Lime is the most popular material for wall treatment. It has disinfecting properties and is absolutely not affected by mold and various fungi. In addition, lime is also very cheap. Its price makes this material indispensable for decoration of public places, especially in small towns and villages.
The purpose of this article is to tell readers how to extinguish lime correctly and why it should be done.
Lime itself is a mixture of substances that are a product of calcination of limestone rocks. Most often on the shelves of our stores you can find quicklime, or lump, there is also fluff lime.
Lime wall treatment is the most hygienic way to finish. The fact is that this material neutralizes any microorganisms that fall on it. In addition, lime has excellent strength and moisture resistance.
This method of decoration has its drawbacks. If the person performing the work does not know how to dissolve the lime, and does it wrong, then stains, bubbles and streaks will surely remain on the treated surface. Too thin a solution will not give a beautiful even color, but an excessively thick one will fall badly on the wall, and after a while it will rise and fall off.
Like all other building materials, lime is subject to standardization. The quality of the material depends on the percentage of calcium and magnesium oxides in it. In lime of the first grade, the total amount of these substances should be at least 90%. The lower the grade, the less oxide. In lime of the lowest, fourth grade, the total amount of magnesium and calcium oxides does not exceed 60%.
The price of quicklime and quicklime in the market is significantly different. Quicklime can cost about 3-5 thousand rubles per ton. Slaked lime is much more expensive . Its price can reach 10 thousand rubles per ton and even more.
Slaked lime “fluff” is used very widely in the household. In some cases, it is used even when cooking. But still, most often it is used for such purposes:
- when whitewashing the ceiling and walls;
- to protect wooden structures from fire or rot;
- in the production of silicate concrete;
- when laying the inside of stoves and fireplaces;
- in the manufacture of the connecting solution.
It is no less widely used in agriculture. Everyone knows that one of the most necessary materials in the country and in the garden is slaked lime. Its price is so low that the material can literally be buried in the ground, using for fertilizing and liming the soil.
In agriculture, lime is used:
- for the production of lime fertilizers;
- in the preparation of bleach, necessary for the treatment of trees and shrubs from pests;
- for the processing of beds from pests and the control of diseases of certain plants;
- when tanning animal skin;
- for the preparation of calcium compounds used for wastewater treatment;
- for the preparation of E 526 - additives used in the food industry.
In almost all areas of business, only processed material is used, but before we talk about how to extinguish lime, let's look at its classification. The main separation of lime is done depending on the rate of its slaking:
- slow extinguishing - the whole process takes more than half an hour;
- medium extinguishing - extinguishing takes 15–25 minutes;
- quick-extinguishing - everything happens very quickly, in 5-10 minutes.
The second classification takes into account the characteristics of hardening:
- air - such lime is used to increase the rate of hardening of mortars in dry conditions, in air;
- hydraulic - used for solutions that must have special strength; used in works carried out in water: construction of port foundations, bridge supports and so on; happens weakly and strongly hydraulic.
The third and final type of lime classification is by fractions. Depending on the size of the pieces, it can be:
Principle of work and safety measures
Correctly extinguishing lime at home is not difficult. This will not require much time, no special skills, or special equipment. Nevertheless, the process must be properly prepared.
When extinguishing lime, an exothermic reaction occurs, that is, a large amount of heat is released. And in order to avoid injuries, before extinguishing lime, you need to prepare:
- safety glasses and gloves;
- clothes that are resistant to alkali, best canvas jumpsuit;
- a respirator that can protect the respiratory system from dust, gas and lime particles.
You will also need a blanking tank, water and a long stick for stirring.
How to extinguish lime for construction purposes
So, we begin the process of converting quicklime into slaked lime, observing, of course, all the precautions.
Before dissolving lime, put on tight protective clothing, glasses, a respirator and gloves.
- Pour lime into the prepared container. It is best to use metal dishes without signs of rust for these purposes. A plastic barrel or bucket will not work. The fact is that during quenching, the mixture heats up to 150–180 ° C, and the plastic can melt.
- Carefully fill the mixture with cold water at the rate of one and one (if you need to get a "fluff"). If you need to make lime dough, then for 1 kg of lime you need to take half a liter of water.
- Water needs to be added in small portions, especially if your lime is a large fraction. If you pour out all the liquid at once, there is a chance that the big lumps will “coke” and the process will drag on for a long time.
- Thoroughly and very carefully mix the resulting mixture. We do this every time we notice a decrease in steam above the surface of the tank.
- After the vaping has completely ceased, close the container with a lid and leave to insist for 24–36 hours. After this, the mixture should be carefully mixed again and left to infuse in a dark, cool place for at least 14 days (for masonry), and preferably for a month. Only after that the lime will get its properties and it will only be necessary to strain through gauze.
Attention! In no case should you bend too low over the tank - fumes emitted during the reaction can cause severe chemical burns.
Lime for whitewashing and spraying trees and bushes
As we have already said, this wonderful material is used not only in construction, but also for garden work. So let's talk about how to extinguish lime for trees.
To make a solution for whitewashing trees, you need to take 1 kg of lime powder and 2-3 liters of water. Observing all precautions, extinguish lime and leave the solution for 48 hours to infuse. If you are going to use a spray or spray gun to whitewash the trees, then the resulting mixture must be carefully filtered. If you will whiten the trees with a brush, then filtering the solution is optional.
In order to keep the mixture better on the trunk and branches, you can add a little PVA glue, milk or a special “stick” to the solution, which is sold in stores for gardeners. If you decide to process trees and shrubs in order to rid them of parasites that live under the bark, then, in addition to all of the above, do not forget to add copper sulfate to the solution. The resulting mixture will acquire a bluish tint, but there is no way to survive any living creatures in the cortex.
How to breed already slaked lime
You already know how to extinguish natural lime, so to speak. Now let's talk about how to properly prepare a solution of the desired concentration from an already extinguished lime. There are some nuances:
- A large amount of water cannot be poured into the lime dough immediately; it is best to act gradually. The maximum portion of water that can be poured simultaneously is 1 liter per 2 kg of “fluff”.
- Dilute the solution with cold water only.
- The diluted mixture cannot be used immediately. Leave it for another 12-24 hours, all components must "make friends" with each other.
If you want to use the mixture to whitewash the ceiling or walls, use a little trick. Prepare a saline solution (2 kg of salt per 1 liter of water) and mix it with lime, achieving the desired density. Leave the resulting mixture for another 24 hours, then strain everything thoroughly through a fine sieve or gauze.
Such an additive will fix the mixture, lime whitewash will stay longer on the wall, leaving no residue on hands or clothing when touched.
Lime is a wonderful, cheap and easy-to-use material, no one has come up with an equivalent replacement for it yet. Now you know exactly how to extinguish lime, and without outside help and unnecessary costs you can prepare whitewash for bushes and trees, make a mixture for masonry or plaster.