The rice processing equipment technology is divided into three stages: rice pre-cleaning section, hulling separation section, rice milling and finished product finishing section.

The technological process of the rice cleaning section is: rice→primary cleaning→removal of impurities (sand, metal, barnyard grains, etc.)→clean rice.

The process flow of the paddy separation section is: paddy cleaning → paddy hulling → rice husk separation → paddy and roughness separation → cleaning and roughness.

The process flow of rice milling and finished product finishing section is: rough rice → primary whitening → secondary fine milling → grading → cool rice → white rice grading → polishing → white rice grading → secondary polishing → roller selection → Color sorting → rice preparation → measuring and packaging → finished product storage.

The main components of rice processing equipment are: grain cleaning machine, destoning machine, rice huller, separator, rice mill, grader, rice color sorter, polishing machine, conveyor, etc. 1. Types and characteristics of factory process layout

1.1 Shed layout

The shed layout method is mainly used for process design with a processing capacity of less than 100 t/d, and is mostly used in 30 t/ d, 50 t/d, 70 t/d and other processing plants have short process flow lines, simple layout, and low overall investment. It is suitable for use in small processing plants, supporting emergency processing in grain depots, or in complete sets of units for export.

The architectural design mainly adopts a large-span door steel structure with a column-free design in the middle, which can maximize the use of space in the shed to arrange equipment. The equipment platform can be made of concrete or steel structure. The equipment is laid out in a "line" shape and is short in length, making it easy to operate and manage. The typical layout is shown in Figure 1.

1.2 Patio layout

The patio layout method mainly uses the equipment platform and civil construction space in the workshop to form a patio in the workshop, which is conducive to lighting and makes the workshop spacious and bright. This layout method is mainly used for process design with a processing capacity of 100 to 300 t/d. It can be arranged in a single line or a double line according to the user's usage habits and regional characteristics. The double-line layout has a certain degree of flexibility and can be flexibly arranged according to market needs. It is suitable for use in medium-sized processing plants.

There are two main design forms:

(1) Design using steel structure outer shed with concrete platform, mainly using long-span steel structure column-free design, using concrete or steel structure platform Arrange equipment. The advantage is that it adopts steel structure construction, the installation cycle is short, and the investment is relatively economical. The disadvantage is that the overall image of the workshop is slightly poor. Private rice mills often adopt this form, and a typical example is shown in Figure 2.

(2) Adopt concrete building structure with steel structure hanging design, and use partial steel platform hanging to save civil construction costs. The advantage is that concrete building design can greatly increase the service life of the workshop and reduce workshop noise, enhance the overall image of the company, and ensure food safety. The disadvantage is that the construction period is longer and the overall investment is slightly higher. A typical example is shown in Figure 3. 1.3 Flat layout

With the scale development of enterprises, equipping with visiting corridors, enhancing brand image, and ensuring food safety have increasingly become the focus of rice processing enterprises, and the workshop design form has also changed accordingly. This led to the development of the rice factory design form with a tiled layout. The main building plan is a three-layer concrete structure layout. The first layer is the base layer of the lifting equipment, the second layer is the host equipment layer, and the third layer is the buffer and lifting equipment head layer. The layered arrangement realizes partition management of various types of equipment. .

In the tiled layout, the visiting corridors and host equipment are concentrated on the second floor, which is on the same floor as the control room, which facilitates equipment management and maintenance. Its production range is between 100 and 1,000 t/d. Subject to the limitation of single machine output, production lines of 100 to 220 t/d can be arranged in a single line, and production lines larger than 220 t/d need to be arranged in parallel with double lines or multiple lines. The tiled layout uses a multi-layered concrete structure. The advantage is that the layout of each layer has a clear division of labor, which facilitates the isolation of production areas and visiting areas. The disadvantage is that the civil construction cost is relatively high. However, due to its clear functional divisions, complete facilities and meeting food safety requirements, it has increasingly become the first choice of users.

The typical tiled floor plan and site diagram are shown in Figure 4 and Figure 5. Generally, there are four major areas: visiting corridor, equipment area, dust removal area and management area. The equipment area can be arranged according to the workshop output. Single or multiple lines are arranged in parallel. The visiting corridor is isolated from the main equipment layer by a glass curtain wall; the dust removal area and the equipment area are fully separated by solid walls; the management area is generally set up facing the main equipment area. 1.4 High-rise layout

The tiled layout takes into account that the operation of main machines such as rice machines and polishing machines requires manual operation. The main machines are generally arranged on the same floor to facilitate operation and reduce the number of personnel. However, with economic development, in economically developed areas, land has increasingly become a scarce resource. The flat layout covers a large area and the problem of low land utilization has become increasingly apparent.

With the development and application of single-machine processing equipment in China in recent years, especially multi-unit vertical rice machines, the degree of automation has also increased, and the design method of high-rise layout has increasingly become a trend in the design of rice factories in developed areas. The high-rise layout makes full use of height space development, and the equipment layout is unfolded layer by layer, and the equipment that still needs to be operated by personnel is concentrated on the first floor as much as possible, as shown in Figure 6. It not only solves the problem of large floor space occupied by the tiled layout, but also ensures the convenience of operation.

The disadvantage of this layout is that it puts forward higher requirements for rice factory management and automatic control equipment. It requires enterprises to increase investment in automatic control equipment and use temperature, humidity and other sensing parameters to guide production and ensure Product quality stability.