The use of tempozil in the treatment of alcohol dependence. Urea - an effective nitrogen fertilizer Urea characteristics

In Russia, two grades of urea are produced - A and B. Grade A urea is intended for industrial use in the production of plastics, resins, and adhesives. Urea grade B is used in agriculture as a mineral nitrogen fertilizer and as a feed additive in livestock farming.

Product properties and technical specifications

Urea is colorless crystals, easily soluble in water, alcohol, liquid ammonia, and sulfur dioxide. Melting point 132.7°C, density 1.33.103 kg/m3.
Urea at normal conditions fire- and explosion-proof, non-toxic.
Urea is packaged in valve paper and polymer bags in accordance with regulatory and technical documentation. Bulk in hopper-type railway cars, mineral carriers, as well as in specialized metal containers. For retail the product is packaged in plastic bags weighing no more than 3 kg. Store in closed dry warehouses. Containers with urea and transport packages may be stored in open areas.
They are transported packaged and in bulk by all types of covered transport, except air.
Urea is produced in two grades: A - for use in the chemical industry and livestock farming, and B - for use in agriculture.
The table below summarizes technical requirements to urea according to GOST 2081-92.

Technical characteristics of urea (according to GOST 2081-92)

Areas of application of urea

Urea is a highly reactive compound and forms complexes with many compounds, such as hydrogen peroxide, which are used as a convenient and safe form of “dry” hydrogen peroxide. The ability of urea to form inclusion complexes with alkanes is used for dewaxing oil.
When heated to 150-160°C, urea decomposes to form biurethane, ammonia, carbon dioxide and other products. In aqueous solution it hydrolyzes to CO2 and NH3, which determines its use as a mineral fertilizer. When interacting with acids, it forms salts. Alkylation produces alkylureas, interaction with alcohols produces urethanes, and acylation produces ureides (N-acylureas). The latter reaction is widely used in the synthesis of heterocyclic compounds, for example, pyrimidines. Urea easily condenses with formaldehyde, which makes it widely used in the production of resins.
Chemical properties urea determine its widespread use in the chemical industry in the synthesis of urea-aldehyde (primarily urea-formaldehyde) resins, which are widely used as adhesives, in the production of wood-fiber boards (DFB) and furniture production. Urea derivatives are effective herbicides.
Part of the urea produced is used to produce melamine. A significantly smaller share is used for the needs of the pharmaceutical industry.
By its nature, urea is a mineral fertilizer that is used on all types of soils for any crops. This form of fertilizer provides a significant increase in crop yield. It is produced in this quality in caking-resistant granular form. Compared to other nitrogen fertilizers, urea contains the largest amount of nitrogen (46.2%), which mainly determines the economic feasibility of its use as a fertilizer for many crops on any soil.
The rumen of ruminants contains microorganisms that can use urea for protein biosynthesis, so it is added to feed as a protein substitute.
In medical practice, pure urea is used as a dehydration agent to prevent and reduce cerebral edema.
Interesting areas of application of urea are associated with its use for purifying emissions from thermal power plants and waste incineration plants, where the products of thermal decomposition of urea are used as a nitrogen oxide reducer. Moreover, urea can be used both in solid form and in the form of an aqueous solution. Today, this technology is already being implemented at waste incineration plants.
Another promising area for the use of urea is the production of the AdBlue product - a 32.5% urea solution used for treating exhaust gases diesel engines. The use of this solution makes it possible to achieve compliance of the composition of exhaust emissions with Euro-4 and Euro-5 standards. In this case, the use of prilled urea is more preferable due to its physical properties.

PRODUCTION TECHNOLOGY

Development domestic production urea

Urea was discovered by Ruel in 1773 and identified by Prout in 1818. Particular importance to urea in the history of organic chemistry was given by the fact that its synthesis by Wöhler in 1828 was the first synthesis of an organic compound from an inorganic one: Wöhler obtained it by heating ammonium cyanate obtained in situ reaction of potassium cyanate with ammonium sulfate.
All industrial methods for producing urea are based on its formation by the reaction of ammonia with carbon dioxide at temperatures of about 200°C and pressures of about 200 atm. and higher, therefore, in most cases, urea production is combined with ammonia production.
The first industrial installations for the production of urea abroad appeared in the 1920s on the basis of work carried out by chemists in Germany, the USA and France at the beginning of the 20th century. These installations operated according to the so-called open scheme: the urea melt was throttled to atmospheric pressure, at this pressure the unreacted gases were separated and the ammonia contained in them was used to produce ammonium salts, and then the urea solution was evaporated and urea was obtained in crystalline form. This method was extremely uneconomical.
Therefore, in the 1930s and 40s they were activated in different countries research papers, which were aimed at creating more economical methods for producing urea.
The beginning in the USSR industrial production urea dates back to 1935, when the first unit with a capacity of 240 kg per day was launched at the Chernorechensky Chemical Plant (Dzerzhinsk).
By the 1950s, there were two industrial installations for the production of urea in the USSR at the Novomoskovsk and Lisichansk chemical plants with a total capacity of about 20 thousand tons per year, created on the basis of the pre-war work of the State Internal Affairs Directorate, Leningrad, and operating on an open circuit. Research work in the field of improving urea production technology was carried out in parallel in several directions; schemes for the synthesis of urea with gas, partial and liquid recycling were developed. At this time, the Research and Design Institute of Urea (NIIK) was created, which designed and tested in 1958-59 in Stalinogorsk (Novomoskovsk) on a pilot industrial scale two processes - the process of two-stage distillation of urea melt with condensation and recycling of excess ammonia and the process of separating distillation gases by selective absorption of carbon dioxide in a solution of monoethanolamine. At the same time, together with ChKhZ, a process for continuous evaporation of urea solution and its crystallization in screw-type devices was developed and tested. These works served as the basis for the projects of the first, considered at that time large-tonnage, urea units with a capacity of 35 thousand tons per year with partial ammonia recycling (Novomoskovsk, Salavat, Angarsk, Grodno, Kemerovo) and full gas recycling (Shchekino).
Abroad during this period, the company Stamicarbon (Netherlands) developed and in 1959 brought to industrial implementation a process for the production of urea with complete recycling of unreacted substances in the form of an aqueous solution of ammonium carbon salts - the so-called complete liquid recycling - with the production of a granular product by spraying the urea melt in a hollow tower towards the upward flow of air.
Later, this granulation method was called “prilling”. Simultaneously with the construction in the USSR of the mentioned units with a capacity of 35 thousand tons per year, several sets of equipment were purchased abroad for units with a capacity of 90 thousand tons per year, operating using the technology of full liquid recycling from Stamicarbon. The workshops were put into operation in the period 1963-1965. at the Shchekino and Severodonetsk chemical plants, the Chirchik electrochemical plant and the Salavat petrochemical plant (workshop No. 24-1).
Based on the experience of developing these units, in the 1960-70s, projects were completed for more than 25 urea production units with a capacity of 90 thousand tons per year using full liquid recycling technology, including a project for re-equipping a workshop with gas recycling in Shchekino. Shops with two units were launched at the Novomoskovsk, Nevinnomyssk, Novgorod chemical plants, at the Salavat Petrochemical Plant (workshop No. 24-P), the Vakhsh Nitrogen Fertilizer Plant, the Kuibyshevazot Production Association, the Grodno Azot Production Association, the Ionavsky ZAU, the Kirovkan and Rustavi Chemical Plants. factories, as well as at the Angarsknefteorgsintez Production Association, the Chernorechensk Production Association Korund, in the city of Kokhtla-Jarve, etc. In total for this project for 1966-1972. 32 urea production units were put into operation.
By the end of 1972, the capacity of urea plants in the USSR exceeded 5 million tons per year - more than 30% of the world's total.
In the 1970s, by government decision, sets of equipment for units for the production of urea with a capacity of 330 and 450 thousand tons per year were purchased using technologies from all leading foreign companies.
Currently, the urea production industry is based on a scheme with full liquid recycling from TES (Japan), JSC NIIK, as well as on stripping process schemes from Stamicarbon, Snamproggetti (Italy) and Tecnimont (Italy).
Urea production plants are located in seven countries former USSR(Russia, Ukraine, Belarus, Uzbekistan, Lithuania, Estonia, Tajikistan). These plants employ five main methods of urea production: full liquid recycle AK-70 (31 plants), Stamicarbon CO2 stripping process (13 plants), Snamproggetti ammonia stripping process (3 plants), Tecnimont (3 plants) and TEC (1 installation). Regarding the technologies used, the capacities are distributed as follows:

Urea production technologies at enterprises of the former USSR

Source: "Chemistry and Business"

As can be seen from the diagram, liquid recycling technology is one of the most common in the territory of the former USSR (31%). For Russia this is even higher - 36%. In addition, three countries of the former USSR have only this type of urea production.
Despite the fact that the installations were built a long time ago, they are quite competitive. The measures taken at most enterprises to reconstruct production facilities increase capacity and reduce energy costs. This will be discussed in more detail when considering urea production technologies at Russian enterprises.

OVERVIEW OF MODERN TECHNOLOGIES

Characteristics of Russian production

Stripper for urea production using the Stamicarbon process

As mentioned earlier, in Russia, urea production is carried out using the technologies of Stamicarbon, Snamprogetti, Tecnimont, NIIK, GIAP. Initially, the development of urea production in the USSR was carried out by GIAP (until the 50s). After the creation of the Urea Research Institute, the institute began to play an important role in the creation and reconstruction of urea production. Russian enterprises subsequently began to widely use the technologies of the above-mentioned Western companies. The most common technology at the moment is the Stamicarbon process. Kemerovo and Berezniki OJSC Azot use Tecnimont technology. The initial technology at Mineral Fertilizers OJSC is TEC. A number of units (in particular, 1 of the 3 units of NAC Azot) uses Snamprogetti technology. More details about the production of urea at enterprises will be discussed in the next part of the subsection.
On the technology market for creating new capacities, there are various modifications of the stripping process, differing mainly in the hardware design of the synthesis unit. Foreign companies today offer installations with a capacity mainly from 1000 to 2000 and even 3000 tons/day.
All these technologies are at approximately the same level in terms of the degree of use of raw materials; they differ in different solutions for hardware design, used structural materials, and technological methods that allow minimizing the level of energy consumption. For example, the Stamicarbon company offers a flooded synthesis reactor combined with a capacitor high pressure. In TEC units, the synthesis stages and subsequent stages are combined in heat, which reduces energy consumption. OJSC NIIK, together with the Czech company Hepos, offers the supply of a plant with a capacity of 1200-1500 tons per day, which is based on modernized stripping technology.
Let's take a closer look at the Stamicarbon CO2 stripping process. A simplified process diagram is shown in Fig. 1.1.

Rice. 1.1. Stamicarbon CO2 stripping process

Ammonia and carbon dioxide are converted into urea through ammonium carbamate at a pressure of about 140 bar and a temperature of 180-185°C. The conversion of ammonia reaches 41%, carbon dioxide - 60%. Unreacted ammonia and carbon dioxide enter the stripper, with CO2 acting as a stripping agent. After condensation, CO2 and NH3 are recycled and returned to the synthesis process. The heat of condensation is used to generate steam for the CO2 compressor.
This process can have different hardware design. Below is the Urea 2000plusTM Technology - synthesis with a pool condenser.

Rice. 1.2. Urea 2000plus technology: synthesis with Pool Capacitor

This technology is successfully used in a 2,700 ton/day urea production facility in China (CNOOC), launched in 2004, as well as in a 3,200 ton/day capacity in Qatar (Qafco IV), launched in 2005.
The second embodiment of this process involves the use of a pool reactor. The advantages of synthesis using a pool reactor are:
- in this case, 40% less heat exchange surface is required compared to a vertical film-type condenser,
- the HP capacitor and the reactor are combined in one device,
- the height of the production structure is significantly reduced,
- the length of HP pipelines made of corrosion-resistant steel is significantly reduced,
- reduction in investment,
- ease of operation, stable synthesis insensitive to changes in the NH3/CO2 ratio.
Below is a diagram of this process.

Rice. 1.3. Urea 2000plus technology: synthesis with a flooded reactor

Rice. 1.4. Pool reactor diagram

At the moment, there are also developments of mega-urea plants with a capacity of up to 5000 tons/day. Below is a diagram of the mega plant proposed by Stamicarbon.

Rice. 1.5. Mega-production of urea (Stamicarbon).

A variant of the stripping process proposed by Snamprogetti involves the use of ammonia as a stripping agent. NH3 and CO2 react to form carabide at a pressure of 150 bar and a temperature of 180°C. Unreacted carbamate is decomposed in the stripper by the action of ammonia. A simplified process diagram looks like this:

Rice. 1.6. Snamprogetti NH3 stripping process

The final stage of all technological processes Urea synthesis is the production of commercial urea granules. Let's consider this process in more detail.
There are two main ways to produce granules - prilling and granulation. The prilling method involves cooling drops of urea melt located in free fall, and their crystallization in the counter flow of cooling air. The granulation method is reduced to spraying and subsequent repeated layering of urea melt onto “seed” (solid) particles of the substandard product with the formation of spherical granules and subsequent cooling of the latter. To obtain granules of nitrogen fertilizers, including urea, the most common method in world practice is prilling.
At the end of the twentieth century, a product appeared on the urea market, obtained by granulation in a “fluidized” bed and differing in its properties from prilled. Currently, the technology for granulating urea in a “fluidized” bed is offered by Stamicarbon, TEC, Jara and a number of others. The main advantage of granular urea is the higher strength of the granules and, accordingly, less caking during transportation. However, capital costs for the construction of a product granulation plant are on average 1.5-1.8 times higher than for prilling. In addition, the urea granulation plant is also characterized by a larger footprint, the presence of a large amount of retour (up to 50% of output), and relatively high energy and operating costs. However, today the growth rate of granular product capacity exceeds the growth rate of prilled product.
Below are the schemes for prilling and granulation in a fluidized bed using Stamicarbon technology.

Rice. 1.7. Diagram of the prilling process (Stamicarbon)

Rice. 1.8. Scheme of the fluidized bed granulation process (Stamicarbon)

The latter option for producing commercial urea is used in particular at GrodnoAzot (Belarus).
Considering that the competitiveness of urea production largely depends on the efficiency of ammonia production, we will consider modern technologies for the production of this product. Then we will consider in detail the production of ammonia and urea at Russian enterprises.

Urea (urea) is a chemical compound, the end product of protein metabolism. Human urine contains more than 2% urea. The composition of urea was established in 1818 by the English physician and chemist W. Prout. Urea is the first organic compound obtained synthetically from an inorganic substance. First synthetic method The production of urea was used in 1828 by the German physicist F. Weber. Currently, most often, the indirect method of obtaining urea from carbon dioxide and ammonia, developed by the chemist A.I. Bazarov, is used.

Composition of urea and its properties

Urea is a white, finely crystalline substance. Urea crystallizes from water in the form of flat prisms, easily soluble in alcohol and water, melting at a temperature of 160-190 °C. When heated to 200 °C, this compound turns into ammonium cyanate, and under the influence of more high temperatures at atmospheric pressure, urea decomposes to form carbon dioxide, ammonia, cyanic acid, biuret and other components.

Nitrogen is included in urea in an easily digestible amide form. Nitrogen in the amide form is well absorbed by the leaves and roots of plants. Therefore, urea is often used as a fertilizer. When urea enters the soil, the amide form of nitrogen is converted to ammonia and then to the nitrate form. This transition occurs quite slowly, so the absorption of nitrogen by plants occurs evenly.

Application of urea

Urea has a diuretic (diuretic) and dehydrating (dehydrating) effect. The substance prevents and reduces toxic pulmonary edema, cerebral edema, and helps reduce intraocular pressure.

A urea solution at a concentration of 15% is prescribed in the form of rinses, wet dressings, and irrigation of purulent wounds. Under the influence of this compound, wounds are cleared of necrotic masses faster and heal faster. The use of urea also allows for faster resorption of scars.

Adding urea to cosmetics at a concentration of 3-10% helps protect the skin from fungal and microbial infections. French researchers have determined that urea cream can protect the skin from negative effects environment for three to four hours.

Cosmetics containing urea usually have a short shelf life. This is explained by the fact that this compound easily draws moisture from the air.

In the food industry, urea is used as an additive that modifies and enhances the aroma and taste of food products. This compound is added to flour and baked goods in amounts of up to two grams per kilogram of product. Urea is added in the production of alcohol, and is also used in the processing of cotton seeds to neutralize gossypol.

Contraindications to the use of urea

Any addiction is a difficult test not only for the health and psyche of the patient himself, but also for his relatives. Alcoholism in our country is not considered a universal evil, unlike drug addiction, and this is fundamentally wrong. Alcoholism destroys the lives and families of patients just as much as other diseases. You can only heal if you have the determination and desire to start. new life. Chemicals such as disulfiram and calcium urea citrate, known in our country as Tempozil, can help you get on the path to a sober life.

Tempozil

Tempozil is a drug that causes aversion to alcohol. The drug has been quite widely known since the middle of the last century and was already used as maintenance therapy in the treatment of alcoholism in the USSR and abroad. Actually, none therapeutic effect Tempozil, like other coding methods, does not have, but nevertheless, for patients who decide to quit the addiction, this medicine helps them withstand a long pause, abstaining from drinking during this time.

The essence of the method

Tempozil belongs to the so-called aversion therapy, that is, a number of drugs that make it impossible to drink alcohol due to severe physical consequences for the body. Its active ingredient, calcium urea citrate, acts on enzymes that process ethanol. As a result of this effect, alcohol does not break down in the body into safe products, but freely “walks” through the organs, simultaneously poisoning the entire body. Considering the fact that ethanol is a powerful toxic substance, it is easy to imagine how a person who drinks a little alcohol after administering Tempozil will feel.

In cases where the patient, while under the influence of the drug, does not drink alcohol, his life and health are not in danger - the drug Tempozil is absolutely non-toxic and safe. Its sensitizing effect appears only after ingestion of products containing ethanol: fever appears, a rush of blood to the face and head, a strong heartbeat begins, cold sweat appears, a person can easily lose consciousness.

This condition is very life-threatening and very unpleasant for the patient himself. Having experienced such sensations at least once, the patient is afraid to take alcohol-containing drinks again. This is what Tempozil's action is based on.

Treatment

Tempozil is available in the form of tablets and injections. The drug is administered intravenously or prescribed orally, but only under the supervision of the attending narcologist. This severity is due to the fact that the medicine has many contraindications and, when prescribing Tempozil as a sensitizing therapy, the doctor must be sure of the patient’s full health and absence at the time of injection. alcohol intoxication at the patient.

After administering the drug in the required dosage, according to the instructions for use, the patient is given an alcohol test. The patient is offered alcohol in an amount of 20-40 ml. so that he can experience all the delights of drinking alcohol while being under the blocking influence of Tempozil. After such a provocation, patients are afraid to drink alcohol.

In fact, not a single drug administered intravenously can circulate in the patient’s blood for a long time. This is how Tempozil works. Its sensitizing effect lasts a short amount of time - no more than three days, so the patient must continue to maintain himself in a sober state either with the help of tablets that are used for no more than a week, or with the help of other means of aversion therapy.

Tablets can be prescribed to patients outside the clinic, but under the mandatory supervision of a narcologist, since patients’ failure to comply with the schedule for taking tablets and the dosage prescribed by the doctor can lead to a persistent decrease in the effect of the tablets and, consequently, to a possible relapse of the disease.

Efficacy of the drug

Tempozil can be used as aversion therapy only after. Only then, if the patient has a strong desire to lead a sober, healthy lifestyle, will the medicine show its effectiveness. The remedy itself does not have much long action, although the effect appears almost instantly - within an hour after administering the dose or taking the tablets.

Tempozil can be used as an adjuvant therapy only with a set of measures in the treatment of alcohol addiction, therefore, it makes no sense to use this medicine independently and, especially, to treat it without the knowledge of the patient. Moreover, self-medication can be dangerous to the health and life of the patient, since the medicine has a number of contraindications.

Contraindications

An absolute contraindication to taking Tempozil is the patient's pregnancy. In addition, intolerance to the components of the drug may make it impossible to use it as a sensitizing agent. Tempozil is also not prescribed to patients with heart pathologies.

It is strictly forbidden to take Tempozil for diseases such as:

• bronchial asthma;
• severe hypertension;
• pulmonary tuberculosis;
• liver diseases;
• kidney pathologies;
• emphysema;
• blood diseases;
• mental illness;
• malignant neoplasms;
• glaucoma;
• nerve inflammation;
• state of alcoholic intoxication.

Relative contraindications to the use of the drug are:

• age over 60 years;
• ulcerative lesions of the stomach in the acute stage;
• organic lesions of brain tissue;
• hypertension;
• minor endocrine disturbances.

In the presence of such diseases, a decision on the advisability of using Tempozil can only be made by a narcologist. Otherwise, you may experience serious side effects.

Side effects

When taking Tempozil correctly side effects is not usually observed in patients. However, long-term use of tablets can lead to exacerbation of the patient’s pre-existing diseases - gastritis, cardiovascular diseases, thrombophlebitis. In a number of cases, uncontrolled use of pills led to an acute mental disorder such as alcoholic delirium.

An old and time-tested fertilizer urea (urea) is used everywhere and is considered universal. In addition, it is part of multicomponent mixtures intended for complex treatment of fields and garden plots. This tool is one of the most popular and widespread options, and its cost is very affordable.

Composition of urea fertilizer

The chemical composition of this fertilizer has not changed for years. It's still the same Chemical substance 46% nitrogen. From a chemical point of view, it is a carbonic acid amide. It is formed under high pressure from carbon dioxide and ammonia gas. In the finished state, the fertilizer is a water-soluble crystallized substance of white color, sometimes with a yellowish tint. Available in the form of granules, packaged or weighed.

Using urea in the garden

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Like all fertilizers with a high nitrogen content, urea improves plant growth, increases productivity, and increases the protein content of grain crops. The peculiarity of this drug is also that it can be used as a means to combat plant diseases and wintering insect pests. These insects include the following species:

• apple blossom beetle;
• slowpoke;
• weevil.
  Among the diseases effectively eliminated:
• Scab;
• Purple spotting;
• Monilial burn.

Urea in bags

How to dilute urea for irrigation

Since urea is soluble in water, it is convenient to apply it by watering plants. But it is important to maintain concentration. For strawberries, cabbage, tomatoes and cucumbers it is 20-30 grams per 10-liter bucket. You will need to apply 1 liter of this solution per plant. The same solution is applied under currant bushes, and gooseberries will require a concentration twice as low.

Instructions for use of urea fertilizer

Urea is widely used in dry form, as well as. When sowing vegetable crops, 3-4 grams of the drug are poured into the garden bed and mixed with the soil. Mature trees, including cherries and plums, are fed with 120-140 grams of fertilizer. For apple trees, the dose is doubled. Urea is sprinkled on the surface of the soil and then the plant is watered.

Spraying with a solution is also widely used. This is done during the active growing season of vegetable crops, but before flowering begins. The concentration of the solution is 50 grams per 10 liters. But the amount of sprayed solution is only 3 liters per hundred square meters.

Application of urea fertilizer in spring

For each fertilizer, the timing of its application is important. Urea can be applied when planting potatoes and other crops, usually in mid-spring. But the treatment of trees and shrubs to protect them from pests is done a little earlier. This needs to be done before the buds open, and you can start immediately after the air temperature rises to +3-5 degrees. The solution must be concentrated (I use 0.5-0.7 kg of the drug per 1 liter of water).

In parallel with urea, you can also use insecticides, for example.

Fertilizer Urea (urea) - occupies a leading place among the many nitrogen fertilizers used in agriculture for pre-sowing and subsequent fertilizing of plants. This organic compound contains up to 46% nitrogen. It is mainly produced in the form of white or yellow-gray granules, however, recently production has been launched in the form of tablets, with a coating that ensures long-term dissolution in the soil.

Properties of urea

Urea is one of the most frequently chosen fertilizers by both gardeners and farmers. Outwardly, it is very similar to ammonium nitrate; when purchasing, you can distinguish it by first wetting your fingers and rubbing a ball of fertilizer between them, which leaves a feeling of soapy fingers. Urea is one of the most highly concentrated nitrogen fertilizers (its content is up to 46.2%).

Urea granules

It dissolves easily in water and soil solution, resulting in the release of volatile forms of the element. For this reason, urea granules cannot simply be scattered on the soil, especially in drought conditions, as this is a waste of time and money. The use of this agrochemical as a main or pre-sowing fertilizer involves its incorporation into the soil.

• When it gets into the soil, urea dissolves quite slowly, so excessive accumulation of nitrates in fruits is excluded.
• Has a beneficial effect on the growth of vegetative mass of vegetation;
• Urea increases the protein content in grain;
• Fertilizer helps increase productivity.

Foliar fertilizing with urea

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If there are signs of nitrogen starvation of plants, as well as in the case of shedding of fruit and berry ovaries, foliar feeding is carried out by spraying with urea from special garden sprayers. Before, which is used for the same purposes, urea has a significant advantage - it burns the leaves less. Foliar fertilizing with urea during the growing season is carried out at the rate of 3 liters of working solution per 100 m². The working solution for vegetables is prepared as follows: 50 - 60 g of urea per 10-liter bucket of water. For fruit and berry crops, the working solution is prepared at the rate of 20 - 30 g per bucket of water.

Containers of carbamide (urea)

Instructions for use of urea fertilizer

To provide the agricultural crop with the necessary amount nutrient element, you should strictly adhere to the dosage, which depends on the needs of a particular plant, the method of feeding, soil moisture, and its structure. If you focus on the application method, the instructions for using urea recommend the following standards:

• For vegetable crops: potatoes, tomatoes, garlic, as well as fruits and berries, strawberries and flower plants - dosage from 130 to 200 g per 10 m2. For cucumbers and peas, only 5-8 g are required.
• Pre-sowing application uses up to 4 g of urea in each hole.
• Feeding with undissolved urea granules is carried out in a dosage of 50 to 100 g for the same area. For fruit crops, the application rate is higher and is 150 g for young apple trees and 70 g for cherry and plum trees, as well as shrubs. A fruiting apple tree requires up to 250 g, cherry and plum - up to 140 g. Urea is applied to the tree trunks, followed by mixing with soil or abundant watering. The diameter of the application site for fruit trees and berry bushes is determined as the projection of their crown onto the soil.
• Perennial flower crops that require nitrogen to emerge from hibernation respond very well to early spring fertilizing (2 g/l). Urea helps to more quickly overcome stress after harsh winter conditions and build up new vegetative mass.
• For root feeding of cabbage, tomatoes or strawberries, prepare a solution of 2-3 g of urea and 1 liter of water with thorough mixing until completely dissolved. This volume is intended for 1 plant. For others, the concentration can reach up to 6 g/l with the consumption of the resulting composition per 1 m2.
• Spraying is carried out with a 0.5-1% solution of an agrochemical. To prepare it, 5-10 g of urea are dissolved in 1 liter of water. This amount is calculated for a small area, 20 m2. The same concentration is applicable for indoor plants.

Urea application rate

Preparation of urea working solution

Urea as a plant protection agent

Urea is very often used as an effective means of controlling garden and vegetable pests. In the middle of spring, but before the buds begin to swell, a urea solution is used as a means of combating wintering insects: aphids, weevils, copperheads, etc. Beginning gardeners need to know how to dilute urea to prepare a solution used in the destruction of pests. To do this, 500 - 700 g of a concentrated urea solution is diluted in 10 liters of water and a garden or garden area is sprayed.

Urea is also used to protect plants from scab, purple spot and other infectious diseases; spraying is carried out during the initial period of leaf fall, in the fall. The foliage of fruit-bearing trees and berry bushes, as well as already fallen leaves, is processed. The solution is prepared in the same way as for killing harmful insects.