CZ302089B6 - Process for producing meat and bone meal-based fertilizer and fertilizer produced in such a manner - Google Patents

Abstract

In the present invention, there is disclosed a process for producing meat and bone meal-based fertilizer, said preparation process being characterized in that 10 to 35 percent by weight of phosphoric acid is injected into 50 to 70 percent by weigh of meat and bone meal and subsequently a magnesium compound in an amount of 4 to 25 percent by weight is mixed in the mixture obtained in the previous step. Due to the reaction of the meat and bone meal with phosphoric acid and formation of a solidifying binding system due to the reaction thereof with the magnesium compound increase in nutrients amount and adjustment of the meat and bone meal structure for application thereof as a dust-free, structured, organomineral fertilizer and restriction of starting material characteristic bad smell is enabled. There is further described an organomineral phosphorus-nitrogen fertilizer containing a mixture meat and bone meal, phosphoric acid and magnesium compound, consisting of 20 to 32 percent by weight of phosphoric oxide, 3 to 8 percent by weight of total nitrogen and 4 to 15 percent by weight of magnesium oxide.

Description

Process for producing meat-bone meal fertilizer and fertilizer produced by this process

Technical field

The invention relates to organic-mineral fertilizers using secondary raw materials.

BACKGROUND OF THE INVENTION

Meat-and-bone meal is an organic raw material that is produced by grinding and heat-processing of confiscates of animal origin in rendering plants. After destruction of the mass at high temperature and separation of fats, the remaining protein concentrate is dried to a powder. The legal framework of this processing is set out in the Czech Republic in the Decree of the Ministry of Agriculture No. 295/2003 Coll., On confiscations of animal origin, their disposal and further processing. The use of meat-and-bone meal for fertilization is known, but has been limited for preventive reasons following the spread of bovine diseases by transmissible spongiform encephalopathies (BSe). Within the European Union, the use of certain types of meat and bone meal (categories II and ΙΠ under Regulation (EC) No 1774/2002 of the European Parliament and of the Council of 3 October 2002) for fertilization is possible on the basis of Commission Regulation (EC) No 181/2006 of 1 February 2006.

However, the meat-and-bone meal itself is a low-nutrient fertilizer, only about 4 to 10 wt. % nitrogen and 6 to 10 wt. phosphorus as P ₂ O ₅ , so its economy of use is lower than that of conventional mineral fertilizers. Another drawback of the meat-and-bone meal is its powder structure, which is not optimal for fertilizer application both in terms of uniformity of application and environmental impact, since the powdered form of fertilizer annoys its dustiness, is carried by wind outside the target plot and easily flushed into streams. The direct use of meat-and-bone meal is also related to the third problem circuit, which is an unpleasant odor and limited shelf-life of meat-and-bone meal, since as a biological material it is easily subject to micro-organisms and putrefaction processes.

The object of the invention is to increase the nutrient content of the fertilizer, to modify its structure to a dust-free form, to reduce odor and to prolong its useful life.

Methods for preparing granular fertilizers by melting some of the components (CZ 294922 or CZ PV 2000-4733) are described. CZ PV 1993-1114 employs granulation by spraying dissolved fertilizer in the form of mandrel onto previously produced granule seeds and drying them in the fluidized bed. Both of these processes are energy-intensive because they require a considerable amount of heat to melt or dry the material. Other processes use chemical reactions to form a solid structure. These are, for example, condensation ureas with formaldehyde (CZ PV 2000893). EP 0 832 053 uses an ethylene copolymer to form an encapsulated granular fertilizer. Chinese patent CZ 1293172 uses pressure sterilization, enzymatic degradation and fermentation to process meat and bone meal. Canadian patent CA 2011148 proposes to create an organic fertilizer by mixing meat-and-bone meal with organic products such as alfalfa. Similarly, Japanese Patent JP 2225388 proposes the use of meat-and-bone meal in organic starter fertilizers that coat the seeds. However, such a method of using meat-and-bone meal is specific and has no universal use.

Our development work has resulted in a proposal for the use of meat-and-bone meal in an organomineral fertilizer composition and a method for its production, which eliminates the disadvantages of the known solutions, ie. increased energy consumption and use of components not directly involved in the fertilization process. The invention relates to a combination of a product and a method for its production.

- 1 GB 302089 B6

SUMMARY OF THE INVENTION

It is an object of the present invention to modify the utility and application properties of the secondary organic raw material 5 of meat and bone meal, i. increasing the nutrient content, significantly limited its characteristic odor, prolonging the shelf life and adjusting the structure of the finished organomineral fertilizer to allow its dust-free application. This is accomplished by exothermic reaction of the meat-and-bone meal with phosphoric acid, followed by the formation of a solidifying binder system by reaction with the magnesium feedstock, optionally by enriching with other active ingredients and pelletizing the reaction mixture in a perforated die ring press into uniform size pellets.

The meat-and-bone meal contains phosphorus predominantly in the form of hydroxy-1 apatite (calcium hydroxyphosphate - Ca ₅ (PO ₄ fiOH)), which is a water-insoluble substance and therefore the availability of this phosphorus to plants is limited. with phosphoric acid (H3PO4), which converts normal calcium phosphate into more soluble and therefore more accessible forms of phosphorus - dicalcium phosphate (CaHPO ₄ ), possibly even monocalcium phosphate (Ca (H ₂ PO ₄ ) _2. ) This reaction is slightly exothermic. The actual chemical reactions serve here as phosphoric acid as a source of phosphorus, ie it increases its insufficient content in the original raw material.

By mixing the liquid, the reaction mixture is freed from undesirable dust particles which, because of their large specific surface area, react preferentially and form a viscous film on the surface of larger particles. This film increases the adhesion of the particles to each other and agglomerates them into larger granules, which is a desirable form for future use of the product.

The agglomerate surface layer, which contains a solution of said calcium phosphates, has an acidic reaction, which is utilized in the second reaction step. Soluble calcium phosphates and the remaining phosphoric acid are reacted with the magnesium compound. Magnesium oxide is preferably used for this purpose, since the neutralization reaction therein has a significant exothermic coloration which is used in the process to evaporate excess water. This creates a supersaturated binder film of mixed magnesium phosphates which binds the reaction mixture particles to larger agglomerates. When the fertilizer cools, the dissolved phosphates pass onto the kiy stoves with wires that export the remaining water, resulting in solid fertilizer granules that impart dust-free properties to it.

This basic process can be modified by increasing the nutrient content by adding additional phosphate fertilizers (eg mixed ammonium phosphate -NH ₄ H ₂ PO ₄ + (NH ₄ ) ₂ HPO ₄ , called Amophos, or superphosphate, essentially calcium dihydrogen phosphate - Ca (H ₂ PO ₄ ) 2). The water-soluble component of these fertilizers behaves in the same way as phosphoric acid in the second stage of the process and contributes to the formation of a solidifying binder system.

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The second effective process to achieve the result has been an integrated process in which the meat-and-bone meal has been premixed with the magnesium compound, and the mixture is then reacted together with phosphoric acid. In this case, the simultaneous decomposition of the insoluble calcium phosphates in the meat-and-bone meal and the reaction of phosphoric acid and soluble phosphonates with magnesium ions to form mixed magnesium phosphates, which form the basis of the solidifying binder system of the fertilizer. The advantage of this procedure is to reduce the sensitivity of the composition to the introduced dose of fluid without forming an undesirable pasty structure of the composition. This allows a higher dose of phosphoric acid to be introduced and a smooth processing of the formulas with higher phosphorus fertilizer enrichment. In this case, a small proportion of the meat-and-bone meal remains undecomposed and causes a slower release of nutrients in the soil. This is environmentally beneficial because slow-acting fertilizers show less nutrient loss by leaching out of the soil and therefore have less negative impact on surface waters.

In addition to the spontaneous formation of granules of unspecified shape during the mixing process, the reaction mixture may be formed into pellets of the desired shape by means of a suitable pelletizing press. This is

It is advantageous to carry out the reaction immediately after the reaction as long as the reaction mixture is compliant. This is preferably done immediately after the reaction as long as the reaction mixture is compliant. Certain types of presses also allow processing of the solidified reaction mixture.

An important finding is that the reaction mixture, after passing through the described process, has a significantly altered and limited odor, approximately similar to conventional dog food.

DETAILED DESCRIPTION OF THE INVENTION

The following examples illustrate the process of the invention.

Example I

156 kg (ie 52% of the total weight of the raw materials) of the meat-and-bone meal containing 8.9 wt. total P ₂ O ₅ . 105 kg (i.e. 35% of the total weight of the raw materials) of 58.5 wt% phosphoric acid were injected into this amount. P2O5. The reaction mixture was heated to 60 ° C as a result of the exothermic reaction and the initially powder mass obtained a wet granulate structure. 39 kg (13% of the total weight of the raw materials) of the powdered magnesium oxide was slowly introduced into this preform, further increasing the temperature of the mixture to about 95 ° C and strengthening the agglomerates. 298 kg (i.e. 99.3% of the total weight of the raw materials; 0.7% of the total weight of the raw materials are lost by evaporation) of the granulated fertilizer containing 25.3 wt. % P ₂ O ₅ 4.2 wt. % of total N and 9.7 wt. MgO. The original characteristic odor of the raw material was significantly reduced after the heat treatment.

Example 2

155 kg (i.e. 51% of the total weight of the raw materials) of the meat-and-bone meal containing 8.9 wt. P ₂ O ₅ , 105 kg (ie 34.5% of total weight of raw materials) Amofos fertilizers (mixture of primary and secondary ammonium phosphate, approx. 70% NH ₄ H ₂ PO ₄ and 30% (NH ₄ ) ₂ HPO ₄ containing 52 , 1% by weight of P ₂ O ₅ and 12 kg (ie 4% of the total weight of the raw materials) of magnesium oxide 32 kg (ie 10.5% of the total weight of the raw materials) were injected with 55.8% phosphoric acid wt.% P ₂ O _5. the temperature of the mixture in the exotherm rose to 78 ° C and was kaglomeraci particles. yield: 301.5 kg (i.e. 99.2% of the total weight of raw materials; 0.8% by weight of the total amounts of raw materials evaporation) of a dust-free semi-granulate fertilizer with a content of 28.6% by weight of P ₂ O _{5. The} characteristic odor of the raw material was modified to the level of conventional pet foods pellets by the production process described.

Industrial applicability

The process according to the invention is industrially applicable in chemical industry companies engaged in the production or mixing of fertilizers. Its feasibility has been verified on an operational scale as shown in the examples. The advantages of the product produced by the process according to the invention are particularly advantageous for fertilizer users; in agricultural practice. It is a reduction in the cost of fertilizer application, because its increased concentration compared to raw meat and bone meal reduce the number of travels in the field, as well as dust removal, and thus improve the culture of working with fertilizer during its transportation, storage and application itself. This advantage of the new solution will also have a positive impact on the environment, as the fertilizer is distributed more evenly on the treated land without affecting its surroundings. In addition to its chemical function in the binder system, magnesium is a valuable nutrient. It is also an advantage of the invention to significantly reduce the unpleasant odor that is characteristic of the raw material.

Claims (6)

PATENT CLAIMS Process for producing an organic mineral fertilizer based on meat-and-bone meal, characterized in that the meat-and-bone meal comprises 50 to 70% of the total weight of the raw materials, wherein the meat-and-bone meal comprises 6 to 10% by weight. % of total P105, injects phosphoric acid at a dose of 10 to 35% of the total weight of the raw materials, the phosphoric acid containing 50 to 60% by weight of the total feedstock. P2O5, and a magnesium compound, preferably magnesium oxide, is added to the mixture in a batch 10 4 to 25% of the total weight of the raw materials. Process for producing an organic mineral fertilizer based on meat-and-bone meal, characterized in that the meat-and-bone meal is in a dose of 50 to 70% of the total weight of the raw materials, wherein the meat-and-bone meal contains 6 to 10% by weight. total P2O5, first mixed with magnesium 15 to 15% by weight of the compound, preferably magnesium oxide, at a dose of 4 to 25% by weight of the total feedstock, and phosphoric acid is injected into the mixture at a dose of 10 to 35% by weight of the feedstock. P2O5. Production method according to claims 1 and 2, characterized in that the meat-and-bone meal is pre-treated By further processing as described in claims 1 and 2, it is mixed with a phosphate feedstock containing a water-soluble P2O5 other than phosphoric acid, preferably at a dose of 10 to 35% of the total weight of the feedstocks. Production method according to claims 1 and 2, characterized in that the produced mixture is pre-treated 25 solidifies into uniform particles by pelletizing. 5. An organic mineral phosphate-nitrogen fertilizer, characterized in that the fertilizer is a mixture of meat-and-bone meal, phosphoric acid and a magnesium compound, preferably magnesium oxide, containing a total of 20 to 32 wt. % P2O5, 3 to 8 wt. total nitrogen and 4 to 15% 30 wt. MgO. Fertilizer according to claim 5, characterized in that the fertilizer is a mixture of meat-and-bone meal, phosphoric acid, a phosphate feedstock containing a water-soluble P2O5 other than phosphoric acid, and a magnesium compound, preferably magnesium oxide, containing 20 to 32 wt. % P2O5, 3 to 8 wt. % nitrogen and 4 to 15 wt. MgO.