Emergency Shutdown System (ESD System)

Emergency shutdown system or ESD is a system that is used in hazardous areas to prevent situations that could have catastrophic effects economically, environmentally, or operationally. They are designed to minimize the consequences of emergency situations, such as injury to personnel or damage to equipment, by protecting against things like leaks, escape of hydrocarbons, fire outbreaks, and explosions. Emergency shutdown systems can be found on oilfields (oil well heads), oil and gas processing plants, gas and steam turbine power plants, and boilers.

Emergency shutdown systems work

Emergency shutdown systems work by determining when there is a critical condition within a system and then activating to quell possible leaks, explosions, or other types of major malfunctions.

The activation of an ESD may include

Shut down of part systems and equipment
Isolation of hydrocarbon inventories
Isolation of electrical equipment
Depressurization or blowdown
Emergency ventilation control
Closure of watertight doors and fire doors

For example, when used in an oil well, the emergency shutdown system is in place to prevent the pressure from bursting through the wellhead if the pressure within the system exceeds a preset limit and becomes over pressured.

Similarly, the pressure inside a boiler can increase above safe levels and cause the boiler to explode. In this system, both the pressure and temperature of the steam can trigger an ESD activation when they exceed a preset value.

When used in power plants, emergency shutdown systems are triggered by a few different things. In one application, once the temperature of gas exhaust reaches an unsafe level, an ESD will shut down the turbine producing the exhaust to lower the overall temperature of the system.

Typical Actions from an Emergency Shutdown System

Shutdown of part systems and equipment
Isolate hydrocarbon inventories
Isolate electrical equipment
Prevent escalation of events
Stop hydrocarbon flow
Depressurize / Blowdown
Emergency ventilation control
Close watertight doors and fire doors
Centralized Project Development for Both Safety and Process Needs

Since ESD System is built on the same control platform as the Process Automation System, you can address your process control and functional safety needs with a common control platform.