Zero Liquid Discharge
Most industrial processes rely on fresh water, which often results in a wastewater stream. This polluted and contaminated water represents a cost for treatment, discharge or offsite disposal, and environmental concerns. Zero Liquid Discharge (ZLD) systems are designed to treat this wastewater, letting you recover and reuse both water and valuable chemicals directly at the production site. This is crucial for achieving profitable circular solutions.
Reuse water, recover value
- Increases water usage efficiency by removing liquid waste and treating water for reuse
- Some processes may recover valuable resources such as metals and minerals
- Easily adjustable systems are future-proof to your growing needs and changing regulations
- Less waste means lower disposal costs and reduced need for new resources
- Lower investment, installation and operational costs compared to traditional evaporation technologies
Every industrial effluent stream is different – each with its own challenges. That’s why Alfa Laval’s Zero Liquid Discharge (ZLD) solutions are engineered with precision, combining advanced technology and deep process expertise to minimize waste and, when needed, eliminate wastewater discharge. From modular, pre‑assembled systems for fast integration to fully customized designs for unique processes, we work closely with you to ensure optimal performance, regulatory compliance, and a positive impact on both your business and the planet.
Want to learn more?
Every industrial effluent stream is different – each with its own challenges. That’s why Alfa Laval’s Zero Liquid Discharge (ZLD) solutions are engineered with precision, combining advanced technology and deep process expertise to minimise waste and, when needed, completely eliminate wastewater discharge. From modular, pre‑assembled systems for fast integration to fully customised designs for unique processes, we work closely with you to ensure optimal performance, regulatory compliance, and a positive impact on both your business and the planet. We also bring proven experience across a wide range of processes and industries, among others:
- RO-reject treatment
- Spent caustic recovery
- Scrubber brine
- Chemical processing
- Mining and metals
- HVO
- Power
- Battery production and recycling
What is Zero Liquid Discharge (ZLD) and why is it important?
ZLD technology addresses the growing water challenges that industries are facing, including waste and pollution minimization, water scarcity, compliance with legislation and circularity. The ZLD market is significant and expanding, driven by those megatrends. Most industrial processes rely on fresh water, which often results in a wastewater stream. This polluted and contaminated water represents a cost for treatment, discharge or offsite disposal, and environmental concerns. ZLD systems are designed to treat this wastewater, letting you recover and reuse both water and valuable chemicals directly at the production site. This is crucial for achieving profitable circular solutions. By reusing water and recovering value with ZLD technology, industries make their operations more sustainable and efficient. A ZLD system enhances resiliency, aligns profit and sustainability goals, leading to a more robust business, less vulnerable to external changes.
ZLD is a combination of technologies
The goal of a ZLD system is to minimize liquid waste and convert it into reusable clean water and solids that can be used, sold, or safely disposed of. A ZLD system combines technologies to reduce wastewater as much as possible, while producing concentrated solids and high-quality water at the end. The most common process steps follow this sequence:
- Chemical and/or physical pre-treatment of the raw wastewater. The aim is to prepare the stream for the requirements of the downstream steps. Typical examples of pre-treatment can be chemical reaction, precipitation, flotation or filtration.
- Membrane treatment and pre-concentration. Reverse osmosis is a common option to decrease the wastewater volume as much as possible at minimal cost.
- Thermal evaporation of the brine (reject) from the membrane step. Thermal evaporation further reduces the brine volume.
- Crystallization of the concentrated brine. It is during this step that the solids (crystals) are produced for disposal or reuse, achieving Zero Liquid Discharge.
With a Zero Liquid Discharge system in your process, you can achieve:
Water recovery
With an ZLD system in your process you can recover the solvent (water) for reuse in the process, up to 98%. By cleaning and reusing water, you can limit the amount of fresh water that enters your plant and reduce or even eliminate wastewater.
Waste minimization
Reduce or remove liquid effluent due to constraints in downstream water treatment. This reduce the need for waste storage disposal and reduces transportation costs.
Resource recovery
The solids produced vary and include salts or chemicals that can be resold or reused in the initial process. This turns what was previously waste into a product, improving the profitability of your business
Industries and applications
AlfaFlash ZLD systems are designed to meet the needs of a broad range of applications:
Discover what ZLD can do for your business!
Get an overview of the Zero Liquid Discharge System
Learn more how Alfa Laval solutions can turn waste into value-add product by exploring the Zero Liquid Discharge system.
A choice of configurations
Mechanical vapor recompression (MVR)
Alfa Laval ZLD systems can be designed with MVR using electrical power to drive the evaporation process. An electrically driven fan increases the condensation temperature of the vapor in the evaporator before it is routed back to the heat exchanger where the latent heat is recovered. This configuration is ideal when there is no thermal heat source and when boiling point elevations are moderate.
Multi-effect systems
Alfa Laval ZLD systems can be designed using a thermal heat source such as steam or hot water, with one or several effects depending on the capacity requirements and your energy efficiency targets. The configuration is ideal when thermal heat sources are available and is generally more attractive in terms of capital expenditure.
AlfaFlash working principle
Dig deeper into the functions of the Alfa Laval Zero Liquid Discharge system. Watch the AlfaFlash animation and experience our forced circulation evaporation technology first hand.
Alfa Laval opens state-of-the-art service centre that recycles almost 100 percent of its water
Alfa Laval's new service centre in Frechen, Germany, will be one of the largest for plate heat exchangers in the world. In addition, it is also a technically advanced and sustainable facility, capable of recycling almost 100 percent of its water using Alfa Laval Zero Liquid Discharge technology.