Bottle Brush Polymers for Silica Scale Inhibition

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Silica and silicate scales continue to be a major challenge in aqueous systems despite existing scale inhibitors, leading to costly process downtime and inefficient scale removal methods.

Innovation Solution

The use of bottle brush polymers, specifically copolymers composed of anionic monomers, polyoxoalkylene-containing monomers, and nonionic monomers, such as acrylic acid, methacrylic acid, and polyethylene glycol methyl ether methacrylate, to inhibit silica scale formation in aqueous systems by retarding deposition and maintaining silica in a dispersed state.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional scale inhibitors are used, then silica scale formation is partially controlled, but complete inhibition is not achieved leading to process downtime

Engineering Contradiction:

Improvesilica scale inhibition effectivenessVSAvoidprocess downtime

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent changes the chemical parameters of scale inhibitors by using bottle brush polymers with specific architectures containing polyoxaalkylene-containing monomers (5-50 mole%), anionic monomers (10-40 mole%), and nonionic monomers (5-30 mole%). This specific compositional parameter change achieves superior silica scale inhibition compared to conventional linear polymers, preventing process downtime

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention creates a composite polymer structure by combining three different types of monomers into a single bottle brush polymer architecture. The polyoxaalkylene-containing monomers form the backbone, while anionic and nonionic monomers are grafted as side chains. This composite material approach provides synergistic effects that enhance silica scale inhibition effectiveness beyond what single-component inhibitors can achieve

Inventive Principle:

Principle #40Composite materials

2Object-generated harmful factors

If mechanical cleaning or acid washes are used for scale removal, then silica scale is removed, but equipment is damaged and hazardous chemicals are required

Engineering Contradiction:

Improvescale depositVSAvoidequipment damage and hazardous chemical exposure

Core Design Contradiction:

Object-generated harmful factorsVSObject-affected harmful factors

Solution Approach 1:

The bottle brush polymer inhibitors are applied in advance to prevent silica scale formation before it occurs. By maintaining silica in a dispersed state through the polymer's steric and electrostatic repulsion mechanisms, the need for subsequent mechanical cleaning or hazardous acid washes is eliminated, preventing both equipment damage and chemical exposure hazards

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent converts the potentially harmful interaction between silica and equipment surfaces into a beneficial effect by using the bottle brush polymer's side chains to interact with silica particles. The polyoxaalkylene side chains provide steric hindrance while anionic side chains provide electrostatic repulsion, transforming what would be a harmful deposition process into a controlled dispersion mechanism that protects equipment

Inventive Principle:

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

3Reliability

If linear polymers are used as scale inhibitors, then some inhibition is achieved, but performance is insufficient compared to bottle brush polymers

Engineering Contradiction:

Improvescale inhibition performanceVSAvoidpolymer structure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The bottle brush polymer structure is segmented into distinct functional regions: the polyoxaalkylene-containing monomer backbone provides the main structural framework, while anionic monomers (such as acrylic acid or sulfonic acid groups) and nonionic monomers are segmented as graft side chains. This segmentation allows each component to perform its specific function - the backbone provides steric bulk, anionic groups provide electrostatic repulsion, and nonionic groups provide additional steric hindrance - achieving superior silica scale inhibition compared to simple linear polymers

Inventive Principle:

Principle #1Segmentation

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 bottle brush polymers effectively inhibit silica scale formation, maintaining higher levels of free silica in solution and preventing insoluble precipitates, thereby prolonging equipment efficiency and reducing downtime in applications like reverse osmosis, cooling towers, and geothermal systems.

Implementation Method 1

maintaining silica in a dispersed state

Methodology Applied

Scientific EffectSteric repulsion:

Implementation Method 2

The scales can deposit on the water treatment or production equipment

Methodology Applied

Scientific EffectElectrostatic repulsion: Ion Repulsion/Attraction

Data Source

PatentUS11873243B2Inhibition of silica scale using bottle brush polymers

Publication Date: 2024.01.16 DOW GLOBAL TECHNOLOGIES LLC

AI summary

A method for inhibiting silica scale formation which treats aqueous systems containing silica with a bottle brush polymer. The bottle brush polymer includes a repeat unit obtained after polymerization of one or more anionic monomers, and a repeat unit obtained after polymerization of one or more polyoxoalkylene-containing monomers. The bottle brush polymer may further include a repeat unit obtained after polymerization of one or more nonionic monomers. The addition of the bottle brush polymer to the aqueous system results in the inhibition of silica scale.