Detection of Antifreeze (Brine) Leakage into Wastewater

User Benefits

- Antifreeze that has leaked into wastewater can be detected with a TOC analyzer with high sensitivity from low concentrations to high concentrations. - The on-line TOC analyzer (TOC-4200) can continuously measure samples with a cycle of 10 minutes or less, enabling continuous monitoring of wastewater. - The laboratory TOC analyzer (TOC-L) makes it possible to respond to a wide range of applications with a single instrument, including not only wastewater management, but also quality control and investigation and research.

Introduction

Ethylene glycol and propylene glycol are used as heat transfer media in air conditioners, refrigerator freezers, and similar equipment. They are also widely used in antifreeze (brine) owing to their low freezing point and low cost. However, ethylene glycol is especially toxic if it is ingested and metabolized in the human body, and causes kidney damage and other health problems. For this reason, it is important to monitor wastewater to enable detection of leakage of antifreeze, and especially contamination of rainwater lines that are not subject to wastewater treatment. UV analyzers are widely used to monitor organic substances in wastewater, as they are inexpensive and the burden of maintenance is small. However, UV analyzers are not suitable for applications that involve detection of antifreeze leaks because they cannot detect antifreeze agents. On the other hand, because total organic carbon (TOC) analyzers can detect organic compounds regardless of the type, they can reliably detect leaked antifreeze. Many public regulations on the concentrations of organic compounds in wastewater discharged after water treatment are specified by COD (chemical oxygen demand), and there are also cases where COD analyzers are used in antifreeze leakage detection applications. However, in recent years there has been on ongoing changeover to TOC analyzers in view of the disadvantages of COD measurement, such as the long measurement time and the influence of inorganic salts in samples on measured values. This article introduces an example of detection of leaked ethylene glycol in wastewater utilizing a Shimadzu TOC-L total organic carbon analyzer, which uses the combustion catalytic oxidation method. In addition, confirmation of the correlation of TOC and COD was conducted.

19 de noviembre de 2024 GMT