| China is the world's largest food-producing countries and consuming countries, the total output of grain of about 500 million tons. According to statistics, China's grain harvest, threshing, drying, storage, transport, processing, consumption in the process of loss of up to about 18%, far exceeding the standard of 5% of the FAO regulations. Each of these losses due to climate reasons, the grain was too late dried or reach safe moisture causing mildew, sprouting and loss of food up to five percent, if the annual output of 500 million tons of grain, equivalent to 25 million tons of grain, if per person per day to eat 500g of food for 6.8 million people food for one year. This figure is alarming, to receive a hand grain losses to a minimum, in the sense that the grain drying mechanization than the mechanization of field operations is more important, it is an important guarantee for grain yield, harvest conditions.
The present. China's grain drying equipment are faced with rare opportunities for development: First, governments at all levels attach great importance to food production, especially the Central Committee in 2004 introduced a variety of measures to raise farmers' enthusiasm for growing grain, promulgated and implemented <Promotion of Agricultural Mechanization , the formation of economic support, price subsidies, tax incentives and other favorable policy environment; is an important part of the development of agricultural industrialization can not be separated from mechanical drying. Large grain, agricultural machinery, large, rural specialized cooperative economic organizations, and leading enterprises, and has strong aspirations and demands of the mechanical drying; three types of drying machines on the market, choose to promote the utility of new machinery and technology service support; combines rapid promotion and the mode of operation across a large number of grain to the need for timely, quick drying; five mechanical drying to avoid loss, prejudice to the defense of natural disasters, to prevent site Fanshai increase grain impurity and the road dried grain traffic safety, and can save valuable land resources, the importance of the development of grain drying equipment began to be widely recognized.
Constraints that exist in the grain drying equipment development process: First, the agricultural labor force continued to increase, the mouth of the country's 13 million people, 800 million in rural areas, the vast majority of surplus labor in rural, agricultural surplus labor pressure great, which will undoubtedly replace the labor grain The growth of the drying equipment have a reverse impact; the slow growth of farmers 'income, this will directly affect the purchasing power of farmers' agricultural; increase in agricultural imports. Exports, especially in the addition of the WTO; agricultural support policies in place. Should also be soberly aware that the unfavorable factors in the development process of grain drying equipment: First, grain drying equipment investment; investment recovery period is longer; farmers' low level of industrial management, the social organization of production services systems and mechanisms yet to be formed; four impurity rate of the raw grain, uneven moisture, the higher the quality of dry mechanical properties. Reasonable selection of supporting
Suitable for China in small multi-function development, a variety of models of the heat source to consider the use of business models and cross flow of operations for the development of direction, making it a simple structure, low cost, high thermal efficiency, high productivity, with good promotion prospects.
1) heat source options. Try to choose a variety of energy sources drying machine according to the local energy conditions, such as electricity, diesel, kerosene, solar and straw. To increase adaptability. Three kinds of relatively common greenhouse solar drying system close to natural dry state, dried food tasty, does not contaminate the food and the environment, low cost; system investment by the impacts of climate change, applies only to light a long time areas.
2) according to the function selection. Of a machine, in addition to dry food, but also the drying such as rapeseed, Chinese herbs, edible fungus, starch and other variety of agricultural products, with sterilization, disinfection and other multi-functional; dryer should have a fully automatic computer control system, water testing, drying rate, grain temperature, grain volume, the outside temperature changes, amendments to the drying temperature, combustion temperature, timed shutdown, scheduled water shutdown and other safety protection controlled by a computer, which effective control of the grain quality, taste, Crackle, energy-saving drop consumption has an important role.
3) capacity model selection. Model size by the conditions for agricultural production, the scale of the decision. China's farmers scattered, small scale, small dryer with greater adaptability, can be developed to take 3-6km. , 2t small dryer installed capacity to facilitate the purchase of the majority of farmers; 6t more large and medium-sized machinery is generally bought the operation from the village, township agricultural service organizations.
Promote the mechanization of the dryer to speed up the food production rush in the harvest, promote operating efficiency and operating to improve the quality of the food production chain, and has played a "grab farming, anti-disaster, promoting high yield" of the results. China's grain drying equipment status, combined with the vast rural market demand, experts pointed out that the development of China's grain drying equipment will present six development trends.
Grain drying equipment
First, speed up the grain drying equipment production enterprise restructuring, reorganization, transformation, solve manufacturing enterprises, small scale production, high production costs, low economic efficiency, the production concentration and specialization of grain drying equipment has improved greatly, and promote domestic and international market development and product after-sales service system to truly create a strong enterprise technology innovation base, driven by the improvement of industry-wide technology, quality, service and competitiveness.
The second is to design high-moisture grain once down to the equipment of the safety standards. In this regard there are two ways you can choose: one is the traditional single dry mode, and the second is the use of combined drying method, the drying unit of the upcoming two kinds of drying methods to synthesize a new drying process from the current world grain drying technology development, this is a trend; design high-performance grain flash dryer.
Can high temperatures, rapid processing of large quantities of high-moisture grain.
Fourth, the application of advanced control technology, the drying process to the development of automatic or semi-automatic direction.
Fifth, the development of grain production capacity of the dryer toward the poles. In view of this situation, the product manufacturers need to develop a processing capacity of 20 tons - 30 tons per hour, large-scale equipment, usually purchased from the village, township agricultural service organizations operate around the business situation, the establishment of professional drying institutions. Also to the development of small-scale, multi-functional direction to facilitate the majority of farmers and geographically dispersed farmers to buy.
The development of the dryer should pay attention to energy conservation and comprehensive utilization of energy, give full play to the energy characteristics of the different regions, such as the use of joint heating methods, transplantation heat pump and heat pipe technology, the development of solar dryers; but also the development of automatic control technology of the dryer In addition, with the human importance of environmental protection, improve the dryer's environmental protection measures to reduce dust and exhaust leaks, in order to ensure the realization of the optimal operating conditions; will also be studied in depth direction.