Grain Storage Technology Upgraded: Sinograin Provides Society with Reassuring Grain Sources
“As economic development enters the new normal, people's consumer demand has shifted from simply eating their fill in the past to eating well, and from eating abundantly and deliciously to focusing on quality, safety and health. Food safety 'on the tip of the tongue' is attracting more and more attention.” The head of the Sinograin General Office told this writer, “By promoting green technology for grain storage, Sinograin is upgrading the management of the world's granaries and providing society with high-quality, reassuring grain sources.”
Full Coverage of the “Four-in-One” Grain Storage Technology
At the Zhengzhou Directly Subordinate Depot, the person in charge of the depot pointed to a flat warehouse behind him and said: “This warehouse was built in 2000 and can hold more than 4,000 tons of grain, with a grain pile 6 meters deep. Although a large granary has a large capacity per warehouse, the grain layer is high, the grain pile environment is complex, heat and moisture easily migrate, and pests easily spread, increasing the risks of heating, deterioration, condensation, mildew and pest damage in the grain pile.”
Since the beginning of the new century, China's grain storage scale has continued to increase, and tall flat warehouses and squat silos have become the mainstream warehouse types. Traditional methods and single technologies find it difficult to achieve large-scale, long-term safe grain storage in tall, large granaries. For this reason, Sinograin Corporation, together with the National Grain Science Research Institute and many other units, jointly developed a completely new technology system suited to China's grain storage needs in the new era.
The working principle of the “Four-in-One” technology is: with standard air network layout and a unified computer management system, it organically combines four technologies - grain condition monitoring, mechanical ventilation, circulation fumigation and grain cooling - to solve the main difficulties of safe grain storage in tall flat warehouses and squat silos. By placing hundreds of temperature sensors in layers within the grain pile of each warehouse, real-time detection and precise analysis of grain conditions are achieved; through intelligent computer control, mechanical ventilation is carried out on stored grain, eliminating condensation and mildew in the grain pile; by installing pipes in the middle of the granary, automated, low-dose, explosion-proof circulation fumigation is carried out, effectively killing resistant pests; and by using variable-frequency, adjustable-airflow high-efficiency grain coolers, the grain pile is rapidly cooled.
Ten years ago, in 2005, the comprehensive application rate of the “Four-in-One” grain storage technology in the Sinograin system had already reached 100%, completely eliminating “aged grain”, and the suitability-for-storage rate rose steadily from 70% to more than 95%. Because of its enormous social and ecological benefits, the research, development and integrated innovation project of the “Four-in-One” grain reserve technology won the 2010 “National Science and Technology Progress First Prize”.
Integrated Temperature-Controlled Grain Storage Shows Results
At the Wenzhou Directly Subordinate Depot of the Central Grain Reserve, this writer saw that air conditioners had been installed in all the granaries. According to the depot's custodian, “In summer, based on grain temperature monitoring data, supplementary cooling measures such as air-conditioning temperature control are automatically started, keeping the average grain temperature of stored grain below 20 and the average temperature of the upper layer below 25, ensuring safe storage of grain through the summer.”
Paddy rice is a grain variety that does not store well, and the problem of rapid quality change is especially prominent in southern regions. For this reason, Sinograin actively explored reasonable combinations of technology, processes and equipment, and was the first in the industry to formulate the “Technical Regulations for Temperature-Controlled Storage of Paddy Rice”, proposing the temperature-controlled storage technical route of “ventilate in autumn and winter to lower the base grain temperature; insulate in spring to delay the rise in grain temperature; remove heat in summer and supplement cold sources in a timely manner”, and separately proposed different seasonal temperature-control requirements for paddy rice storage in the South China high-temperature, high-humidity grain storage ecological zone, the East China hot and humid grain storage ecological zone, and the Yunnan-Guizhou Plateau region.
According to reports, the comprehensive benefits of temperature-controlled grain storage are high. Generally speaking, the cost of integrated temperature-controlled storage per ton of paddy rice is about 4 yuan per year, including equipment depreciation and electricity charges, but because of its good quality and popularity, its ex-warehouse selling price is considerably higher than that of ordinary paddy rice, not only achieving good grain at a good price, but also providing society with higher-quality grain.
In addition, Sinograin uses the favorable climatic conditions of the “Three-North Region” to promote low-temperature (near-low-temperature) grain storage technology locally, ensuring that the average temperature of the grain pile is controlled within the target range of low temperature (below 15) and near-low temperature (below 20). At present, the proportion of low-temperature (near-low-temperature) grain storage in Sinograin's “Three-North Region” has reached more than 80%.
Nitrogen Grain Storage at International Leading Level
The Nanning Directly Subordinate Depot is located in a high-temperature, high-humidity region of the south, and its stored grain varieties are mainly paddy rice, making grain preservation difficult. But it is precisely this grain depot that has achieved “zero fumigation, zero deterioration, zero pest damage” for three consecutive years, widely praised in the industry, thanks to a secret weapon of the depot - nitrogen grain storage technology.
The depot's custodian turned on the nitrogen generator: “The nitrogen generator separates nitrogen from the air and fills the grain pile with high-concentration nitrogen, keeping the nitrogen concentration in the grain pile above 96%. In this way, pests and mold cannot grow or reproduce, achieving physical control of insects and mold, thus eliminating the use of chemical fumigation to kill insects.” It is understood that using chemical agents to control stored-grain pests is currently the internationally common practice. However, the problems arising from this have gradually attracted attention, such as increased pesticide resistance in stored-grain pests and potential harm to the health of operators. “Nitrogen grain storage technology separates nitrogen from the air; the process does not pollute the environment or harm operators, and more importantly, it avoids contact between grain and chemicals. It is a purely green stored-grain pest control technology.”
The nitrogen grain storage warehouse is sealed on five sides, so after nitrogen is injected it will not escape, and the entire grain pile is like being placed in an oversized “fresh-keeping bag”. According to reports: “In addition to controlling pests, the nitrogen storage environment can also inhibit the grain's own respiratory metabolism. On the one hand, it reduces heat from grain respiration and ensures safe storage; on the other hand, it also reduces the loss of dry matter in the grain, achieving a fresh-keeping effect, and the quality of stored grain is greatly improved.”
“Food is the first necessity of the people, and safety comes first in food. Facing the new normal, Sinograin will continue to adhere to the direction of green development, comprehensively upgrade the management model of national reserve grain, serve as a representative of the industry's advanced productive forces, and make new contributions to national food security and sustained, healthy economic and social development.” A relevant person in charge of Sinograin said. It is understood that Sinograin Corporation has studied and formulated the “2015-2019 Warehouse Science and Technology Development Plan”, planning to invest about 3 billion yuan over the next 5 years, focusing on promoting 7 green, low-carbon advanced grain storage technologies and equipment (namely integrated temperature control, nitrogen controlled-atmosphere storage, intelligent ventilation, intelligent drying, quality preservation and loss reduction, intelligent grading at purchase, and cleaning and impurity removal technology), building green, energy-saving, efficient and safe grain storage technology systems for different ecological regions and different varieties, boosting quality preservation, loss reduction and consumption reduction in grain storage, striving to control grain storage loss within 1.2% in 2015 and within 1% by 2016, and building the reserve well as an “intangible grain field”.