Unburnt building materials protect natural resources and environment

With great benefits contributing to saving natural resources, especially agricultural land, reducing emissions causing environmental pollution, reducing waste treatment costs of industries, saving fuel and coal, bringing In general, economic efficiency for the whole society, unburnt building materials have been developed in many countries around the world for a long time.

Bricks, tiles and unburnt materials. (Source: Internet).

But in Vietnam, despite the plentiful source of raw materials, the hot and humid tropical climate is needed, unburnt building materials are still " trampling on the spot ," which has the cause of specifying the muscles. policy.

Every year, more than 1,000 hectares of agricultural land are lost

According to Dr. Thai Duy Sam and scientists at the Institute of Building Materials under the Ministry of Construction, forecasting the demand for construction materials in Vietnam to about 41-43 billion bricks (standard norm) by 2020 .

If producing baked clay bricks with this quantity must consume about 57-60 million m3 of clay and 5.3-5.6 million tons of coal. Thus, the loss of agricultural land is extremely large, not to mention the environmental pollution and waste of non-renewable resources.

Not only losing agricultural land, smoke of manual brick kilns has become a concern for many households in rural areas for decades because the emission sources affect human health and cause some crop failures for some cultivated area. Not only that, many brick kiln owners still violently violate land and dike laws to get land for bricks .

In recent years, many businesses and localities have reduced manual brick kilns, invested tunnel kilns to produce bricks. However, despite technological improvements, baked clay bricks still have a lot of limitations when it takes large amounts of land, fuel and toxic gases to emit.

In order to minimize the production and use of baked clay bricks, the Prime Minister issued Decision No. 567 / QD-TTg dated April 28, 2010, approving the Program of developing unburnt building materials by 2020. , with the goal of developing production and use of unburnt building materials to replace baked clay bricks, the rate is from 20-25% in 2015 and 30-40% in 2020.

At the same time, every year, about 15-20 million tons of industrial waste (thermal ash ash, blast furnace slag .) are used to produce unburnt construction materials, saving about 1,000ha of agricultural land and hundreds of hectares. waste land area; proceed to completely eliminate baked clay brick production facilities by manual kilns.

Compared with baked clay bricks, unburnt building materials have many outstanding advantages such as abundant and easy-to-find raw materials, which do not affect farmland, take advantage of industrial waste sources; reduce energy costs, especially reduce emissions, protect the environment.

In addition, it is possible to produce non-baked building materials on a small scale, simple, easy to produce quality products according to the requirements of intensity, size, high precision. Another outstanding advantage is some light unburnt building materials, good insulation, good sound insulation, contributing to energy saving in hot and humid weather conditions in Vietnam.

For example, the common two-hole brick wall construction with a unburnt building material is a hollow block of SHB2-150 with a size of 390x150x190mm, showing a 60% mortar block, a construction time of 1m2 60% discount, the price of standard-sized bricks is reduced by 25% .

Many mechanisms encourage the development of unburnt building materials

Currently, the country has about 900 production facilities of unburnt building materials, with a total capacity of 1,529 million tablets (standard regulations) / year. Including about 350 production facilities with very small capacity (less than 1 million tablets / year), the total capacity of unburnt bricks is about 1,700 million bricks / year.

According to the general assessment, production of unburnt building materials is still mainly in a very small scale, fragmented, spontaneous, the proportion of medium and large production facilities is relatively low (28%). Vietnam does not have a number of unburnt bricks such as silicate bricks, autoclaved aerated concrete bricks . which are relatively popular in many countries around the world.

According to Dr. Tran Van Huynh, Chairman of Vietnam Building Materials Association, with higher economic efficiency, the replacement of baked clay bricks with unburnt building materials will be a development trend. However, the current problem is the policy mechanism and habits of consumers.

Currently, standards related to design requirements, construction guidelines and acceptance are not specified for each object of unburnt building materials. Therefore, the design consultant has not bravely designed to bring non-baked building materials into universal construction projects.

Mr. Le Van Toi, Director of Construction Materials Department under the Ministry of Construction said that since 2001, China has issued a list of 170 cities prohibiting the use of baked clay bricks for construction; regulations to collect an additional fee for architecture of houses using baked clay bricks.

Meanwhile, in Thailand, there is no need to enact policies to encourage unburnt building materials, but the State strictly controls land use. Therefore, baked materials cost more than many unburnt building materials. Regulating market factors make the unburnt building materials industry in Thailand develop as light concrete has been 10 years ago.

According to the unburnt building materials development program by 2020, approved by the Prime Minister, from 2011, high-rise buildings (from 9 floors or more) must use at least 30% of construction materials. light burning (volume of not more than 1,000kg / m3) of total construction materials; Encouraging construction works using other unburnt building materials with a porosity greater than 30% and light unburnt building materials.

In order to encourage all economic sectors to invest in the production and trading of unburnt building materials, the State has promulgated preferential policies on import tax and enterprise income tax; projects of manufacturing equipment for manufacturing non-baked building materials and producing cement bricks - aggregates with the capacity of 7 million standard bricks per year or more are entitled to the same incentives as for projects under the program key mechanical .

The Government also assigned the Ministry of Construction to assume the prime responsibility and coordinate with the concerned ministries and branches in implementing scientific and technological solutions to develop production and use unburnt construction materials; make a list of equipment and materials for production of unburnt construction materials exempted from import tax; build a roadmap and urge the elimination of manual brick kilns by regions and regions; organizing information and propaganda on production, using unburnt building materials.