Recovering a KZN Dairy's Wastewater for Reuse in Production Processes
A dairy production facility in KwaZulu-Natal was looking to reduce their wastage by recovering their liquid waste for reuse in their production processes.
The process of making cheese from milk consists of three steps: Coagulation, dewatering, and refining. During the first step, coagulation, the liquid milk is transformed into a semisolid. As the milk solidifies, it forms curds and whey. The curds are the solid parts and the whey is the liquid.
Using a whey concentrator, many dairies recover the whey protein. The whey's liquid byproduct that's left over after this process can either be reused or disposed.
This particular dairy in KwaZulu-Natal had no choice but to discard the whey's liquid byproduct or waste, because it contained high levels of total dissolved solids (TDS), total organic carbon (TOC), and biological content.
Addressing this wastage, our team designed a solution that included a reverse osmosis system to treat the liquid waste at a recovery of 80%. The solution also incorporates pre-treatment, filtration and disinfection.
The pre-treatment stage consisted of introducing sodium hypochlorite volumetrically introduced in order to aid in the oxidation of organics and microbial content before moving on to the next stage of treatment.
Reverse osmosis technology is used for the removal of dissolved ionic species in order to achieve the
required final product water quality.
Finally, the RO permeate water is further treated by introducing sodium hypochlorite in the post-treatment stage. Acting as a disinfectant, the sodium hypochlorite keeps biological growth at bay.
Once the solution was implemented, it enabled the dairy to recover 80% of the wastewater. This amounts to a total of 5 200L/hour of usable, clean water. This water has significantly lower levels of TOC, TDS and biological content compared to the untreated water. It is now successfully being reused by the dairy as process water.
To learn how WPS can help solve your water challenges, contact us.