New types of environmentally friendly heat-insulating materials
Today, great attention in the construction of houses is given to their energy efficiency, the ability to keep the temperature comfortable for a person inside. The meter-long brick walls are being replaced by frame technologies using heat-insulating materials.
But most of them are either fully synthetic or manufactured using chemicals. However, scientists are constantly working to find environmentally friendly, completely natural thermal insulation material with good performance properties.
Let's talk about the latest developments in this area.
The content of the article
Foam wood
This unique material was received by German scientists from the Fraunhofer Institute. The thermal insulation foam created by them consists of specially treated wood, and therefore is completely natural. It is harmless to both humans and the environment, even if disposed of.
For reference. Used materials can be used as firewood for a stove or fireplace.
Preparation method
Research lasted several years and began with the use of wood bark as a raw material. It seems that the experiment was not particularly successful.
The described material was obtained in the following way:
- The wood is first crushed very much. Judging by the description, it turns into a gel-like viscous substance due to the presence of natural resin - lignin in natural raw materials;
For reference. What you see in the photo is just small filings. While there are no images on the network illustrating the process of making wood foam, so you have to turn on your imagination.
- Then, natural substances accelerating hardening are added to the resulting mass;
- The next stage is the injection of a special gas into the substance to form bubbles and impart a foamy structure;
- The finished solution is given the selected form and dried.
While the inventors do not experiment with forms, they only produce rigid sheets and thin elastic mats to test the material in practice. But there is evidence that designers have already appreciated the idea and are trying to make designer furniture from foam wood.
Advantages over other heaters
The new material has undergone many laboratory studies and analyzes. Without going into technical details, we will talk about its advantages over such popular heaters as polystyrene foam and mineral wool.
| Compare material | Wood Foam Benefits |
 Expanded polystyrene |
|
 Mineral wool |
|
The advantages of wood foam are also listed.
It:
- High rates of heat saving;
- Resistance to mechanical stress;
- The rigid and elastic structure of the material makes it easy to apply it to warm vertical surfaces;
- Good moisture resistance (higher than that of ordinary wood and mineral wool);
- Long term of operation.
Unfortunately, information about the bacteriological stability of the material and its fire safety could not be found.Most likely, scientists are still working on these parameters. But even in this form, wood foam deserves attention, and has great potential for implementation in industrial production.
For reference. In 2015, she received the GreenTec Award in the Construction and Life category.
Foam Wood Raw Materials
Having decided on the technology for the production of foam from wood, scientists conduct research with different types of wood, trying to find the most effective. And they solve the problem of introducing the process into industrial production.
The fact is that it is too expensive and wasteful to use commercial wood for the manufacture of such a heater. It is necessary to find cheaper and affordable raw materials, the use of which will not harm the ecology of the planet.
Most likely, it will be the waste of woodworking enterprises, processed and substandard wood, various wooden garbage.
I would like to hope that not much time is left before mass production, and new technologies will come to our country rich in natural resources. Scientists have no doubt that foamed wood will quickly conquer the market due to its environmental friendliness, safety and effectiveness.
Seaweed insulation NeptuTherm
On the sandy beaches of the Mediterranean, tourists often see unusual red balls the size of a chicken egg. These are dead dry algae Posidonia Oceanica rolled up by the sea, in vernacular - balls of Neptune.
Until recently, beach cleaners just dumped them in the trash. While scientists from the same Fraunhofer Institute did not pay attention to this constantly renewable natural material, and decided not to use it as a heat-insulating material.
Manufacturing technology
In the form in which these algae lie on the shore, they were unsuitable for the implementation of the intended goal, since there is too much sand and sea salt inside them. And what can be insulated with balls?
Researchers have found a way to transform them into another form, more convenient for use as thermal insulation. To do this, it was necessary to separate the algae fibers from each other and free them from unnecessary impurities.
The technology, in principle, turned out to be very simple and low-cost both in time and in the amount of energy used.
- The collected balls of Posidonia Oceanica are first dried at a certain temperature;
- After which they are poured into a specially designed combine, in which intensive shaking occurs, in which the sand is separated from the algae;
- Raw materials purified in this way are sent “under the knife”. It is crushed by a cutting machine into fibers one and a half to two centimeters long;
- The finished material is packed in plastic bags and transported to the place of sale or immediately to the construction site. Or it is pressed, stitched with strong threads and rolled up like mineral wool.
Material Features
Here are qualities such as fire resistance and resistance to decay and the spread of mold, scientists in this case noted especially. Unlike foamed wood.
- The high content of algae in the sea salt prevents their decay, and iodine and other chemical elements scare away the material of rodents and harmful insects.
- Another advantage is the ability to absorb water vapor without loss of thermal insulation properties. And the ability is also easy to release it back without accumulating in itself.
- In terms of heat capacity, loose insulation from algae is 20% higher than wood insulation. This indicator is 2.5 J / (kg · K).
- This is a very cheap raw material, which is a constantly renewable natural resource that does not require human participation.
- Finally, no synthetic additives are used in the manufacture of NeptuTherm. This is a completely natural material that can be used when warming rooms for children, allergy sufferers and people sensitive to chemicals.
For reference. NeptuTherm also won a very prestigious award in the NeptuTherm competition in the Green Building category.
So far, this material is produced only in Germany by a company also called NeptuTherm. Neptune balls are delivered to this country from Albania and Tunisia, where they are collected manually on the Mediterranean coast.
How effective and affordable these heaters will be, time will tell. But even the fact that more and more natural ones appear among synthetic materials is very pleasing and encouraging.
