Arsenic Removal Process

Benefit from efficient and reliable arsenic removal

The Metso arsenic removal process manages arsenic in process and effluent streams with straightforward precipitation. The process consists of a ferric arsenate precipitation stage followed by neutralization using lime milk. This cost-effective solution provides the high level of process reliability necessary for the treatment of toxic arsenic.

Our arsenic water treatment solution helps reduce environmental impact and produces a stable residue based on globally available, cost-effective iron and calcium chemicals and oxidants.

Brings high process reliability
Improves environmental quality and stable residues
Increases safety
Generates water that meets environmental regulations
Offers process guarantees and tailoring through on-site water testing

Environmental benefits:

Optimizes chemical consumption and water recycling
Controls arsenic discharge into the environment

After the arsenic removal process, the treated water has a low arsenic concentration, typically around 1-3 mg/L. If an even lower arsenic concentration is required, a polishing step with enhanced arsenic removal can be included.

The process comprises the neutralization of acidic streams and the advanced removal of metal impurities, including Ni, Cd, Cu, Sb, and Zn. The final product of the arsenic removal process is treated water that can be safely discharged into the environment or recycled back for process use. The selection of the arsenic treatment process is governed by residual stability. The residue of the arsenic removal process is a stable solid precipitate, which will pass the EU CEN and US EPA TCLP leaching tests for hazardous, arsenic-containing solid waste.

One-stop-shop concept from testing up to EPC
Reliable process operation for the treatment of toxic arsenic
Safe working conditions and controlled arsenic exposure via efficient dust control
High automation rate, minimizing operation costs
High-quality treated water

Process solution examples:

Control of arsenic in acid plant condensate: a ferric arsenate treatment plant to manage arsenic concentration in an acid plant's effluent waters. Heavy metals are removed in the lime milk neutralization stage along with sulfate, which precipitates as gypsum.
Efficient water recycling: water from the arsenic treatment process can be recycled back into the process for reuse and the fresh water intake can be decreased. Total arsenic discharge and effluent volumes can be optimized by efficient overall plant water management.