• Elucidating technical properties and the ability of the use of low quality dolomite (loose, weathered) in Ha Nam and Ninh Binh regions to product non-calcined materials.
• The project proposed technological process for production of non-calcined bricks from dolomite rocks in Ha Nam and Ninh Binh regions.

Theoretical results:

• 2 Articles on specialized scientific journal.

• Research results in material component and technical properties of weathering dolomite in Ha Nam and Ninh Binh show that:
  • Mineral component are mainly dolomite (68 – 98%), calcite (3-25%) and some clay minerals. Their chemical composition analyzed by XRF composed of MgO 12.90 – 20.08%, CaO 30.82-39.16%.
  • The reactivity index of dolomite was 44.59-67.32mgCaO/g.dolomite. Activated dolomite in Ha Nam and Ninh Binh are a useful material resource for the production of non-calcined bricks which are the type of “Dolomite+Lime”.

Applied results:

• Using the main mineral resource which was dolomite in Ha Nam and Ninh Binh and applying the optimal mixing ratio: Dolomite(75%):Lime(10%):Sand (15%), the project made the trial for production of non-calcined bricks and the test results achieved the building standard with compressive strength: 59kG/cm² (TCVN 6477:2011) or 98kG/cm² (TCVN2118: 1994), bending strength: 22kG/cm², density: 1.63-1.89g/cm³, water absoption: 13-14%.

• The project proposed a feasible technological process for production of non-calcined bricks by using activated dolomite rocks.

The research results of the project contributed to establish of an activated material source which was useful for the production of non-calcined construction materials. The project also proposed an appropriate technology progress for production of non-calcined bricks using these materials.

Scientific papers in referred journals (list):

• Dolomite and its potential use in non-fired construction material production. Journal of Geology, Series A. No.350, 3-4/2015, pp 44-49.
• Reactivity of dolomite rocks in Ha Nam region and technical properties of non-calcined brick made from these raw materials. Journal of natural resources and environment, No 12-(218), pp 34-36.

Technological products (describe in details: technical characteristics, place): 80 samples of non-calcined bricks produced from dolomite in the research region with the size (200x100x55mm), achieved the standard of a non-calcined brick (TCVN6477:2011 or TCVN 2118:1994), compressive strength of 59kG/cm2, and tensile strength of 22kG/cm2. These samples are stored in Institute of Geological Sciences.

It is necessary to have programs introducing technology and making test production in places where material source of dolomite are plenty such as Ha Nam, Ninh Binh…

Manufacturing calcined bricks based on traditional technology has caused environmental pollution. Therefore, for sustainable development, reasonable use of natural resource and meeting demands on construction materials, it is necessary to start a test program on the manufacture of non-calcined material using dolomite. From this test program, there will be a suitable and perfect manufacture technology for producing non-calcined materials in this region. As the result, the development of scientific techniques will be applied to serve our lives and the economic efficiency of mineral resources will increase strongly.