Three graduates from the Indian Institute of Technology, New Delhi, Ankur Kumar, Kanika Prajatat and Pracheer Dutta have developed a machine that can convert the hardy straw of paddy into a fibrous raw material that can be used by the pulp molding factories to prepare disposable cutlery.
In India despite a Supreme Court order, and a government scheme that offers stubble management machines at subsidized rates, farmers continue to burn crop residue after harvest, as they find it cheaper than clearing the crop residue manually or by using machines. The practice is rampant across rice-growing belts as paddy straw is neither a suitable fuel nor can be used as cattle feed. The situation is worse in Punjab and Haryana as the smoke resulting from burning the residue chokes Delhi and envelops the entire northern India with dense toxic smog for weeks.
Paddy straw is rich in silica, which slows down its rate of degradation and hence farmers choose to burn it post harvest to make the land reusable faster. The new machine, created by the trio as the first product of their startup Kriya Lab, uses an environment-friendly chemical that can strip the straw of silica, making it supple and usable. The pulp can be used as raw material for the pulp and paper industry.
For now the machine can convert one ton of paddy straw into 500 kilograms of pulp, which can then be sold at Rs. 45 per kilogram. It holds promise for those who want to start commercially viable ventures as there is a growing demand for ecofriendly cutlery and packaging materials, particularly the ones made from biomass waste. Read more
A team of scientists at the National Chemical Laboratory, Pune, and the Institute of Chemical Technology, Mumbai, has developed a non-toxic technique to recycle plaster of Paris (PoP) waste from hospitals and convert it into useful materials such as ammonium sulphate and calcium bicarbonate.
In hospitals and other medical centers PoP is mainly used for setting broken or fractured bones or for making casts in dentistry. It is a hazardous waste, loaded with bacteria, and affects not only the environment, but also people who collect, segregate, and dispose it.
The new technique treats PoP waste with ammonium bicarbonate solution with a concentration of 20 percent. The solution disintegrates the waste into high value and non-toxic chemicals, ammonium sulphate and calcium bicarbonate in the form of sludge in 24-36 hours at room temperature.
The resultant material ammonium sulphate can be utilized as nitrogen fertilizer, fire-extinguishing powder, and in pharmaceutical, textile, and wood pulp industries, while calcium carbonate can be easily used in steel manufacturing.
The new technique can also be used to disintegrate PoP waste from idols immersed in water bodies.
The study results have been published in the International Journal of Environmental Science and Technology. Read the full report by Vaishali Lavekar.
Scientists at the Indian Institute of Technology (IIT)-Roorkee have fabricated low-cost thin film solar cells by extracting the plant pigments from plums, black currants, and berries.
The team found that the plant pigments are good at absorbing sunlight. According to a study, published in the Journal of Photovoltaics, plant pigments are naturally occurring biodegradable and nontoxic molecules that are extracted using techniques that involve negligible cost to the environment and therefore can provide eco-friendly alternatives to synthetic dyes that are used for thin film solar cells production.
The researchers at IIT-Roorkee extracted the plant pigments using ethanol to create the thin film solar cells. And while the organic thin film solar cells are not yet as efficient as conventional silicon-based solar cells, the team is investigating ways to make them more efficient and cost-effective. Read the full report by Lorraine Chow.
The project, Colored Yarn, has been created to provide technology advantage to the weaver community of India.
The Spinning Wheel
Charkha is one of the oldest known forms of the spinning wheel. It works with a drive wheel being turned by hand, while the yarn is spun off the tip of the spindle. It is a small, portable, hand-cranked wheel that is ideal for spinning cotton and other fine fibers. Mostly, the charkha is used for spinning cotton and the hand spun cloth is called Khadi in the Indian peninsula.
According to the Handloom Census of India 2009-10, India has about 29 lakh handloom workforce working on 23.77 lakh looms across household and non-household handloom units. About seven percent of the 20.91 lakh working household looms continue to use the hand spun yarn, supporting the Khadi programme. The most extensive use has been observed in Tamil Nadu and Karnataka where 30.1 percent and 24.4 percent looms operate with hand spun yarn, respectively.
It is for the community of weavers who provide hand spun yarn for the looms that the young innovators wanted to change the traditional way the charkha works.
The Colored Yarn
Attendra Sharma (20) of the Institute of Hotel Management, Gandhinagar along with Monica J. (21) of PESIT University, Bangalore, and Lavanya Gupta (20) of Dhirubhai Ambani Institute of Information and Communication Technology, Gandhinagar, have developed an innovative prototype of the charkha that allows for the yarn to be colored on the fly.
The trio developed the project as part of the ‘Sensors Across Scale’ track at the 2015 MIT Media Lab India Design Innovation Workshop that was held in Gandhinagar, Gujarat, in January. While the track focused on building new sensor systems working across scales, it also encouraged innovations that “affect human relationships and social problems”.
The 2GB team (two girls and a boy), as they called it, focused on innovating with the spinning wheel not with the sensors but by using basic components such as the box charkha, a pulley, a coloring unit, and a spool.
The team used a briefcase charkha that weighs just about 1.4 kilograms. Here’s how it works:
A tightly rolled tube of cotton, called pooni, is one of the ways to fine and even spinning. Weavers can make poonis from pre-carded cotton by laying a thin layer of cotton on a flat surface and rolling it around a thin stick and compressing it with hands.
For proper tension, the spindle support post must be positioned far enough so that the spindle drive cord holds it vertical. Also, the post base should be angled so that, when the spindle is spinning freely, its pulley rotates midway between the post arms, not touching either one.
For the first time, a leader is added to each spindle to help start the spinning process. The drive wheels turn together smoothly and the tension of the thread gets adjusted by moving the small wheel.
A spinner begins on this apparatus by drawing out the yarn to arm’s length with one hand while turning the big wheel clockwise with the other hand. The trick is to coordinate the speed of the draw with the speed of wheel turning, so that the yarn holds together but not too much twist travels up into the cotton in one’s hand. (Source: http://www.markshep.com/peace/Charkha.html.)
The 2GB team introduced a coloring unit as an attachment to the briefcase charkha. As a spinner spins, the plain thread passes through the unit where color is dropped on the thread through a funnel, producing a clean, dry, dyed hand spun yarn.
“This is a new and unique use of technology on a traditional product. The process of spinning the yarn and then dyeing it in a color of choice is a five-day process. Our prototype not only allows the weavers to color the yarn within a few seconds, but also provides them the freedom to experiment with different colors of their choice for the hand spun fabric, without much dependency on the dyeing process. By making minimal changes in the charkha, we have tried to retain the authenticity of the product and yet modernize it enough to save the art,” said Lavanya and Attendra who conceptualized and engineered the prototype.
The team plans to improve upon the design and function of the coloring unit to create a final product.
To know more about the Colored Yarn prototype, write to firstname.lastname@example.org or email@example.com.
Researchers at the Indian Institute of Technology (IIT-Delhi, Bombay and Madras), along with Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland, and Technology and Action for Rural Development (TARA), have created a Limestone Calcined Clay Cement (LC3) that helps reduce carbon dioxide (CO2) emission by almost 30 percent. The team’s innovative cement production process uses the new blend which substitutes up to half of the carbon intensive materials traditionally used to make cement.
The LC3 is a synergetic hydration of clinker (a dark grey nodular material made by heating ground limestone and clay at a temperature of about 1400-1500 Celsius), calcined clay, and crushed limestone to achieve the performance required from commercial cements, with clinker factors as low as 0.40 (as against 74 percent clinker present in the cement that is currently available in the market).
Reduction in the the quantity of limestone and clay that is used to manufacture cement will eventually also mean a little longer life for the limestone mines. According to a report, a LC3 plant is also likely to cost much less than the investment that is required for a clinker based cement factory.
Currently, more than 30 tons of LC3 has been produced and a building has been constructed near Jhansi in Uttar Pradesh, to check the feasibility of the cement in constructions. Now the cement quality has to pass through standardization committee before it is accepted by the industries. As per a report, the research will not be patented and will rather be available to everyone once it has received due clearances. Read more