Dryer for vegetables and fruits with their own hands. Dryer from refrigerator

A do-it-yourself dryer for vegetables and fruits from standard purchased parts will be no worse than an industrial one.

Homemade drying chamber

Before you start making a dryer for vegetables and fruits, read the main requirements for drying. You can dry any fruits, vegetables and fruits that contain moisture:

• berries;
• mushrooms;
• apples;
• fish.

The principle of drying is simple and has long been known. Under the action of temperature, moisture is removed from apples, vegetables, berries and fruits. Therefore, a constant temperature of 50 to 60°C must be maintained in the dryer body while removing moisture. For juicy fruits, a one-hour drying mode at a temperature of 60 ° C and subsequent hours from 50 to 55 ° C is provided. How to make an electric dryer will consider in this article.

What are the designs of dryers

There can be many reasons for making do-it-yourself dryers of different volumes and capacities for vegetables and fruits: they are not satisfied with the performance, high price, high energy intensity, and others.

There are three options for making do-it-yourself dryers for vegetables, fish or fruits:

• electric;
• on wood;
• solar.

Other versions of homemade products, such as sublimation, UHF, infrared, using vacuum, will not be considered due to the complexity of manufacturing.

Of the three options presented above, only electric can work in automatic mode.

On wood and solar require the presence of a person and adjustment can only be carried out by sliding gate valves to regulate the inflow and removal of air.

Let's consider the manufacture of a dryer with a capacity of 50 to 100 kg of wet weight of the product at home, based on the fact that the home craftsman plans to sell some of the dried products.

Energy intensity

A factory dryer with automatic processing of dried apricots consumes about 1.6 kWh of electricity per 5 kg of raw product and dries for 36 hours.

Based on the average data, the jack of all trades should take into account that a home-made dryer for processing 50 kilograms of a raw apricot type product will consume 16 kW of electricity, and 32 kW for 100 kg. By simple mathematical operations, you can find out the future costs of cooking 1 kilogram of fruit.

For domestic consumers, the maximum power consumption of 3 kW / h is provided. Accordingly, 16 kW can be taken from the line in 3 hours, and 32 kW in 6 hours of continuous operation. But for 3 or 6 hours to dry products with a high water content will not work.

Conclusions: in domestic conditions, it is not problematic to build a dryer with a capacity of more than 50 kg of dry product if there is no limitation in electricity consumption. Accordingly, if someone decides to build a dryer for 100 kg, then he will have to increase the drying time by 1.5 times. And then 100 kilograms of raw product will have to be dried for 3-4 days with an increase in electricity consumption up to 32 kW.

Do-it-yourself electric dryer for fruits and vegetables

To do this, you need to make an electric dryer case, buy a fan, a heating element, a temperature sensor (thermostat), a time relay, two chimney draft regulators.

Tips: Before you start building a dryer with a power input greater than 3 kW, ask your local power company about the maximum power they can provide you.

Fan

For our purposes, household smoke exhausters for boilers are best suited.

Smoke exhausters for household boilers

Their distinguishing feature is that they can pass air with temperatures up to 150 ° C through themselves without damage to the electric motor. An ordinary axial fan is not suitable for these purposes. It is not able to work at 50°C for a long time. The diameter of smoke exhausters starts from 150 mm. It is necessary to place an electric heating element with an open spiral in the pipe coming from the smoke exhauster.

Tips: you can buy a fan for snail-type boilers with a capacity of at least 50 times the volume of the drying chamber.

Electric heater for dryer

For maximum heat removal, the heating element must be with an open spiral. The power is calculated based on the allowable rated power for the house and is equal to 3 kW minus the power of the fan of the smoke exhauster and household appliances. If this rate is exceeded, then the automation will work and turn off the light in the house.

Open coil electric heater

When choosing an electric heater, consider its dimensions. It must fit in a pipe that is connected to a smoke exhauster or a fan that supplies air to the drying chamber.

Smooth thermostat

Thermoregulators with smooth temperature control from 0 to 300°C are a standard part of all household electric furnaces. It must be connected in series in an electrical circuit with heating elements and a fan. When the required temperature is reached, it will automatically turn off the heating and the fan.

Household thermostat

You can use a thermocouple from ovens.

Where to buy a thermostat? There are several purchase options:

• online store;
• the nearest workshop for the repair of household appliances.

It is quite possible to purchase a thermostat at a flea market.

Time relay

In order to fully automate a home-made dryer, you need to buy an electronic two-channel time relay with programming for a week.

There are many options for execution and programming of the time relay and everyone can choose the right one for themselves.

By connecting a fan and a heating element to the time relay, you can set up its operation empirically. To do this, you need to set the time for turning on the heating element and the fan.

Chimney draft regulator

Draft regulators are installed in stainless steel chimneys. This automatic device is a precisely fitted valve on an axle. In order for it to be always closed or open, a small load is installed on one of the sides.

Install these two valves in the inlet and outlet ports of the dryer. When the fan is off, they will close the inlet and outlet of warm air under the weight of the load.

draft regulator

The use of these valves will automate the intake and supply of air without the use of actuators and expensive controllers.

For especially advanced jacks of all trades, we recommend buying a programmable controller. This equipment is more complicated, but it allows you to automate all drying processes, connecting humidity, temperature sensors, motors, slide gates and other actuators. They are widely used for lumber drying kilns.

When building a drying compartment, use the following materials for the frame:

• wooden slats;
• chipboard;
• wood fiber boards;
• oriented strand boards;

To insulate the drying chamber, use:

• polystyrene boards;
• mineral wool;

Please note that the insulation is installed from the outside, not from the inside!

Homemade drying chamber

To fix the insulation, use:

• glue Titanium, mounting foam for polystyrene foam boards:
• plastic fungi for mineral wool.

Close the insulation with a fiberboard board or seal it with self-adhesive aluminum foil. In extreme cases, it can be plastered with plaster on a synthetic mesh. It is sold in hardware stores for insulating houses.

If there is no necessary woodworking equipment to stiffen the frame, use metal corners for window frames.

metal corners

It is better to connect a wooden frame with screws than with nails.

Please note: to calculate the cross-section of wires, there is such a rule: for 1 kW you need 0.7 mm 2 of the cross-sectional area of ​​\u200b\u200bthe wire. Thus, for a drying chamber with a rated power of 3 kW, the cross section of the wires must be at least 2.5 mm 2.

Dried fruits

For safe operation, the metal parts of the dryer must be grounded.

When calculating the volume of the dryer, design a load per pallet of no more than 5 kg of wet product. If pallets are placed at intervals of 10 cm, then the height of the chamber for 20 pallets will be 2 meters. In this case, there may be a problem with loading at high altitude.

To combat mold and other diseases that occur in a humid and warm atmosphere, use a UV lamp.

For long-term storage and storage of food products for the future, various methods of their processing are used - drying, drying, smoking, salting. Often processing processes involve air drying. Some foods that contain a lot of water are heat-treated, that is, they are dried at a fairly high temperature in the oven (melons, apples, some fruits). Many other products are dried in the wind or in the sun (fruit, fish, poultry, ham, salted meat). An excellent alternative to such methods is a do-it-yourself mushroom dryer, which can also be used to harvest other products. Consider how convenient such a device is and how you can assemble it yourself.

Harvesting difficulties

Certain difficulties and inconveniences are associated with the drying process. It often happens like this: just put the products to dry, when suddenly the wind subsides or the sun hides, or even it starts to rain, and all the work goes down the drain. But the greatest evil in the summer is associated with flies. They swarm around the exhibited product and before you blink an eye, they will lay their eggs in it. In this case, do-it-yourself dryer for mushrooms will save you.

Important! Flies are malicious carriers of infection. Contacting these insects with products is simply unacceptable. It is because of this that many people wrap fish and meat preparations with gauze before hanging them in the sun or wind, however, this does not always guarantee reliable isolation from flies, and with a slight wind it can make the drying process difficult.

Anglers have particular difficulties, because after a good catch and salting of the caught, it is simply unrealistic to wrap each fish with gauze to dry, and the probability of damage to the product by flies increases significantly, especially if the fish is plastified. But still, there is a way out.

After many experiments, a wonderful solution was found - to make a dryer for mushrooms with your own hands, resembling a matchbox in shape, or rather, a lid from this box, only several tens of times larger.

Dryer Option #1

The device of the dryer and the principle of its operation is quite simple. To make such a dryer, you should:

1. From the rails, make a frame in the form of a parallelepiped.
2. Place it on its edge (matchbox gray side down).
3. Sheathe both side, as well as the lower and upper faces with solid material (oilcloth, roofing material, cardboard, plywood). Moreover, the upper face will be a hinged lid, like a piano lid.
4. Tighten the end faces with gauze or fine mesh.
5. Along the side walls inside the dryer, stretch the wires to hang the products.
6. Inside, on one side, directly near the gauze, install a table room fan, and pass its conductive wire through the gauze, leaving no free passage in it, and bring it out to the outlet.

Device Application

Food products should be put on metal hooks and hung on stretched wires. After a complete check and the expulsion of all flies, the lid closes and the fan turns on.

Important! The intensive air flow created by the fan ensures fast enough drying of products in compliance with sanitary requirements.

As a rule, the duration of drying in a dryer for mushrooms is determined empirically. It will depend on the humidity of the surrounding air, its temperature, as well as on the size of the products to be dried, their moisture content and the desired final moisture content.

• The dimensions of the dryer can be arbitrary and depend on the amount of product intended for drying.
• In order to reduce energy consumption, it is recommended to use fans that have several operating modes, which will make it possible to change the ventilation mode in the dryer.
• You can install such a dryer almost anywhere: on the veranda, balcony, under a canopy or even on the street.
• It is better to load products in the evening or early in the morning when there are no flies.
• Larger parts of the products are best hung closer to the fan first, and then they can be swapped.

Important! Many years of operation of dryers of this type made it possible to study their work in different conditions. Remarkable results were obtained in drying fruits, churchkhela, low potatoes, dill, parsley, salted chickens and ducks, boiled sausages, hams, and dried mushrooms.

Dryer Option #2

Let's look at another option, how to make a do-it-yourself mushroom dryer over a gas stove. So let's get started:

• For work, we need aluminum corners of various lengths and a wire mesh.
• To begin with, measure the dimensions of the plate in order to make a dryer, which can later be placed on its surface.
• Drill holes in the corners with a drill or electric drill so that they can be fastened with bolts and nuts.
• Now it came to the grid on which the mushrooms will be placed. Cut it to the size of the slab and the frame itself, with a margin.

Important! A net made of bandage, gauze or plastic will not work, as it is dangerous to hold such materials over a fire.

• In order to fix the mesh to the frame, use the same aluminum corner, but smaller in size. It should turn out so that from below the grid fits onto the platform from the frame, and from above it is pressed against the patch plate.
• Attach the plate to the frame with the screws through the pre-drilled holes.
• The height above the fire should be determined independently, it can be approximately 60-70 cm (just saw off the legs of the required length).
• Lay out the mushrooms, turn on the gas and that's it, the process has begun.

Important! Never leave gas unattended.

For long-term preservation and storage of food products for the future, they resort to various methods of their processing - salting, smoking, drying, drying, etc.

In most cases, processing processes involve air drying. Some products containing a lot of water in their composition are subjected to heat treatment, that is, they are dried at a high temperature in the oven (some fruits, melons, etc.)
Most of the products are dried in the sun or in the wind (salted meat, ham, poultry, fish, many fruits).

Certain difficulties and inconveniences are associated with the drying process. It often happens like this: just put the products out to dry, when the sun suddenly hid or the wind subsided, otherwise it suddenly started to rain, and all the work goes down the drain. But the biggest evil in the summer is associated with flies. They swarm around the exhibited product and can very quickly lay their eggs on it.

Flies are vicious carriers of infection. Contact of flies with products is unacceptable. That is why, before hanging meat and fish preparations into the wind, some people wrap them with gauze, but this does not always provide a reliable guarantee of isolation from flies, and in light winds it makes the drying process difficult.
Anglers are experiencing particular difficulties.

After a successful catch and salting of the caught, it is unrealistic to wrap each fish in gauze to dry, and the likelihood of spoilage by flies is very high, especially if the fish is plastovaned.

But there is a way out.
After a series of experiments, an excellent solution was found.

We made a dryer with our own hands, resembling a matchbox in shape, or rather, the lid of this box, but only several tens of times larger.

How the dryer works
The device and principle of operation are very simple. From the rails, a frame is made in the form of a parallelepiped, placed on the edge (matchbox gray down).

Both side, as well as the upper and lower faces, are sheathed with solid material (plywood, cardboard, roofing felt, oilcloth, etc.), and the upper face is a hinged lid (like a piano lid). The end faces are covered with fine mesh or gauze.

Inside the dryer, wires are stretched along the side walls for hanging the product. On the one hand, inside, directly at the gauze, a table room fan is installed, and its conductive wire is passed through the gauze without leaving a free passage in it and is brought out to the electrical outlet.

Food products are put on metal hooks and hung on stretched wires. After a thorough check and expulsion of flies, the lid is closed and the fan is turned on.

The generated intense air flow ensures a fairly quick drying of the product in compliance with sanitary requirements.
Drying time is set empirically. It depends on the ambient temperature, its humidity, as well as on the size of the product to be dried, its moisture content and the required final moisture content.

Homemade dryer dimensions

The dimensions of the dryer are arbitrary and depend on the amount of product intended for drying. In order to save energy, it is desirable to use fans with several operating modes, which will allow you to change the ventilation mode in the dryer.

You can install the dryer on the balcony, on the veranda, in the barn, under a canopy, even in the open air. Loading products is best early in the morning or in the evening when there are no flies. Larger parts of the products should preferably be hung closer to the fan first, then they can be swapped.

The long-term use of such a dryer has made it possible to comprehensively study its operation under various conditions.

Excellent results were obtained in drying mushrooms, drying hams, boiled sausages, salted ducks and chickens, drying bunches of parsley, dill, low potatoes, churchkhela, fruits, marshmallows poured into baking sheets, etc.

The useful work of the dryer when drying fish is simply difficult to overestimate.
I think many will be interested in such a dryer, because the material used for its manufacture is actually junk, the work is simple, there is a fan in almost every house, the power consumption is low, and the benefits are great.

Drawing homemade dryer

About drying apples ...

Some readers claim that when dried, neither vitamins nor beneficial trace elements remain in apples. Is it so? Yes, something is destroyed during drying, in particular, vitamin C. But most of the useful substances are preserved: potassium, calcium, phosphorus, iron, etc.

apple chips

There is no cellar, so we dry the apples and make juice. At first I tried to store it in my grandmother's way - in pillowcases, but this method did not suit us, since there is enough space either in the kitchen in the closet or in the room. Wet steam from the pots constantly rises in the kitchen, and in the room there is a huge aquarium (200 l). Therefore, I tried to store in three-liter jars with lids.
For the experiment, half of the jars were covered with lids, half with a newspaper. Both of them are well preserved.
We opened the last jar at the end of summer (we have late varieties of apples). By the way, my daughters are very fond of nibbling dried apples, especially closer to spring, when beriberi sets in.
The apples were dried in an electric dryer at 500°C for two days (switched off at night). They should become like chips - crispy, otherwise they will not be preserved. Banks wrapped in newspapers to protect from sunlight.

And so on. Harvest and it still serves faithfully. But its effectiveness all the time seemed to me insufficient, or rather, I wanted to make it even more effective. And then the other day I got into the hands of an old refrigerator. And I decided to make a forced-ventilation drying cabinet out of it, which will make the drying and drying process very fast, efficient and safe (in terms of getting rid of flies and wasps that strive to visit processed products). They are known to be intolerant of drafts.

First of all, you should free the refrigerator case from all internal contents. We only need the body itself, usually metal. The only thing that should be left is the seal on the door.

When removing the refrigerator insulation, you should be careful, as it will most likely be glass wool. So that your hands do not itch later, you should wear tight clothes and gloves, preferably disposable polyethylene or rubber, stretched over cloth. A respirator or just a scarf tied over your mouth and nose will not be superfluous.

The inner case - "trough" can be used somehow in the future (for example, as a trolley body), although there are a lot of holes in it. And we are left with only a metal locker.

In the niche where the refrigerator compressor used to be, we cut an ordinary exhaust fan. True, in this case it will work as an injection. Generally speaking, here I am faced with a dilemma. Formally, it is better to use an exhaust fan for drying, which will create a slight vacuum in the drying chamber. The lower the pressure, the faster the drying. But when installing an exhaust fan, the ability to use a fan heater is lost (which dramatically speeds up drying), you would have to install two of them or install a separate air heater.

So for the time being I settled on a 125 mm blower fan (capacity approx. 180 cubic meters of air per hour, 18 watts of power). Maybe later, when the "drying season" begins, I'll try to rearrange it to the hood and compare the results. I specially installed the fan not in the center, so that later I could install either a second fan, or embed a fan heater (for example, from drying an old washing machine).

In the roof of the refrigerator, I cut a hole for a polypropylene pipe and glued it with hot glue. It can be built up by installing a pipe 2 meters high or an aluminum corrugation stretched up to 3 meters. At the top it will be possible to install a Volpert-Grigorovich exhaust deflector and then the draft (and draft) will be achieved on their own, without a fan. This option will be useful for those who have tight electricity in the country.

By the way, I painted the body of the refrigerator (as long as the can was enough) with black matte paint. Now, when the sun appears, the case heats up noticeably, and even with the fan turned on, the air temperature (in the outlet pipe) is 5-8 degrees higher than the ambient temperature (I measured it with an electronic thermometer in a remote sensor).

So that the door of the refrigerator - drying is securely fixed, I attached a regular hook to it. Such as is usually used on the doors of utility rooms or gates. I bent the tip of the hook a little and made a notch on it with a needle file. Now, when closing on the hook, the drying door, as it were, is additionally attracted to the body, being sealed, and fixed in this position. (I did not fool around with different magnetic latches or latches.). By the way, this solution to the problem of closing an old (real) refrigerator can be useful if it lets air through under a worn door seal.

The interior of the dryer is "standard". This is a rack with sliding flat drawers. The bottom of the boxes is mesh, made of fine mesh. Shelves for boxes I made from a narrow board. I had to make a cutout under the protruding edge of the refrigerator. For the efficiency of the drying process, the design should be made such that all air passes exclusively through the bottom. Fastening shelves - directly to the walls of the refrigerator, self-tapping screws. Having marked the wall from the outside, I drilled holes in it, through which I fixed the shelves with self-tapping screws with a head in the form of a pressure washer.

I have to say that I got a little carried away here. It was just necessary to close the recess in the door with a sheet of plywood or plastic. Those. make the door just flat so that when it closes it is flush with the front wall of the refrigerator. I decided to make curly shelves so that the boxes would almost rest against the door and the air would go through them. At the same time, the volume of the drying cabinet increased by the thickness of the door, and the work - by an extra hour or two ... In addition, there were certain difficulties with opening the door - the seal was clinging to the shelves. I had to figuratively file them. But what's done is done. If someone repeats the design, this should be taken into account.

Testing the dryer from the refrigerator completely satisfied me. A bunch of green dill withered for winter storage in less than a day. I even withered some meat (for beer). Meat (beef, boiled-smoked), cut into long strips and grated with salt and pepper, withered to a “rubber” state in just a few hours. It turned out something like biltong or sujuk. So ready for the mushroom - apple drying season!

So if you come across a case from an old refrigerator, spend half a day and you will have a great dryer for mushrooms, apples, berries, herbs and all kinds of medicinal herbs.

If you are a supporter of a healthy diet, and even more so if you grow healthy food yourself, a vegetable and fruit dryer will be your indispensable ally. I want to offer you a variant of a home-made electric cabinet for drying fruits, vegetables, herbs, berries and mushrooms from Ilya Tretnikov.

Materials and tools:
- plywood sheets for the body
- wooden slats
- self-tapping screws
- mosquito net
- drill
- furniture stapler
- heater
- foil
- power cord with plug
- electrical tape

Preparing the main elements

1. Wooden case for dryer
It can be an old bedside table or a wooden case knocked together on your own.

2. Net trays
With their own hands, they are made of a wooden frame and a mosquito net. It is better to connect the frame rails with self-tapping screws, and fasten the mesh with a furniture stapler. So that the grid does not get out of alignment, its edges are wrapped several times. Stretching the mesh on a wooden frame is first in width, and then in length.

3. Rails for placing trays in the dryer
They can be from the same wooden slats 5 * 8 mm in size in profile. Their fastening to the wooden case is carried out using self-tapping screws.

Let's get down to calculations and installation

Step 1. Go without nails

For this device, nails are completely unreliable. In this case, the author of the master class is recommended to use self-tapping screws. So that the self-tapping screw does not damage the integrity of the structure, drill a hole with a smaller diameter from the diameter of the screw leg and only then screw it in.

Step 2. Decide on the design of the future dryer

Ilya Tretnikov suggests considering two types of dryer designs for vegetables and fruits. The first type - up to 13 kg when loading products, square. The second type - the design is complicated and the loading volumes of fresh products are possible up to 40 kg. This option is complemented by a pyramidal installation for fans that provide uniform air circulation. Thanks to the pyramidal shape, the air flow receives a specific direction of movement and reaches the farthest corners.

Step 3. We select fans

According to the recommendations of the author of the master class in the dryer, up to 57 cm deep, the inner working surface up to 39.5 cm high, and 41 cm wide, only one fan is enough to get high-quality products at the exit. Accordingly, a tree with a thickness of 1.7 * 1.7 cm is used, and we get the deco size - 41 * 45 cm.

Basic calculations:

Dryer total depth (57 cm) - pan length (45 cm) = space for air dispersal (12 cm). If you make a dryer for fruits and vegetables with a load of up to 13 kg, this is enough.

When building a dryer for fruits and vegetables, along with a pyramidal structure and dimensions: the width of the inner working surface is 61 cm, the height of the inner working surface is 83 cm, the depth is 42 cm, 2 fans are installed. A baking sheet measuring 41.5 * 60.5 cm.

Basic calculations:

Total dryer height (83 cm) - pan length (60.5 cm) = room to disperse air from the main body to the wall of the attachment (22.5 cm).

Step 4. Thermostat and electricity

In order not to delve deeply into physics, Ilya Tretnikov recommends simply buying a “dutik” heater, as it is popularly called, and immediately getting a set of all the necessary parts.

The main thing is the thermostat built into the fan, which is placed in the middle of the heater body. Its author is a master class and places it inside the working chamber of the future dryer. Using a conventional thermometer, Ilya manually adjusts the thermostat. To do this, it is necessary to rearrange the contacts so that the effect of the thermostat extends only to the heating element. This means that when the maximum temperature is reached, only the coil will automatically turn off, and the fan will continue to operate. When the coil cools, the thermostat will start it again. At this point, you should pay special attention, since the factory assembly of the heater involves turning off the thermostat of both the heating element and the fan. The method created by Ilya is much more economical in terms of electricity consumption.

Step 5 Installing the Coil

Step 6 Install the dryer switch

It is better to distribute the functions of the switch in this way: fan on / heating coil on and fan / off.

Step 7 Dryer Operation Indicators

Ilya uses 2 light bulbs:
- the first is an indicator of the overall operation of the device, that is, it lights up when the “on” position, does not light up when the “off” position
- the second - the indicator of positions "on" / "off" for the heating element.

Step 8 Installing Two Fans in a Pyramid Design

When creating a dryer with a pyramidal design, Tretnikov uses 2 fans, each with one heating coil. But the adjustment of the operation of both heating elements will be performed by only one thermostat. That is, it is very important to obtain as a result the simultaneous opening of the heating elements, since otherwise the drying process will become uneven. To make sure that the temperatures are uniform, it is enough to place several thermometers on different planes throughout the entire cavity of the dryer.