Harvest seasons in India generate millions of tons of agricultural residue from rice straw to sugarcane bagasse. While some of this goes into fuel or animal feed, rice straw is still burned in fields to clear land, generating air pollution and CO2. But it doesn’t have to be this way, says Bangalore-based startup altM.
What if you could both prevent such environmental damage and use these materials to replace products currently produced by petrochemicals, from ingredients used in industrial adhesives to rheology modifiers used in cosmetics?
While a lot of attention has been focused on biomaterials produced by microbes in fermentation tanks, say altM founders Apoorv Garg (CEO) and Yugal Raj Jain (COO), altM has developed a more cost-effective thermochemical approach to “engineer waste into purpose.”
According to Garg, who met Raj Jain while working as an engineer at Tesla a few years ago, “Most of everything around us is made from three molecules: ethylene, propylene, and benzene [foundational building blocks in the petrochemical industry]. So we started looking at alternatives, the angle always being, is it commercially viable and scalable from an engineering and manufacturing standpoint?”
He added: “For example, enzymatic systems are very difficult to scale when you’re trying to build continuous, high-volume products, although they work pretty well for small batch high value molecules. So we decided to focus on thermochemical processes, but with reduced energy and chemical requirements to improve the sustainability of the process.”
Patented process
In simple terms, he said, altM is applying heat and chemicals in a patented process to break ag biomass into fractions then separating and purifying them and then converting them into higher value products.
“We can handle any kind of lignocellulosic biomass, so we can take rice straw, wheat straw, sugarcane bagasse, hemp and cotton textile waste, grasses, and bioethanol refinery waste. We then deconstruct it with thermochemical fractionation, a process we’ve optimized at < 170⁰C, without spending any energy on applying any additional pressure, with less than 3% chemicals by weight of the overall crop residue.
“We then take these deconstructed fractions and upgrade them using novel pathways into the final materials.”
In comparison, he said, “If you look at petrochemicals, you’re talking about 850⁰C temperatures and 10-15-bar pressures, and depending on which molecule you’re building, significantly higher chemical use.”
The science behind the tech has been driven by chief scientific officer Harshad Velankar, PhD, said Garg. “Dr. Arshad has spent 20 years researching the transformation of biomass, both at a fundamental research level and applied research level.
“He did his PhD in the subject, did his post-doctoral work in South Africa and the US, and worked for two of the largest technology and chemical companies in India, Praj Industries and Reliance Life Sciences. He then led the bioprocessing lab at one of the largest oil and gas companies in India [Hindustan Petroleum].”
Throughput and yield
The focus now is on scaling up, said Garg, who said altM is a couple of months away from completing its pilot production unit, which will enable it to produce tons, rather than kilos, of material. “We have 26 different molecules at the lab scale, six of which we’re translating to [the slightly larger] demo scale, with the goal that we’ll take three to our pilot plant to be commercialized.”
For a chemical plant, said Garg, the two things that matter are throughput and yield. Put simply, “how much can I process per hour and what’s my output from each kilo of feedstock?”
For the pilot plant, he said, “We will select one molecule from cellulose, one from lignin, and one from hemicellulose. We need to use as many fractions of the biomass as we can, so we are looking at a rheology modifier—a viscosity modifier for cosmetics—built from cellulose, xylan from hemicellulose that has applications in gut health, and then from lignin we’re looking at a 100% formaldehyde-free adhesive wood adhesive or a UV blocker for cosmetics.”
altM is already working with cosmetic formulators in India on the viscosity modifier and will start large scale trials shortly, he said.
Pre-processing
As for how much it costs to source the agri-waste that altM is using as its raw material, the value chain is still evolving, he said. “There is no fixed price today. If I go to a sugar mill, it will charge me [for bagasse], because there are other people who buy it for different applications. But for other raw materials such as rice straw it varies.”
Different agri-residues also come with different pre-processing requirements, he added. “Rice straw coming directly from the field may need a significant amount of pre-processing, whereas industrial waste like sugar cane bagasse and textile waste requires very little pre-treatment at our end. And then finally, biorefinery waste is already a viscous liquid so has even lower requirements.”
Next steps
altM raised $3.5 million in August 2023 in a round led by Omnivore, and has “been quite capital efficient,” said Garg. “Mostly, we have spent this money to build our pilot facility, which will have 50 tons of annual capacity, and we are going to go for early customer revenue starting Q4 of this calendar year.
“These are not going to be revenues that can make us sustainable, but they will showcase the technology and the real need for the materials that we’re building. Then it’s a case of optimizing the pilot facility to get the right process parameters to build a commercial facility, which we want to build in Q4, 2026/Q1, 2027.”
As for investors, he said, the fact that altM had done technology due diligence with Wageningen University in the Netherlands provided some confidence in the early days, along with validation from some early customers.
As for the competitive set, several companies are working with agricultural residues to create materials, “but they mostly try to utilize one part of the biomass,” he said, “Whereas we are trying to utilize as many fractions of the biomass as we can to increase our overall yield.”
Further reading:
NEW REPORT: Agrifoodtech funding in developing markets surges 63%, bucking global decline
