Abstract:
A seed treater provides enhanced seed coating capabilities and performance. The seed and/or treatment fluid may be heated for improving vaporization and absorption by the seed. Air may be injected in the seed treater to provide heat, dehumidified air, and to provide vaporization enhancement, and component cleaning functions. The functions may be controlled by a control processor based on recipes and may be changed dependent upon sensed or input environmental conditions such as temperature and humidity.

Description:
[0001]    This application claims the benefit of U.S. Provisional Patent Application No. 61/624,668, filed Apr. 16, 2012, entitled SEED TREATER WITH IMPROVED FLUID APPLICATION MEANS, said application being hereby fully incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention generally relates to an apparatus for surface treatment of seeds. More particularly, the present invention relates to a device for surface treatment of seeds having an improved fluid application means. 
       BACKGROUND OF THE INVENTION 
       [0003]    Seeds that are planted for agricultural and other purposes are often treated prior to planting. The treatments may accomplish many different purposes including deterrence or prevention of insect and other anima pests that would target sown or newly germinated seed for attack. These animals may directly cause damage to the seed or may introduce one or more pathogens, including viruses, directly into the seed. Treatments may also target bacteria, molds and fungus that have contaminated seeds or that are known to be present in the soil in which the seeds will be planted. Direct application of seed treatment allows for a reduction in the amount of treatment composition that would be required by application to soil after planting. Also, post-planting application may not penetrate the soil to a level or location where it would be effective. Treatment of seeds, however, involves applications of chemicals and other agents that are expensive and may even be toxic to the seeds on which they are applied. The amount of treatment composition is also necessarily small and often provides protection or other advantage for only a short period of time after planting. However, in a number of situations, the advantages of treatment with one or more compositions will outweigh the disadvantages. These situations include the use of rare or expensive seed, the use of older seed or seed with low germination rates, the use of seed known to be contaminated or infested, the use of seed known to have been produced in conditions likely to lead to contamination or infestation, and the use of seed in fields known to be prone to contamination or infestation. 
         [0004]    Various devices for treatment of seeds in batch or continuous treatment mode are known. U.S. Pat. No. 5,891,246 to Lund, the disclosure of which is hereby incorporated by reference, describes a seed coating apparatus for applying a coating fluid whereby seeds are dispersed with a seed dispersing member. 
         [0005]    U.S. Pat. No. 4,657,773 to Mueller, the disclosure of which is hereby incorporated by reference, describes a process and apparatus for dressing seed in which seed is guided over a dispensing cone through a jet of dressing and onto a rotary table. 
         [0006]    DE 4411058 to Niklas, the disclosure of which is hereby incorporated by reference, describes a device with a mixing bowl connected to a high speed, multi-turn actuator and a mechanism to feed seed into the mixing bowl. The bowl rotates to rotate seed being treated therein. The seed treating formulation is sprayed in the bowl while the seed is being rotated to uniformly coat the seed with the formulation. 
       SUMMARY OF THE INVENTION 
       [0007]    The apparatus of the invention is directed toward an apparatus for surface treatment of seeds. Treatment apparatus according to the invention can treat seeds continuously or in batches. Treatment fluid is delivered into a treatment area of system by a fluid communication line and distributed onto seeds such as via rotation of an atomizer wheel configured as a centrifugal apertured plate. Means are provided to increase the absorption and/or adhesion and/or drying time of the treatment fluid with seed being treated. In embodiments of the invention, means are provided to enhance the vaporization of the treatment fluid. In embodiments heat is added to the treatment region of the seed. In certain embodiments, conditioned air may be heated and/or dehumidified and provided into the seed treatment apparatus at, for example, the fluid application region. The conditioned air may be provided to the seed or seed stream prior to fluid application region. In embodiments, conditioned air includes dehumidified air to enhance the vaporization of the treatment fluid. In an embodiment the treatment fluid temperature is altered. 
         [0008]    In embodiments of the invention, heated air is directed at the centrifugal plate with an air delivery duct. In such embodiments, the air delivery tube delivering the heated air may surround the fluid flow line delivering the treatment fluid to the fluid application region. The heated air flow also warms the fluid in the fluid flow line. In certain embodiments, the fluid may be more directly heated with a dedicated heat source, such as electric heating elements, applied directly to a treatment fluid reservoir or to a fluid line in or going to the seed treater. Heating of the fluid may occur prior to the commencement of the seed treatment and/or during the seed treatment. In certain embodiments, the fluid may be heated to a particular temperature for treatment before dispersion. In certain embodiments, the fluid may be heated from ambient to a particular temperature or temperature differential prior to application to the seeds. In certain embodiments, particular components of seed treater may be heated, that is, for example, a treatment bowl or centrifugal plate. This may provide reduced viscosity of fluid in contact with the component as well as lowering the vapor pressure of the fluid, in embodiments, the seed is warmed prior to or during application of the fluid. In certain embodiments, the air may be injected within the seed stream flow ahead of the region where the seeds are treated effectively warming the seeds before treatment. In other embodiments, the seeds may be preheated by other means, such as heating the seed containment. 
         [0009]    In embodiments of the invention, such heating and/or air conditioning as described above, may be automatically controlled and may be part of treatment recipes provided to a process controller controlling the equipment. In embodiments, the heating and/or air conditioning as described above, may be automatically controlled based upon existing environmental conditions. For example, if an ambient temperature is below 50 degrees Fahrenheit, the seed stream may be warmed, and/or the treatment fluid may be warmed to a desired temperature suitable for optimal seed treatment. 
         [0010]    A feature and advantage of embodiment of the invention is optimally controlling the evaporative properties within a seed treater to maximize seed treatment efficacy and minimize treatment time. 
         [0011]    A feature and advantage of embodiments of the invention is enhanced seed coating, in particular, more uniform thorough coating in less time. Additionally, a feature and advantage of embodiments of the invention is less dust generation. 
         [0012]    A feature and advantage of particular embodiments of the present invention where air is injected into the top side of the mixing bowl is improved dispersion of treatment fluid. Air is blasted from the air delivery tube into the centrifugal plate as the plate is spinning providing enhanced dispersion of the treatment fluid. The combination of the blowing air with the spinning plate functions to increase the atomization of the fluid particles, which provides better fluid dispersal from the atomizer. Providing heated and/or dehumidified air can further enhance the vaporization of the treatment fluid. 
         [0013]    Another feature and advantage of embodiments of the present invention is enhanced treatment fluid absorption on the seeds. By heating the fluid, for example inline with the air delivery tube surrounding the fluid communication line and at the centrifugal plate, the viscosity and vapor pressure of the fluid is lowered. As such, when the fluid is dispersed from the atomizer and contacts the seeds, the fluid is more readily absorbed and retained on the surface of the seeds. 
         [0014]    Another feature of embodiments of the invention is the injection of the conditioned air circumferentially inside a containment housing for a mixing bowl. In embodiments the air is injected in a radial direction at the top of the bawl containment. In an embodiment the air outlet port is radially outward and downward, in an embodiment the air is directed circumferentially to correspond with the rotation of the seed in the rotating bowl. 
         [0015]    A further feature and advantage of embodiments of the present invention is a cleaner fluid treatment bowl and centrifugal plate. Due to the enhanced dispersion of the warmed fluid, the increased absorption of the fluid by the seeds, and the air-scrubbing of the components, such as the spinning centrifugal plate, a greater percentage of fluid remains with the seeds. There is therefore less buildup of leftover fluid within the treatment area, resulting in cleaner post-treatment equipment. 
         [0016]    Another feature and advantage of embodiments of the present invention is a reduced amount of time to treat a batch of seeds. Increased dispersal of treatment fluid and absorption of fluid by the seeds means that the seeds need to spend less time being treated to obtain the same or better level of treatment. As such, each batch can be processed more quickly, which leads to increased seed capacity for the particular apparatus and the plant utilized the apparatus as well as the ability to apply addition seed treatments. 
         [0017]    Another feature and advantage of embodiments of the present invention is reduced treated seed dust levels. Application of heated or unheated air during treatment fluid application allows for increased application rates of polymer based or other dust control seed coating products to provide for better seed treatment adhesion to the seed and or improved durability of the seed treatment to reduce attrition of the treatment during post treatment handling and planting. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    The embodiments of the present invention may be more completely understood in consideration of the following detailed description of various embodiments of the invention in connection with the accompanying drawings, in which: 
           [0019]      FIG. 1A  is schematic view of a continuous feed seed treatment system according to an embodiment of the present invention. 
           [0020]      FIG. 1B  is perspective view of a batch seed treatment system according to an embodiment of the present invention. 
           [0021]      FIG. 2  is an image of a portion of a seed treatment system according to an embodiment of the present invention. 
           [0022]      FIG. 3A  is a perspective view of a bowl, dispense portion, and air inlet port of a seed treatment apparatus of a batch treating system according to an embodiment of the present invention. 
           [0023]      FIG. 3B  is a cross section view of a bowl, dispense portion, and air inlet port as illustrated in  FIG. 3A  of a seed treatment apparatus according to an embodiment of the present invention. 
           [0024]      FIG. 3C  is a perspective view of a bowl, dispense portion, and air inlet port of a seed treatment apparatus according to an embodiment of the present invention. 
           [0025]      FIG. 4  is a drawing of a liquid dispersion portion of a seed treatment system according to an embodiment of the present invention. 
           [0026]      FIG. 4  B is a plan view of the dispense portion of a seed treatment system according to an embodiment of the present invention. 
           [0027]      FIG. 5  is plan view of a seed treatment system including an air conditioner according to an embodiment of the present invention. 
           [0028]      FIG. 6  is a perspective view of a portion of a control processor with an interface and heater unit of a seed treatment apparatus according to an embodiment of the present invention. 
           [0029]      FIG. 7  is a side view of a portion of a continuous feed seed treatment system according to an embodiment of the present invention illustrating the seed stream. 
       
    
    
       [0030]    While the present invention is amendable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the present invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present invention. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0031]      FIG. 1   a  shows a schematic figure of a system in accord with the invention. A seed treater  1  has a seed treatment region  2  and with a stock  3  of seeds to be treated, a fluid dispense station  4  providing treatment fluid to the seed treater. Conditioned air may be provided to the seed treater by air conditioning units  5  that may heat and/or dehumidify air. Alternate locations of providing the heated air are illustrated. Such conditioned air can also be provided to the seed treater either at the containment region or as the seed is being conveyed to the seed treater. Heat  6 , indicated by the wavy lines, may be provided to the treatment fluid at the dispense station  4 , at fluid lines  7  connected to the seed treater, directly to components of the seed treater, such as an internal fluid line. The heat may be provided by electric heating elements  19 . 1 , such as radiant heat or by elements conductively connected to components, for example, electric heating coils. Also the heat  6  may be provided by heated air. 
         [0032]    A control processor  8  with operator interface  8 . 1  can be connected to control all functions of the components and can store and or receive recipes. See co-owned applications Nos. WO 2012/078928 and WO 2012/078918 that are hereby incorporated by reference herein. The control processor and other equipment can be connected to the internet and remote locations with the functionalities and capabilities as described in these two co-owned application. The control processor  8  can be connected to sensors  9  that can sense environmental conditions, such as temperature and humidity, and change the operating characteristics/parameters in accord with preprogrammed or input instructions. For example, when the temperature drops below a certain level, heat or heated air can be provided to the seed treater, and/or treatment fluid, and/or seed. Or, if the humidity is excessive, dehumidified air can be provided. 
         [0033]      FIG. 1   b  shows a seed treater apparatus  10  according to an embodiment of the present invention that can include an untreated seed hopper  12 , scale  14 , control panel  22 , and conveyance hopper  16 . Treatment containment housing container  18  along with discharge hopper  20 , premix containers  24 ,  46 , metering pump motor controllers  30 ,  32 , pumps  38 , and bowl motor  81  are mounted to a lower frame component  42 . 
         [0034]    Seed for treatment may be introduced into untreated seed hopper  12  which is mounted at the top of upper frame component  44 . Seed contained therein may be dispensed to a scale  14  for weighing and identification of a batch for treatment. Scale  14  may be a manual scale and fed by means of a magnetic or vibratory feeder from untreated seed hopper  12  to scale  14 . In the alternative, a load cell may be employed to identify and dispense a batch for treatment. Feed is controlled by control processor  22  to operate until such time as scale  14  indicates to controller  22  that the desired weight has been reached. At this point, feeder is stopped and the batch dispensed to conveyance hopper  16 . Conveyance hopper  16  operates to collect the batch identified for treatment and directs the batch to treatment container  18 . 
         [0035]    Treatment agents for use in the modular seed treatment apparatus of the invention may be prepared in one or more pre-mix containers, which can be reversibly mounted to the frame assembly. The pre-mix containers  24 ,  46  may each hold up to ten gallons of solution. Fluid treatment reservoirs  19 , configured as pre-mix containers  24 ,  46  may have agitation devices associated with them including a motor  26 ,  28  deploying a rod with two or more paddles for agitation of liquid contained therein and may also have heaters  19 . 2 . Referring to  FIG. 1A , fluid treatment reservoirs  19  configured as drums may have heating units  19 . 1  and sensors associated therewith to heat the liquid. Additionally heaters  19 . 2  may be applied to the liquid input line  7 . 
         [0036]    Containment housing  18 , as seen in  FIGS. 1A ,  1 B,  2 , and  3 B includes a body portion  68  and a lid  84 . Lid  84  can be secured to body  68  by a mechanical connection including, but not limited to, bolts extending through lid and into a flange on body or clamps. An atomizer comprising a centrifugal plate  80 , as shown in  FIGS. 3 and 4 , is disposed within the interior  93  of treatment container and revolves at high speed to disperse treatment composition. Liquid dispersion portion  80  configured as a centrifugal tray or plate with a cylindrical or frustoconical shaped portion  80 . 2  extending upwardly is driven by atomizer motor  50 . Treatment container  18  can also include fins extending from lid  84  designed to direct seeds entering treatment container  18  and within treatment container toward centrifugal plate  80  and/or bowl  66 . Bowl  66  is a seed dispersion portion of the apparatus and is disposed within treatment container  18  and is driven by a bowl motor  81  to rotate in a horizontal plane. Bowl motor is set to operate at speeds sufficient to impart centrifugal force to seeds being treated to drive the seeds toward the wall and upward toward fins and an outlet port  87 . Bowl motor is controlled by control processor  8 . Seed outlet port may include openable and closeable gate  87 . 1  which may be manually operated or electrically operated and may be automatic and controlled by control processor  8 . Cover or lid  84  also defines one or more openings for traverse of one or more fluid communication lines  92 , sensor lines  93 . 1  for temperature sensors  93 . 2 , and dust discharge ports  93 . 4 , and/or conditioned air outlet ports, and seed input ports  93 . 5 . Seed treatment liquid input line  92  discharges the treatment fluid  93 . 3  into the liquid dispensing portion or tray  80 . Seed  96  enters the interior  93  through the port  93 . 5  and by way of the seed dispersion portion, the rotating bowl  66 , which elevates the seed into an annular seed treatment region  96 . 2  where the spray  96 . 4  from the liquid dispersion portion  80  contacts the seed. Exterior blowers  98 . 4  with motors  98 . 5  may be used to remove dust and assist in the exit of the conditioned heated air. 
         [0037]    The figures illustrate an air inlet port  101  an air delivery conduit or duct  102  that extends from an air conditioner  97 . 8  to the open interior  93  of the containment housing  18  for injecting conditioned air into the system. In one embodiment, as can be seen in  FIGS. 3A ,  3 B,  4 , and  4 B, the air delivery duct  102  surrounds the seed treatment liquid input line  92 . Air can be delivered through air delivery tube  102  simultaneously as treatment composition is delivered through fluid communication line. 
         [0038]    In one embodiment, air is provided by a blower. In another embodiment, the air is provided through a compressed air line with a diffuser. In an embodiment shown in  FIGS. 4 and 5 , air conditioner including a heater portion  95 , the blower  95 . 2  or compressed air source can be controlled by the control panel  22  of the control processor of device. If the air is to be heated and/or dehumidified prior to directing it to the treatment container  18 , the control panel  22  can also contain the heat source. Control panel  22  can include various displays and controls, including, for example, outgoing air temperature, outgoing air relative humidity, incoming air temperature, incoming air relative humidity and seed temperature. 
         [0039]    Air provided through air delivery tube  102  can be heated air or non-heated air and/or dehumidified air. Blasting the centrifugal plate  80  with air during the application of treatment fluid provides for better atomization of the fluid particles due to the combination of the spinning plate and the blowing air. Use of air also provides for a cleaner bowl  66  and plate  80  following treatment. Heating the air prior to dispersal can provide additional advantages. As the heated air travels through the air delivery tube  102  simultaneously as the treatment fluid  93 . 3  travels through the fluid communication line, the heated air elevates the temperature of the fluid in-line. Elevation of the temperature of the fluid causes the viscosity and vapor pressure of the fluid to be lowered, which results in better dispersion of the fluid by the centrifugal plate and better absorption of the fluid by the seeds. In addition, the heated air serves to warm the centrifugal plate  80 , which magnifies the beneficial effects of the heated fluid by further heating the fluid. In one embodiment, heated air is provided at 150 degrees Fahrenheit. In other embodiments, about 140 degrees F. In other embodiments, about 130 degrees F. In an alternative embodiment, rather than, or in addition to, providing the air (heated or non-heated) via an air delivery tube  102  surrounding the fluid communication line  92 , air can be injected circumferentially from around the side of the bowl  66  as illustrated by the air outlet  97  in  FIG. 3B .  FIG. 3C  illustrates another embodiment where the conditioned/heated air  99  is directed out radially by an air deflector  99 . 1 . 
         [0040]    Addition of heated air into system has also been found to reduce the batch time necessary to coat a batch of seeds with treatment fluid and to reduce the amount of dust on treated seeds due to both the effects of the air flow and heat. Reduced application time provides the opportunity for significant advantages, including higher seed plant capacity as well as additional coating to improve dust retention, seed appearance and seed flow. 
         [0041]    In one mode of operation, an operator may place a quantity of seed to be separated into batches and treated in place in untreated seed hopper  12 . Seed is dispensed by operation of vibratory feeder into scale  14 . Pre-mix container  24  is charged with ingredients for the treatment composition and agitator motor  26  is engaged to mix and maintain composition of the treatment composition. A second treatment composition may be prepared by charging a second pre-mix container  46  with ingredients for the second treatment composition and engaging agitator motor  28  to mix and maintain composition of the second treatment composition. When heated air is desired to be introduced into treatment container  18 , a heat source and blower associated with the control panel  22  may be activated. Predetermined quantities of seed are then dispensed by scale  14  to conveyance hopper  16 . Seed falls into treatment container  18  and falls into bowl  66 . Rotation of bowl  66  causes seed to be urged to the outside of the bowl and against the inner side of treatment container  18  as well as upward toward lid  84 . Fins direct seed back toward the center of treatment container  18  and down toward bowl  66 . Controller  22  operates to introduce treatment composition from one or both pre-mix containers  24 , 46  by operation of pumps  38 ,  60  into the treatment space inside treatment container  18  through fluid containment line  92 . Simultaneously, heated or unheated air is introduced into treatment container  18  through air delivery tube  102 . Seed is then allowed to interact with the one or more treatment compositions for a pre-determined period. Optionally, dry powder may be dispensed from powder container  34  into the treatment space from powder conveyer  36  according to the program set in controller  22 . A second pre-determined period is allowed to elapse to allow for coating of treated seed with the introduced powder. Controller  22  then directs opening of seed exit gate or door  873  and treated seed is directed through collection hopper  20  to packaging equipment or other destinations as desired by the operator. Further details of the features and operation of seed treatment apparatus can be found in United States Patent Application Publication No, 2006/0236925, which is hereby incorporated by reference. 
         [0042]      FIGS. 1   a  and  7  depicts another embodiment of the present invention in a continuous feed seed treatment apparatus  200  wherein heat such as through heated air is introduced into a continuous seed processing apparatus  200 . Seed treatment apparatus  200  can include a housing  202  including an seed inlet port  204 , a seed wheel  206 , a dispersion portion configured as a cone  208  that leads to an annular treatment region  209 , an atomizer wheel or centrifugal plate  210 , and an outlet  212 . Housing outlet  212  can connect to a polishing drum  216  or mixing chamber. The atomizer wheel  210  can be fluidly connected to one or more tanks containing products for treating the seeds via an inlet tube that may be heated. The system can be connected to a computer system  8 , a control processor, having a control panel for monitoring and/or adjusting the system. The system  200  can further include an air delivery tube  214  that delivers air to the system in the same general manner as described above. As explained previously, air can be heated or unheated and dehumidified and can be provided by a blower or a compressed air source. In embodiments, the air provided is through a dedicated air inlet, that is separate from the other inlets and separate from the fluid inlet. Further details of continuous seed processing system  200  can be found in United States Patent Application Publication No. 2011/0027479, which is hereby incorporated by reference. 
         [0043]      FIG. 7  illustrates an exemplary seed stream  96 . 9  through a continuous feed seed treater. Seed  96  can first be fed into the apparatus at the housing inlet such that it travels through the apparatus under the influence of gravity. In a preferred configuration, the apparatus is therefore vertically arranged. After entering the housing, the seed travels into and fills metering compartments, such as slots, in the seed wheel. The seed wheel is configured to collect a predetermined quantity of seed as it rotates to ultimately dispense the seed into a seed stream. In one embodiment, the seed wheel meters the seed based on a volume of the seed. Seed wheel  206  can be rotated by a motor, such as, for example, a ⅓ horsepower variable speed motor, to dispense the seed once it has been metered and to rotatably fill each adjacent slot in the wheel. After being dispensed from the seed wheel, seed falls onto the dispersion cone. The dispersion cone dispenses the seeds generally uniformly into a curtain of treatment fluid provided by the spinning atomizer wheel. Air is delivered to the atomizer wheel with the treatment fluid via air delivery tube  214 . Seeds are then ejected out of the housing outlet and can subsequently be further processor or packaged. The embodiments above are intended to be illustrative and not limiting. 
         [0044]    The above references in all sections of this application are herein incorporated by references in their entirety for all purposes. 
         [0045]    All of the features disclosed in this specification (including the references incorporated by reference, including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. 
         [0046]    Each feature disclosed in this specification (including references incorporated by reference, any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features. 
         [0047]    The invention is not restricted to the details of the foregoing embodiment (s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any incorporated by reference references, any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed The above references in all sections of this application are herein incorporated by references in their entirety for all purposes. 
         [0048]    Although specific examples have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement calculated to achieve the same purpose could be substituted for the specific examples shown. This application is intended to cover adaptations or variations of the present subject matter. Therefore, it is intended that the invention be defined by the attached claims and their legal equivalents, as well as the following illustrative aspects. The above described aspects embodiments of the invention are merely descriptive of its principles and are not to be considered limiting. Further modifications of the invention herein disclosed will occur to those skilled in the respective arts and all such modifications are deemed to be within the scope of the invention.