Dairy processing plants may be losing millions of dollars each year through product losses entering wastewater systems, with online Total Organic Carbon (TOC) monitoring offering a way to improve process control and reduce waste.
Continuous TOC monitoring can help dairy manufacturers identify when milk products are entering wastewater streams, allowing operators to respond more quickly and reduce losses.
Historically, efforts to reduce wastewater loadings were driven by rising treatment and surcharge costs. However, the value of the product being lost through wastewater has become an increasing concern for processors.
More than 90 per cent of a dairy plant’s organic waste load can come from milk components including lactose, proteins and butterfat lost during processing.
Industry estimates place annual product losses at around 2 to 3 per cent for a typical dairy facility. According to the article, a plant operating at a 2.5 per cent loss rate could lose more than $5 million annually in product value, along with almost $900,000 in additional wastewater treatment costs.
Even modest reductions in product loss can generate savings. A 15 per cent reduction in losses could save a typical dairy plant more than $750,000 annually in product value, while also reducing wastewater treatment expenses and potential surcharge costs.
Limits of conventional testing
Dairy plants have traditionally relied on Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) testing to measure wastewater strength and identify product loss.
BOD measures the amount of oxygen required to break down organic material in water, while COD provides a related measurement.
However, laboratory testing delays can limit the usefulness of these methods for real time process control. BOD analysis can take up to five days, while COD results may take several hours.
As a result, periodic testing may only provide limited visibility into short term product loss events, making it difficult for plants to identify the source of excessive wastewater loads.
Real time monitoring with TOC analysis
TOC measures the carbon content of dissolved and suspended organic matter in water and is widely used to estimate the quantity of milk products entering wastewater streams.
According to the article, there is a direct relationship between TOC levels in wastewater and the amount of milk lost during production.
The Hach BioTector B7000 Dairy TOC analyser was developed for dairy processing applications and provides continuous monitoring of milk in wastewater.
The system includes a Lost Product Index (LPI) module, which links TOC levels in wastewater to estimated milk losses at a given point in time. Operators can combine this data with wastewater flow rates to calculate losses by hour, shift or day.
The information can also help identify how equipment performance, operational practices or production incidents affect product loss levels.
Industry studies cited in the article indicate that continuous TOC monitoring can help dairy processing plants reduce product losses by more than 15 per cent.
The article also states that continuous monitoring may support lower wastewater treatment costs, reduced water and energy consumption, fewer discharge issues and improved recovery of saleable product.
For more information visit https://au.hach.com/industries/food
