SU1613443A1 - Method of producing slow-acting complex fertilizers for hothouses - Google Patents

Abstract

The invention relates to a technology for the production of mineral fertilizers and can be used to produce slow-acting complex fertilizers with full provision of the nutritious elements of greenhouse crops. The proposed complex fertilizer makes it possible to increase the degree of nutrient absorption by plants during the entire growing season, reduces the accumulation of nitrates in greenhouse products, and increases its yield. The urea-formaldehyde resin is pre-mixed with urea at a mass ratio of 1: (0.17-0.20), followed by the introduction of salts of trace elements at a mass ratio of urea to salts in terms of metal 1: (0.45-0.75), after which A nitrophosphate is introduced into the mixture at a mass ratio of a urea-formaldehyde resin with ammonium nitrophosphate ions 1: (0.06-0.08), the mixture is stirred at 60-80 ° C for 20-40 minutes. The slow-absorbing nitrogen component in the fertilizer when used is 50-60% of the total nitrogen of the fertilizer. 2 tab.

Description

This invention relates to a technology for the production of mineral fertilizers and can be used to produce slow-acting complex fertilizers with full nutrient supply of greenhouse crops.

The aim of the invention is to reduce the accumulation of nitrates in the soil and greenhouse plants, increase yields by increasing the degree of nitrogen absorption and providing plants with nutrients throughout the growing season.

The method is carried out as follows.

f .. ° ° C of a lightweight resin (KOS) is mixed with urea at a mass ratio of 1. (0.17-0.20), then trace elements are introduced into the resulting mixture at a mass ratio of urea to salts in terms of metal 1: (0.45-0.75) nitrophosphate as a nutrient containing nitrogen, phosphorus, potassium at a mass ratio of urea-formaldehyde resin with ammonium nitrophosphate ions 1: (0.06-0.08), the mixture is stirred at 60-80 ° C for 20-40 minutes

The first reaction of the interaction of the initial components in time is the complexation of normal salts.

trace elements with caroamide. An unstable complex is obtained, which, however, reacts with the methylol groups of the urea-formaldehyde resin during the second reaction / condensation caused by self-acidification of the medium. Formed stable urea formaldehyde (methylene) complexes are slow-convertible, do not interact with phosphate ions (which is also prevented by the increased content of metals in this mixture compared to phosphates). Ammonium salts nitrophosphate (NH4C1. NH4H2P04, (NH4) 2HP04 reacted with secondary methylol groups, their cleaved to form hexamethylenetetramine, is yuschiys simultaneously slow-nitrogen component and a nitrification inhibitor. Was recovered moiety with free acid lowers the pH of the mixture and causes condensation partially obezmetilolnoy resin with carbamide, with the slow-absorbing nitrogen compound, trimethylenetetracarbamide, having a high digestibility index being formed as the main product of this reaction. egulirovanie temperature and reaction time allows to reach its selectivity towards the desired product.

The fertilizer tablets proposed by the proposed method have the ability to evenly release all nutrients during the whole vegetation period (up to 6 months), increase the degree of nitrogen absorption (due to slow dissolution and inhibitory effect on the nitrification process with hexamethylentetramine) and trace elements (due to complex formation), reduces the accumulation of nitrates in greenhouse products (by reducing the amount of nitrates in the soil solution).

The method is carried out as follows.

127.5 kg of urea-formaldehyde resin (CFS) of KF-MT grade with a temperature of 55-85 ° C are introduced into the reactor and 20-28 kg of urea (mass ratio 1: (0-15-0.22)) are added successively with stirring. salts of microelements (MnS04, CuS04, ZnS04, MoS04, CoS04) in the amount of 23-65 kg (mass ratio of urea with metals of trace elements 1: (0.40-0.80) and 66-165 kg of nitrophoska dust (mass ratio of resin with ions ammonium (NH4 J nitrophosphate 1: (0.04-0.10). The mixture is stirred for 15-50 min at 55-85 ° С and a slow-absorbing nitrogen compound is obtained, which has a high index of absorption, containing a complex of microlements and the required amount of phosphate.

When using a slowly digestible nitrogen component, its content in fertilizer is 50-60% of all nitrogen contained in it. Properties of the obtained compound are presented in Table 1. Here are the comparative data with the prototype. As follows from the presented data, to obtain a product with optimal properties (the minimum content in cold water of soluble nitrogen and unassimilable metal phosphates, and the maximum content in soluble water of soluble nitrogen, and accordingly, with a maximum digestibility index) it is advisable to conduct the process at a mass ratio of urea-formaldehyde resin with urea 1: (0.17-0.20) and ammonium nitrophenium ions 1: (0.06-0.08), and the mass ratio of urea with metals of microelement salts is 1: (0, 45-0.75) at 60-80 ° C for 20-40 min.

Reducing the content of trace elements below the specified limit does not impair the quality of the product, but does not meet the needs of plants for 6 months. growing season.

Thus, fertilizers possessing the required properties are obtained with the order of introduction of components under certain conditions specified in the invention. Fertilizers manufactured according to the prototype and having the same ratio of nutrients with the proposed method do not provide a low content of soluble in cold water nitrogen and metals. the form of unassimilable phosphates and the maximum content of nitrogen soluble in hot water and the digestibility index.

In order to clarify the effect of the proposed fertilizer on reducing the nitrate content in the soil and greenhouse plants, as well as on increasing their yields, complex fertilizers were manufactured with the same N: P205: K20 ratio containing 45-65% of the slowly assimilated nitrogen according to the proposed method, as well as slow-growing fertilizers according to the prototype method.

The optimal ratio of NiPaOsiKaO in fertilizer depends on crop, soil, climatic conditions and other factors. When using cucumber fertilizers, 200 kg of nitrophosphate dust, 92 kg of potassium sulfate, 11 kg of bacteriological fat were additionally introduced into the slowly assimilated nitrogen component, the mixture was tableted and dried to a moisture content of 2%. Received 572.5 kg of slow-acting complex fertilizers containing,% 11 72 N- 5.36 P205; 14.29 K20 (2NiP205K20 31.7%) Of the total nitrogen content, 53.8% is slow absorbable. Data on the yield of cucumbers for 6 months. spring vegetation, fertilized 120g, 55gP205I 145g K20 per 1 m area of the greenhouse, as well as the dynamics of nitrate accumulation in the soil and fruits are presented in Table. 2. For comparison, regulatory fertilizer data is also presented (the basic object is the main fertilizer + 7-fold adjustment with liquid fertilizers) with the same nutrient intake.

From the data presented in table. 2, it follows that the basic object does not provide sufficient yield of cucumbers, and the accumulation of nitrates in products partially exceeds the sanitary requirements (300 mg / kg), and the average nitrate content is close to it. The prototype has operational advantages in comparison with the 2 basic objects (single introduction of fertilizers), however, during a long growing season the accumulation of nitrates exceeds the allowable norms and only at the end of the growing season the amount of nitrates decreases sharply, although this also accompanies a decrease in yield. The average nitrate content during the growing season is slightly lower than the base object, while the average yield is higher. 3

The proposed fertilizer with a content of slowly assimilated nitrogen of 50- 60% provides a 2-fold reduction of nitrates, and also significantly increases the yield. A decrease in the content of slow-digesting nitrogen up to 45% significantly increases the accumulation of nitrates, especially in

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the initial period of the growing season, and also somewhat reduces the yield. Increasing the slowly assimilated nitrogen to 65% has little effect on the accumulation of nitrates, and also reduces crop yields (some nutrients remain undigested during vegetation in the soil). Therefore, it is advisable to maintain the content of slow-absorbing nitrogen in the resulting fertilizer in the range of 50-60%, which is possible if the production technology used in the fertilizer is observed.

Claims (1)

Thus, the proposed method allows fertilizer to be introduced during the vegetative period, to reduce the accumulation of nitrates in products and to increase the yield. Claims The method of obtaining slow-acting complex fertilizers for greenhouses by shifting the urea-formaldehyde resin with nutrients containing nitrogen, phosphorus, potassium and trace elements, characterized by that. what. in order to reduce nitrate accumulation in the soil and greenhouse plants, increase yields by increasing nitrogen absorption and providing plants with nutrients throughout the growing season, the urea-formaldehyde resin is mixed with urea at a mass ratio of 1: (0.17-0.20) the subsequent introduction into the mixture of salts of trace elements at a mass ratio of urea and salts in terms of metal 1: (0.45-0.75), nitrophoska, used as a nutrient containing from phosphorus, potassium at a weight ratio of urea-formaldehyde resins, and ammonium ions nitrophosphate 1: (0.06- 0.08) and stirring at 60-80 ° C for 20-40 min. (Xj d: s c; Yu OJ table 2