Multichannel carbon dioxide concentration automatic surveying device of grain piles in grain bin

Abstract

A Multichannel carbon dioxide concentration automatic surveying device of grain piles in a grain bin comprises a plurality of gas pipelines which are installed in a grain pile in a grain bin and are connected with a gas surveying device which is driven by a stepping motor and composed of a fixed plate and a rotary plate. Air inlets which are connected with corresponding gas pipelines are uniformly arranged on the periphery of the fixed plate. An air outlet which is connected with an air suction port of a getter pump through an exit end valve is disposed at 1 / 2 radius of the fixed plate. A positioning contact is respectively arranged at the rim of each air outlet on the combination side of the fixed plate and the rotary plate. A ring slot and a radial rectangular gas vent are processed at 1 / 2 radius of the combination side of the rotary plate and the fixed plate, wherein the inner end of the gas vent communicates with the ring slot and the outer end of the gas vent extends towards the edge to the position of the air inlet arranged on the fixed plate. A positioning contact is arranged at the rim of the outer end of the radial rectangular gas vent. An exhaust port of the getter pump is connected with a carbon dioxide sensor through a three-way gas pipe. A remote control system is respectively electrically connected with corresponding control ends of the stepping motor used for driving the rotary plate, the getter pump, the carbon dioxide sensor and a display through corresponding electric control circuits and signal lines.

Description

technical field [0001] The invention belongs to the technical field of grain storage safety monitoring, and in particular relates to a device capable of automatically inspecting the carbon dioxide concentration of a large number of preset monitoring points in grain heaps, so as to remotely monitor pests and molds in grain heaps outside the grain heaps Techniques for Hazardous Activities. Background technique [0002] Insect and mold control of stored grain is the main task of the storage industry. Insect mold activity not only consumes the quantity of grain, causes deterioration of grain quality, but also may cause serious food safety problems. It is well known that aflatoxins with strong toxicity and carcinogenicity may be produced by the growth and metabolism of molds such as Aspergillus flavus in grains. Only by warning before these molds produce toxins and taking effective control measures can food toxin pollution be prevented. occur. Therefore, the monitoring of ins...

AI Technical Summary

Problems solved by technology

This method can realize remote control detection outside the warehouse, which makes up for the shortcomings of the first two types of methods, but still has its own defects that are difficult to overcome: (1) The system structure is complex and difficult to maintain

For the common granary of 30×50 meters in the granary, the effective monitoring points are usually set at a plane interval of 4 meters, and the space is divided into 3 layers. A total of nearly 300 points are required for each warehouse (increasing the density can further improve the detection effect). It is necessary to build a large number of solenoid valve groups. The system is bulky and it is difficult to find a suitable space for installation in the granary. a lot

(2) The purchase cost of the solenoid valve group is very high

The monitoring system needs to be installed in the granary (the gas pipeline installed outside the granary is too long), and the dust environment in the granary or the fumigant gas of phosphine are all explosion media, so expensive explosion-proof solenoid valves must be selected, and the cost of the entire system is very high. high

(3) The volume of the gas collection main pipe is large, which affects the detection efficiency and accuracy

Each detection system generally only has one carbon dioxide sensor (a carbon dioxide sensor for each monitoring point is not only costly, but also reduces the monitoring effect, because this monitoring method mainly finds out the change of carbon dioxide concentration by comparing the changes of carbon dioxide concentration at each monitoring point Larger points will be further checked and confirmed for pest and mildew hazards, but the carbon dioxide sensor itself has detection bias, and the carbon dioxide sensor installed at each monitoring point in the granary will affect the accurate comparison of each monitoring point), this method requires all solenoid valve gas The output end is collected into a main pipe, and the gas collection pipe connecting hundreds of gas pipelines is relatively large in volume. When testing each detection point, the gas in the gas collection pipe needs to be replaced first, not only cannot guarantee whether the gas is completely Replacement, and it takes a long time to change the air, the sampling point has a large inhalation volume, especially the inhalation of a large amount of gas will change the concentration and nature of the gas at the detection point itself, affecting the accuracy and reliability of the detection

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