Abnormal temperature detection for fixed bed reactors

Abstract

Systems and methods are provided for detecting abnormal temperature conditions within a fixed bed reactor. In a fixed bed reactor, a hydrocarbon (or hydrocarbon-like) feedstock can be exposed to one or more types of catalyst particles at elevated temperatures and/or pressures. In addition to the one or more types of catalyst particles, a plurality of temperature-sensor structures can be included in a catalyst bed and/or a coating including one or more temperature-sensor structures can be provided on an interior wall or other interior surface in the reactor. The temperature-sensor structures can have a threshold temperature at which the temperature-sensor structure changes to allow introduction and/or release of a detectable substance.

1 - 9 . (canceled) 
     
     
         10 . A method for processing a feed in a fixed bed reactor, comprising: exposing a hydrocarbon-like feed to a catalyst in a fixed catalyst bed in a reactor under fixed bed processing conditions to form a reactor effluent, the fixed bed processing conditions comprising an average catalyst bed temperature for the fixed catalyst bed, the reactor further comprising one or more temperature-sensor structures, the one or more temperature-sensor structures having a threshold temperature; and detecting a detectable substance in the reactor effluent, the detectable substance being introduced into the reactor effluent by at least one of the one or more temperature-sensor structures, wherein:
 a) when the detectable substance is detectable prior to exposing a temperature-sensor structure to a threshold temperature, the amount of detectable substance detected in the reactor effluent is at least about 1% greater than an average amount detected in the reactor effluent at the average catalyst bed temperature; or   b) when the detectable substance is not detectable prior to exposing a temperature-sensor structure to a threshold temperature, the amount of detectable substance in the reactor effluent is greater than the detection limit for the detectable substance.   
     
     
         11 . The method of  claim 10 , wherein the amount of detectable substance detected in the reactor effluent is at least about 10 times greater than the average amount detected at the average catalyst bed temperature. 
     
     
         12 . The method of  claim 10 , wherein the one or more temperature-sensor structures have a first rate of introducing the detectable substance into the reactor at a temperature below the threshold temperature and a second rate of introducing the detectable substance at a temperature above the threshold temperature, the second introduction rate being at least about 5 times the first introduction rate. 
     
     
         13 . The method of  claim 10 , wherein the average bed temperature is at least about 20° C. lower than the threshold temperature. 
     
     
         14 . The method of  claim 10 , wherein the hydrocarbon-like feed comprises a petroleum feed, a renewable feed, a refinery feed, a chemicals feed, or a combination thereof. 
     
     
         15 . The method of  claim 10 , wherein the one or more temperature-sensor structures comprise temperature-sensor particles. 
     
     
         16 . The method of  claim 15 , wherein the temperature-sensor particles are distributed randomly in the catalyst bed. 
     
     
         17 . The method of  claim 10 , wherein the one or more temperature-sensor structures comprise at least a first temperature-sensor structure having a first threshold temperature and a second temperature-sensor structure having a second threshold temperature. 
     
     
         18 . The method of  claim 17 , wherein the first temperature-sensor structure introduces a first detectable substance into the reactor, the second temperature-sensor structure introduces a second detectable substance into the reactor, and the first detectable substance is different from the second detectable substance. 
     
     
         19 . The method of  claim 10 , wherein the reactor comprises a coating on an interior surface, the coating being at least one of the one or more temperature-sensor structures, the coating comprising one or more temperature-sensor particles, or a combination thereof. 
     
     
         20 . The method of  claim 10 , wherein, when the detectable substance is not detectable prior to exposing a temperature-sensor structure to a threshold temperature, the amount of detectable substance detected in the reactor effluent is about 1 ppb to about 1000 ppm by weight.