Technoeconomic assessment of metal recovery from chloric-based spent pickling liquor in Indonesia: A case study on Java Island

¹ Department of Mechanical Engineering, Universitas Negeri Surabaya, 60213 Surabaya, East Java, Indonesia
² Department of Natural Science, Technological University Panglong, Shan State, Myanmar
³ Institute of Raw Material Preparation and Environmental Technology, University of Miskolc, 3515 Miskolc, Hungary
⁴ Department of Mechanical Engineering Education, Universitas Negeri Surabaya, 60213 Surabaya, East Java, Indonesia
⁵ Department of English Language Education, Faculty of Letter, Universitas Negeri Malang, 65145 Malang, East Java, Indonesia

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract

The conventional treatment of spent pickling liquor (SPL) generated by the steel industry poses significant environmental risks while overlooking valuable resource recovery opportunities. This study assesses the technoeconomic feasibility of metal recovery from SPL in Java Island, Indonesia. Findings indicate that conventional practices—neutralization and landfill disposal—remain widespread, despite their substantial environmental impact and lack of economic benefit. In contrast, this study identifies an integrated hybrid recovery approach, Scenario C, which combines selective precipitation with electrowinning, as the most effective option. A comprehensive process flow was developed and evaluated against conventional disposal in terms of recovery efficiency, operational costs, and contextual suitability. Treating 1,000 cubic meters of SPL annually can yield approximately 340,000 kg of iron, 24,000 kg of zinc, 4,500 kg of copper, and 1,500 kg of nickel, generating an estimated annual revenue of USD 171,300 and a net profit of USD 118,800 after accounting for annual energy and fuel costs of USD 52,500. Levelized cost analysis and sensitivity assessments further confirm the financial viability and resilience of Scenario C under varying market and operating conditions. The results demonstrate that implementing Scenario C for SPL management aligns with circular economy principles and delivers substantial financial and environmental benefits. This approach represents a sustainable and economically advantageous alternative to conventional SPL disposal methods in Indonesia, particularly for high-output regions such as Java Island.