Rice husk

Of Rice For Rice

Rice is the second most produced and demanded staple food in the world, which makes rice paddies one of the biggest sources of methane gas on earth. Almost 50% of the UK's rice comes from India, contributing to significant global greenhouse gas emissions.

Being an agrarian economy, there is a large community of farmers in India who practice rice farming. This project focuses on the rice farming community in the state of Maharashtra in Western India. It is a labour-intensive practice which produces by-products at every stage of its processing. The by-products, rice husks are either burnt, polluting the air, or allowed to decompose, which releases methane.

'Of Rice For Rice' is a community-driven initiative to utilise waste rice husks in a sustainable and regenerative way. Rice farming is practised as per seasonal cycles with a long off-season duration. During this period, farmers of this community are forced to pursue alternative temporary occupations to support their livelihood. This project aims to provide an added source of income to these farming communities using the surplus by-products, like husk, to create food containers, packaging and tableware.

The recipe for the biomaterial has been developed by using native, local ingredients and using every part of the rice from the husk to the grain. Rice husks, rice starch glue, corn starch, agar agar and glycerin are the main ingredients for the biomaterial which are sourced locally.

The designer Jui Apte has devised a methodology to standardise the process by designing a simple kit which can be used by the farmers. It includes a set of moulds created using mango wood, made by local wooden lathe artists, a custom measuring tool, a spatula and illustrated instructions in the local language. Through such interdependent collaborations, this project simultaneously engages various traditional artisan communities, to find new purposes for their craft.

This truly circular system repurposes a waste stream as a useful raw material by introducing it into the production system, thereby completing the loop.

Making process

The making process begins after the rice grain is harvested. The process has been simplified and made feasible for farmers, enabling them to produce the material without the use of specialised equipment or energy.

Preparing the rice husk:
The white rice kernel is separated from the husk in the milling process. The husks are then evenly spread and completely dried in the sun to remove any moisture. The husks are then ground into a finer-grain powder by a grinding machine at the local flour mill. The next step is to soak an adequate quantity of rice grains in water for 15 - 20 minutes. As a result, the starch from the rice grains is released into the water. In a large container, mix the desired quantity of rice husk and starch water and bring it to a boil. This mixture is allowed to rest before moving on to the next step.

Rice glue:
The process of rice production creates multiple by-products at every stage of its processing. One such by-product is broken rice (small, broken pieces of rice grain which are not fit for sale). Through this project, the designer proposes to utilise the broken rice to make rice glue as a binder, an alternative to PVA glue, which she used as a child in India. It is made by boiling rice at a high temperature and reducing it to a gelatinous paste.

Mixture:
In a separate container, cornstarch, agar agar, rice glue, glycerin and water are mixed in the appropriate ratio until it thickens. The rice husk is then added and mixed well until it forms a thick pulp. The pulp is poured into the wooden moulds and allowed to dry. Gently tap the moulds to remove air bubbles and help the mixture set evenly in the mould. It takes 1-2 days for the material to dry in the mould before it is removed. The rice husk bowl is then sun-dried for 4-5 days to completely remove the moisture.

The material can be crushed back into a powder and reused to make new products.

Text submitted by the maker and edited by the Future Materials Bank. For information about reproducing (a part of) this text, please contact the maker.