With building stock set to increase manifold in India over the next few years, the conversation has moved to how we can continue to progress, but in a sustainable way. Constructing more buildings is essential, especially given the kind of urban development the country is seeing – after all everyone needs a roof to sleep and work under.
But there are fundamental changes that need take place in the building industry if we don’t, at the same time, want to be victims of the very development we encourage.
It is high time that all stakeholders of the building industry think about the practical solutions that are possible given this scenario. And one such practical solution that can result in significant benefits is using natural gas for brick firing.
While this might seem like an innovative move, you might be surprised to learn that Europe has been using natural gas for brick firing for as far back as 1960s. Seeing its many benefits, using natural gas for brick firing was mainstreamed in Europe as early as 1970s and 80s. So much so that by 1990, almost 80% of the fuel used in European brick making was contributed by natural gas.
It might be stating the obvious that natural gas is cleaner fuel. This means it will not pollute the environment as much, given it generates lesser particulate matter and results in less CO2 emissions. That might seem like enough reason for the brick industry to shift to natural gas, but there are more benefits. This process improves the overall quality of bricks and is safer for the health and wellbeing of the employees who work in the kiln.
But let’s be honest. Market reality is a consideration for any industry, as it is for the brick industry. Granted that using natural gas to fire bricks produces less pollutants, but what about the feasibility aspects? Here is where we can borrow significant lessons from the experiences of the European brick industry.
We can see from the graph above that the European brick industry adapted to natural gas gradually. This happened as natural gas availability and pipeline network expanded. Additionally, technologies such as better designed driers and kilns; the use of high-speed burners; and automated control of drying and firing regimes continues to make the process and end product economically viable.
However, the fact of the matter is that even in Europe the shift to kilns using natural gas took over 30 years. So is it really possible in India?
The good news is that this change has already started taking place in India, albeit slowly. One encouraging example is from Wienerberger India, who have converted their factory at Kunigal, Karnataka to natural gas firing. The bricks (hollow blocks) being made in this factory are found to be 60% lighter than conventional walling material (solid bricks), which converts to significant savings on structural cost due to reduction in dead load. This is in addition to the fact that lighter bricks allow for faster construction and ease of handling. Overall, the natural gas fired bricks being made in the factory are consistent and of higher quality.
Additionally, the Government of Punjab recently announced that it would explore the possibility of shifting brick kilns from coal to natural gas. While many kilns in the state had already shifted to the more energy efficient high draught zigzag kiln, government officials note that these kilns can further shift to natural gas without much change in their design. CNG is already widely available in Punjab.
So yes, brick firing with natural gas is possible in India but it does come with a few caveats. In fact, even our neighbour, Bangladesh, has been using natural gas to fire bricks for several decades now and has operational natural gas fired Hoffmann kilns.
A Natural Gas Fired Hoffmann Kiln in Bangladesh
While in Europe, the brick industry is an organised industry and the brick kilns employ tunnel kiln technology, in India the brick industry is unorganised, with numerous small enterprises and mostly using zig-zag, FCBTK and clamp kiln technologies. Work is needed to develop cost effective technology solutions to convert existing kilns to natural gas firing. The dispersed nature of the industry will surely pose a challenge for supplying natural gas to brick kilns. Shifting to this newer process requires investment in both natural gas infrastructure and for upgrading the kiln. This means financial investment from kiln owners and brick makers being trained to use the new technology.
This might seem like a speed bump at this point in time but we only need to look at the European experience to know that the investment is worth it for all stakeholders involved.