Synthetic gypsum fertilizer product and method of making

Abstract

Embodiments of the invention are directed to pelletized synthetic gypsum and methods and systems for producing pelletized synthetic gypsum. Synthetic gypsum is combined with a binder composition and pelletized to a desired size. The binder composition may include lignosulfonate. Additives may be included in the pellets such as various plant nutrients and micro-nutrients. An additive may include elemental sulfur. The resulting pellets may have a mean pellet size guide number (SGN) from approximately 150 to approximately 300 and a crush strength from approximately 2 lbf to approximately 12 lbf

What is claimed is: 
     
         1 . A method of producing a fertilizer comprising:
 feeding synthetic gypsum to a mixing device;   feeding a binder composition to the mixing device;   mixing the synthetic gypsum and binder composition to form a mixture;   feeding the mixture to a forming device, wherein the forming device comprises an extruder; and   forming the mixture into pellets having a mean pellet size guide number (SGN) from approximately 150 to approximately 300, wherein the resulting pelletized synthetic pellets have a crush strength from approximately 2 lbf to approximately 12 lbf.   
     
     
         2 . The method of  claim 1 , wherein the synthetic gypsum fed to the forming device has a mean particle size of less than 100 microns. 
     
     
         3 . The method of  claim 1 , wherein the binder composition comprises a water soluble binder. 
     
     
         4 . The method of  claim 1 , wherein the binder composition comprises a lignosulfonate. 
     
     
         5 . The method of  claim 4 , wherein lignosulfonate comprises 18% to 48% solids. 
     
     
         6 . The method of  claim 1 , wherein the binder composition comprises starch or a starch derivative. 
     
     
         7 . The method of  claim 1 , wherein the binder composition is selected from the group consisting of brewers condensed solubles, sodium carbonate lignin, cane molasses, beet syrup, beet molasses, desugared beet molasses, whey, soy solubles with cane molasses, hydrolyzed collagen, amino acid solutions, cellulose derivatives, and cellulose based polymer binders. 
     
     
         8 . The method of  claim 1 , further comprising feeding an additive to the forming device, wherein the additive is selected from the group consisting of ground calcium carbonate, calcium bentonite, kaolin clays, manganese, zinc, boron, calcium, copper, and elemental sulfur. 
     
     
         9 . The method of  claim 8 , wherein the additive comprises elemental sulfur. 
     
     
         10 . The method of  claim 1 , wherein the mean SGN is from approximately 250 to approximately 280. 
     
     
         11 . The method of  claim 1 , wherein the forming device comprises a pelletizer. 
     
     
         12 . The method of  claim 1 , wherein the forming device comprises a granulator. 
     
     
         13 . A fertilizer made by the method of  claim 1 . 
     
     
         14 . A fertilizer comprising:
 a plurality of extruded pellets, the plurality of extruded pellets comprising synthetic gypsum and a binder composition, wherein the synthetic gypsum and the binder composition are mixed prior to extrusion, the pellets further comprising mean pellet SGN from approximately 150 to approximately 300, wherein pellets have a crush strength from approximately 2 to approximately 12 lbf.   
     
     
         15 . The fertilizer of  claim 14 , wherein the binder composition comprises a water soluble binder. 
     
     
         16 . The fertilizer of  claim 14 , wherein the binder composition comprises a lignosulfonate. 
     
     
         17 . The fertilizer of  claim 16 , wherein the lignosulfonate comprises 18% to 48% solids. 
     
     
         18 . The fertilizer of  claim 14 , wherein the binder composition is selected from the group consisting of brewers condensed solubles, sodium carbonate lignin, cane molasses, beet syrup, beet molasses, desugared beet molasses, whey, starch, starch derivatives, soy solubles with cane molasses, hydrolyzed collagen, amino acid solutions, cellulose derivatives, and cellulose based polymer binders. 
     
     
         19 . The fertilizer of  claim 14 , wherein the extruded pellets further comprise an additive, wherein the additive is selected from the group consisting of ground calcium carbonate, calcium bentonite, kaolin clays, manganese, zinc, boron, calcium, copper, and elemental sulfur. 
     
     
         20 . The fertilizer of  claim 14 , wherein the extruded pellets further comprise an additive comprising elemental sulfur. 
     
     
         21 . The fertilizer of  claim 14 , wherein the mean SGN is from approximately 250 to approximately 280. 
     
     
         22 . A method of producing a fertilizer comprising:
 feeding synthetic gypsum to a mixing device;   feeding a binder composition to the mixing device, wherein the binder composition comprises starch or a starch derivative;   mixing the synthetic gypsum and binder composition to form a mixture;   feeding the mixture to a forming device, wherein the forming device comprises an extruder; and   forming the mixture into pellets having a mean pellet size guide number (SGN) from approximately 150 to approximately 300, wherein the resulting pelletized synthetic pellets have a crush strength from approximately 2 lbf to approximately 12 lbf.   
     
     
         23 . The method of  claim 22 , wherein the synthetic gypsum fed to the forming device has a mean particle size of less than 100 microns. 
     
     
         24 . The method of  claim 22 , wherein the binder composition comprises a water soluble binder. 
     
     
         25 . The method of  claim 22 , wherein the binder composition comprises a lignosulfonate. 
     
     
         26 . The method of  claim 25 , wherein lignosulfonate comprises 18% to 48% solids. 
     
     
         27 . The method of  claim 22 , wherein the binder composition is selected from the group consisting of brewers condensed solubles, sodium carbonate lignin, cane molasses, beet syrup, beet molasses, desugared beet molasses, whey, soy solubles with cane molasses, hydrolyzed collagen, amino acid solutions, cellulose derivatives, and cellulose based polymer binders. 
     
     
         28 . The method of  claim 22 , further comprising feeding an additive to the forming device, wherein the additive is selected from the group consisting of ground calcium carbonate, calcium bentonite, kaolin clays, manganese, zinc, boron, calcium, copper, and elemental sulfur. 
     
     
         29 . The method of  claim 28 , wherein the additive comprises elemental sulfur. 
     
     
         30 . The method of  claim 22 , wherein the mean SGN is from approximately 250 to approximately 280. 
     
     
         31 . The method of  claim 22 , wherein the forming device comprises a pelletizer or a granulator. 
     
     
         32 . A fertilizer made by the method of  claim 22 . 
     
     
         33 . An extruded fertilizer product prepared by a process comprising the steps of:
 feeding synthetic gypsum to a mixing device;   feeding a binder composition to the mixing device;   mixing the synthetic gypsum and binder composition to form a mixture;   feeding the mixture to a forming device, wherein the forming device comprises an extruder; and   forming the mixture into pellets having a mean pellet size guide number (SGN) from approximately 150 to approximately 300, wherein the resulting pelletized synthetic pellets have a crush strength from approximately 2 lbf to approximately 12 lbf.   
     
     
         34 . An extruded fertilizer product prepared by a process comprising the steps of:
 feeding synthetic gypsum to a mixing device;   feeding a binder composition to the mixing device, wherein the binder composition comprises starch or a starch derivative;   mixing the synthetic gypsum and binder composition to form a mixture;   feeding the mixture to a forming device, wherein the forming device comprises an extruder; and   forming the mixture into pellets having a mean pellet size guide number (SGN) from approximately 150 to approximately 300, wherein the resulting pelletized synthetic pellets have a crush strength from approximately 2 lbf to approximately 12 lbf.