China is the most populous country in the world, and food production security is always the top priority of the country. As the largest grain producer and consumer in the world, China has taken a series of effective measures to ensure the sustainable development of grain production. From 2004 to 2004, grain production increased for eight consecutive years. In 2011, the grain output of Quan reached 1.1424 trillion tons (571 million tons), creating a new record of domestic food production. In the face of several years of harvest, while cherishing the hard-won good situation of agricultural development, we are also considering how to reduce the loss of food due to weather changes after harvest, such as drying production. According to statistics of relevant departments, the impact of climate change caused food losses, such as mildew and germination, up to 5%. If 500 million tons of grain are produced annually, the equivalent of 25 million tons of grain will be broken. Therefore, in this sense, developing grain LPG high speed centrifugal spray dryer is imperative.

Development of LPG high speed centrifugal spray dryer

I. The concept of LPG high speed centrifugal spray dryer.

Grain drying is an important link in agricultural production, an important link in agricultural production, and an important part of the overall mechanization of grain production. Using LPG high speed centrifugal spray dryer technology as the main means, and applying corresponding technical measures, artificially controlling temperature, humidity and other factors, without reducing the grain quality, the water content in the grain is reduced, and the national safe storage standard drying technology is applied.

Two. Classification and advantages of LPG high speed centrifugal spray dryer

Classification of LPG high speed centrifugal spray dryer for grain

According to the heating mode, the dryer can be divided into flow type, conduction type, radiation type and dielectric type.

(1) Flow dryer, also known as direct dryer, uses hot drying medium to contact wet materials directly, transfers heat through convection, and takes away the steam generated;

(2) Conductive dryer, also known as indirect dryer, uses conduction mode, transfers heat to wet materials through heat transfer mode, and through metal baffles, produces water vapor which can be vacuum suction and a small amount of purging gas or low-temperature condensation method set on the surface of a single ventilated condenser. The dryer does not use drying medium, has high thermal efficiency and is free from pollution. However, the drying capacity is limited by the heat transfer area of the metal wall, and its structure is complex. It is often operated in a vacuum.

(3) Radiation dryer uses various radiators to emit electromagnetic waves in a certain wavelength range, which are selectively absorbed by wet substances and then converted into heat drying.

(4) The medium dryer is used for drying the internal thermal effect of wet materials by high-frequency electric field.

The advantages of the above dryers are as follows:

With high-performance evaporator, the heat transfer area is large, the heat transfer temperature is low, and the outlet temperature of the evaporator is more stable.

1. High-efficiency gas-water separation structure, high efficiency of oil-water separation.

2. the dryer can be divided into fixed bed type, stirring type, spray type, and compound type according to the movement mode of wet material.

3. according to the structure, the dryer can be divided into the van, drier, dryer, roller conveyor, vertical dryer, mechanically stirred dryer, rotary dryer, fluidized bed dryer, pneumatic dryer, vibrating dryer, spray dryer and combined dryer.

4. development trend of LPG high speed centrifugal spray dryer abroad

Foreign grain high-speed centrifugal spray dryer research began in the 1940s, in 50s and 60s, developed countries basically realized the grain LPG high speed centrifugal spray dryer, the 60s, and 70s grain drying automation, in 70s and 70s grain drying to high efficiency, high quality, energy-saving, reduce costs, computer control direction, 90 drying equipment has been Realizing serialization and standardization. In recent years, great progress has been made in computer simulation of the grain drying process. Traditional software and proprietary software have played a very important role in the design of grain dryer and the improvement of product quality.

Japan is one of the world's LPG high speed centrifugal spray dryer Zui. Its grain drying machinery industry has a long history and strong R&D strength. Japan's grain LPG high speed centrifugal spray dryer started in the late 1950s, through the continuous progress of science and technology, especially the government support policy, its technology level is in the world-leading Xian status, grain LPG high speed centrifugal spray dryer 92%.

At present, Japan, Korea, Taiwan, and other countries or regions which widely grow rice actively promote the development of rice conditioning and drying equipment. In 2009, the number of rice conditioning and drying equipment in Japan was about 25,000. Manufacturers of rice conditioning and drying machineries, such as Yamamoto, Bamboo, Shizuoka, and Gold of Japan, Korea International, Hancheng, Xinxing, and Taiwan, serve as basic models for rice drying.