STiR coffee and tea magazine

32 STiR coffee and tea | 2025 Quarter 2 Summer (Jun/jul/Aug) "Besides the impact on the environ- ment, ESP filters will definitely make your neighbors happier and will reduce the number of questions from your local authorities," shares Denys Nickolaienko, head coffee roaster at Manhattan Coffee Roasters. "It would have a huge positive impact on the neighborhood." Filtering coffee roasting smoke re- quires something that can filter large amounts of air without reducing the air- flow, while also being able to handle very high temperatures. Alternative filtration technologies like a water-based filter or a HEPA filter are generally not feasible for coffee roasting. ESP filters can han- dle the oily, carbon-laden roasting smoke particles. The Challenges of Using ESP Filters While the ESP filters offer proven ben- efits for helping reduce emissions, espe- cially particulate matter and VOCs, they also pose some challenges along the way. ESP filters need to filter the outgo- ing smoke, therefore, they act as a wall or a thick curtain for the airflow. If the air- flow metrics aren't calculated correctly, the filter's effectiveness is reduced, the roaster can become clogged, and roasting profiles altered. "Our 1950s Probat at Manhattan did not generate enough airflow for both it- self and the filter, and we needed to in- stall an additional fan on the roof to suck the air, but after installing both the ESP filter and the fan all our profiles needed adjustments," says Nickolaienko. "The ESP filters also require regular maintenance, which can get tedious," he adds. "If not cleaned properly, the filters could start blocking the airflow. Once this happens, you might get a backward airflow in the roaster, and all the coffees could start adsorbing smoky flavors from the exhaust. Depending on the amount of roasting, airflow, and smoke generat- ed, regular maintenance and cleaning are a must. For our unit, it means cleaning every 3 to 4 weeks." From RO filters for drinking water to air filters in air conditioning units, all filtration technologies require regular cleaning and maintenance to ensure they remain functional with maximum effica- cy. ESP filters are no exception. Cleaning the ESP filters usually involves cleaning their parts with water. Some waste, like the chaff particles, can be composted or discarded in industrial waste. Oil and tar-like residues on the filters should be scraped and cleaned to prevent excessive build-up. They would need to be dis- carded as industrial waste and cannot be composted. ROIs Beyond Just Monetary Gains "The ROI typically ranges from 2 to 5 years, depending on fuel savings, reduced filter replacement costs, and regulatory benefits," explains Dwarkanath. "If an ESP allows a roastery to avoid an after- burner, the savings on fuel and mainte- nance can be tens of thousands of dollars per year." Depending on the capacity and cus- tomization, ESP filters could cost any- where between $5,000 to $50,000. They have low ongoing costs and require only occasional component replacements if cleaned and maintained well. "The general rule of thumb is the smaller your roaster, the higher the cost of the ESP filters, compared to the price of the roaster," shares Nickolaienko. "But the filter allowed us to run our roaster in the middle of our café without any connection to exhaust, so that made a lot of sense for us." Sustainability and the Future of ESP Filters For any roasters genuinely interested in reducing the carbon footprint and envi- ronmental impact of their existing coffee roaster, installing an electrostatic pre- cipitation filter makes sense. While the smoke itself pollutes the environment, the smoky odors can also be very annoy- ing for the neighborhood, and an ESP fil- ter can play a huge role in reducing both. However, for roasters with a larger impact, looking at the bigger picture, switching from a gas-fueled roaster to an electric roaster would be ideal. All lead- ing roaster brands are now offering cof- fee roasters powered by electricity in line with offering more sustainable and eco- friendly solutions to the market. The journey to a perfect cup of cof- fee doesn't have to leave a bitter taste on the environment. While electrostatic precipitation filters may require initial investment and regular maintenance, their remarkable ability to capture roast- ing emissions makes them a powerful ally in the quest for sustainable coffee production. Think of them as the silent guardians of clean air, tirelessly working to ensure that the only thing a roastery releases into the atmosphere is the irre- sistible aroma of freshly roasted coffee. For roasters committed to both qual- ity and environmental stewardship, ESP filters are not just an option–they are an essential ingredient in the recipe for a more sustainable coffee industry. After all, shouldn't coffee's impact focus on brightening someone's morning, rather than dimming the planet's future? According to Suhas Swarakanath, founder of Benki Brewing Tools and Specialty Coffee Academy of India, an ESP filter can help achieve up to 95% reduction in particulate matter emissions, 20-50% reduction in volatile organic compounds, and 30-50% reduction in natural gas consumption (when replacing afterburners). Depending on the amount of roasting, airflow, and smoke generated, regular maintenance and cleaning are a must. Photo courtesy Manhattan Coffee Roasters

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