Closed-Loop Acid Regeneration System Commissioned for Steel Pickling

ANDRITZ and JSW Steel Coated Products Limited have collaborated to implement a second hydrochloric acid regeneration plant at the Vasind Works facility in Maharashtra, India. The project integrates closed-loop processing technology to recover spent pickling acid for cold-rolled and galvanized steel production operations.

Cooperation and Operational Context
The deployment addresses the technical challenge of managing chemical waste generated during large-scale metal surface treatment. JSW Steel Coated Products Limited required a scalable recovery system to support a new pickling line with an annual processing capacity of 1.3 million tons. ANDRITZ provided the engineering and technology to meet these expanded processing requirements, allowing the manufacturer to align output volume with internal chemical recycling capabilities.

Technical Solution and Process Mechanisms
The technical solution utilizes a continuous regeneration process to convert spent hydrochloric acid back into reusable acid. ANDRITZ supplied and commissioned the technology, which operates with a processing capacity of 6,400 liters of spent pickling fluid per hour. Within the closed-loop system, the chemical reaction separates the acid from dissolved metals. This process also yields iron oxide as a physical by-product, which is extracted from the system and routed for secondary industrial applications.

Deployment and System Integration
The regeneration plant is deployed at the Vasind Works site, operating in tandem with a previously installed ANDRITZ unit to serve the entire site's pickling operations. Following mechanical installation, the system underwent start-up procedures and performance validation to verify compliance with designated environmental and process parameters. The integrated infrastructure now continuously receives spent fluid from the primary pickling lines and cycles the regenerated hydrochloric acid directly back into the surface treatment process.

Industrial Applications and Quantifiable Impact
In the coated steel manufacturing sector, stable acid management is required for continuous material processing and environmental compliance. By deploying this closed-loop processing architecture, the facility minimizes hazardous waste generation and decreases its reliance on fresh chemical inputs. Performance validation confirms that the regenerated hydrochloric acid now covers approximately 99 percent of the pickling operations' total acid requirements, establishing a highly efficient chemical recovery loop for the plant.

Edited by Aishwarya Mambet, Induportals Editor, with AI assistance.

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