Table of Contents
Organic fertilizers are full of nutrients, but the concentration is low and the fertilizer effect is slow. Chemical fertilizer has high nutrient and quick effect, but long-term application will cause soil compaction and acidification. Organic-inorganic compound fertilizer is a new type of fertilizer made from fermented organic materials such as livestock and poultry manure, plant residues, etc., adding some chemical fertilizers, fully mixing and then granulating.Strengths, it’s both inorganic fertilizer quick fertilizer effect of organic fertilizer soil improvement and lasting fertilizer effect of advantages, complement each other each other to adjust, maintain and improve soil fertility, and improve crop production and agricultural product quality improvement, to achieve high yield and high quality, the purpose of the application of ecological security, to keep the agricultural sustainable development is of great significance.
The effect of organic and inorganic compound fertilizer is remarkable, but the development is slow. The reasons are as follows: first, due to the different resources of organic materials in various regions, the treatment process is complex, and the pretreatment cost is high. In the production process, due to the strong water absorption and looseness of organic materials, it has a great impact on the granulation and drying processes, it is difficult to granulate, it is difficult to dry, and the production cost is relatively high. Unacceptable for a while. Second, although GB18877 has changed its version, the inspection method for organic matter content is similar to the method for measuring carbon in lignite. At present, some compound fertilizer enterprises do not have organic material fermentation devices to produce organic and inorganic compound fertilizers. Most of the organic raw materials are directly used without The ammoniated lignite powder with high organic matter content affects the fertilizer efficiency of organic-inorganic compound fertilizers. Therefore, in order to accelerate the promotion and application of organic and inorganic compound fertilizer, the following three links must be grasped in the actual production:
Pretreatment of organic materials.
Pretreatment process usually refers to organic fertilizer fermentation process. Fermentation decomposition is the basis of organic fertilizer quality. The ideal conditions for fermentation include:
①The moisture. Maintaining proper water content is the primary condition to promote microbial activity and compost fermentation. Generally, the maximum water holding capacity is about 60%. Too much moisture will prolong the heating time, on the contrary, the heating will be fast, but the cooling is also fast, and the decomposition is not complete. Only proper moisture can keep fermentation materials in the range of 50-65℃.
②Ventilation. Keep proper air in the pile, conducive to the reproduction and activity of gas-friendly microorganisms, promote the decomposition of organic matter. When composting at high temperature, we should pay attention to the appropriate accumulation tightness. In trough fermentation, we should add auxiliary materials according to the process requirements as far as possible to facilitate ventilation.
③Maintain a neutral or slightly alkaline environment. Suitable PH environment can promote microbial reproduction and activity. Adjust the PH, when the material is too alkaline, you can add an appropriate amount of H3PO4 (phosphoric acid), KH2PO4 (potassium dihydrogen phosphate), FeCl3, FeSO4·7H2O. If the material is acidic, add CaO (quicklime), NaOH (caustic soda), K2HPO4(dipotassium hydrogen phosphate) one of them can be.
④ C/N ratio. The C/N ratio of microbial decomposition to organic matter is 25∶1. The ratio of carbon to nitrogen was 15-25 ∶1 for legumes, 25-45 ∶1 for weeds, and 60-100 ∶1 for gramineous crops. Therefore, according to the types of compost materials, appropriate amount of substances with high nitrogen content should be added to adjust, so as to reduce the C/N ratio and promote microbial activities.
The organic material fermentation process route is to mix wet manure with straw powder and fermented dry organic material, and reduce the moisture content of the mixed material from 80% to about 55%; if the fresh manure moisture is suitable for the fermentation process requirements, then The process of dry and wet mixing can be omitted; biological fermentation is used to exothermic heating and sterilization to evaporate water, so that the water content is reduced to less than 30%, and the volume is reduced to meet the requirements of harmlessness and resource utilization.
The fermented organic materials do not need to be bagged when they are out of the tank, and are generally piled into the warehouse for 7-15 days of aging treatment.
Granulation and drying adjustment.
The organic-inorganic compound fertilizer can be produced by a typical solid pellet method, and the technological process is basically similar to the chemical compound fertilizer process. The difference is that granulation needs to use drum and disc two stages granulation, drying also needs continuous two drying, in order to make the moisture particle strength and not agglomerate requirements. The production of organic-inorganic compound fertilizer requires the addition of 30% organic materials, and four factors that affect the production of organic materials must be fully considered:
①Moisture problem. Good fermentation bacteria, good fermentation device and reasonable fermentation cycle can reduce the moisture content of the fermented material to 25%, otherwise it needs to be pre-dried or concentrated in sunny days and used in batches. The high water content of the material not only increases the drying load of the production line, but also makes it impossible to produce the formula with high urea content.
The organic-inorganic compound fertilizer needs to be thermally granulated. The granulated material is within a certain liquid phase range, and the viscosity of the material is good. The comprehensive moisture of the new material formula entering the granulator cannot exceed 10%, and the organic raw material moisture is required to be less than 25%. The nutrient content of the raw material should be high and the moisture content should be low.
② fineness problem. The finer the material, it can not only improve the viscosity of the material, but also increase the proportion of the material, both of which are conducive to granulation, so that the particle is round and the surface is bright. There are many coarse impurities in organic material fibers. At present, there is no suitable high-humidity material fine powder machine. Enterprises generally perform pre-drying and then finely pulverize. The proportion of fineness of organic materials used for granulation: 60% or more of 60 mesh, and only 40% of 60-40 mesh.
③ the proportion of the problem. The specific gravity of organic materials before fermentation is generally 0.5, and after fermentation and decomposition, the specific gravity is 0.7. If the specific gravity of the granulated material is light, it cannot complete the required movement track for granulation. Production of organic and inorganic compound fertilizer, generally need to choose high organic matter, high nutrient content of raw materials, leave enough space to adjust the proportion and viscosity of materials.
④ Stickiness problem. The organic and inorganic compound fertilizer formula needs to add about 30% organic materials to ensure the organic matter content reaches the standard. Organic materials are generally not viscous, full fermentation and decomposition, fine crushing, although can improve the viscosity of organic matter, but still can not meet the viscosity requirements required by the aggregate granulation method, so adding a certain amount of viscous granulation binder is essential. However, the national standard of organic and inorganic compound fertilizer has double requirements for nutrients and organic matter, and the space of adding amount is limited, so the added viscosity must be less and good.
The mandatory technical standard of the national organic-inorganic compound fertilizer (GB18877-2009) stipulates that the (N+P2O5+K2O) nutrient is 15-25% and the organic matter content is not less than 20%; (N+P2O5+K2O) nutrient is greater than 25% The organic matter content is 15%. Due to its inherent characteristics, organic-inorganic compound fertilizers have a wide variety of complex organic materials. Plants need to be selected based on local organic resources and must be fully fermented and decomposed. Inorganic nitrogen, phosphorus and potassium must be selected from urea, diammonium phosphate, monoammonium phosphate, potassium chloride and potassium sulfate with high nutrient content. Chemical fertilizers are mostly inorganic salts. If microbial agents are added to organic and inorganic compound fertilizers, the amount of chemical fertilizer added should not be too high, otherwise it will inhibit the activity of microorganisms. Depending on the formula space, soil conditions, and crop needs, moderate and trace elements can be added to develop crop-specific fertilizer varieties. The formula design can refer to the existing chemical compound fertilizer nutrient distribution ratio, but it cannot be copied, because the nitrogen, phosphorus and potassium ratio in the organic-inorganic compound fertilizer has its particularity. The main performance is that the nitrogen supply process of organic and inorganic compound fertilizer fluctuates less, is more stable and will not fluctuate greatly. The intensity and persistence of fertilizer supply were in harmony with the demand of fertilizer in each period of crop growth.The availability of phosphorus is high, it is not easy to be fixed, and potassium is not easy to lose. Therefore, the proportion of nitrogen in the formula can be appropriately high so as not to be too high, and the proportion of phosphate fertilizer can be appropriately low to prevent insufficient supply of phosphorus. Compound fertilizer 13-7-10 ≥ 30% is a better special fertilizer for fruits and vegetables, and the corresponding organic and inorganic compound fertilizer can be adjusted to 12-5-8 ≥ 25%, which can get better results.
The organic-inorganic compound fertilizer can effectively prevent the volatilization of nitrogen, the fixation of phosphorus and the loss of potassium because the organic matter fully absorbs the inorganic nutrients in the production process. more than 60%. Organic-inorganic compound fertilizer can be used as base fertilizer, top dressing or seed fertilizer. Seed fertilizer should not be in direct contact with seeds; as base fertilizer, the application rate is generally 50-150kg per mu; as top-dressing fertilizer, reference should be made to the amount of nutrient input in the season, and the application amount can be appropriately reduced compared with the base fertilizer; the fertilization period can be appropriately advanced to prevent greed and late maturity .