Rice Straw to Biochar

Rice Straw to Biochar

Capacity to Deliver

The issue

In a full irrigation water allocation year, several hundred thousand tonnes of rice straw is generated in the region. The degradation of rice crop residue causes significant release of CH4 as a greenhouse gas, as well as the release of other various air pollutants including particulate matter (PM2.5 and PM10) when burnt. In addition, there is a current stockpile of @100k/tn of rice hulls generated post rice milling that need a repurposing solution. This proposal investigates the use of rice straw as a feedstock for biochar, wood vinegar and bioenergy production as a waste utilisation and value-add opportunity. Converting crop residue to biochar also improves environmental outcomes by improving air quality and reducing greenhouse gas emissions.

The solution

There are many unknowns about the conversion of rice straw to biochar via pyrolysis, and concerns have been raised about the composition of rice straw for use in biochar production, in particular its apparent high silica content. As such Western Murray Land Improvement Group (WMLIG} is sending rice straw to be trialled by Earth Systems using their pyrolysis unit (Charmaker) via funding from the Federal Government's Murray Darling Basin Economic Development Program, and a co-contribution from Murray Local Land Services. This initial trial will be used as a steppingstone to further explore options for organic waste conversion to biochar in the region, and it is envisioned that a consortia of industry, researchers, government and community group members will join the established biochar cluster group for knowledge sharing and further scope a range of use options in the future.

The impact

The following outcomes will be achieved by the trial: Basic case study report on conversion efficiency of feedstock to biochar and lessons learned, Chemical analysis of biochar emission from stack, feedstock handling, and wood vinegar Basic cost/ benefit analysis of producing biochar from rice straw and other by-product options. Provide MLLS an opportunity to participate in a Biochar steering committee to be initiated by WMLIG.

This project is being delivered via funding from the Australian Government's Murray Darling Basin Economic Development Program and Murray Local Land Services

Project Partners