JPS59179131A - Safety managing method of adsorber of reactive organic solvent - Google Patents

Abstract

PURPOSE:To find out immediately the local temp. elevation in an activated carbon layer and to prevent an accident before it happens by detecting the CO concentration of an adsorbing tank using the activated carbon for reactive org. solvent recovery, and sprinkling water on the activated carbon by opening a control valve of water for fire fighting when the CO concentration exceeds a prescribed value. CONSTITUTION:In a reactive org. solvent-recovering equipment, a CO detecting, recording, alarming instrument CRA is provided in an activated carbon layer 1. When an abnormal reaction is generated at the local part 6 in the layer by reactive solvent such as ketone, CO is generated and the temp. is elevated at the same time. CO is transferred upwards and the CO concentration is increased at the upper part of the adsorbent layer. When the detected CO concentration exceeds the prescribed value, a control valve 5 of water for fire fighting is opened by a CO detecting signal and water sprinkling is carried out on the activated carbon layer 1.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for safely managing an absorption device for collection.

In solvent recovery using activated carbon, when using highly reactive solvents such as ketones, when these are adsorbed, they undergo catalytic action on the surface of the activated carbon, causing heat generation such as oxidative decomposition reactions. When such heat is accumulated in the activated carbon layer, the temperature rises, further promoting the reaction, and the mutual effect causes a rapid rise in temperature, which may cause the activated carbon to ignite.

When the solvent recovery device is in operation, bath agent-containing air and desorption vapor are flowing, so even if a reaction occurs, all of the heat is carried away by these, making it difficult for heat to accumulate in the h1 activated carbon layer.

Therefore, when the plant is shut down, there is almost no heat dissipation in the activated carbon layer, and there are many cases of temperature rise and ignition accidents due to heat accumulation.

Conventionally, to detect abnormalities within the activated carbon layer, the temperature within activated carbon No. 1 is detected using a detector TRA, as shown in Figure 1. requires a large number of detectors TRA as shown.

However, even if a large number of detectors TRA are installed, activated carbon has poor thermal conductivity, making it difficult to immediately detect localized heat generation.

In FIG. 1, 2 is an adsorption tank, 3 is a solvent (gas) inlet/outlet, 4 is a fire extinguishing water line, 5 is an automatic fire extinguishing equipment, and 6 is a local heat generation point.

The inventors of the present invention have conducted extensive research in order to discover the locally occurring abnormality described above at an early stage and to minimize the damage as much as possible, and have obtained the following knowledge. That is,
If reactive solvents such as ketones cause an abnormal reaction within the layer, Co will be generated even at relatively low temperatures (approximately 40°C or higher), and at the same time as CO is generated, there will be a rise in temperature and the co will move to the upper part. , eventually the Co concentration also increases in the upper part of the adsorption layer. Therefore, if this Co is detected, local abnormalities can be detected.
This can be detected more quickly than when temperature is detected.

The present invention was made based on these findings, and detects the carbon monoxide concentration in the tank in a reactive organic solvent absorption tank using activated carbon, and when the carbon monoxide concentration exceeds a predetermined value, The present invention relates to a safety management method for a reactive organic solvent absorption device, characterized in that a fire extinguishing water control valve is opened in response to a detection signal, and water is sprayed onto the activated carbon in the absorption tank.

In addition, conventionally, there is an example of detecting Co and/or CO2 as a way to know whether activated carbon has ignited.
o and/or CO2 are generated by the combustion of activated carbon itself with C+ % 02 → C0 C102 → COz 0 On the other hand, in the present invention, reactive solvents such as ketones do not reach the combustion zone, and reactive solvents such as ketones are This system detects CO that is decomposed and produced by the catalytic action of CO, and can detect a rise in temperature long before it reaches the ignition point, thereby preventing accidents. Figure 2 shows one embodiment of the present invention. 2 is a diagram showing an example. In FIG. 2, the same reference numerals as in FIG. 1 indicate the same parts as in FIG. 1, and CRA indicates a CO detection recording alarm device.

In addition, in the method of the present invention, the CO detection setting concentration can be set to different values during operation and stoppage, such as 1100 ppm during plant operation and 500 ppm when N is stopped. Furthermore, during plant shutdown, the solvent of adsorbed species 2 (
It is desirable to block at least the inlet/outlet (gas) inlet/outlet 3 to prevent a decrease in the detected concentration due to CO diffusion dilution.

[Brief explanation of drawings]

Sub-agent 1) Sub-agent Ryo Hagiwara -

Claims (1)

[Claims] In a reactive organic solvent absorption tank using activated carbon, the carbon monoxide concentration in the tank is detected, and when the carbon monoxide concentration exceeds a predetermined value, the detection signal opens the fire extinguishing water control valve, and the A safety control method for a reactive organic solvent absorption device characterized by sprinkling water on activated carbon.