Rice husk, once treated as a low-value byproduct of paddy milling, is emerging as a key raw material in the paddy-rich West Godavari district for a fast-growing green silica industry, attracting policymakers, industrialists, and investors.

West Godavari and Eluru districts together produce nearly 25 lakh metric tonnes of paddy annually. After milling, nearly 19% of the output, about 4.75 lakh metric tonnes, remains as paddy husk.

For decades, most of it was either burned as low-grade boiler fuel or discarded near rice mills. Now, the same byproduct is being converted into high-value industrial material.

Through controlled combustion, rice husk is transformed into Rice Husk Ash (RHA), which contains over 90 per cent silica. The silica is processed into products such as precipitated silica and silica gel, both witnessing rising demand in domestic and international markets.

Officials said that the automotive sector was driving much of this demand. Industry estimates indicate that the tyre and rubber industry alone accounts for nearly 57 per cent of the global silica market.

Wide scope

Tyre manufacturers are increasingly adopting rice-husk-derived silica for producing fuel-efficient ‘green tyres’ with improved tensile strength, durability, and lower rolling resistance, while also reducing dependence on environmentally damaging mined silica.

The applications extend beyond tyres. Silica gel derived from rice husk ash is widely used in electronics for moisture protection, in toothpaste and cosmetics as a thickening agent, and in the food industry as an anti-caking material.

“The West Godavari district administration has submitted a Circular Economy Blueprint to the Andhra Pradesh government to transform the district into a zero-waste industrial hub by encouraging rice millers to diversify into value-added industries. More than 500 rice millers recently attended meetings in Bhimavaram to explore opportunities in silica extraction, rice bran oil production, and biomass energy generation,” Collector Chadalavada Nagarani told The Hindu.

She said investments are gathering momentum, with companies such as Gowthami Solvent Oils already operating processing facilities, while new silica manufacturing projects worth nearly ₹30 crore are being developed under the MSME framework.

The Andhra Pradesh Food Processing Policy 2024-29 offers incentives, including a 25 per cent capital subsidy and 7 per cent interest subsidy for eligible units, the Collector said.

Ms. Nagarani said industry estimates suggest refined silica gel can fetch nearly ₹200 per kilogram, significantly enhancing the value of agricultural waste.

For Andhra Pradesh, which produces nearly 70 lakh metric tonnes of paddy annually, the shift could boost rural industrialisation, employment, and sustainable economic growth, she added.