Solvent Cleaning of Fouled Equipment With Nitrogen LEL Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing methods for removing deposits from refinery equipment, such as coke and contaminants, are inefficient, time-consuming, and pose safety hazards due to high levels of LEL vapors, often requiring costly and lengthy processes that can introduce catalyst poisons and increase operational risks.

Innovation Solution

A method involving a cleaning stream composed of a water-containing carrier fluid and solvent is introduced into the equipment, followed by a nitrogen stream to disaggregate and dissolve deposits, with a solvent composition that includes hydrocarbon solvents and oxygenated solvents to lower LEL vapors safely.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional methods are used to remove deposits from refinery equipment, then deposits can be removed, but the process is time-consuming and generates high levels of LEL vapors creating safety hazards

Engineering Contradiction:

ImprovesafetyVSAvoidturnaround time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The invention changes the chemical parameters of the cleaning process by using a water-containing carrier fluid with specific solvent compositions (5-50 volume% aromatic hydrocarbon solvent, 45-90 volume% oxygenated solvent) to alter how deposits are removed, reducing LEL vapor generation while maintaining effectiveness

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention converts the harmful effect of LEL vapor generation into a benefit by selecting solvents with low LEL characteristics. The oxygenated solvents and aromatic hydrocarbon solvents used have inherently lower LEL values, transforming a safety hazard into a safety advantage while still achieving deposit removal

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

2Quantity of substance

If traditional solvent compositions are used for cleaning, then deposits can be dissolved, but catalyst deactivation occurs due to introduction of catalyst poisons

Engineering Contradiction:

Improvedeposit removal effectivenessVSAvoidcatalyst performance

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

The invention changes the chemical composition parameters of the cleaning stream by specifying precise ranges of aromatic hydrocarbon solvents (5-50 volume%) and oxygenated solvents (45-90 volume%), selecting components that are effective against deposits but non-poisonous to catalysts

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The water-containing carrier fluid acts as an intermediary medium that delivers the solvent components to the deposits. This carrier system enables controlled dissolution of deposits while the water content helps prevent direct contact between certain solvent components and the catalyst, reducing poisoning risk

Inventive Principle:

Principle #24Intermediary (Mediator)

3Quantity of substance

If high concentrations of aromatic hydrocarbon solvents are used to dissolve deposits, then cleaning effectiveness improves, but LEL vapor levels increase creating safety hazards

Engineering Contradiction:

Improvedeposit dissolution efficiencyVSAvoidLEL vapor concentration

Core Design Contradiction:

Quantity of substanceVSObject-affected harmful factors

Solution Approach 1:

The invention optimizes the concentration parameter of aromatic hydrocarbon solvents to a specific range (5-50 volume%) rather than using high concentrations. This parameter optimization maintains sufficient cleaning effectiveness while limiting LEL vapor generation to safe levels

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention uses a composite solvent system combining aromatic hydrocarbon solvents with oxygenated solvents in specific proportions. This composite composition leverages the deposit-dissolving capability of aromatic hydrocarbons while the oxygenated solvents contribute to lower overall LEL vapor concentrations, achieving a balance between effectiveness and safety

Inventive Principle:

Principle #40Composite materials

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The method effectively removes deposits while reducing LEL vapors below safe levels, enhancing safety and efficiency by allowing quicker turnaround times and minimizing catalyst deactivation.

Implementation Method 1

a solvent effective to lower levels of LEL vapors below the LEL... contacting the deposits in the equipment with the cleaning stream... absorbing the deposits and/or disaggregating the deposits within the equipment

Methodology Applied

Scientific EffectSolvation: Solvation

Implementation Method 2

introducing a stream comprising nitrogen into the equipment after introducing the cleaning stream... lowering levels of LEL vapors below the LEL

Methodology Applied

Scientific EffectGas displacement:

Data Source

PatentUS20250387808A1Methods and systems for cleaning equipment with solvents

Publication Date: 2025.12.25 ZYMEFLOW INC

AI summary

A method for decontaminating fouled equipment including deposits includes (a) introducing a water-containing cleaning stream comprising a carrier fluid and a solvent into the equipment. In addition, the method includes (b) introducing a stream comprising nitrogen into the equipment after (a).