Skip to content

Anaerobic digesters and P recovery

September 16, 2014

This past summer I visited India to explore organic waste management operations that contributed to nutrient cycling. In today’s post I will discuss Jain Irrigation Systems Ltd (JISL). Founded on a philosophy that we should leave the world better than we found it, JISL pays close attention to environmental issues, farmer livelihoods, and the well being of both employees and customers. The company has a variety of operations, ranging from manufacturing solar panels and irrigation equipment, to propagating bananas and processing fruits and vegetables. While they appear to be on the leading edge of many different agricultural practices, it’s their industrial food processing and waste management that caught my attention.

As the food processing side of the company grew, management recognized they couldn’t rely on composting as their sole organic waste management approach. While they had significant amounts of land on which to dump the food waste, increasing volumes would create smell and insect problems, which could get them in trouble with local regulatory agencies.   After a number of experiments with various types of composting failed to meet their requirements, they partnered with a German company to design and build an anaerobic digester on site in 2012- the first of its kind in India.

During Mango season, processing into mango puree results in 300 tons of waste every day. The pit is mechanically sorted from the waste to be dried to be burned for energy, while the rest of the waste (~150 tons/day) is stockpiled for feeding the digester. Processing bananas, tomatoes, and onions provides additional feedstocks for the digester throughout the year, and a nearby sugar factory also sends its waste to JISL.

Not only does the digester create enough methane to run generators producing 1.7 Megawatts of power each hour, the exhaust from the generators is sent to a boiler where it makes steam, which is sent through a condenser where it creates 400 tons of refrigeration per hour for the food warehouse. Finally, the residuals from the digestion process are sent through a belt press to extract water (which is reused for irrigation, or in the digester) and the solids are sent to composting where they are mixed with other organic waste and sold back to the farmers supplying food to the factory.

Recovering and recycling P from the organic waste may have been an afterthought, but through this integrated systems approach, JISL has found an economical way to turn a waste product into energy and nutrient resources, while protecting the environment and their bottom line.

Jain AD compound

Advertisements
2 Comments leave one →
  1. Birgir Norddahl permalink
    April 12, 2015 4:26 pm

    Instead of declaring: which could bring them in trouble with local regulatory agencies, yiu and they should declare: which is not sustainable ways of treating waste. Furthermore you ought to take a short course in basic physics in order to able to bring a concise description of the processes you want to inform about. What donyou mean by: 1.7 MW each hour? Think about it – otherwise a fair description and interesting. Next time yiu should go Denmark and observe the many ways anaerobic digestion can be exploited. Perhaps also to Lithuania, where the plant: Kurana UAB In Pasvalys is worth a description.

    • Jared Stoltzfus permalink
      June 16, 2015 12:42 am

      I’m not sure if I understand all your comments, but will try to address them: Composting was working for them at small scale, but as they grew they needed a more sustainable option, and found anaerobic digestion to be the optimal solution for their site. I’m sure there are a number of other locations around the world (even around the US) that are taking a similar approach.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: