From Waste Management to Waste Valorisation
Updated: Jul 7, 2021
The idea of climate change was conceived by scientists as early as 19th century after the industrial revolution. Continuous efforts to determine the effects of CO2 emissions established facts and proved the concept. There was then a widespread consensus to develop efficacious, economical and ecological technologies. We are the first generation to feel the effect of climate change and the last generation who can do something about it.” said Barack Obama, Former US President in 2015 when the world accepted the idea of climate change and the process for climate resilience started. Every effectual mission starts with a science backed thought that needs to be nurtured over a significant time period. Transposing to a greener and sustainable planet is a challenging mission that humanity has initiated. Earth’s temperature has risen by 0.08° C per decade since 1880, and the rate of warming over the past 40 years has doubled to 0.18° C per decade since 1981. In India, mean annual temperature has increased around 0.59°C between 1901-2007. The warming trend has accelerated over the period of 1971-2007, with warming strongest in the winter and post-monsoon seasons. The data only justifies the necessity of monumental efforts to stop or reverse climate change. It is imperative to mend ways from a linear economy to a circular one.
Linear economy is characterized by usage of fossil resources, and a consumeristic design and production technique. This way of life typically leads to thrashing of end-of-life materials into a landfill. As a $3 trillion economy, with an increasing aspiration level of the young demographic, the problem of shifting to a circular economy gets intricate in India. The advent of economical greener technologies has been slower than the climate change itself; and in spite of willingness to adopt the cleaner technology, it compels the industry to utilize the economical but a polluting one. The consequence of this is more than 75% of waste ending up in a landfill. This waste consists of more than 45% organics that start decomposing and lead to fires due to the heat generated by decomposition. Nearly 20% of methane gas emissions in India are caused by landfills. While there are methodical efforts to shift to more energy dense fuels and efficient petroleum utilization in India, the inconspicuous waste management problem should not be ignored as it will take a center stage in climate change mitigation efforts sooner than later.
The waste management has been a laggard act in India as the waste is not segregated at point of generation and there is no profitable technology available to segregate and recycle the components in such mixed waste. There have been concerted efforts in urban areas through government sponsored programs to create awareness among the public to segregate and dispose of the waste in a systematic manner. However, these efforts are yet to fructify. The collection and disposal of waste in landfill still remains a more profitable operation than recycling the waste. The mixed waste from urban areas in India that reaches landfill consists of 45% organics, 17% paper-based materials, 12% plastics, 5% glass and 5% metal broadly. The calorific value of this mixed waste is around 10 MJ/kg. The lower calorific value of mixed waste compared to petroleum (45MJ/kg) along with huge emissions during combustion makes it uncompetitive as a fuel candidate. From the perspective of recycling back into materials, only the plastic component in the mixed waste has an enticing potential but a segregation operation to recover value from only 12% component is uneconomical. We therefore need to rethink the waste management operation to make it climate resilient and profitable.
In India around 1100 million metric tons of waste is generated annually. 40% of the total waste generation happens in industries at the point of first utilization of resources while 55% (mostly inert waste) comes from construction and demolition operations. The domestic waste at the end of consumer usage of the product contributes to only 5% of the waste. A systems approach must be used for managing the waste in India such that the waste stream in each industrial operation is identified and processed at the point of generation. The food waste for example consists of starch that can be converted to value added chemicals. The agricultural residues can be converted to various renewable materials and chemicals that do not have petroleum analogues. Carbon dioxide from coal combustion can be converted to chemicals and mining waste can be subjected to bioremediation. The technologies are available to deal with homogeneous waste streams. We need to focus on creating wealth from industrial homogeneous streams that will ultimately lead to strategies for heterogeneous end of product life waste streams. We need to migrate from waste management strategies to waste valorisation strategies because waste only indicates failure of human imagination!
Dr. Saurabh C Patankar and
Mr. Kunal K Godambe
For more information, https://www.greenshiftnrg.com/