Sprinkling systems are an integral part of production greenhouses. The work of the entire greenhouse plant depends on their quality and efficiency.
In Russia, sprinkling systems are built on the principle of two tanks. The watering plant includes: 1) a mixing tank, 2) a system pump that supplies nutrient solution to the greenhouse; 3) Basic pump, which supplies water to the mixing tank. The base pump is also responsible for the fertilizer placement. The settings are, as a rule, identical, only the sizes are very different. In the system of pipes installed injectors, which are usually three. Each of these injectors has its own separate tank, which contains a mixture of fertilizers, usually called A, B, and C. Tank C is used to dissolve the acid in it, it is responsible for regulating the acidity of water and nutrient solution. Tanks A and B contain fertilizer solutions. The solutions in these tanks are concentrated, on the solubility of salt in water. For example, 220 kg of calcium nitrate can be dissolved in a cistern, we get a very strong solution in which the density is 1.4 - this is much heavier than water, but it allows for accurate dilution with the help of a computer to create a nutrient solution with a given concentration and acidity.
Injection of fertilizers occurs through controllers. Fertilizers are injected with water into a mixing tank. At this stage, we cease to control the composition of the solution. We calculated, we filled the necessary quantity of fertilizers in each of the tanks, but in the mixing tank we can no longer control how much there is nitrogen, phosphorus, potassium and other elements. We can control only 2 parameters: pH and concentration. All further management of watering ceases to take into account the concentration of each of the trace elements. You can take the finished solution to the laboratory and make a final calculation, but at the moment you can only control 2 parameters. You can also control the temperature, but you do not need it, because it controls the heating of water in the range of plus or minus 2 degrees.
Concentration and pH are two very important parameters, so calibration of the sensors that control them is very important. These sensors are very sensitive, for example, in a pH sensor there is only a glass membrane of 40 microns. If you are mistaken in calibrating the concentration or acidity sensors, you can lower the acidity of the solution by one unit and instead of the solution 5,5, for example, apply 6.5, which entails the precipitation of chelates and changes the composition of the solution, because you have more bicarbonates.
And here everything depends on the quality of the watering plant, which is different. There are a lot of plants, there are installations of Russian production, there are Dutch, Danish, Israeli. There is no unification of these installations in the country, but they all work on the same principle. We do not control anything after dissolving fertilizers, except for two parameters (concentration and pH).
Another on the watering unit is a counter, which considers the number of liters poured per hectare. Depending on how the irrigation stations are opened inside the greenhouse, we can find out how much nutrient solution has poured out on each valve. Knowing how many plants there are, we can determine how much nutritional solution is poured into one plant.
Practically all Russian greenhouses there is no fourth contour, though it should be. There should be a tank D, which would supply cyclically or permanently a microdose (2-10 ml / cube) of stimulant through the injector, and then the washing will not work cyclically, and you will always have the necessary element in the nutritional solution. If other tanks are 1000 liters, then this should be 10-50 liters. In this solution, stimulants, inhibitors, biopreparations and fungicides can be used, for example, Fundazol, Previkur. Now you cannot add any stimulant to the tank A or B, just in the tank for insertion.
"Thumbelina" is a simple installation for single-channel fertilizer application, it has: one set of tanks (A, B and C), three injectors, a mixing tank, a system pump and a control module. The watering installation of Sercom is also single-channel, has three external dispensers. Dispensers have patents. This is a very common watering installation in Russia. To do something else, there must be a microdoser. And people are already redesigning their installations and installing microdoser. The more up-to-date three-channel installation of Van Den Hoek, which has three pumps, three channels, a base feed pump, a mixing tank, a filter and a drainage substitute. This is one of the best installations.
I believe the most popular watering plant in Russia is "Prima", followed by Sercom and "Agrotechdetali". There are few Headindorskovkiy installations, they are set up at greenhouses Magnita, Izovol, Belogorie, Lukhovitskie Ovoschi, Seim Agro, and Agro-Invest. Agropark has Sercom . "Hedindorf" is a very good watering installation, but it is also very complicated. The core of the program is known to only 8 of the 700 who are involved in the production. The Dutch do not teach even their own, so the instructions have to deal with themselves. "Thumbelina" is the level of the 90's in the Netherlands. They develop, improve, but they do not come close to Hedindorf.
The drainage accounting system controls how much it merges into the trough, what concentration and acidity. This system is located directly inside the greenhouse. It allows in the semi-automatic mode to record drainage. Depending on what concentration of the nutrient solution, in each liter of water, usually contains from 1.5 to 2.5 grams of fertilizer per 1 liter of water. You can count how many fertilizers you have spent, and how many they went into plants, but how many have returned to secondary circulation.
According to the old method of production of one kilogram of products, it is necessary to spend 60 liters of water. A new technique to which the whole of Holland aspires to be - 22 l / kg of products. How do they want to do this? They are now trying to save energy very much, respectively, the average daily temperatures are lower, they water less, the consumption of water and fertilizers is less, buttocks are opened less often. In our climate, it is very difficult to do, because we have a continental climate, and in the Netherlands, Belgium, it is coastal. They have a day-night difference of 5-6 degrees, and we can make 25-30 degrees and the more this difference, the more difficult it is to grow a crop.
We do not have a legal basis for drainage drains - I can drain a bunch of drainage from any plant. In Holland you cannot drain anything, therefore, they put such methods, such revolutions, which do not allow to remove fertilizers outside the greenhouse. Therefore, they can grow 60 kg of tomatoes from 1 m2 and spend 11 tons per hectare of fertilizer per year.
If we take 100% of what was poured into the mat, a good indicator among agronomists (in Russian and in the Dutch years 15 years ago) is considered to be at the output of 15-20%. Nowadays a technique is used when all the elements that are not perceived by the plant (for example, Chlorine, Sodium, exudates, chemicals) are washed away from the mother by excess water. All this is washed out in a large tank called Drain Water ("Drink Water"). What do we do with him? We pour out, and modern greenhouse combines have another tank, which is called "Clean Water". There are cleaning plants between these two drains.
Water enters the UV installation for ultraviolet treatment. Special quartz lamps, which allow burning nutrient solution to kill all microscopic organisms: bacteria, fungi, viruses. Typically, the power of such a lamp is from 3-4 kilowatts, it is a very rigid ultraviolet that burns all the living things that are in the water. After processing, the water accumulates in a clean tank. Unfortunately, such an installation is not perfect. It is desirable to have a thermal disinfector, which, by shock heating up to 90 °C, and subsequent sharp cooling to 20 °C, allows the destruction of pathogens. After ultraviolet and thermal disinfector of ferrum and other chelates in the solution does not remain. In a clean tank we get a solution containing mainly macro nutrients of plants, while trace elements fall into the precipitate. From "Clean Water" in tanks is filled 20-30%, and the remaining 70-80% - is pure water. With such a ratio of ferrum, it is necessary to use 20-30% more, because the ferrum from the drainage has fallen into the precipitate.
The Dutch device that shows the EU, the pH and humidity of the mat is sold at prices from 1000 to 5000 euros and "floats" in 5 days. This is a small, beautiful toy that is very fond of selling us to Russia, but, unfortunately, it needs to be constantly cleaned, re-installed otherwise it grows up with salts and starts to "swim" in figures. For this money it is better to buy a weight control of mats of Russian production, any of the companies, which allows more accurately and throughout the season to monitor the moisture of mats. The Dutch are very much promoting their device, but ours found a simpler way - to put scales.
Weight control of the mass controls irrigation. Plants for mass control are issued by several companies: "Etiass", "Stroykomplekt" in Russia and foreign "Pascal control system". The Pascal system is used to control the weight of mats in real time, and the weight of mats depends directly on the amount of water that is present in it. The amount of this water tells us what moisture is mats. By schedule on the computer you can control how much, when, and what water has come or gone.
Over the night the weight of the mat gradually decreases. With the sunrise, you gradually lift the weight of the mat, reaching a certain volume in three to four hours before sunset, after which gradual weight loss is again gradual. If at midnight it is about the same value that was a day ago, then this is a neutral influence. If this line drops below, it means that you are drying the mat, if it remains higher, then you have water filling of the mat. With such weight control, you can control the plant. The strategy of irrigation, each day it looks different, depending on the weather: it was sunny or cloudy.
Russian cotton wool has now become not worse than foreign analogues. It does not require a special approach, but requires understanding. For example, there is a simple "Grodan" cotton wool called Whiton - you will never spoil it. You have cut through it drainage and you can pour it into it, as long as you want, you will never utter it, it will pour out everything, but it increases the percentage of drainage output, respectively, the loss of fertilizer, the loss of all components, and the Master keeps the water well, and "Expert" is something of an average between them. It all depends on the tasks set. How many drainage holes you have made, how you can water, how you can control, which methods you control - everything depends on it. There are currently 4 watts in Russia and two more imported, plus Belarusian cotton wool.
The osmotic installation allows you to get clean water without bicarbonates, which reduces the amount of acid. The water after this installation is mixed with ordinary water to obtain an average content of bicarbonates, since 1 liter of water after osmotic filtration costs 1 ruble. And if you spend 2.5 m3 per 1 sq. M of area, and you get 6 thousand Rubles of products, then at cost, such water can be up to 30% of the cost of products. It is impossible to use water that is cleaned from bicarbonates, because its pH can vary in the range of 2-3 units, therefore it is necessary to have bicarbonates from 1 to 2 mmole. Therefore, it uses it neatly and places low-power installations to solve specific problems. For example, if you make a solution for treatment, there is always a need for soft water, because if you use hard water with 7 mmoles of bicarbonate, the amount of chemical preparation can be 1.5-2 times higher than that of soft water. If you pumped 1000 liters of soft water, then adding two times less of the product, you get the same effect. For example, if you take soft water and Vertimec at a minimum concentration, after treatment against the spider mite, there will be no pest. And if you take the usual water and the average dosage of the drug, then the population of the pest will only be reduced by half. You always have to have cranes to fill Empas - this is a completely different water.
Also, non-carbonate water is used for Pad and fan cooling and humidification system. Water for evaporative cooling systems should not contain batteries and evaporates well, and it evaporates well if it contains the minimum amount of salts. Therefore, the osmotic installation should be in the greenhouse, but watering this water is not recommended because of the high cost. Such plants contain pH indicators that allow you to control the acidity of the water - leave it at level 6, preserving a certain amount of bicarbonates. A thermodynamic fan may be installed.
Thermal disinfectant is the main means of protecting the crop from diseases such as crazy root (Agrobacterium) or Ralstonia. Thermal disinfectant has a high cost of water treatment, as it is necessary to heat a cubic meter of water up to 90 ° C, and then to cool sharply to 20 ° C. It consumes a lot of energy, and this is the gas flow, so the disinfector should be, but use it in a critical case. The Dutch mainly use UV units, because they are cheaper, but not all of them can kill. For example, a viral disease of tomatoes and some bacteriosis passes UV-unit.
Rain water can be stored and used in a greenhouse to save on the consumption of other water, as well, because it has a low content of bicarbonates, and therefore, it requires very little acid.
The sand-gravel filter cleans the water that goes into the greenhouse, from large impurities. After this filter, the water does not contain any parts of the organic matter and the suspension. All that goes after the sand-gravel filter should be disinfected, since it constantly flows water, oxygen flows, and accordingly many pathogens can exist when water and oxygen arrive in a porous medium of sand and gravel mixture. The filter can be a nursery of fusarium, pythium and other pathogens. This filter is the main source of infection of greenhouses. If you once have infected this crazy root filter, then it will spread the pathogen throughout the greenhouse combine through the water. To avoid this, after this filter, there should be a UV cleaning on the water entering the greenhouse. I do not know any plant with such an installation in the territory of the Russian Federation. For the Dutch, any water that comes to the plant passes through the UV cleaning system.
From the seminar, Alexander Yurievich Shagaev - agronomist and consultant with 15 years of experience in greenhouses.
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