be an academic exercise. However taken this as a given, current recirculation systems have numerous problems and disadvantages associated with their design and configuration. Three major design and implementation weaknesses are to be found to some degree in all recirculation systems currently available, namely; 1) Current recirculation systems are generally ergonomically* inefficient (*Ergonomics is the scientific discipline concerning the design of objects according to human needs). By ergonomically inefficient we mean that many of the tank and system designs used are not designed Io facilitate operators working in and around these systems quickly, safely and efficiently, e.g. Tanks are often too deep, too wide and have too many encumbrances within them to allow operators work safely. 2) C urrent recirculation systems are generally very space inefficient. By space inefficient we mean that many systems available show little regard as to how much space the system occupies or where the infrastructure of pipework, sumps and water treatment plants will be optimally located. Furthermore, the inefficiency of the tank configuration is such that few other industries would tolerate this wastage and lack of efficiency within these systems (inefficiencies we tender, that may have come from a mindset where traditional single species aquaculture facilities tended to be huge sprawling facilities in remote coastal regions, where site footprint wasn't a critical factor), i.e. where space wasn’t at a premium. 3) Current recirculation systems are to a greater or lesser degree : process inefficient. By process inefficient we mean that even modem recirculation systems employ poor methodologies in relation to key processes within the recirculation system. These include poor or deficient methodologies and or poor or deficient design in relation to ; • How the system is shipped to site, assembled and built (this also includes the construction of the external envelope of the building).

• How the system is erected and constructed (ground works, support services, drainage infrasiructure, cabling etc).

• How the system is commissioned.

• How the system is laid out within the building footprint i.e. has the maximum amount of culture area been packed into the least possible space ? • How the system is configured in terms of work flow.

• How water circulates within the system and how efficiently that water can achieve the IE 0 8 0 6 7 6 desired parameters necessary.

• How efficient the tank cleaning system is.

• How efficient the culture system is, in terms of handling requirements from the larval stage of the fish cycle, through to weaning, and then through to adult rearing and eventual harvesting / processing for sale.

• How efficient the actual tank space is in relation to each m2 of tank area and the fish’s requirements i.e. achieving the maximum possible density of animals contained within that space with respect to animal welfare and optimum growing conditions.

• How efficiently the system can contain a disease outbreak. (Large unified recirculation systems are exposed to parasites and fish infections which can wipe out the entire stock of a farm in one hit often due to the ‘commonality’ or unified nature of the system water reservoirs and sumps.) IE 0 8 ο 6 7 6 SUMMARY OF THE INVENTION This patent application for a self contained & structurally self supporting high density modular aquaculture system addresses in one unified system, the aforementioned disadvantages of traditional recirculation systems i.e. listed in paragraphs 1), 2) and 3) of DISADVANTAGES OF RECIRCULATION SYSTEMS above . This patent application declares as its inherent advantages, as being the antithesis of the problems identified with current recirculation systems in paragraphs I) 2), and 3) above, e.g. Paragraph 1) identifies the current problem of poor Ergonomics in current recirculation systems. This patent description claims and identifies excellent Ergonomics as one of its key or core advantages , etc.

This high density self contained and structurally self supporting modular aquaculture system (See fig. 1), (hereinafter known as the Cassette System in the interest of brevity) has certain key embodiments, namely; 1) The tanks in this cassette system are accessed from the front or side and not by leaning in overhead i.e. the main access method for the tanks in this system is by removing the tanks horizontal ly from their vertical stack one tank at a time, similar to taking a VHS tape from a front loading VHS player. This system does not envision culture tanks being worked on in situ within the confines of their tier and/or racking. To achieve maximum vertical stacking density this system requires extraction of each tank from its vertical stack, akin to pulling out a kitchen drawer horizontally to access the cutlery within (See fig. 2a). The system is therefore based on the premise of moveable (i.e. not normally fixed) tanks. 2) The number of tanks in a vertical stack can range anywhere from 2#, high up to an infinite number of tanks (limited only by engineering requirements and planning law restrictions.) 3) Tanks arc extracted from a vertical stack tor manual work to do with the tank. E.g. inspection, grading, harvesting etc. i.e. they are not normally worked on insitu. 4) Tanks slide in and out horizontally (See fig. 2a). This can be via a slide extension system (labeled A. See fig. 2b), roller devices (either on the tank itself or integrated into the shelving system), or passive slide devices.

) Multiple tanks as well as single tanks can be extracted at any time depending on what work is required to be carries out on them. (See fig. 3) 6) Tanks arc extracted into an available work space which we will describe as a corridor (Labeled A, see fig. 4), running the full length of the cassette system. 7) In this corridor would be located a telescopic electro-mechanical or mechanical table lift ΙΕ ο 8 ο 6 7 6 platform (Labeled C, See fig. 5). This table platform would allow an operator (Labeled B, See fig. 4 & lig.5) or multiple operators elevate and descend on a vertical stack and extract/replaee culture tanks as required (See fig. 5) (obviously operators could access tanks at ground level without the need for a table lift). This table lift would be fully mobile within the cassette corridor and tanks could be accessed from either side of the cassette corridor. 8) Vertical stacks of tanks are so arranged that there is a minimum amount of space between them vertically. Vertical clearance between tanks is only so much as allows a tank to be extracted without interfering with the tank above and below it. 9) The tanks or cassettes would receive and discharge their water from services and pipework integrated into the racking system.

) All the components of the system are so designed so that they are easy transport and containerisation efficient. The cassette system is modular in design, fiat packable (similar to the flat pack furniture principle) so that the basic racking, tank and water treatment system is repeatable continuously depending on the biomass of animals being required for production. 11) Common components exist throughout the system in terms of uprights, cross members, tanks, fittings, pumps etc. 12) A reservoir is built longitudinally along the top of each rack system to provide top up water for the sump (Labeled D, See fig.6) 13) The sump similar to the top up reservoir is again located within the footprint of the rack and is located at the bottom of the rack (Labeled E. See fig.7). Running through the sump is an air pipe as part of the bio filter (Labeled F, See fig.7). Integrated into the sump (at the end or midpoint) would be the pumping system (Labeled G, See fig.8), protein skimmers (Labeled H, See fig.8), degassing system, UV treatment, bio filter, other water treatment facilities (See fig.8) and aeration facility (Labeled I, See fig.8), mentioned previously. 14) Within the modular racking is contained the degassing column mentioned previously, i.e. integrated into the racking.

) The cassette system is self supporting and where required can be clad directly with a wall (Labeled A, See fig 1) and roof system (Labeled B, See fig.l) i.e. the racking acts as a self supporting industrial building structure (See fig.l) 16) The cassette system would have a fully integrated PH dosing system and integrated automated feeding system. 17) Within the modular system, due to the isolation of system waters, as being specific to that module natural disease containment system is created. As the reservoir, sump and water treatment is specific to a defined cassette rack a disease outbreak will be contained within that cassette rack and should not easily spread to others cassette racks within the complex. As the reservoir, sump and water treatment is specific to a defined cassette rack a disease IE 0 8 0676 ίο outbreak will be contained within that cassette rack and should not easily spread to other cassette racks within the complex.

Claims (6)

1) A high density modular self supporting aquaculture recirculation system with integrated water delivery system, integrated cassette or cartridge tank arrangement, integrated work corridors, integrated sump, integrated header tank /reservoir system and some or all of the water treatment processes required to sustain the fish integrated within the confines of the modular racking.

2. ) A modular system according to the previous claim which is complete in the extent and nature of its components in that it does not require the construction of ancillary sumps, reservoirs, and buildings to sustain and farm the intended species of fish. 3. ) A cassette system according to the previous claim in which the primary method of access to the cassette tank is by extraction of that tank from its vertical stacking drawer arrangement, in a horizontal direction, accessed either from the ground level or above ground level by the use of extraction equipment.

3) An extraction system according to previous claims which when accessing tanks above normal ground level access heights would use a mobile telescopic platform arrangement to facilitate operators reaching the required levels in order to access the tanks and the fish within them.

4. ) A modular racking system according to previous claims which would be self supporting and capable of having the exterior surfaces of said racking/shelving receive a wall cladding, roofing and door system so as to allow the cassette system assume the dual role of life support system for the fish contained 'within* and a building system 'without'.

5. ) A modular system according to previous claims which has as core to its design and implementation the ability to isolate the principal vector of disease i.e. water, which is contained and recirculated within the specific cassette module and cannot contaminate other cassette modules within the system as a whole.

6. ) A modular system substantially as described with reference to the drawings.