background

Litehouse company mainly produces salad dressings, sauces, vegetable dipping sauces, seasonings, cheese and other products. The Litehouse food processing plant located in Lowell, Michigan generates an average of 75000 gallons of wastewater per day. The wastewater treatment workshop of the food processing plant uses two Dissolved Air Flotation (DAF) systems, and the treated wastewater flows into the city's wastewater treatment plant. The city has strict wastewater discharge standards, and if food processing plants fail to meet the discharge standards, they must pay high fines.

In the wastewater generated by food processing plants, the organic content and flow rate vary greatly. Previously, the wastewater treatment workshop mainly controlled the process and set emission limits based on BOD and COD detection results.

The daily discharge limit for the wastewater treatment workshop is 800 pounds of BOD. The operator conducts COD analysis at the beginning of the daily work shift. The workshop operates daily based on the ratio of COD and BOD to ensure that the daily BOD emission limit is not exceeded. It takes about 5 days to obtain the BOD analysis results in a local third-party laboratory, which increases the company's operating costs. Although COD analysis is fast (about 2 hours), it requires the use of hazardous chemical reagents.

In addition, the accuracy of BOD and COD analysis is affected by chemicals other than organic matter in the sample, so the company must fully consider this important influencing factor when carrying out emission compliance work. Due to the inability to collect real-time water quality data, the wastewater treatment workshop is unable to process a large amount of wastewater and has to hire other wastewater treatment plants to transport the untreated wastewater, which costs over 1.2 million US dollars annually.

　　Solution

Food factories urgently need a robust organic matter detection method to monitor high salt and fat, oil, and grease in samples. They chose the Sievers InnovOx TOC analyzer to complete this task. In the process of monitoring emission limits, the shorter the analysis time, the more wastewater the food factory can treat, and the faster the operators can adjust the process based on the monitoring results. The food factory used organic matter monitoring data as the main parameter for optimizing the process and conducted a 3-month experiment using the Sievers InnovOx TOC analyzer. TOC analysis is an accurate, precise, and fast organic matter monitoring technique that enables users to have reliable evidence when making process decisions. The real-time data changes of upstream processes enable food factories to immediately adjust their processes, greatly reducing the transportation costs of untreated wastewater. Figure 2 compares the average monthly wastewater treatment volume before and after using the Sievers InnovOx TOC analyzer.

　　result

The monthly wastewater treatment capacity has increased by 29%.

Significantly reduce the transportation cost of untreated wastewater, saving over $700000 annually.

Compared to the 2-hour COD analysis and 5-day BOD analysis, TOC analysis takes an extremely fast time of only 6 minutes.

Due to the success of the Sievers InnovOx experiment, the food factory has decided to use TOC analysis to monitor the organic matter generated by upstream processes. The conversion of BOD: COD analysis to TOC analysis in food factories greatly saves time and cost in process adjustments.

　　Conclusion

After evaluation, Litehouse has decided to install the Sievers InnovOx ES laboratory type TOC analyzer in its food processing plant. Laboratory type analyzers can take samples from different locations, so food factories do not need to install multiple online analyzers in the production line. The laboratory analyzer is flexible in operation and is the best choice for food factories. Litehouse company uses Sievers InnovOx TOC analyzer for TOC monitoring, which improves the wastewater treatment capacity and eliminates accidents of excessive discharge. The wastewater treatment workshop has increased the on-site treatment capacity of wastewater, greatly reducing the transportation cost of untreated wastewater.