Process For Removing Hydrocarbons And Noxious Gasses From Reactors And Media-Packed Equipment

Abstract

A process for quickly removing hydrocarbon contaminants and noxious gases in a safe and effective manner from catalytic reactors, other media packed process vessels and associated equipment in the vapor phase without using steam. The cleaning agent contains one or more solvents, such as terpenes or other organic solvents. The cleaning agent is injected into contaminated equipment, along with a carrier gas, in the form of a cleaning vapor.

1 . A method for removing a contaminant from a process system having a catalyst, comprising the steps of:
 (i) providing a carrier gas source;   (ii) providing a non-aqueous solvent source;   (iii) delivering the carrier gas and the non-aqueous solvent from their respective sources to the process system having said catalyst; and   (iv) removing said contaminant out of said system, wherein substantial amount of said contaminant is dissolved in said solvent in a vapor or liquid state as it is being removed from said system,   wherein the carrier gas is at least one member selected from the group consisting of nitrogen and hydrogen.   
     
     
         2 . A method for removing a contaminant from a process system having a catalyst, comprising the steps of:
 (i) draining the system of hydrocarbon feedstock without removing said catalyst,   (ii) providing a carrier gas source;   (iii) providing a non-aqueous solvent source;   (iv) delivering the carrier gas and the non-aqueous solvent from their respective sources to the process system; and   (v) removing said contaminant out of said system, wherein substantial amount of said contaminant is dissolved in said solvent in a vapor or liquid state as it is being removed from said system,   wherein the carrier gas is at least one member selected from the group consisting of nitrogen and hydrogen.   
     
     
         3 . The method of  claim 1 , wherein both the carrier gas and the solvent make contact with the catalyst in the process system in step (iii) thereby rendering the catalyst substantially dry. 
     
     
         4 . The method of  claim 1 , wherein the carrier gas delivered to the system is substantially free of water. 
     
     
         5 . The method of  claim 1 , wherein the solvent is delivered to the system as a vapor. 
     
     
         6 . The method of  claim 1 , wherein the process system is selected from the group consisting of a reactor, an absorbent chamber containing a molecular sieve, and a pressure vessel. 
     
     
         7 . The method of  claim 6 , wherein the process system contains a medium comprising at least one material selected the group consisting of a support material, a molecular sieve and a desiccant. 
     
     
         8 . The method of  claim 1 , wherein the process system comprises a reactor circuit used in a refining hydrotreating process and associated equipment. 
     
     
         9 . The method of  claim 1 , wherein said associated equipment is at least one member selected from the group consisting of a shell and tube exchanger, a fired heater, a distillation tower, and an interconnecting piping. 
     
     
         10 . The method of  claim 1 , wherein the contaminant is an organic contaminant. 
     
     
         11 . The method of  claim 10 , wherein said organic contaminant comprises at least one member selected from the group consisting of crude oil and its derivatives, hydrocarbons and noxious gases. 
     
     
         12 . The method of  claim 11 , wherein said organic contaminant is a noxious gas, said noxious gas being at least one member selected from the group consisting of hydrogen sulfide, benzene, carbon monoxide, and a light end hydrocarbon, said light end hydrocarbon being capable of resulting in a positive reading when tested for the Lower Explosive Limit (or “LEL”). 
     
     
         13 . The method of  claim 1 , wherein the temperature of the equipment in the system is adjusted to a range of between 225° F. and 400° F. prior to the introduction of the solvent. 
     
     
         14 . The method of  claim 1 , wherein the solvent is introduced into the carrier gas by connecting the gas and solvent sources. 
     
     
         15 . The method of  claim 1 , wherein the solvent is a non-polar organic solvent. 
     
     
         16 . The method of  claim 1 , wherein the solvent is a C1-C50 hydrocarbon. 
     
     
         17 . The method of  claim 1 , wherein the solvent comprises at least one member selected from the group consisting of aliphatic, paraffinic, isoparaffinic, aromatic, naphthenic, olefinic, diene, terpene, polymeric or halogenated hydrocarbon, and wherein the solvent is a naturally occurring, synthetic or processed organic solvent. 
     
     
         18 . The method of  claim 1 , wherein the solvent is a processed solvent selected from the group consisting of an aromatic solvent, virgin naphtha, terpene and hexane. 
     
     
         19 . The method of  claim 1 , wherein the solvent is delivered to the system as a vapor and the volumetric or weight ratio of said solvent vapor and the carrier gas is accurately controlled. 
     
     
         20 . The method of  claim 19 , wherein the weight ratio between said solvent vapor and said carrier gas is in the range of about 0.1 to about 6. 
     
     
         21 . The method of  claim 19 , wherein the weight ratio between said solvent vapor and said carrier gas is in the range of about 2 to about 4.