Greenhouse cellulose pad is one of the evaporative cooling intermediates used in the greenhouse wall and in general in industries using evaporative cooling systems.
These include poultry, home appliance and water cooler manufacturers, textiles, utilities and power generation industries.
The cellulose pad in the greenhouse is actually a good substitute for powders in evaporative cooling systems.
These systems are made up of various components and in addition to pads that can be made of cellulose or cellulose materials, including pumps, tanks, pipes and fittings, filters, ventilation fans, and so on.
How greenhouse cellulose pad works?
The greenhouse cellulose pad, also known as Media, Soldek, Cooling Pad, Cellulose Pad, and other names, is at the heart of evaporative cooling systems.
The cellulose pad of the greenhouse is made up of numerous thin layers of kraft paper that are arranged in a regular and wavy manner.
The most important feature of this product is its high water absorption. The presence of additives in the cellulose pad of the greenhouse increases the water absorption capacity.
Each cubic meter of cellulose pad absorbs about 100 liters of water and distributes the water on the pad in 4-5 seconds. They are also resistant to corrosion and corrosion by being saturated with anti-corrosion chemicals.
Air passes through the pores between the cellulose pad layers of the greenhouse perpendicular to the water flow. The regular texture and geometrical shape of the cellulose pad allow the water to flow evenly across it.
Water evaporates through the high contact surface of the cellulose pad of the greenhouse with the air stream, reducing the air temperature, thereby providing cool, healthy air to the greenhouse.
The cellulose pad of the greenhouse also has a frame. The pad frame is made of galvanized or aluminum sheet, which is also resistant to oxidation.
The pad frame consists of three parts: floor stud frame, top frame and top surface. The role of the pad frame is to collect the extra water that passes through the pad. The frame then directs the water to the tank and is then reused.
Greenhouse fan application and its types:
So far, the cellulose pad of the greenhouse has been explained. Another component of an evaporative cooling system is the greenhouse fan, which we are going to explain here and see what its use is and what its implications are.
It is essential to have a fan, especially in summer, when the warm air inside the greenhouse needs to be exchanged and cooled. Undoubtedly, excessive heat causes negative effects on plants and disrupts their growth and productivity.
The fan extracts the air inside the greenhouse and causes the air to flow through the greenhouse.
This is also necessary to provide the necessary carbon dioxide for the plant and to balance the moisture in the greenhouse.
The greenhouse fan is in two types: exhaust and circulate fan.
This type of greenhouse fan comes in sizes 100, 120 and 140, and naturally 140 is more powerful than the other two.
Exhaust Greenhouse Fan With Three Phase Engine (or Single Phase Customer Order), 6 Stainless Steel Blades 6mm, Copper And Resistant, 2 Hp Engine With 1400 RPM Outlet And Air Shift And the ventilation is 42,000 cubic meters per hour.
Mechanistically, the fan exhaust can be either a weighted damper or a clutch damper.
The feature of the clutch exhaust fans is that as soon as the fan is turned on, the dampers are opened by the clutch and unlike the weight damper fan, there is no need for air pressure to open them. These types of fans are best suited for humid areas to reduce greenhouse moisture.
This type of greenhouse fan, also known as a jet fan, is circular in shape and is usually mounted high above the roof of the greenhouse.
This fan model is also available in 40, 50 and 60cm sizes, preventing sudden changes in temperature and humidity in the greenhouse.
It also has a single-phase or three-phase motor with an output speed of 1,400 rpm and, like the 42,000 m3 / h fan, can pump and discharge air. This type of fan has a number of different blades and is available in 3, 4, 6 or 9 blades.
Greenhouse pad and fan:
The greenhouse pad system is one of the types of evaporative cooling systems that is the most effective way to reduce greenhouse temperatures in arid and semi-arid regions.
If used correctly, it will be able to reduce the air temperature inside the greenhouse by 10 to 20 degrees Celsius and provide the ideal temperature for plant growth.
The pad and fan system consists of a greenhouse cell pad with its frame assembly, a water supply system including a water tank, pumps and pipes, and a ventilation system including fans.
In this system, cellulose pads are installed on one side, and fans are mounted on the other side of the greenhouse.
The air temperature drops through the cellulose pad of the greenhouse and enters the greenhouse, and on the other hand, the fans draw hot air and air pollution.
As such, we face a temperature difference throughout the greenhouse, as we have the coolest air in the pads and will gradually warm up as we approach the fans. It should be noted that when the fans are working, all greenhouse doors and windows should be closed.
Prerequisites for setting up a greenhouse pad system:
Before any work, it is necessary to consider the components of the greenhouse cooling system such as the area required by the greenhouse cell pad, the number of fans, the pump capacity required, the tank volume, the amount of electricity required by various factors, and the mathematical calculation and use Estimate the relevant formulas by referring to the books on engineering and greenhouse management.
In fact, the efficiency of the system largely depends on the correct calculation and selection of these values, which is a specialized task requiring sufficient knowledge and experience.
There is also a formula for calculating many parameters of the greenhouse pad and fan system. For example, the formula for measuring the air temperature of the greenhouse cellulose pad can be used to measure this variable by using the efficiency of the cooling system and using two parameters (Tout dry temperature and Turbine temperature outside or Twb).
After the necessary calculations and estimation of the amount of equipment needed, it is time to install the system. Generally, installing a greenhouse pad system is not a difficult task and this is one of the benefits of these systems.
We also have a few things to consider while installing the system, some of which are listed below.
Notes on mounting cellulose pads for greenhouses and fans:
Usually, before installing the cellulose pad in the greenhouse, it is necessary to install two parts of the pad frame including the floor stud frame and the upper frame (the upper frame is installed after the pad is installed), as well as the water storage tank and water inlet system before installation. Installation of the pad and the installation process of the caps, water and pump outlet system, pump fittings and filters are done after the pad is installed.
The distance between the cellulose pad of the greenhouse and the fans, however, depends on the size of the greenhouse space, but the system does not respond to a distance of more than 60 meters. Ideally, a distance of about 30 to 50 meters between the pad and fan is recommended.
The pads should be mounted so that they are on the windward side.
The pads should be positioned so that they are not adjacent to the greenhouse fan, as the fan will draw the pad air into the other greenhouse. Unless the greenhouses are at least 15 meters apart.
As for the fans of the two adjacent greenhouses, either we have to mount them together or adjust them so that the wind does not blow against each other.
The fans should be two and a half times their diameter from the wall or other objects.
The fans and pads should be installed in such a way that there is no shade in the plant.
In areas where the weather is overly polluted, or brackish or heavy water, it is best to use a horizontal pad and fan system.
The length of the pads is also about 60 cm shorter than the length of the greenhouse.
Keeping in mind to prevent pad deposition is also effective. For example, replacing the water in the tank once every three weeks, reducing the power on and off, and preparing canopies for water, disconnecting the water every night for between 45 and 70 minutes in order to dry the pad in the event of deposition of the cellulose pad in the greenhouse. Use chemicals to wash it.
Smart control of greenhouse pad and fan:
It is also possible to consider specific settings for the greenhouse pad system through software so that the system can intelligently incorporate these settings into its performance.
For example, the pads can be switched on and off depending on the room temperature, or the pads can be set to allow 3 minutes for every 15 minutes of work. Or set a different temperature for daytime and nighttime fan lighting.
It is also possible to determine the degree of heat below which the pads are switched off and only the fans work or the fans turn on when the power is switched on and not all as soon as the power is turned on.
Some examples of greenhouse cellulose pad and fan system:
The benefits of using a greenhouse cellulose pad in addition to the utility and service it offers are also significant compared to alternative products. Some of the benefits of this product are listed below.
Because air cooling through the cellulose pad of the greenhouse occurs by passing air through the wet pad rather than directly transporting water droplets, this product avoids the transmission of many fungi and respiratory bacteria into the cooling space.
It works and provides clean and healthy air in the greenhouse environment.
The greenhouse cellulose pad is self-cleaning. As the air flows repeatedly along the grooves, the dust particles in the air are thrown into the water surrounding it and dumped into the tank with water.
This will prevent the deposition of the cellulose pad on the greenhouse. (It is better to say that this product has a lower deposition rate, not to be anti-fouling). In fact, these pads act as a filter for cooling systems.
The cellulose pad of the greenhouse has a long life span. (Between 3 and 5 years)
This pad prevents the insect from entering the area.
The cellulose pad in the greenhouse is cooler than the foil.
Greenhouse pads reduce energy consumption in the long run. (Due to low pressure drop in humid state)
The cellulose pad of the greenhouse is antibacterial and there is little chance for the fungus to grow and contaminate it.
The benefits of these pads are that they are available in different sizes and thicknesses.
These pads have a high standing and their rigid structure prevents them from falling.
It is easy to wash, install and maintain a greenhouse cellulose pad.
The greenhouse cellulose pad has evaporation efficiency of over 80%.
The advantage of the greenhouse pad system over the Fogger & Fan system is that the cellulose pad of the greenhouse is capable of using low quality water with a two to three percent runoff, but in the case of the Fogger it is necessary to have water. (Including low EC and TDS).
It can be said that the greenhouse cellulose pad is very environmentally friendly.
Because, in addition to not producing any pollutants or toxic substances and imposing on the environment, all the materials used are also naturally absorbable.
The cellulose pad of the greenhouse is light and its thickness is uniform throughout.
A few examples of the disadvantages and limitations of the greenhouse cellulose pad and the greenhouse pad system:
Greenhouse pad and fan systems and evaporative cooling systems in general require sufficient water and electricity.
The cellulose pad of the greenhouse loses its efficiency and efficiency by blocking its pores from being deposited.
If the cellulose pad in the greenhouse is pierced, this will cause air to enter and reduce the efficiency of the pad due to less contact between the weather.
In areas with high humidity, evaporative cooling systems are ineffective. Instead, in the hot and dry regions, these systems work best.
The cellulose pad in the greenhouse is more expensive than the foal. However, with the savings that these pads have on water and energy consumption and also because of their high shelf life and low maintenance cost, they can be very affordable.
Types of greenhouse cellulose pad:
The Cellulose Pad is available in the 7060, 5090, and 7090 models. But the cellulose pad of the greenhouse is actually the Model 7090, which is used for the greenhouse cooling system (as well as poultry farms).
Splitting the pads into these types is done in terms of the wavelength of the kraft paper layers in the cellulose pad and the angles of these layers relative to each other and provides different capabilities and applications for the cellulose pad.
In this model, the layers of paper with a wavelength of 7 mm overlap each other and form a 90-degree angle. The evaporation efficiency of this model from greenhouse cellulose pad is approximately 81%.
In this model of cellulose pad, layers of paper with a wavelength of 7 mm overlap each other to form a 60 ° angle (as the name implies).
This structure allows for increased cooling efficiency for the cellulose pad (approximately 87% efficiency) and works when higher air speeds are required (for example in gas turbines).
When the wavelength of the paper layers is 5 mm in the cell pad and they form a 90 ° angle, the cell pad is called 5090. This model is mostly used in cooling and cooling systems.
In these types of cellulose pads, a small pad is used in addition to the main pad and the upper pad to distribute water more evenly and thereby increase efficiency. The efficiency of this type of cellulose pad is also about 87%.
Finland cellulose pad, the best type of greenhouse cellulose pad:
Making the cellulose pad in the greenhouse requires some special technology, which makes it impossible to build it in many countries or that limited companies may be able to produce it.
Therefore, the greenhouse cellulose pad needed in these countries, including Iran, is supplied through imports.
The cellulose pad of the greenhouse of its highest quality usually belongs to Finland and is imported from Iran. Cellulose pads imported from China are also available in the market, which is not at all the quality of Finnish pads.
But, unfortunately, some vendors commonly refer to cellulose pads (even Chinese cellulose pads) as the Finnish cellulose pad, and even sell their Chinese products because of the high quality of the Finnish pad.
Greenhouse pad and fan price:
Below we will explain the price of greenhouse cellulose pad and the price of greenhouse fan.
Greenhouse cellulose pad price:
The price of a greenhouse pad, usually presented in square meters, depends primarily on the type of paper used. For example, the price of a greenhouse cellulose pad in Finnish paper is different from the price of a Taiwanese cellulose pad.
(Finnish paper is more expensive and therefore more expensive.)
The next effective factor in the price of the greenhouse pad is its thickness, usually producing and selling cellulose pads of two thicknesses of 10 cm and 15 cm.
Obviously, the price of a 15 cm thick greenhouse pad is higher than the price of a 10 cm thick greenhouse cell pad.
Also, the cellulose pad of the greenhouse is usually 60 cm wide and available at various heights. The height of a block of cellulose pads in a greenhouse may be one meter, a second, a 120 cm, a 150, or a 180 cm.
Usually this product is sold in terms of number of pieces and dimensions. For example, n pieces of greenhouse cellulose pads of 15 x 60 by 100 are ordered by the customer. The price of the pad frame is also usually presented in meters.
Although at the time of purchase it is necessary to inquire about the latest price of the cellulose pad from the seller, but for the information of the respected readers, we mention here the prices.
At present, the price of each square meter of greenhouse cell pad with a thickness of 10 cm in Finnish paper is about 280 thousand Tomans and Taiwanese paper about 200 thousand Tomans.
Also, the price per square meter of 15 cm greenhouse cellulose pad in Finnish paper is about 420 thousand Tomans and in Taiwanese paper about 300 thousand Tomans.
Example: If 30 pieces of greenhouse cellulose pads of 15 x 60 by 100 in Finnish paper are needed, the area of each piece is about 0.6 square meters and the price per piece is 420,000 USD per square meter of this type, It is estimated at around 250,000 Tomans, so the price of the 30 pads needed would be something like seven million and five hundred thousand Tomans.
Frequently sellers also set a minimum price for their product in terms of square meters or number of pieces and in fact do not sell less. (For example 20 square meters or 24 pieces) It should be noted that these products often have after-sales service and warranty.
The warranty is usually one or two years and includes certain items such as strength and durability. (Lack of deodorization and no doughing)
One of the things to consider when buying a greenhouse cellulose pad is to avoid cheating on cheaper products at low prices.
As we mentioned, the cellulose pad of the greenhouse is one of the products that is highly susceptible to counterfeit, given that the quality of this product will be known in the long run and there is no specific feature that will deter us from purchasing it.
The only way to make it easier to buy high quality and quality products is to visit reputable, reputable and experienced vendors who have already passed the test in this field, as well as inquiries from their former customers.
And asking for documentation of product importation from European countries can also help us in this regard.
Greenhouse fan price:
The price of a greenhouse fan varies due to the wide variety of products and different features that each have.
However, when purchasing, it is necessary to inquire with the seller about the exact price and to consider the exact features of the product compared to similar products.