Veolia aids in achieving Zero Liquid Discharge

Veolia co-developed a zero-discharge wastewater treatment solution, including conceptualisation, implementation, and comprehensive long-term operations and maintenance.

The customer is one of India’s largest integrated zinc producers. A joint venture between the Government of India and a globally diversified natural resources company, it has extensive mining and smelting operations in the arid lands of northwestern India. As a corporate citizen, the customer is highly socially responsible, ensuring that it gives back to its local communities and stays sustainable despite the constraints of its sector. 

The customer was based in an arid region, so it viewed water conservation as a critical social responsibility. It was also committed to giving back to the communities in which it existed and chose Veolia as its partner in this mission. Veolia served the customer to eliminate groundwater contamination and reduce its dependency on local water resources, ensuring the local communities were better served. The customer achieved predictable, cost-effective operations with continuous monitoring via Veolia’s proprietary digital platforms. Clearly defined KPIs and transparent metrics reporting have given the customer complete confidence in our abilities. 

Water management

Zinc extracting is a water-intensive process in which crushed zinc ore is mixed with water to create a slurry and then treated to remove impurities. The resulting wastewater is tough to treat as it contains hardness, a higher load of dissolved solids, and heavy metals. This wastewater needs to be treated before it is discharged or reused.  

Water management was even more critical given that the customer’s operations are based in an arid area. Rainfall is low, and the population is extremely dependent on groundwater. Stringent government regulations also specified norms for water use, with the potential for heavy penalties in case of non-compliance. These factors required the customer to be highly sensitive in managing its water use. 

Veolia’s solution  

The customer’s decision to partner with Veolia was largely determined by our capability to independently design, build, and operate its wastewater treatment system. Veolia has implemented all the advanced technologies (High-rate clarifiers, ultrafiltration, RO, and power-driven crystalliser) and the infrastructure needed to build the whole wastewater recycling plant. Veolia also took the long-term performance-linked service contract for comprehensive operation and maintenance of the supplied plant. The customer trusted us with the entire process, confident we would deliver a flawless and sustainable water treatment solution.  

Since mining and smelting are continuous processes, the water treatment system must be 100 percent available. Any downtime could result in substantial economic consequences, both in lost business opportunities and the costs and time associated with interruptions in operations. 

Veolia’s integrated proprietary solution helped the customer remove heavy metals, hardness, and dissolved solids from the wastewater. More than 95 percent of the wastewater received is recycled back into the upstream metal production process for reuse. Dependence on fossil fuel has largely been eliminated by departing from the conventional steam-based process used to crystallise the waste salts. Veolia’s power-driven crystallisation system has proven to be more robust, efficient and less failure-prone, providing a reliable solution. The waste salts from the crystalliser are further dried using centrifuges and disposed of in Government-approved landfills. Remarkably, the entire system was implemented during the COVID pandemic without missing a single deadline despite the challenges of a global lockdown. 

Our safety standards are consistently higher than regulatory requirements, and our personnel continuously monitor them on and off-site. We rigorously meet and exceed the stringent KPIs agreed upon with the customer, resulting in their regaining total confidence in our capabilities. 

The solution from Veolia assisted the customer in its mission-zero objective, ensuring no liquid discharge in the treatment process and wastewater is recycled for reuse. Further, the system helped the customer give back to the community by reducing the uptake of freshwater from the arid land’s already limited freshwater resources. With the reduction in OPEX and regulatory compliance, the customer has achieved multiple objectives with Veolia’s partnership.  

The product water from the treatment system exceeds the key performance indicators (KPI) set by the customer and meets all the PCB regulations for reuse; below is a snapshot of some of the key parameters achieved.  

·       Zero liquid discharge process 

·       10 percent reduced uptake of freshwater  

·       >95 percent of the wastewater is recycled back into the upstream metal production process for reuse. 

·       >25 percent OPEX cost savings by adopting a power-based crystallisation process compared to a steam-driven system; Simpler to operate with reduced interdependencies

·       Consistently meeting and exceeding regulatory requirements 

For more information, visit: https://www.veolia.com/en

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