Acid Inhibitors / Rinse Additives / Pickling Additives

Introduction

To provide high quality, oxide-free steel for finishing requires the use of an acid inhibitor in the pickling operation. An effective acid inhibitor minimizes acid attack on the base metal once the scale has been removed, protecting the surface and optimizing acid utilization.

Activol® acid inhibitors have been proven superior to other brands in field trials, whether hydrochloric or sulfuric pickling; continuous, push-pull lines or batch.

Total benefits of Activol® acid inhibitors may equal 8 times inhibitor cost!

Activol® 1803 Acid Inhibitor

Use

• Activol® 1803 is the premiere additive for hydrochloric acid pickling baths in steel mills. It fulfills all the requirements of a good pickling inhibitor: descaling, high efficiency, durability, rinsability, reduced acid consumption, fume reduction ad uniformly pickled surfaces.

Performance

• Provides a high degree of restraining action to the attack of hydrochloric acid on base steel. Inhibition values typically increase from 92% as inhibitor concentration is raised from 1/15% to ½%.
• Does not retard the descaling rate of oxides on steel surfaces.
• Wetting properties allow a uniformly pickled surface, free from smut or ingrained scale.
• Creates uniformly pickled metal surfaces with a shiny surface and minimal edge corrosion.
• Reduced hydrogen evolution at the solution/steel interface reduces hydrogen embrittlment.
• Pleasant odor facilities manual addition.
• Stable in pickling solutions for extended time periods at elevated temperatures without losing inhibiting action.

Application

• Activol® is used at 1/8% to ¼% based on the amount of raw acid in the pickling bath.

Impact

A major producer of high quality steel sheet was looking for increased efficiency in its pickling operation. The company was already using an acid inhibitor and believed that better inhibitor technology could decrease acid consumption, lower total costs and improve product quality.

The introduction of Activol® 1803 resulted in savings in Acid consumption 194,000 gallons per year/$70,000 per year.

Other Benefits

Other benefits that come with the introduction of Activol® 1803:

• Uniform, brighter pickled surface, free of smut or ingrained scale
• Easily rinsed
• Prevents hydrogen embrittlement
• Reduces acid fumes

HMC 8906-WT Rinse Aid

Use

HMC 8906-WT prevents carryover products from depositing on the immersed steel surface. It also protects the rinsed surface after it exits the rinse section and before it dries. It ensures good wetting on the metal surface and is low-foaming, minimizing disposal and water treatment issues.

HMC 8906-WT eliminates brown or reddish line stop stains that can form on steel as it exits from a continuous pickling line. It also prevents iron hydroxide slimes from forming in rinse tanks as a result of acid bath carryover.

Performance

Protects steel from flash rust after rinse.

Eliminates rinse tub gels and slimes.

Good wetting for better rinsing of chlorides and sulfates.

Nontoxic.

Low-foaming for easier disposal.

Application

Add HMC 8906-WT directly to the rinse tank water. Pre-mixing is not necessary. A typical initial charge to a tank is ¼ to ½% by volume. Subsequent additions depend on the rate of rinse tank dilution. Meter it into the system at a ½ to ¼% concentration with incoming rinse water.

Process & Equipment Information

Acid may be pre-inhibited by the supplier, added upon delivery, or metered in to the pickle line.

Consult your HMC technical representative to discuss the best method for your operation, or to recommend accurate and reliable product metering equipment for your pickle line.