Implementing AI to improve foam control in pulp mill washers

In this case study, we present and discuss HABER’s approach and AI’s role in addressing a leading integrated paper mill’s longstanding issue of loss in productivity due to the presence of excess foam in washers.

Introduction: 

During the process of pulp production, black liquor is obtained. Black liquor has a high propensity to foam as it consists of sodium hydroxide, sodium sulphide, hemicellulose, amongst other organic compounds.

Foam is detrimental to the environment and can increase COD, BOD, and colour levels in the effluent. Excess foam in washers results in high soda loss and a low production rate. It also creates workplace safety hazards and raises production costs. Excess amount of foam results in a negative impact to the process, affecting the quality standard of the product and equipment efficiency.

Defoamers are integral to pulp washing, screening, and bleaching. They can function in extremely acidic or alkaline environments, and at high ranges of temperature, as required in the pulp mill. Their main purpose is to improve washing efficiency to maximize the production rate. Improving drainage significantly increases the washing efficiency of the defoamers.

Significant soda loss, a detrimental effect on production efficiency and foam overflow in washers and seal tanks were some of the issues that needed to be addressed and resolved.

Our Approach:

HABER’s eLIXA® platform provides real-time artificial intelligence and machine learning-based closed-loop for defoamer programs.

A specialized defoamer formulation for wash aid application was introduced. Key process variables like pH, temperature, conductivity and others were measured and uploaded to the cloud in real-time, on which big data analysis was carried out. Based on the analysis, the fully automated eLIXA® controlled chemical feed system, maintained the system parameters within the target range at all times to ensure the peak performance of the washers, by eliminating foam and reducing soda loss.

Results: 

HABER’s solution resulted in the better running of the system with an increased production rate, with:

-       A 10% increase in production rate

-       An 11% reduction in soda loss

-       Significant improvement in drainage

 The implementation of AI/ML optimised the foam control process as it helped in avoiding delays in the solution execution due to human intervention. Due to the optimization of the defoaming process, the product quality improved. Thus eLIXA® helped the mill achieve quality control over their products on a consistent level, with minimum investment involved.

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