Zero liquid discharge, explained simply
Turning a hide into leather uses a lot of water, and that water leaves the tannery carrying salts, organic matter and processing chemicals. How a tannery handles it is one of the biggest differences between one leather supplier and another.
What zero liquid discharge means
Zero liquid discharge (ZLD) is a way of running a plant so that no liquid effluent leaves the site. Wastewater is treated, and the water is recovered and reused in the process. What remains is separated as solid material, such as salts and sludge, and managed as solid waste.
Why it matters
- Rivers and groundwater near the tannery are protected from process effluent.
- Less fresh water needs to be drawn for each batch of leather.
- Water use and treatment become measurable and easier to audit.
What it takes
ZLD needs effluent treatment plants, recovery systems and steady operating discipline. It is not a certificate you buy. It is a way of operating that has to be maintained every day and that can be checked on site.
In our group
The group’s tanneries operate to ZDHC MRSL requirements with zero liquid discharge. Documents are available to buyers on request.
Questions to ask any leather supplier
- Does the tannery that makes my leather run zero liquid discharge?
- How is it monitored and verified?
- Can I see the latest audit or test results?
Planning an order? Request our catalogue and we will share the range, minimum order quantities, lead times and terms.
Request our catalogueRelated
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