USE OF ADVANCED “DOSE TO DEMAND” TECHNOLOGY FOR ENHANCED LIQUID PHASE ODOR AND CORROSION CONTROL

This paper presents various means of utilizing information technology to achieve more cost effective liquid phase odor control (LPOC). Control of odor and corrosion due to hydrogen sulfide (H2S) in sewage collection systems is not a new requirement, but new technology is continually being developed that allows more effective and economical control. The typical sewage flow patterns present in municipal collection systems are not conducive to the traditional methods of dosing LPOC products, namely feeding at a fixed rate and simple flow pacing.Advanced process control systems have been developed to specifically account for the dynamic nature of H2S generation in sewage force mains and gravity interceptors. As a result, this “dose to demand” technology generates a unique LPOC product dose profile that tracks the daily, weekly and monthly fluctuations in key sewage parameters that dictate degree of septicity in the portion of the sewer requiring odor control. An effective dose to demand system is tailored to the specific project requirements and is composed of various information technology components such as advanced dosing controllers, liquid and vapor phase data collectors, storage tank monitors, data transmitters, databases and websites. This paper will summarize proven and emerging examples/capabilities of these various process control components and their integration to create real time dose to demand systems.Operational data from a cross section of installations throughout the United States will be presented in the form of three case studies. The case studies will highlight the improved performance and/or the reduction in LPOC product usage (typically in excess of 20%) obtained from utilizing advanced dose to demand process control systems. Additional benefits such as improved shipping logistics, inventory management, customer access to data and remote process control will also be covered.