Maintenance of continuous emissions mercury monitoring systems (HgCEMS) under the U.S. EPA Portland Cement (PC) MACT rules

With the issuance of EPA´s Portland Cement (PC) Maximum Achievable Control Technology (MACT) rule, the industry is faced with a number of new challenges relative to both hazardous air pollutants (HAPs) control and monitoring. This paper focuses on the monitoring of mercury (Hg), with particular emphasis on electronic (AKA “real-time”) Continuous Emissions Monitoring Systems (CEMS). A description of the monitoring technology and the experiences and requirements for its service and maintenance is also included. Finally, the case is made for the prospect of using a real-time HgCEMS for air pollution control equipment performance monitoring and control, as well as regulatory compliance.