Generating Value from Waste

My journey with Protoprint, a social enterprise in India that converts waste plastic into 3D printer filament.


Waste pickers belong to a socially and economically marginalized community in India. Many make their living by sorting through garbage and separating plastics and metals from organic waste. They sell what they collect to local scrap dealers and form the base of the recycling pyramid. Unfortunately, they earn very little for their important work, often less than $2/day. That’s the problem.


During my sophomore year of college, on a trip back home to India, I was introduced to an advocate for the waste-picker community in the city of Pune. We ended up talking extensively about urban waste-management in Indian cities and she encouraged me to visit a local garbage dump to learn more about how the system functioned.

A few weeks later, I visited the dump with my parents. The first thing that struck us was the sheer magnitude of the operation. Large black crows sat atop mountains of unsegregated waste, cawing harshly as a group of pigs wound their way across the field. The landscape in front of us was in stark contrast to the developed urban city it resided within. Strong odors overwhelmed the senses as we navigated through piles of plastic bags, leaky batteries, organic waste and animal carcasses.

Hidden behind one such pile were a group of waste-pickers who were collecting plastic bottles from the garbage and throwing them into large white sacks. They politely listened to our questions and gave us detailed answers about how the scrap system in the area functioned. After walking around a little we were eventually asked to leave by a police officer. We departed with a lot on our minds, most notably that the waste-pickers were not adequately compensated or appreciated for the important work that they did.

The problem, as we saw it, was that while the waste-pickers played an important role in segregating and transporting the plastic, they captured a very small portion of the recycled plastics value chain. A more thorough look at how the plastic was processed made it clear that the lion’s share of the value was added higher up in the hierarchy. When we followed the chain, it looked something like this: First, the waste-pickers sold the plastic they collected to middlemen scrap dealers for ₹18 (27¢) per kg. After the plastic was cleaned and shredded at a scrap lot, the flakes were sold to larger dealers for ₹48 (72¢) per kg. The flakes were then heated and extruded into plastic pellets which sold for ₹75 ($1.14) to recycling companies and injection molders that manufactured different products from the plastic feed-stock. The end result was that, while the waste-pickers formed the base of the pyramid, most of the profits accrued at the top.

My parents and I began talking informally about whether we could use a technology solution to add value at the waste-picker level. In particular, we were interested in looking into a low-cost, distributed production model that could be managed and operated by the waste-pickers themselves. None of us had the requisite background in plastics or waste-management, but we googled our way through a lot of the basics and reached out to experts when necessary. We began by looking at other inclusive production models and studied them to check if they’d be a good fit for the dump. Our improvised analysis (scribbled with a faint red marker on an old white board) inadvertently resembled a Pugh chart as we considered a diverse set of options (injection molding, pelleting, etc.). A few weeks into this process, we stumbled onto 3D printing. At the time, my father was interested in building a printer and it struck us that converting the waste to 3D printer filament might be a way to add substantial value to the plastic.

The feed-stock for an FDM 3D printer consists of a simple plastic filament and preliminary research suggested that it required a relatively standard process to manufacture it. Our thinking was that if the waste-pickers could produce the filament at the dump-site they would capture a significant amount of the value-add locally.

The group of waste-pickers at the garbage dump had told us they earned roughly 27¢ per kilogram by selling the plastic to local scrap dealers. A kilogram of 3D printer filament retailed around $30. That was several times more value for a relatively simple product.

At this point, the project in its entirety was a few abstract ideas on a beat up whiteboard. We realized we would need an experienced partner on the ground if we wanted to follow thorough on our idea so we reached out to the senior management at SWaCH, India’s first wholly owned cooperative of self-employed waste-pickers. A few months after pitching the idea and outlining our strategy, we formalized a partnership with the cooperative and began planning a pilot production facility at an old garbage dump in Pune.

We started by conducting a thorough survey of the various types of plastics that the waste-pickers collected and sold. Based on the data, we decided to focus on High Density Polyethylene (HDPE) as our plastic of choice. In addition to there being a significant amount of HDPE in the area, we also chose it because it was usually easy to identify (from the Number 2 Stamp). Other plastics (like polypropylene), while abundant, were not as well marked and thus harder to accurately sort and process. There were some indications that HDPE filament would warp on being printed, but the experts we consulted suggested that we would be able to control the issue mechanically. By late 2012, in collaboration with a retired army engineer, we had assembled a custom built 3D printer around a solid steel frame with an all-metal hot-end capable of extruding at over 350 degrees centigrade.

Our first shredding machine was manually powered and took over 20 minutes to shred a single bottle. Following our initial tests, we quickly decided to build a motorized version.

Around the same time, we prototyped our first processing machine. Months of design and development culminated in a terribly inefficient, hand-powered shredder. As we took a step back and analysed our work, it became clear that we needed an experienced hardware partner to help us build the machinery.

Fortunately, a local manufacturing firm named Raj Engineering agreed to custom build a machine to process the plastic. We were also assisted by a university group in Seattle that helped us with the early machinery. After months of iterating on our designs, we successfully extruded filament from waste HDPE in mid-2013. It wasn’t much, but we were excited.

Having demonstrated that the model could potentially work, I focused my senior year on raising funds for the project. MIT has a lot of great resources for social projects, but I had failed miserably when I tried to raise funding a year earlier. I hoped that the extra year of progress would validate the model and convey our commitment towards the project. Most of our machines were still hack jobs (our extruder was powered by a drill and heated using a nichrome coil) but we had made significant headway towards proving the concept and we leveraged that progress during pitch sessions. My girlfriend at the time helped with the various business plans and grant proposals. Together, we pitched at multiple funding events but continued to face rejection from the vast majority.

Then slowly, our luck changed. We began to make a financial case for our ‘Fair Trade Filament’ model and, by the spring of 2014, we had won the MIT Legatum fellowship and received grants from the IDEAS competition and the MIT Development Lab. I was also fortunate to secure an Echoing Green fellowship that provided us with funding and support for a two year period. In total, we raised $130,000 in predominantly grant funding and made some valuable contacts in the 3D printing space. We finally had the capital to implement our idea.

Setting up the shed during the monsoons. The site was filled with uncleared garbage and we were frequently visited by mongooses and snakes.

I graduated college in 2014 and moved to Pune by July that year. It was a hard decision because it meant getting into a long-distance relationship with my girlfriend, but I was excited about Protoprint and was rearing to go.

We formalized our partnership with SWaCH and received permission from the Pune Municipal Corporation to set up a pilot at the local garbage dump where we constructed a small shed and set up our machines. By that point, we were into the third design iteration for most of our equipment but continued to face issues with quality control.

The first 6 months were plagued with delays. It took us over a month and a half for the government to approve an electricity meter and then another two months to install a reliable water supply. We had a strict no bribe policy and that led to further delays as we tried to negotiate with local officials.

We received an endorsement letter from the Pune Municipal Commissioner but a local politician didn’t want us setting up the shed and that led to additional delays. A large amount of time was spent waiting outside government offices obtaining different clearances. There were also times when our material was stolen from the shed and our equipment damaged. On one particularly humorous occasion, we decided to place a metal cage outside the shed to store our plastic, arguing that it was too difficult to break into. When I visited the shed the next day, the metal enclosure was conspicuously missing. We didn’t foresee that a group of people could simply carry the entire (8 ft x 4 ft x 2 ft) cage away!

Another hurdle was integrating into the community. I was born and raised in Pune but was clearly an outsider to the waste-pickers. Having SWaCH’s support was a huge benefit, but it still took months of working with the community and interacting with them individually before I felt confident that they wanted to work with us. As we expanded our team, we trained one member of the co-operative to operate the machines and fifteen others to source the plastic. As the months passed, I began feeling more connected to the community and started having longer, more meaningful discussions with our waste-picker partners.

An early member of the team processing HDPE plastic at the shed

That said, after nine months on the ground we were still not producing high quality filament. We had iterated and improved our machines considerably but continued to face issues with diameter consistency and quality control. After reviewing our process, we decided to add three more components to our production line to improve quality. In collaboration with our engineering partners, we built a new water cooled, machine pulled extrusion assembly and added a dedicated dryer to remove excess moisture from the flakes. We also had a few interns develop a diameter sizer to ensure filament consistency. It was an expensive overhaul of our shed but, by mid-2015, we had started producing consumer grade HDPE filament.

Around that time, my girlfriend (of 4 years) and I broke up. It was an excruciating experience to go through while on opposite ends of the globe. As I progressed through what I’m told are the various stages of coping, it was difficult to stay motivated and those next few months were the hardest of the entire journey.

Soon after that, we began to realize that the chemical warping issues with HDPE were more significant than we had earlier anticipated. While our filament was printable, the final output left much to be desired. After consulting with scientists from the National Chemical Labs (NCL), it became clear that the issue was due to uneven internal stresses that resulted from the crystallization of HDPE as it cooled. The problem was intrinsic to the chemical structure of HDPE and would have to be tackled with a chemical solution.

Over the next few months, we spoke extensively with the polymer scientists at NCL and described our vision with Protoprint. The faculty, consisting of some of the most sought after scientists in the world, kindly volunteered some of their time (and resources) to explore if we could develop a chemical additive to prevent the warping. As we applied for government grants to fund the research, we continued to make incremental progress with the print quality by bootstrapping our resources and looking into mechanical fixes for the issue.

The next few months moved slowly. We didn’t made a lot of progress on the print quality and it was becoming clear that that was our primary constraint. We took a number of measures to reduce our burn rate and I moved back in with my parents and stopped drawing a salary.

By the fall of 2015, we had 40 waste-pickers sourcing the HDPE plastic and two members of the co-operative working full time at the production site. As our network grew, local scrap dealers began to take notice of our operations. Because of the asymmetric value chain, it was strongly in the dealers financial interest to maintain depressed waste-picker incomes and they viewed our project as an unwelcome change to the status quo. That September, a group of waste-pickers told us they had been threatened to ensure they didn’t continue working on the project. The following weeks consisted of tense and uncomfortable conversations. Eventually, we resolved the disagreement and returned to our original collection rates, although this was largely because we were too small of an operation to pose a significant financial threat to the scrap dealers.

In early 2016 we received word that our grant application in collaboration with NCL had been approved by the government. The funds would allow us to buy customized printer hardware and hire a chemical engineer to work at NCL full time. The grant would fully fund the development of the additive and was welcome news.

Simultaneously though, things were slowing down at the shed. Our waste-picker partners were wondering when we would start producing filament at scale and if it made sense to continue spending our resources on research and development. We made a decision to temporarily halt filament production at the garbage dump until we had the additive ready. Over the next few weeks we leveled with our waste-picker team about how things were going slower than expected and that a solution might not be immediately forthcoming. We also spoke extensively with the SWaCH management about alternate methods we could explore to add value to the waste plastic. Together, we began looking into injection molding, flaking and pelleting options to up-cycle the waste.

Over the past 6 months we’ve made incremental progress on the filament and had some success dealing with the warping issue. While the additives we’ve tested have limited the warping it is clear that we are not quite there yet. We’ve also been impacted by internal politics within the local government and our permission letters have been delayed. That said, with the grant in place and the right partners to work with, we’re chugging along slowly and are only a couple of key breakthroughs away from successfully establishing a distributed and inclusive production model.


The past four years have been humbling and instructive. I know, in retrospect, that I lacked an appreciation for how things worked on the ground when I started the project. I’ve worn different hats in front of different groups and have at times felt both inadequate and incompetent. I’ve made mistakes and appreciate now that there are a lot of things I could have done differently. That said, I’m proud of what we’ve achieved and am hopeful of what we might continue to achieve. My experiences over the past few years have been varied and sometimes distressing, but I’ve gained a lot more perspective on who I am as a person and what I believe in. I am incredibly privileged in ways I didn’t even realize existed, and my work with Protoprint has exposed me to societal truths that are otherwise brushed under rugs of entitled apathy.

With the additive development progressing independently and our filament production slowing down, I’ve recently transitioned into a part-time role at Protoprint. One of my goals over the next few months is to explore different ways to up-cycle the plastic and generate value at the waste-picker level. I’ve also been devoting my time to two other projects: An online adaptive learning platform for Indian schools and an air quality monitoring network for Pune.

The most important takeaway from the past few years has been a better understanding of the complex social landscape in India. Problems involving people and communities lacked the logical clarity of the case studies I devoured in college, but were substantially more satisfying to solve. I’m thankful for the opportunity and privilege to pursue the project and to meet so many passionate and inspiring people. All in all, it’s been a roller-coaster ride of learning and emotions, and my work in the future will be better because of it.


A brief overview of Protoprint’s Operations
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