Monitoring and Recording Harmful Gas Detection in a Chemical Plant

An All-in-One Monitoring Solution from dataTaker

CAS DataLoggers recently provided a unique gas and temperature monitoring solution for an international chemical company, where health and safety was an important consideration. Harmful gas detection was placed high on the list of priorities: hydrochloric acid gas was produced when a standard chemical made by the company leaked to the atmosphere as fumes, while chlorine was used as a raw material at the plant. Therefore it was necessary to monitor and record both hydrochloric acid gas levels (HCL) and chlorine (CH2) levels. Comprehensive temperature monitoring was also needed to protect workers from heat fatigue or worse. To effectively accomplish this, the plant needed to monitor and record temperature levels at 20 different locations. Plant engineers stressed the importance of recording this information to compare safety levels before and after this project, so the ability to present accurate data was essential. Management began searching for a versatile datalogging solution to measure all these conditions via a wide range of sensors and which offered both a large number of inputs and a large data storage capacity.

The plant installed a dataTaker DT85 Intelligent Data Logger in an industrial enclosure placed near the points under monitoring over several logging periods. One of the reasons for choosing the dataTaker DT85 was for its 16-48 analog channels. A dataTaker CEM20 Channel Expansion Module was then connected to the data logger to add 20 more universal channels, enough to accommodate the project’s scope. Incorporating the same dual isolation technology as the datalogger, each channel of the CEM20 could be used for 2 isolated inputs or 3 common reference inputs, providing a cost-effective solution. The datalogger was then connected to a multitude of CH2, HCL, and thermocouple sensors. During stand-alone operation, the dataTaker’s rugged design and construction provided reliable operation even in the plant’s extreme conditions.

The dataTaker system continually recorded the levels of hydrochloric acid gas present as fumes and also captured information on the CH2 levels. Additionally, since the plant required a large sample size, the temperature changes in each location were automatically recorded by the data logger once every minute, taken at 20 different points to give an accurate picture of the plant’s temperature over a period of time. The datalogger’s memory capacity could store up to 10 million data points in user-defined memory. To organize all the data for analysis, information from the DT85 was downloaded to an office PC where it was then processed through Excel spreadsheets and displayed in graph form.

Additionally, dataTaker's dEX graphical interface was included free with the datalogger using a pre-installed Windows Explorer-style interface enabling quick setup and configuration. The user-friendly software was configured and ran directly from a web browser, accessible either locally or remotely over the Internet. Users could access logged data and view measurements either as dashboards or in a list using a web browser. Any of the logger's built-in communications ports could be used to view dEX, including Ethernet, USB and RS-232.

The chemical plant’s monitoring project was completed on schedule using the single dataTaker solution. The DT85 datalogger was chosen due to its large number of analog inputs for gas and temperature sensors, increased using the CEM20 expansion module, and connected to the various sensors to accurately monitor all the threats to worker safety. The data logger’s large data storage capacity was especially useful for recording in the widespread locations of the project. Data accessibility was simplified through download to PC and easily organized using Excel. As a result of analyzing all the gas and temperature data, the company’s gas detection system was ultimately connected to a scrubber designed for the effective removal of these contaminants.