Membrane Silos in China: Innovations in Grain Storage

China is implementing new grain storage technologies, including the introduction of membrane silos in Sichuan Province. This was reported by Elevatorist.com.

This is reported by AgroReview

The new grain storage format involves the use of three-layer grain storage facilities equipped with an air membrane. The first industrial facilities have already begun operating, and research on new models is ongoing. These structures can hold up to 9,000 tons and can be constructed in just half an hour. They feature a high level of airtightness, which could significantly change approaches to food security. It is known that Chinese developers have signed contracts for dozens of similar facilities abroad.

Structure and Operating Principle of the Membrane Grain Storage

The membrane grain storage consists of three layers: the outer layer is an air membrane made of polyvinylidene fluoride (PVDF), one of the most durable modern polymers. The thickness of the membrane is 1 mm, and its weight is 4 tons. Manufacturers claim that it will last up to 30 years, requires no complex maintenance, and has self-cleaning properties.

The process of installing the silo begins with filling the outer layer with air on a specially prepared foundation. Construction then continues inside the structure. The second layer is insulating, made of polyurethane, which has very low thermal conductivity—four times lower than that of concrete and 100 times lower than that of steel—allowing for stable temperature maintenance even in hot seasons.

The third layer consists of reinforced concrete, which is applied to a reinforced frame, providing the structure with the ability to withstand significant pressure from the grain inside. Each storage facility is equipped with 350 sensors that measure temperature and humidity in real-time at various points within the volume.

Advantages and Challenges of the New Technology

According to Chinese sources, membrane silos have several significant advantages. Among them:

• environmental friendliness and speed of construction;
• high thermal insulation, reducing the need for grain cooling;
• airtightness, which protects against moisture and allows for the use of a nitrogen environment;
• reduced operating costs—by 30% compared to traditional elevators.

However, there are also drawbacks, particularly the high cost: one silo costs about 20 million yuan, which is 50% more expensive than conventional facilities. Research is also ongoing to assess how these structures withstand extreme weather conditions, including testing double membranes, emergency pressure systems, and additional protection.

The idea of using membranes in construction is not new; they are already used for pavilions, hangars, and stadiums. However, the Chinese have adapted this technology for grain storage, drawing on experiences from the coal industry.

In 2017, China Coal first introduced an inflatable membrane container for coal storage, and the requirements for grain storage turned out to be different. Therefore, the Central Research Institute of Grain, in collaboration with China Coal, spent several years adapting the project, testing various shapes, modeling loads, and building prototypes.

The pilot project began in 2021, and the first silo was erected in June 2022. According to one of the developers, “in terms of airtightness, this container exceeds the national Chinese standard by nine times.”

In 2023, the first four industrial containers, each with a capacity of 7,500 tons, were erected at the central reserve grain storage in Xinjing, standing 36 meters tall and 23 meters in diameter. Construction of new facilities with a capacity of 9,000 tons and a height of 33 meters with a diameter of 24 meters began in March 2025.

By the end of the year, five more similar storage facilities are planned to be put into operation in China, and contracts have been signed for 50 such elevators in Southeast Asian countries.