Fueling agriculture with food waste

According to the Food and Agriculture Organization (FAO) of the United Nations, food waste and loss accounts for 8 percent of global greenhouse gas emissions. The challenges of finding innovative ways to reintegrate waste and put it into proper use have been heavy.

The Sustainable Development Division of the College of Science and Engineering at Hamad Bin Khalifa University (HBKU) in Qatar has been spearheading the Moistchar project that aims to reduce food waste in Qatar and support the country as it works towards achieving its long-term sustainability goals.

 “We wanted to take the food waste and convert it into a product that we can use to enhance agricultural productivity,” said Professor Gordon Mackey of the Sustainable Development Division.

Composting is one way to turn food waste to agricultural use, but we found that it is more efficient to turn food waste into biochar, which is a very carbon-rich product that can be put back into Qatar’s soil, which is carbon deficient,” explained Dr. Mackey.

Biochar is organic with no chemicals used in the production process. To develop a mineral-rich product, the food waste is put through a process called pyrolysis whereby the waste is dried through a heating process. The process ensures that the char can be applied to the soil, which produces a number of subsequent benefits, and enhances the microbial quality of the soil. Most notably, biochar enhances the nitrogen turnover which means agricultural soil would require less fertilizer, and results in the bacteria extracting nitrogen out of the atmosphere.

Biochar also enhances the water efficiency of the soil. So, if you have very coarse sandy soil, at the biochar level, it is often finer, which helps to hold the water. But its surface properties also allow it to absorb the water. So the project can reduce the amount of water that is used for irrigation.

Dr. Mackey notes that the Moistchar project is making strides towards reducing substantial food waste in Qatar, and that in the second phase of the project the team would examine waste from a broader perspective, considering not only food waste but all other types of biomass waste.

“Qatar is striving to become more food self-sufficient and has made big strides in that area, but to produce food requires water and in Qatar, producing water requires a lot of energy. This has been an important objective for the project since the beginning. This is where we really anticipate the benefits for sustainability; in reducing the overall environmental burdens of food production,” said Dr. Mackey.