Bricks to be made without clay-cement: CUET researchers...

Dhaka, Tuesday   28 September 2021

Bricks to be made without clay-cement: CUET researchers

 Sayeed Chowdhury, CUET

 Published: 06:25 PM, 9 July 2021   Updated: 01:31 PM, 10 July 2021

Bricks can be made in an environmentally friendly manner using geopolymer

Bricks can be made in an environmentally friendly manner using geopolymer

Different types of bricks are manufactured in Bangladesh, especially, clay bricks which are made in the factories located in the countryside. These factories also making bricks made of cement. However, bricks can be made without clay and cement.

A team of researchers from Chittagong University of Engineering and Technology (CUET) has come up with this new method of sustainable brick. The team includes Liverpool John Moores University in the United Kingdom, CUET, Research England, BSRM Bangladesh, Barapukuria coal-fired power plant.

Dr. Monwar Sadiq, a reader at UK’s Liverpool John Moores University, Dr. GM Sadiqul Islam, Professor of Civil Engineering at CUET are the main authors of the study. Besides, SM Shahriar Sifat from CUET and Abdullah Khadim and Haider-al-Hawesh from the UK were the research assistants.

About the study, Prof Dr. GM Sadiqul Islam said the main problem of the bricks of brickkiln is that it absorbs excess (up to 20%) water. As a result, the walls are easily damaged. “But the bricks made in our study absorb a maximum of 7% water,” he also said. 

CUET’s Civil Engineering Professor said research is also underway to keep the price within reach if the production of these bricks can be started commercially. It will soon be possible to market “high-quality bricks with domestic technology”.

“If bricks are made from the waste of coal-fired power plants and steel mills, the hassle of waste removal will also be relieved. So, the solution to waste management will eventually come,” Prof. Dr. GM Sadiqul Islam further said.

In the current world, the production of cement clinker is spreading greenhouse gases, as a result, the environment is under threat. For this, researchers made bricks from different types of industrial waste, such as ‘Fly Ash’. It can be found in coal-fired power plants. It is also possible to use various materials in the steel industry. This requires a geo-polymerization method.

It is possible to make bricks in an environmentally friendly manner “without burning” in the geo-polymerization method by using ‘Fly Ash’ of coal-based power plants and various by-products of the steel industry. In this case, alumina and silica-rich substances melt when they come in contact with alkalis. When sodium silicate (Na2SiO3) is added there, they form a bond in the form of a polymer chain called a “geopolymer”. Such an environmentally friendly method can be used in brick making.

Researchers also said coal-fired power plants – where fly ash is being made – will be the main source of power generation in Bangladesh in the future. For example – Barapukuria Coal Power Plant is producing about 1,09,200 metric tons of fly ash every year – which is becoming a matter of great concern for the fly ash management authorities. 

The situation will get dire in the future when the construction of coal-fired power plants (Matarbari, Bashkhali, Payra and Rampal of 3840 MW) will be completed and its’ production will start. If it continues to grow as it is now, the annual production of fly ash will increase to 10,00,000 metric tons from 2024 onwards. 

If this huge amount of fly ash accumulates, it will create a terrible situation. So, considering the chemical composition of the fly ash, it can be used to make eco-friendly bricks without burning. 

After three years of research, UK’s Liverpool John Moores University and CUET have succeeded in making high-quality bricks using the geopolymer method. 

A discussion meeting was held on the evening of July 5 on this research article. The event was organized by ICE, England (Bangladesh Chapter) and ACI Student Chapter, CUET. 

Azizul Haque, Chief Engineer of Bangladesh Manufacturing, BSRM and Quality chairman Bipin Kumar Sharma, IEB Chattogram Center chairman Prabeer Kumar Sen, and Engineer Nasid Islam, president of ICE, England (Bangladesh Chapter) were present on the occasion.