Bio-CNG Plant Reduces Air Pollution in Indore, India, but Waste Odor Remains a Challenge
Bio-compressed natural gas (bio-CNG) is a coming-of-age technology that can deal with air pollution at various levels. However, the industry has not picked it up despite economic and environmental promises. Bio-CNG helps deal with air pollution on three levels—curtail methane emission, ward off waste burning and phase out fossil fuel powered vehicles. A ground report from Indore, Madhya Pradesh, India, might help us better understand its challenges. Indore has Asia’s largest bio-CNG plant from city waste. The plant is located in Devguradiya village on the outskirts of the city. Besides its famous Devi Ahilya temple, Devguradiya was notorious for being the dumping ground of Indore’s garbage for 70 years. “Either smoke or rotting smell enveloped this region at all times of the day,” said Snehlata Thakur, a teacher at the Government Middle School in Devguradiya. “We kept the windows bolted to be able to teach. Many a time, children would not even come to school.” Thakur has been working in this school for six years. “The smell is still there but is not as bad. The attendance has also gone up,” she said happily. Clean Indore but Devguradia stuck with odor Though the "trenching ground" in Devguradia has been replaced by a city forest and the bio-CNG plant, the putrefying odor of garbage still marks the area. “I burned 200 packets of incense this summer to mask the smell from the plant. At night, it becomes unbearable,” said Shivalya Chaurasia, owner of the Chaurasia Paan Bhandar, one of the 24x7 shops across the road from the bio-CNG plant. This reporter spent time near Devguradiya in the summer as well as during monsoon. The odor was persistent in both seasons but especially terrible in the monsoon—extending to areas up to five kilometers away, depending on wind direction. The bad odor in garbage is due to hydrogen sulfide (H2S) and ammonia which is released when garbage decomposes aerobically, said an SWM expert at the Centre for Science and Environment, New Delhi. Short-term exposure to H2S can cause coughing, eye irritation, headache, nausea, breathing difficulties and more.
