| In recent years,the planting area and annual yield of potatoes have increased,postharvest potato storage has become the key to the development of potato industry in order to prolong the processing cycle of potatoes,ensure the quality of potatoes and reduce the diseases during the storage period.At present,there are many potato storage methods,such as ventilation storage and cold storage,but there are some problems such as small storage capacity,low automation,improper management and poor storage effect.This paper relies on the potato storage house built by Shandong Star Agricultural Equipment Co.,Ltd.to study,focusing on the design of ventilation system and environmental control system.The main research contents are as follows:(1)The ventilation system of potato storage is studied in this paper.The ventilation system uses the air channel and strip channel setting on one side of the storage to realize the ventilation form of supplying air from bottom to top,and determines the position of the air inlet.The size of air inlet is determined according to the ventilation capacity of potato storage.In order to prevent the potato from being damaged by air over freezing,a mixed air bin is added to improve the air temperature.At the same time,the relevant parameters of fan and humidification device are calculated to make the ventilation system more reasonable and ensure the regulation effect of the regulation system.(2)According to potato storage technology,Siemens PLCS7-200 is used as the control core to design environmental control system for potato storage.By analyzing the general requirements of system regulation,the design of hardware system and software system is given,and the environmental control system is established.The system has 8 temperature measuring points and 2 humidity measuring points,and uses temperature sensor,humidity sensor and CO2 concentration sensor to detect the environmental parameters in the storage room in real time.When the requirements set by the system cannot be met,the temperature,relative humidity and CO2 concentration of the potato storage environment,which can be controlled by controlling the electric push rod for in and out of the air window,fan,compressor unit and humidification device,so that the temperature,humidity and CO2 concentration of the storage environment can meet the requirements of potato storage.(3)The environmental control system of potato storage was tested based on the above research.In the experiment,the accuracy test of distribution measuring points,the temperature test of callus period,the storage period test and the storage effect test of potato were carried out respectively.The test results showed that the temperature error of each measuring point was-0.3?0.3?,the temperature range of each measuring point was 0.6?,the temperature of the measuring point and the real temperature kept basically the same,which basically met the regulation requirements of the system,and the problem of uneven temperature distribution is improved to a certain extent.In the control test,the temperature in storehouse was within the allowable range of the set value,while the temperature outside the storehouse had little influence on the temperature in the storehouse,and the relative humidity was within the reasonable range,CO2 concentration was also within the system setting range,so it could better improve the storage environment of potato.In the experiment of potato storage effect,the experiment of potato storage effect was carried out,which the weight loss rate,soluble solids and color of potato were mainly detected.In the experiment,the weight loss rate of potato was 3.7% after 120 days storage,and the content of soluble solid changed within a reasonable range,which was basically stable.Through the observation of color,potatoes kept a good water and luster,and obtained a good storage effect.It is of great significance for accelerating the postnatal callus,prolonging the storage period and ensuring the quality of potatoes during the storage period. |
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