NO345467B1 - Rotating plate freezer and a method for freezing a substance by means of a rotating plate freezer - Google Patents

Description

Technical field of the Invention

The present invention relates in general to a plate freezer, preferably but not exclusively, for freezing of a substance and/or liquid to be preserved and/or packed for storage. More specifically, the present invention relates to a plate freezer assembly for freezing a substance, such as biomasses, seafood or a liquid, such as water, either on a plant onshore or on board a vessel, the plate freezer assembly comprising a freezer plate unit of an assembly of a row of vertically arranged freezing plates, mutually interconnected arranged in parallel, separated and spaced apart in longitudinal direction, forming compartments accessible from the top and with confinement plates forming a bottom of the compartments, allowing the compartments to be filled with substance to be frozen and preventing the filled substance to slide out each freezer plate being provided with inlets and outlets for freezer agent, associated with supply and return lines and a manifold system.

The present invention relates to a method for freezing of a substance by means of a plate freezer assembly, the method comprising the following steps:

- filling each compartment of the freezer plate unit of the plate freezer assembly when it is in its filling position with the substance to be frozen from an intake or opening side on top of the compartments;

- circulating a freezer agent through the freezing plates of the freezer plate unit;

- establishing blocks of frozen substances;

- rotating the freezer plate unit to its emptying position upon completed filling and appropriate degree of freezing;

circulating a hot medium through the freezing plates for a short time and moving the freezing plates apart in a sideways direction, allowing the frozen blocks to move downwards, out of the compartments for transport to further handling and/or processing station, e.g. to a packing station.

Background of the Invention

Plate freezers for freezing of fish and other kind of seafood or biomass are well known in the art. In such plate freezers, a number of freezing plates are arranged and interconnected in parallel, forming chambers or compartments or voids between adjacent freezing plates, into which the seafood to be frozen is introduced for freezing. The number of parallel freezing plates and the distance between the plates varies. Plate freezers of different capacity and size are available, and the length of the row of plate freezer increases or decreases accordingly.

Plate freezers are traditionally used on board fishing vessels, where fresh fish, with or without first being disembowelled, are being frozen and where efficiency is desirable in order to increase the number of freezing cycles and thereby increase the capacity of freezing in order to freeze the fresh fish as soon as and fast as possible when hauled on-board.

The plate freezers are being loaded with biomass to be frozen into blocks, wherein the fish from a catch is being filled into the chambers or compartments between the freezing plates. The chambers or compartments are formed between adjacent freezing plates, an inlet or opening between the freezing plates, a bottom opposite the opening or inlet and sidewalls adjacent to the opening or inlet. The freezing plates are hollow in order to allow freezing agents to fill the cavity within each freezing plate. Each freezing plate is arranged a crosswise direction with respect to the longitudinal direction of the freezer and the freezing agent is circulated internally of the plate between an inlet and outlet, connected to a longitudinal manifold. The manifold extend in longitudinal direction, parallel with the freezer at one side of the freezer, a pair of hoses extending between the manifold and the inlet and outlet of each plate. Said manifold and hose system is arranged along one side of the freezer, opposite the side where the operator(s) introduces the fish into the space between adjacent freezing plates.

When the fish is frozen, the frozen blocks is unloaded from the freezer through a device for either pushing, lifting or releasing out of each individual compartment, either one by one or several blocks at a time. The blocks being placed onto transporting devices, typically trolleys, conveyor belts etc.. During the freezing stage, a bottom plate or a conveyor, which may be movably arranged in a vertical arrangement, is lifted up, serving as a bottom plate for each freezing compartment. During defrosting, the blocks are dropped down to the transporting device one by one for further transport. Alternatively, the block are either pushed or lifted, one by one, out of each compartment of the freezer and onto a transporting device for further transport.

The freezing process is initiated by circulating a freezing agent, preferably ammonia or CO2 gas, through the manifold and the hose system into the cavities of the freezing plates. When the biomasses has reached a desired temperature, preferably, but not necessarily, being thoroughly frozen, a warming agent, being the same gas acting as the freezing agent, but in a reversed cycle, is being circulated through the interior of the freezing plates for a short spell in order to warm the surfaces of the blocks sufficiently for loosening the blocks of frozen biomass from the freezing plates. Then, e.g. a bottom plate conveyor is lowered down, allowing the loosened blocks to drop out of the space between adjacent freezer plates, and transporting of the frozen blocks away from the plate freezer and to a packaging station and or a cold storage. When the last block in a row has left the transportation conveyor, the plate is lifted up in to contact with the lower end of the plates, and supply of a new batch can start.

Traditional plate freezer comprises one row of freezing plates and the capacity of the freezer is governed by the available longitudinal space of the room, thus limiting any increase in number of plate and thereby the freezing capacity. This is often at the sacrifice of accessibility for cleaning and maintenance between the freezing periods. In addition, at the sacrifice of optimal working conditions and thereby the Health, Environment and Safety (HES) of the operators. Further, the logistic of bringing the fresh substances of biomasses to the plate freezers and bringing the frozen biomasses to suitable further cold storage, transport etc. after completed deep-freezing are challenging i.e. with regards to available space for such activities. Better and more optimal working conditions and logistic comes on the other hand at the expense of the freezing capacity.

Traditional vertical plate freezers comprise more or less a stationary freezer where loading of fish into the various freezing compartments is possible only from one side, since the manifold and the hose system is arranged on the opposite side. In order to reach the compartments placed farthest away from the available positions of the operator, the operator have to take a leaning position over the freezer, which is an undesirable working position in regards to ergonomics and strain injury and is an extra undesirable working load under already heavy working conditions. In traditional vertical plate freezers, unloading of frozen blocks of biomasses has to be done by lifting the blocks up and out of the freezer, one by one or row by row, either by use of some kind of lifting equipment or by hand by an operator. Some plate freezers allow for letting the frozen blocks of biomasses to slide down to a means for transportation or conveyor after being released from the plate freezer. The blocks then have to fall down from a height onto this means for transportation or conveyors with a risk of breaking, falling over another block, etc.. Other plate freezers allow for letting the frozen blocks of biomasses to be pushed sideways out of the freezers onto a transporting device or followed by a lift by a robot or an operator further onto a transporting device.

NO 179384 relates to a method for filling and emptying a plate-freezing plant in which the goods to be frozen are packed in frames or the like, wherein a space between two freezing plates is opened by holding the freezing plate over the space, while the underlying freezing plates is lowered, whereupon the frames to be frozen are pushed into the space by an inserter and where these frames push out the finished frozen frames which are already in the space, characterized by the frames entering the space is pushed so far that the leading edge of the frames comes out of the edge of the freezing plate, thereby ensuring that the frames that are pushed out have come completely out of the gap, whereupon the frames to be frozen are pushed back and completely between the freezing plates and held in position in the space; Until the space is closed by raising the lower plate in known manner so that the frames are held in the space. There is also described a plate freezer adapted to the method.

WO 97/18424 describes a plate freezer consisting of a stack of horizontal freezer plates provided with spaces for goods, wherein the plates are vertically movable between vertical columns, and have an intake side for intake of goods and an outlet side for removal of goods placed at 180 degrees in relation to each other. The goods are frozen by placing them in a first freezer frame, which is passed to the intake side of the plate freezer, and into an extended space in the stack. The stack is lifted by means of a suitable lifting device, and the extended space is formed by bringing stoppers on the first and second frame carriers over contact surfaces connected with the columns and on into the stack, whereupon the stack is lowered so that the part of the stack which is located over the stoppers remains lying on the stoppers, pressing the stoppers down towards the contact surfaces.

GB 2275468 A describes an apparatus and a process for freezing and melting water, in particularly sludge from water treatment works. The document describes a plate freezer with an inlet for water containing sludge wherein the plate freezer comprises a series of parallel plates between which sludge is introduced and freezing means for freezing the sludge into one or more slabs and means for partially thawing the frozen slab(s) such as to release the slab(s) from the plates. Further the document describes a means for rotating the freezer for discharging the released slab(s) from between the plates

It is therefore a need for improved plate freezer where the freezing capacity may be increased considerably, where the required space for the freezing plant is not to any degree is increased, where the number of batches in a period may be increased, and where the working conditions for the operators filling the freezing spaces between adjacent freezer plate is substantially improved.

Summary of the Invention

The invention is based on the principle of arranging two separate freezer units in a back-to-back constellation, arranging the two units to rotate around a longitudinal axis in a controlled rotational manner, the weight of the assembled freezer being carried by a slew ring arranged at the two opposing end panels of the freezer. Moreover, the invention is also based on the principle of controlled and guided movement of the frozen biomass blocks downwards in a vertical direction, out from the freezer at any point in time during emptying of the frozen substances from the freezer.

A main object of the present invention is to increase the output capacity of the frozen biomass to be thermally treated without increasing to any degree the size and footprint of the freezing unit.

Another object of the invention is to provide a solution where it is possible to reduce the time taken from the frozen substance, such as seafood and biomass, leaving the freezer until the freezer being ready to receive a new batch of substance to be frozen.

Thus, it is an object of the present invention is to provide an improved plate freezer for freezing of biomasses with increased capacity and reduced time required for freezing a given volume.

Further, there is an object of the present invention is to provide a plate freezer for freezing of substance to be frozen into square blocks, where a new batch filling operation may be started prior to completed emptying process of the frozen objects.

Another object of the present invention is to provide a plate freezer for rapid and thoroughly freezing of substance to be frozen, increasing the freezing capacity and reducing the time required for freezing a given volume without increasing the footprint of the freezer to any degree.

A further object of the present invention is to provide a space saving freezer for optimized space utilization.

A still further object of the present invention is to provide a more compact freezer with at least double freezing capacity.

An even further object of the present invention is to provide a freezer that eases the handling and loading of biomasses and improves the HSE for the worker.

Another object of the present invention is to provide an improved unloading of frozen blocks of substance from the freezer onto a means for transportation.

Yet another object of the present invention is to provide an unloading of frozen blocks reducing the risk of breaking the blocks into pieces at unloading.

A further object of the invention is to provide a freezer plant where the working operations for the operator(s) are improved, reducing the body strain and stress on the operator(s), at least during the filling process.

A still further object of the present invention is to provide a freezer where the operator(s) more easily may sort the different type of species in a catch and in an enhanced way may have easy access to the various compartments of the freezer, securing that species of same type are put into same compartment.

A still further object of the invention is to simplify the freezer and still increasing its capacity.

Yet another object of the present invention is to provide a freezer with better access for cleaning and maintenance of the freezer.

The objects are achieved by a double rotating plate freezer and a method for freezing of biomass/seafood by means of a plate freezer as further defined by the independent claims, while embodiments, alternatives, modifications and variants are defined by the dependent claims.

In a first aspect, the present invention relates to a plate freezer assembly for freezing a substance, such as biomass or seafood. The plate freezer comprises at least one freezer plate unit being an assembly of a row of vertically arranged freezing plates that are mutually interconnected in parallel, forming compartments being accessible from the top allowing filling the compartments with substance to be frozen. The plate freezer being arranged with confinement plates forming a bottom of the compartments, preventing the filled substance to be frozen to slide out. The freezer plates are being provided with inlets and outlets for a freezer agent, associated with supply and return lines and a manifold system. The plate freezer assembly being characterized in that the freezing plates are separated and spaced apart in longitudinal direction and that the plate freezer is provided with devices allowing the at least one freezer plate unit to be rotated around a longitudinal axis between a filling position and emptying position.

According to the invention, the plate freezer assembly when in the filling position is arranged with the compartments of the at least one freezer plate unit pointing its intake or opening side upwards or inclined up to for example 0 to 60 degrees. The plate freezer assembly in the emptying position is arranged with the compartments of the least one freezer plate unit pointing its intake or opening side downwards.

According to the invention, the freezing plates may be arranged between an end panel at each longitudinal end of the plate freezer assembly and aligned in the longitudinal direction of the plate freezer assembly, with the manifold and supply and return lines being arranged on the end panels, at least on one longitudinal end of the plate freezer assembly.

According to another embodiment, the plate freezer assembly comprises at least two, separate, but integrated, freezer plate units, arranged in a back-to-back configuration in the longitudinal direction.

According to a further embodiment of the plate freezer assembly, the vertical and parallel freezing plates are longitudinally arranged in the freezer plate unit between the end panels.

The at least two freezer plate units may be pointing their intake or opening sides in opposite directions.

According to a variant of the present invention, the plate freezer assembly in the filling and/or emptying position may be adapted to be lowered or lifted in vertical direction by a means for lifting and lowering.

According to the invention, the plate freezer assembly may be adapted to switch between the filling and emptying position by a device for rotating the freezer plate unit.

According to a variant of the present invention, the plate freezer assembly may have an integrated device for lifting or lowering, enabling a lifting of a guiding and transporting device 130 or a support board 131 emptying frozen substance when released from the compartments.

According to an embodiment, the plate freezer assembly may have an integrated device for lifting or lowering of the plate freezer unit when being in the emptying position for the frozen substance.

The device for rotating may be a gear rim rigidly connected to one of the end panels.

The device for lifting and lowering may be an actuator arrangement.

According to the invention, the freezing plates may also be adapted to be parallelly displaced by increasing or decreasing the mutually distance between the freezing plates in order to ease loosing of frozen blocks and/or to increase or decrease the volume of the compartments.

In a second aspect, the present invention relates to a method for freezing of a substance by means of a plate freezer assembly, the method comprising the following steps;

- filling each compartment of the freezer plate unit when in its filling position with the substance to be frozen from an intake or opening side on top of the compartments;

- circulating a freezer agent through the freezing plates of the freezer plate unit;

- establishing frozen blocks of frozen substances;

- rotating the freezer plate unit to the emptying position upon completed filling and appropriate degree of freezing;

circulating a hot medium through the freezing plates for a short time and moving the freezing plates apart in a sideways direction, allowing the frozen blocks to move downwards, out of the compartments for transport to further handling and/or processing station, e.g. to a packing station.

According to the invention, the method may further comprise orienting of a back-to-back configuration of two freezer plate units of the plate freezer assembly, with the further freezer plate unit, with upwards open compartments, being in its filling position being filled with the substances to be frozen while the first freezer plate unit below being emptied; and then rotate the two freezer plate units, so that the first freezer plate unit is returned back to its filling position, ready for filling while the freezing and emptying of the second freezer plate unit is initiated.

According to a further aspect of the invention, the method may further involve the compartments filled with substances to be frozen being maintained in the filling position, until the substances to be frozen are sufficiently frozen to remain in the compartments and then rotating the compartments to the emptying position, whereupon the freezing process is continued till frozen blocks are obtained.

A major advantage of the present invention is that, in spite of a more or less doubled freezing capacity, i.e. increased volume/weight of biomass per time unit, the footprint of the freezer according to the present invention being substantially the same as a comparable prior art freezer.

Yet another advantage is that the loosening of frozen biomass/seafood of one row of filled compartments or chambers can be initiated while still freezing a last filled row of compartments or chambers. This allowing for filling the emptied row of compartments or chambers while loosening the frozen substance of e.g. biomass or seafood of the last filled row of compartments or chambers.

Another advantage is that the space saving freezer can release space for other activities or give optimized space utilization. Released space can be utilized for i.e. eased access for cleaning and maintenance, storing of residual raw material or releasing space for at least another one of the new plate freezer of the present invention. Released spaced can be utilized for eased handling and loading of seafood and also eased access for cleaning and maintenance improving the health, security and environment for the operator. Released space can also be utilized in regards to newbuilding or rebuilding of boats, for i.e. open up for increased capacity or new activities. With increased focus on utilization of residual raw material, released space can be used for storing of or processing of the residual raw material of the biomasses/seafood in order to use this in i.e. fish or animal feed, dietary supplements as i.e. omega-3 fatty acid, protein powder, etc., as ingredients in cosmetics or pharmaceuticals etc..

Another advantage of the present invention is that the system with the plate freezer allows for automated unloading of blocks of biomasses, the whole row in one turn.

Yet another advantage of the present invention is that the device for transport of frozen blocks can utilize space below the plate freezer, whereby the plate freezer can rotate/tilt the plate freezer into a position where the intake of one of the rows are pointing it’s intake for loading of biomasses down towards a means for transportation and whereby a surface/support board of the means for transportation or the means for transportation it selves can be lifted by a means for lifting either integrated in the means for transportation it selves or integrated in the freezer in order to be in a position close to or in an approximately immediate vicinity the intake for loading of biomasses. An option of lifting the means of transportation may be that the freezing plate units can be lowered down to a means for transportation. When the blocks of frozen biomasses is being released from the freezing plates, they are immediately resting on the support board of the means for transportation. Transported for further handling, i.e. packing, stacking, etc..

Another advantage of the present invention is that the plate freezer can be rotated/tilted while filling of biomasses, in order for better accessibility to compartments farthest away from the operator. Giving better accessibilities for the operator while filling biomasses into the compartments of the plate freezer.

Another advantage of the present invention is that the freezing plates of the plate freezer has been turned from a transverse position to longitudinal position and where the space, making displacement of the freezing plates while releasing the frozen blocks of biomasses possible, is decreased with regards to the number of parallel freezing plates necessary when taking a longitudinal position. The number of parallel freezing plates being decreased to approximately a third of the traditionally transversely placed parallel freezing plates, maintain the same volume/capacity for freezing of biomasses.

Yet another advantage of the present invention is better accessibility for maintenance, filling and cleaning by rotating/tilting the freezing plates of the plate freezer into appropriate positions between positions pointing the intakes of the rows either up or down, the intakes of each row situated in opposite directions.

Brief Description of the Drawings

In the following examples of embodiments of the invention shall be described in further details, referring to the accompanying drawings, wherein:

Figure 1 shows schematically and in perspective, a vertical plate freezer of prior art;

Figure 2 shows schematically and in perspective an embodiment of a rotatable plate freezer assembly according to the invention, showing two freezer plate units of freezing plates arranged vertically above each other, all in accordance with the inventive idea;

Figure 3a shows schematically a side view of the plate freezer assembly in a filling position ready for being loaded with substance to be frozen;

Figure 3b shows a side view of the plate freezer assembly in a tilted or rotated into another filling position for loading with substance to be frozen;

Figure 4a shows a side view the plate freezer assembly in process for being rotated 180 degrees from the filling position to an emptying position;

Figure 4b shows in side view the plate freezer assembly rotated 180 degrees from the filling position to an emptying position;

Figure 5a shows a side view of the plate freezer assembly, with the first or second freezer plate pointing its intake or opening side upside down, a guiding or transportation device in position below the plate freezer assembly, the guiding or transportation device or a support platform of the guiding or transporting device being able to be elevated towards the intake of opening side of the freezer plate unit;

Figure 5b shows a side view of the plate freezer assembly, frozen blocks of substance to be frozen exposed to a short period of warming up the freezing plates; and

Figure 6 shows a schematically and perspective view of the plate freezer assembly, wherein the frozen blocks is released and transported from the plate freezer.

Detailed Description of Embodiments disclosed in the Drawings

The following description of the exemplary embodiments refers to the accompanying drawings. The same reference numbers in different drawings identify the same or similar elements. The following detailed description does not limit the invention. Instead, the scope of the invention is defined by the appended claims. The following embodiments are discussed, for simplicity, with regard to freezing of biomass or seafood on board a fishing vessel, which may be used for catching i.e. pelagic fish to be frozen directly without being intermediate stored for example at line fishing vessels.

Reference throughout the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the subject matter disclosed. Thus, the appearance of the phrases “in one embodiment” or “in an embodiment” in various places throughout the specification is not necessarily referring to the same embodiment. Further, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

Figure 1 shows schematically and in perspective a horizontally arranged prior art plate freezer assembly 100 comprising a freezer plate units 110 with a plurality of vertical freezing plates 112 arranged in one rows. The plates 112 being arranged in order to define vertical compartments or chambers 111 for substance, such as seafood/biomasses, to be frozen into blocks between the vertical freezing plates 112. The plates 112 typically being hollow and made of aluminium and may be filled with a refrigerant being pumped and circulated within the plates 112. The frozen blocks of seafood/biomasses is upon completed freezing sequence released from the freezing plates 112 by means of a warm gas being circulated within the plates 112 in order to defrost the surfaces of the freezing plates 112, thus facilitating the release and removal of the blocks for further storage or transport.

Figure 2 shows schematically and in perspective an embodiment of a rotatable plate freezer assembly 100, the plate freezer assembly 100 comprises two freezer plate units 110. One single freezer plate unit 110 comprises the freezing plates 112 being vertically and parallel arranged with a number of freezing plates 112 arranged in a row. The two freezer plate units 110 shown possesses two different positions pointing in different and opposite directions. Traditionally, vertical plate freezer assemblies 100 as shown in Figure 1, the freezing plates 112 are being arranged transversely to longitudinal direction of the plate freezer assembly 100, the plate freezer assembly 100 of the present invention preferably arranges the freezing plates 112 vertically and in parallel in the longitudinal direction of the plate freezer 100. The space formed between the freezing plates 112 being divided into compartments 111 of suitable and adjustable lengths by means of movable spacers forming intermediate panels 123 and end walls or panels 115 in order to divide the substance to be frozen into blocks of suitable sizes.

The plate freezer 100 shown is in a filling position where a first freezer plate unit 110 is pointing the side with its intakes/openings 113 upwardly and ready for filling the compartments 111 with the substance to be frozen. The opposite second freezer plate unit 110 is arranged below the first freezer plate unit110, in a back-toback configuration in the longitudinal direction, with its side of intake or openings 113 of the compartments 111 pointing down in the opposite direction of the first freezer plate unit 110, being in an emptying position for blocks of frozen substance. A freezer plate unit 110 being arranged with confinements plates (not shown) at the opposite side of its intake or opening side 113, the confinement plates preventing the substance to be frozen from sliding out of the freezer plate unit 110. Two freezer plate units 110 arranged in a back-to-back configuration may share common confinement plates. The freezer plate units 110 are adapted to be rotated in order to switch or alternate between the loading compartments 111 of the two rows. An arrangement or device for rotating 117 is shown by means of a gear rim. The gear rim being fixed to a frame of the rotatable plate freezer assembly 100 and a movable/rotatable part of the gear rim being fixed to a connective arrangement of the two freezer plate units 110 at one of the two longitudinal ends 116 of the plate freezer 100. The arrangement or device for rotating 117 facilitating the rotation of the freezer plate units 110 in order to switch between the two rows of loading compartments 111, or to facilitate different and angled loading positions.

The plate freezer assembly 100 of present inventions showing two freezer plate units 110 of a number of parallel freezing plates 112, the plate freezer 100 is not limited to only two freezer plate units 110, it may be only one, but also three, four, etc. placed in different position, pointing in different directions, but preferably arranged at angles evenly distributed.

Figure 3a shows schematically a side view of the plate freezer assembly 100 in an initial phase, the compartments 111 of the rows being empty, in a filling position, ready for loading of substance to be frozen. The freezer plate unit 110 being in one filling position for loading of substances to be frozen. The plate freezer assembly 100 being filled with substances to be frozen following an initial freezing phase where refrigerant is being filled and circulated into cavities of the plates. The initial freezing phase lasts until the substance to be frozen is sufficiently frozen in order to be become stuck to the freezing plates 112, where the plate freezer 100 is thereafter turned/rotated in order to point it’s opposite second freezer plate unit’s 110 intake or opening side upwards, being in its filling position, and the first freezer plate unit 110 pointing the intake or opening side 113 downwards, upside down, being in its emptying position.

Figure 3b shows a side view of the plate freezer assembly 100, where the freezer plate unit 110 being tilted/rotated by the device for rotating 117 in order to gain a more efficient and ergonomically working position for the operator in an alternative or additionally filling position for loading, standing at a platform, not shown. The distance between the operator and the compartments 111 furthest away being decreased, and a preferred working position of the operator can be maintained, without unnecessary bending the upper part of the body, also benefitting in heavy working environments on board a boat, the boat stamping against the movable ocean/waves.

Figure 4a showing a side view of the plate freezer assembly 100, the freezer plate unit 110 being rotated to an emptying position of the first freezer plate unit 110 at the end of the initial freezing phase, to the position shown in Figure 4b.

Figure 4b shows a side view of the plate freezer assembly 100, the freezer plate unit 110 rotated 180 degrees from the filling position to the emptying position of the first freezer plate unit 110, the opposite second freezer plate unit 110 ready to be filled by the operator or automatically filled, pointing it’s intake or opening side 113 up. When the compartments 111 of the opposite second freezer plate unit 100 are filled with substance to be frozen also the hollow freezing plates 112 of the second freezer plate unit 110 are being filled with a refrigerant, starting the freezing process of the opposite row. The freezing process will continue in both the first freezer plate unit 110 and the opposite second freezer plate unit 110 until the substance to be frozen has reached a desired freezing temperature or being thoroughly frozen, where the substance to be frozen has being frozen into blocks of seafood/biomasses. The frozen blocks of biomasses in the first freezer plate unit 110, ready to be unloaded before the second freezer plate unit 110. An unloading process of the first freezer plate unit 110 can take place. Given the initial freezing process of the second freezer plate unit 110 is finished, the plate freezer assembly 100 may again be rotated and the first freezer plate unit 110 can again be filled while the freezing process of the second freezer plate unit 110 continues. This process can be repeated.

Figure 5a shows the plate freezer assembly 100, with the first freezer plate unit 110 (or second freezer plate unit 110) pointing its intake or opening side 113 upside down, in its emptying position. A guiding or transportation device 130, i.e. a trolley or a conveyer or other suitable means for transportation, being in a position able to be elevated up towards the intake or opening side 113 of the first freezer plate unit 110 (or second freezer plate unit 110), the guiding or transportation device 130 being elevated or a support board or platform 131 as part of the guiding or transportation device 130 may be elevated. In another embodiment of the present invention, the plate freezer assembly 100 may comprise an arrangement for lowering the freezer plate unit 110, pointing its intake or opening side 113 upside down, down to a guiding or transportation device 130 or a support board or platform 131 of a guiding or transporting device 130.

The guiding or transporting device 130 or the support board or platform 131 of the guiding or transporting device 130 is suitable for receiving the frozen block of biomasses after a short period of warming up the freezing plates 112 in order for the frozen blocks of biomasses to be released from the surfaces of the freezing plates 112, shown in Figure 5b. In order to enable release of the frozen blocks of biomasses from the plate freezer assembly 100, the hollow freezing plates 112 are being supplied with a hot/warm medium, i.e. a warm gas, for defrosting the surfaces of the freezing plates 112. The hot/warm medium enters the freezing plates 112 on the turned/rotated freezer, ensuring that the blocks do not stick to the freezing plates 112 during removal. For further supporting the frozen block of biomasses being released from the freezing plates 112 the freezing plates 112 may be opening up in order for the frozen blocks of biomasses to fall or slide gently down to the guiding or transportation device 130 or the support board or platform 131. The freezing plates 112 are opening up by a parallel displacement of the freezing plates 112, increasing their mutual distance about 3-5 mm. Thereafter the guiding or transportation device 130 being lowered down towards the bottom floor or the support board or platform 131 being lowered down to the guiding or transportation device 130 ready for being transported away from the plate freezer 100. When sufficiently defrosted, the blocks being released and fallen or slid down to the suitable guidance or transporting device 130 enabling transport of the frozen blocks of the first freezer plate unit 110 to an appropriate cold storage, packing, handling or transport as shown in figure 6. A rotation of the plate freezer 100180 degrees in order for the opposite second freezer plate unit 110 pointing its intake or opening/ 113 upside down is taken place. A new or an unloaded guidance or transporting device 130 will take place below the plate freezer 100, and the same procedure of de-freezing, releasing and transport of the frozen blocks, now of the opposite second freezer plate unit 110 to an appropriate cold storage or transport will be repeated. The process described in figure 2 through figure 6 is repeated for new freezing cycle of new blocks of biomasses.

The plate freezer assembly 100 or the guiding or transporting device 130 may comprise hydraulic lifting arms adapted to lower or lifting either the freezer plate unit 110, the guiding or transporting device 130 or support board or platform 131 into suitable positions for loading of seafood/biomasses, rotating for loading of the two freezer plat units 110 and for releasing of frozen blocks of seafood/biomasses onto conveyers or other suitable guiding or transporting devices 130 arranged below the freezer plate units 110.

Table 1

Claims (16)

Claims

1. A plate freezer assembly (100) for freezing a substance, such as biomass or seafood, where the plate freezer (100) comprises at least one freezer plate unit (110) of an assembly of a row of vertically arranged freezing plates (112), mutually interconnected in parallel, forming compartments (111), accessible from the top and with confinement plates forming a bottom of the compartments, allowing the compartments (111) to be filled with substance to be frozen and preventing the filled substance to slide out, the freezing plates (112) being provided with inlets (118) and outlets (119) for a freezer agent, associated with supply (121) and return lines (122) and a manifold system (120),

c h a r a c t e r i z e d i n t h a t

the freezing plates (112) are separated and spaced apart in longitudinal direction and the plate freezer assembly (100) is provided with devices allowing the at least one freezer plate unit (110) to be rotated around a longitudinal axis between a filling position and an emptying position.

2. Plate freezer assembly (100) according to claim 1, wherein the plate freezer assembly (100) when in the filling position is arranged with the compartments (111) of the at least one freezer plate unit (110) pointing its intake or opening side (113) upwards or inclined up to for example 0 to 60 degrees, and the plate freezer assembly (100) in the emptying position is arranged with the compartments (111) of the least one freezer plate unit (110) pointing its intake or opening side (113) downwards.

3. Plate freezer assembly (100) according to claim 1 or 2, wherein the freezing plates (112) are arranged between an end panel (115) at each longitudinal end (116) of the plate freezer assembly (100) and aligned in the longitudinal direction of the plate freezer assembly (100), with the manifold (120) and supply and return lines (121, 122) being arranged on the end panels (115), at least on one longitudinal end

4. Plate freezer assembly (100) according to any one of the claims 1 to 3, wherein the plate freezer assembly (100) comprises at least two, separate, but integrated, freezer plate units (110), arranged in a back-to-back configuration in the longitudinal direction.

5. Plate freezer assembly (100) according to any one of the claims claim 1 to 4, where the vertical and parallel freezing plates (112) are longitudinally arranged in the freezer plate unit (110) between the end panels (115).

6. Plate freezer assembly (100) according to claim 4 or 5, wherein the at least two freezer plate units (110) are pointing their intake or opening side (113) in opposite directions.

7. Plate freezer assembly (100) according to any one of the claims 1 to 6, wherein the plate freezer assembly (100) in the filling and/or emptying position is adapted to be lowered or lifted in vertical direction by a means for lifting and lowering.

8. Plate freezer assembly (100) according to any one of the claims 1 to 7, wherein the plate freezer assembly (100) is adapted to switch between the filling and emptying position by a device for rotating (117) the freezer plate unit (110).

9. Plate freezer assembly (100) according to any one of the claims 1 to 8, wherein the plate freezer assembly (100) has an integrated device for lifting and lowering, enabling a lifting of a guiding and transporting device (130) or a support board (131) emptying frozen substance when released from compartments.

10. Plate freezer assembly (100) according to any one of the claims 1 to 8, wherein the plate freezer assembly (100) has an integrated device for lifting and lowering of the freezer plate unit (110) when in the emptying position for frozen substance.

11. Plate freezer assembly (100) according any one of the claims 8 to 10, wherein the device for rotating (117) is a gear rim rigidly connected to one of the end panels (115).

12. Plate freezer assembly (100) according to any one of the claims 7 to 11, wherein the device for lifting and lowering is an actuator arrangement.

13. Plate freezer assembly (100) according to any of the preceding claims, wherein the freezing plates (112) are adapted to be parallelly displaced by increasing or decreasing the mutually distance between the freezing plates (112) in order to ease loosing of frozen blocks and/or to increase or decrease the volume of the compartments (111).

14. A method for freezing of a substance by means of a plate freezer assembly (100) according to one of the claims 1-13;

wherein the method comprises the following steps;

- filling each compartment (111) of the freezer plate unit (110) when it is in its filling position with the substance to be frozen from an intake or opening side (113) on top of the compartments (111);

- circulating a freezer agent through the freezing plates (112) of the freezer plate unit (110);

- establishing blocks of frozen substances;

- rotating the freezer plate unit (110) to the emptying position upon completed filling and appropriate degree of freezing;

circulating a hot medium through the freezing plates (112) for a short time and moving the freezing plates (112) apart in a sideways direction, allowing the frozen blocks to move downwards, out of the compartments (111) for transport to a further handling and/or processing station, e.g. to a packing station.

15. Method according to claim 14, wherein a back-to-back configuration of two freezer plate units (110) of the plate freezer assembly (100) now being oriented with the further freezer plate unit (110), with upwards open compartments (111), being in its filling position are filled with the substances to be frozen while the first freezer plate unit (110) below being emptied; and then rotate the two freezer plate units (110), so that the first freezer plate unit (110) is returned back to its filling position, ready for filling while the freezing and emptying of the second freezer plate unit (110) is initiated.

16. Method according to claim 14 or 15, wherein the compartments (111) filled with substances to be frozen are maintained in the filling position until the substances to be frozen are sufficiently frozen to remain in the compartments (111) and then rotating the compartments (111) to the emptying position, whereupon the freezing process is continued till frozen blocks are obtained.