Processing waste biomass to reduce airborne emissions

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Thursday, September 29, 2022

To prepare fields for planting, farmers the world over often burn corn stalks, rice husks, hay, straw, and other waste left behind from the previous harvest. In many places, the practice creates huge seasonal clouds of smog, contributing to air pollution that kills 7 million people globally a year, according to the World Health Organization. Annually, $120 billion worth of crop and forest residues are burned in the open worldwide — a major waste of resources in an energy-starved world, says Kevin Kung SM ’13, PhD ’17. Kung is working to transform this waste biomass into marketable products — and capitalize on a billion-dollar global market — through his MIT spinoff company, Takachar. Founded in 2015, Takachar develops small-scale, low-cost, portable equipment to convert waste biomass into solid fuel using a variety of thermochemical treatments, including one known as oxygen-lean torrefaction. The technology emerged from Kung’s PhD project in the lab of Ahmed Ghoniem, the Ronald C. Crane (1972) Professor of Mechanical Engineering at MIT. Biomass fuels, including wood, peat, and animal dung, are a major source of carbon emissions — but billions of people rely on such fuels for cooking, heating, and other household needs. “Currently, burning biomass generates 10 percent of the primary energy used worldwide, and the process is used largely in rural, energy-poor communities. We’re not going to change that overnight. There are places with no other sources of energy,” Ghoniem says. What Takachar’s technology provides is a way to use biomass more cleanly and efficiently by concentrating the fuel and eliminating contaminants such as moisture and dirt, thus creating a “clean-burning” fuel — one that generates less smoke. “In rural communities where biomass is used extensively as a primary energy source, torrefaction will address air pollution head-on,” Ghoniem says. Thermochemical treatment densifies biomass at elevated temperatures, converting plant materials that are typically loose, wet, and bulky into compact charcoal. Centralized processing plants exist, but collection and transportation present major barriers to utilization, Kung says. Takachar’s solution moves processing into the field: To date, Takachar has worked with about 5,500 farmers to process 9,000 metric tons of crops. Takachar estimates its technology has the potential to reduce carbon dioxide equivalent emissions by gigatons per year at scale. (“Carbon dioxide equivalent” is a measure used to gauge global warming potential.) In recognition, in 2021 Takachar won the first-ever Earthshot Prize in the clean air category, a £1 million prize funded by Prince William and Princess Kate’s Royal Foundation. Roots in Kenya As Kung tells the story, Takachar emerged from a class project that took him to Kenya — which explains the company’s name, a combination of takataka, which mean “trash” in Swahili, and char, for the charcoal end product. It was 2011, and Kung was at MIT as a biological engineering grad student focused on cancer research. But “MIT gives students big latitude for exploration, and I took courses outside my department,” he says. In spring 2011, he signed up for a class known as 15.966 (Global Health Delivery Lab) in the MIT Sloan School of Management. The class brought Kung to Kenya to work with a nongovernmental organization in Nairobi’s Kibera, the largest urban slum in Africa. “We interviewed slum households for their views on health, and that’s when I noticed the charcoal problem,” Kung says. The problem, as Kung describes it, was that charcoal was everywhere in Kibera — piled up outside, traded by the road, and used as the primary fuel, even indoors. Its creation contributed to deforestation, and its smoke presented a serious health hazard. Eager to address this challenge, Kung secured fellowship support from the MIT International Development Initiative and the Priscilla King Gray Public Service Center to conduct more research in Kenya. In 2012, he formed Takachar as a team and received seed money from the MIT IDEAS Global Challenge, MIT Legatum Center for Development and Entrepreneurship, and D-Lab to produce charcoal from household organic waste. (This work also led to a fertilizer company, Safi Organics, that Kung founded in 2016 with the help of MIT IDEAS. But that is another story.) Meanwhile, Kung had another top priority: finding a topic for his PhD dissertation. Back at MIT, he met Alexander Slocum, the Walter M. May and A. Hazel May Professor of Mechanical Engineering, who on a long walk-and-talk along the Charles River suggested he turn his Kenya work into a thesis. Slocum connected him with Robert Stoner, deputy director for science and technology at the MIT Energy Initiative (MITEI) and founding director of MITEI’s Tata Center for Technology and Design. Stoner in turn introduced Kung to Ghoniem, who became his PhD advisor, while Slocum and Stoner joined his doctoral committee. Roots in MIT lab Ghoniem’s telling of the Takachar story begins, not surprisingly, in the lab. Back in 2010, he had a master’s student interested in renewable energy, and he suggested the student investigate biomass. That student, Richard Bates ’10, SM ’12, PhD ’16, began exploring the science of converting biomass to more clean-burning charcoal through torrefaction. Most torrefaction (also known as low-temperature pyrolysis) systems use external heating sources, but the lab’s goal, Ghoniem explains, was to develop an efficient, self-sustained reactor that would generate fewer emissions. “We needed to understand the chemistry and physics of the process, and develop fundamental scaling models, before going to the lab to build the device,” he says. By the time Kung joined the lab in 2013, Ghoniem was working with the Tata Center to identify technology suitable for developing countries and largely based on renewable energy. Kung was able to secure a Tata Fellowship and — building on Bates’ research — develop the small-scale, practical device for biomass thermochemical conversion in the field that launched Takachar. This device, which was patented by MIT with inventors Kung, Ghoniem, Stoner, MIT research scientist Santosh Shanbhogue, and Slocum, is self-contained and scalable. It burns a little of the biomass to generate heat; this heat bakes the rest of the biomass, releasing gases; the system then introduces air to enable these gases to combust, which burns off the volatiles and generates more heat, keeping the thermochemical reaction going. “The trick is how to introduce the right amount of air at the right location to sustain the process,” Ghoniem explains. “If you put in more air, that will burn the biomass. If you put in less, there won’t be enough heat to produce the charcoal. That will stop the reaction.” About 10 percent of the biomass is used as fuel to support the reaction, Kung says, adding that “90 percent is densified into a form that’s easier to handle and utilize.” He notes that the research received financial support from the Abdul Latif Jameel Water and Food Systems Lab and the Deshpande Center for Technological Innovation, both at MIT. Sonal Thengane, another postdoc in Ghoniem’s lab, participated in the effort to scale up the technology at the MIT Bates Lab (no relation to Richard Bates). The charcoal produced is more valuable per ton and easier to transport and sell than biomass, reducing transportation costs by two-thirds and giving farmers an additional income opportunity — and an incentive not to burn agricultural waste, Kung says. “There’s more income for farmers, and you get better air quality.” Roots in India When Kung became a Tata Fellow, he joined a program founded to take on the biggest challenges of the developing world, with a focus on India. According to Stoner, Tata Fellows, including Kung, typically visit India twice a year and spend six to eight weeks meeting stakeholders in industry, the government, and in communities to gain perspective on their areas of study. “A unique part of Tata is that you’re considering the ecosystem as a whole,” says Kung, who interviewed hundreds of smallholder farmers, met with truck drivers, and visited existing biomass processing plants during his Tata trips to India. (Along the way, he also connected with Indian engineer Vidyut Mohan, who became Takachar’s co-founder.) “It was very important for Kevin to be there walking about, experimenting, and interviewing farmers,” Stoner says. “He learned about the lives of farmers.” These experiences helped instill in Kung an appreciation for small farmers that still drives him today as Takachar rolls out its first pilot programs, tinkers with the technology, grows its team (now up to 10), and endeavors to build a revenue stream. So, while Takachar has gotten a lot of attention and accolades — from the IDEAS award to the Earthshot Prize — Kung says what motivates him is the prospect of improving people’s lives. The dream, he says, is to empower communities to help both the planet and themselves. “We’re excited about the environmental justice perspective,” he says. “Our work brings production and carbon removal or avoidance to rural communities — providing them with a way to convert waste, make money, and reduce air pollution.” This article appears in the Spring 2022 issue of Energy Futures, the magazine of the MIT Energy Initiative.

MIT spinoff Takachar converts agricultural waste into clean-burning fuel, and wins Earthshot Prize.

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Pennsylvania’s first proposed hazardous waste landfill would be near homes and schools

PITTSBURGH — A landfill company based in Pittsburgh has applied for a permit to open the first hazardous waste landfill in the state of Pennsylvania, which some fear could threaten waterways and increase air pollution. Hazardous waste includes anything potentially dangerous or harmful to human health or the environment. It includes things like cleaning chemicals, paint and solvents, corrosive or toxic industrial waste, sludge from air pollution control units and waste from the oil and gas industry, including potentially radioactive substances. Federal regulations require these waste products to be handled and disposed of with special care. The company that would build the new hazardous waste landfill, MAX Environmental Technologies, Inc., is headquartered in Pittsburgh and operates two landfills in the nearby communities of Yukon and Bulger. The Yukon facility, which is about 29 miles southeast of Pittsburgh, stores and treats this type of waste, but isn’t permitted to dispose of it on site, so any waste that remains hazardous after treatment must be transported out of state for disposal. If MAX’s permit is granted, the company will construct a new hazardous waste landfill on its Yukon property, which is within one mile of 485 homes and about two and a half miles from the Yough School District. Residents in the area have spent decades fighting to close the existing landfill due to concerns that it’s too close to homes and schools and fears that the hazardous pollution it emits is causing health problems. “We moved there as newlyweds in our first home in the 1980s, and shortly after we moved there my husband and I started to experience all kinds of health problems,” Diana Steck told EHN, noting that at the time, the landfill was owned by a different company, Mill Services. “My husband developed this terrible rash that was on his face and his back and arms, and I had problems with asthma and started to have issues with unexplained joint pain.” After Steck’s children were born, they started experiencing unusual health issues too. She saw orange plumes rising from the site and said the acrid smells gave her family blisters in their nostrils and mouths. After reading a news story about the landfill releasing toxic pollutants like heavy metals, arsenic and chromium compounds into the air and water, she joined a group of residents who were also worried about the health impacts, and spent the next several decades unsuccessfully fighting to see the landfill closed. Steck has since moved about 10 miles away, but remains worried. “The community has been deemed a sacrifice zone,” she said. “This new landfill would be even closer to homes, and it would be closer to Sewickley Creek, a tributary of the Youghiogheny River, which is a drinking water source for many people downstream. Everyone who lives in this area, even those who are further away from the landfill, should be concerned about this.” More recently, public outcry erupted when MAX Environmental petitioned to have some of the waste it handles reclassified as non-hazardous. Environmental advocates say the company hasn’t been a good neighbor. “The existing facility is chronically noncompliant,” Melissa Marshall, an attorney and community advocate at the Mountain Watershed Association, told EHN, adding that the facility ranks among the top facilities in the state for violations of its water discharge permit. “A company that can’t follow regulations designed to keep our waterways safe shouldn’t be trusted to become the first hazardous waste landfill in the state.” Meanwhile, the plant’s operators told EHN that they run the site safely and take all the precautions necessary to protect the environment and surrounding communities. “We’re obviously aware there have been exceedances of our discharge limits in the past,” said Carl Spadaro, who previously worked as an engineer for the Pennsylvania Department of Environmental Protection and now serves as the environmental manager for MAX Environmental Technologies. “Over the last few years, we’ve increased the maintenance of our wastewater treatment system so we’re keeping it as clean as possible.” What’s next, and how can residents weigh in?The Pennsylvania Department of Environmental Protection (DEP) is holding a public meeting and public hearing on the first stage of the permit application on the evening of Thursday, Dec.1. The agency will also collect public comments about the proposed landfill until Jan. 20, 2023. DEP spokesperson Lauren Camarda noted that this hearing marks the beginning of a lengthy and comprehensive permitting process and said only topics related to siting regulations will be discussed at this first hearing. “The review process for a hazardous waste disposal facility is a prescriptive and multi-phase process and we are in phase I,” Camarda told EHN. “It is important to stress that if the phase I application is approved, there is still a phase II application that must be submitted that comes with its own comprehensive review process, including a public participation process.” If the application makes it through the first two phases without being denied by DEP, the agency will publish a notice of draft permit or intent to deny, and there will be additional public hearing and comment periods. “Normally they try to put sites like this as far away from people as they can,” Marshall said. “It’s very unusual to try and put a hazardous waste landfill this close to people’s homes… so it’s really important for the community to come participate in these hearings.”

PITTSBURGH — A landfill company based in Pittsburgh has applied for a permit to open the first hazardous waste landfill in the state of Pennsylvania, which some fear could threaten waterways and increase air pollution. Hazardous waste includes anything potentially dangerous or harmful to human health or the environment. It includes things like cleaning chemicals, paint and solvents, corrosive or toxic industrial waste, sludge from air pollution control units and waste from the oil and gas industry, including potentially radioactive substances. Federal regulations require these waste products to be handled and disposed of with special care. The company that would build the new hazardous waste landfill, MAX Environmental Technologies, Inc., is headquartered in Pittsburgh and operates two landfills in the nearby communities of Yukon and Bulger. The Yukon facility, which is about 29 miles southeast of Pittsburgh, stores and treats this type of waste, but isn’t permitted to dispose of it on site, so any waste that remains hazardous after treatment must be transported out of state for disposal. If MAX’s permit is granted, the company will construct a new hazardous waste landfill on its Yukon property, which is within one mile of 485 homes and about two and a half miles from the Yough School District. Residents in the area have spent decades fighting to close the existing landfill due to concerns that it’s too close to homes and schools and fears that the hazardous pollution it emits is causing health problems. “We moved there as newlyweds in our first home in the 1980s, and shortly after we moved there my husband and I started to experience all kinds of health problems,” Diana Steck told EHN, noting that at the time, the landfill was owned by a different company, Mill Services. “My husband developed this terrible rash that was on his face and his back and arms, and I had problems with asthma and started to have issues with unexplained joint pain.” After Steck’s children were born, they started experiencing unusual health issues too. She saw orange plumes rising from the site and said the acrid smells gave her family blisters in their nostrils and mouths. After reading a news story about the landfill releasing toxic pollutants like heavy metals, arsenic and chromium compounds into the air and water, she joined a group of residents who were also worried about the health impacts, and spent the next several decades unsuccessfully fighting to see the landfill closed. Steck has since moved about 10 miles away, but remains worried. “The community has been deemed a sacrifice zone,” she said. “This new landfill would be even closer to homes, and it would be closer to Sewickley Creek, a tributary of the Youghiogheny River, which is a drinking water source for many people downstream. Everyone who lives in this area, even those who are further away from the landfill, should be concerned about this.” More recently, public outcry erupted when MAX Environmental petitioned to have some of the waste it handles reclassified as non-hazardous. Environmental advocates say the company hasn’t been a good neighbor. “The existing facility is chronically noncompliant,” Melissa Marshall, an attorney and community advocate at the Mountain Watershed Association, told EHN, adding that the facility ranks among the top facilities in the state for violations of its water discharge permit. “A company that can’t follow regulations designed to keep our waterways safe shouldn’t be trusted to become the first hazardous waste landfill in the state.” Meanwhile, the plant’s operators told EHN that they run the site safely and take all the precautions necessary to protect the environment and surrounding communities. “We’re obviously aware there have been exceedances of our discharge limits in the past,” said Carl Spadaro, who previously worked as an engineer for the Pennsylvania Department of Environmental Protection and now serves as the environmental manager for MAX Environmental Technologies. “Over the last few years, we’ve increased the maintenance of our wastewater treatment system so we’re keeping it as clean as possible.” What’s next, and how can residents weigh in?The Pennsylvania Department of Environmental Protection (DEP) is holding a public meeting and public hearing on the first stage of the permit application on the evening of Thursday, Dec.1. The agency will also collect public comments about the proposed landfill until Jan. 20, 2023. DEP spokesperson Lauren Camarda noted that this hearing marks the beginning of a lengthy and comprehensive permitting process and said only topics related to siting regulations will be discussed at this first hearing. “The review process for a hazardous waste disposal facility is a prescriptive and multi-phase process and we are in phase I,” Camarda told EHN. “It is important to stress that if the phase I application is approved, there is still a phase II application that must be submitted that comes with its own comprehensive review process, including a public participation process.” If the application makes it through the first two phases without being denied by DEP, the agency will publish a notice of draft permit or intent to deny, and there will be additional public hearing and comment periods. “Normally they try to put sites like this as far away from people as they can,” Marshall said. “It’s very unusual to try and put a hazardous waste landfill this close to people’s homes… so it’s really important for the community to come participate in these hearings.”

Experts say COP27’s ‘plastic waste pyramid’ is focusing on the wrong solution

Some call it a missed opportunity to push for plastic production cuts.

In the middle of the Egyptian desert, just outside Cairo, a new sculpture has gained the singular distinction of being the world’s “largest plastic waste pyramid.” Measuring nearly 33 feet high and weighing some 18 metric tons, the sculpture — made of plastic litter removed from the Nile — is truly gargantuan. The sculptors behind say it should serve as a stark message to leaders at COP27, the international climate conference that began in Sharm el-Sheikh last week, about the “incredible crisis” of plastic pollution. “Our installation will really draw attention to the scale of the problem of plastic waste in our rivers and oceans,” Justin Moran, founder of Hidden Sea, a wine company that co-sponsored the art installation, told Packaging News. The brand, which targets “socially conscious consumers” is using the sculpture to launch an initiative called 100YR CLEANUP, which is supposed to raise enough money to continuously remove plastic from the environment for the next 100 years. The plastic pyramid is eye-catching, but some environmental advocates say its focus on plastic cleanup is behind the times. They argue that what’s needed now is public pressure on policymakers and the petrochemical industry to stop making so much plastic in the first place. “I’m not saying we shouldn’t do cleanup,” said Thalia Bofiliou, a senior investment analyst for the nonprofit financial think tank Planet Tracker, “but we shouldn’t do only that.” Plastic and packaging companies are planning to make more and more plastics, Biofilou said, and unless they “take responsibility and reduce plastic production, then the issue is not going to be resolved.” There are already 140 million metric tons of plastic in the planet’s oceans and rivers. By 2060, the Organization for Economic Cooperation and Development estimates that number will skyrocket to nearly half a billion metric tons, with annual plastic leakage to the natural world doubling to 44 million metric tons a year. Meanwhile, the 100YR CLEANUP is pledging to remove 1,500 water bottles’ worth of plastic from the environment for every $100 it raises.  The 100YR CLEANUP isn’t trying to clean up the planet on its own: Considering that the weight of a standard 600-milliliter water bottle is 0.93 ounces, the initiative would need to raise roughly $1.26 trillion to scoop up the world’s plastic pollution by 2060 — and then raise $113 billion each subsequent year to try to keep up with the still-accumulating piles of plastic bottles, bags, cutlery, and other trash. But even similar removal efforts haven’t made a dent in existing plastic pollution to date. The Alliance to End Plastic Waste, an industry-founded nonprofit whose members include major polluters like Exxon Mobil, Shell, and the plastic-maker Braskem, only managed to collect about 4,000 metric tons of plastic trash over the first three years of its existence — just 0.04 percent of its own waste collection goal and about 0.006 percent of the plastic pollution that was generated during that time. Another sculpture, featured in Nairobi, Kenya, as the U.N. discussed a global plastics treaty, depicted plastic trash pouring out of a giant spout. Jamies Wakibia / SOPA Images / LightRocket via Getty Images Instead of just calling for more cleanups, Biofilou said advocates should spotlight companies that are responsible for plastic pollution and demand they be held accountable. Given the plastic waste pyramid’s proximity to COP27, the Coca-Cola Company could have been an easy target; the multinational beverage manufacturer is sponsoring the climate conference but has lobbied against legislation to address the plastics crisis. It was recently ranked the world’s biggest plastic polluter for the fourth year straight.  The pyramid is not the first piece of public art designed to call international attention to the plastic crisis. Another sculpture, featured over the summer as the United Nations discussed a global treaty on plastics, depicted plastic trash pouring out of a giant spout, urging policymakers to stem the metaphorical flow. Hidden Sea co-sponsored both the giant spout installation and the new plastic waste pyramid. Moran, Hidden Sea’s founder, told Grist “we need to turn the plastic tap off.” A spokesperson for the pyramid’s other co-sponsor, Zero Co, a body care and cleaning product company that makes refillable packaging, told Grist the business also supports “the elimination of producing or using single-use plastics.” They said the business hasn’t focused on this messaging in pyramid press materials because it “didn’t want to delve too far away from the story and complicate messaging.”  Aarthi Ananthanarayanan, director of the nonprofit Ocean Conservancy’s climate and plastics initiative, defended plastic cleanups and the waste pyramid. Despite the enormity of the plastic pollution problem, she said cleaning up even a small amount of plastic trash can engage and benefit local communities. She stressed, however, the need to highlight plastics’ entire life cycle and cradle-to-grave impacts — including not only how they mar rivers and beaches but how their production contributes to climate change. “What I wish they would have said is, ‘Plastics are fossil fuels — this is a pyramid of fossil fuel waste,’” Ananthanarayanan said. They didn’t, but if publicity around the waste sculpture helps draw that connection even a little bit she added, “I’ll take it.” This story was originally published by Grist with the headline Experts say COP27’s ‘plastic waste pyramid’ is focusing on the wrong solution on Nov 14, 2022.

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