Industry data show that both major and minor leaks are often associated with relief valves, typically in terms of the passage of gases through seat. One of the most common causes of this leak is improper closure of these valves after a release/discharge. Although such scenarios are rare, when they happen, they contribute to sustained, undetected leakages for extended durations. The IIOT-based devices discussed below give digital insights into these valves. The solution described in this approach comprises the following major components: ○ Wireless Edge devices (powered by batteries) are clamped onto the outlet lines of relief valves, connecting these valves to the plant flare system, and are capable of detecting major and minor leaks. These devices generate acoustic signals and transmit acoustic data (typically 0 to 255 counts based on acoustic intensity) and temperature readings to the host system, which is typically the plant’s distributed control system (DCS). ○ The technology utilises a wireless infrastructure to communicate the information generated. ○ The host system gathers and time stamps the data. The algorithm of the host system analyses the data and identifies the nature of valve release, major and minor leaks. This information is presented clearly to the end user, along with event timestamps, through the dashboard mobile apps, enabling proactive maintenance and thereby improving asset management. A typical schematic representation of the solution is given in Figure 3 .
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associated with implementing this technology in a typical refinery complex. Technological framework Relief valves are critical safety components in flare systems, designed to automatically discharge excess pressure from process equipment, thereby preventing catastrophic failures such as explosions or fires. By directing gases and liquids into flare headers, relief valves ensure that these hydrocarbons are safely combusted in flare stacks, thereby protecting both personnel and infrastructure from potential hazards. However, as mechanical devices, they offer no real insight into or diagnostics of their health. Figure 2 Year-wise flaring volume for India. Source: World Bank’s Global Flaring and Methane Reduction (GFMR) Partnership
FOUNDATION Fieldbus
Hydrocarbon leakage through relief valve detection and estimation Typically, in the hydrocarbon industry, flares are equipped
WPN
with flowmeters for flare leakage estimation. These flowmeters are capable of
estimating flare flow rates and molecular mass, which gives operators some idea of the flare composition. Although capable of measuring flaring volume in case of high flaring during plant
Figure 3 Typical schematic of solution
Refining India
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