Demand Mode Safety Function
Demand mode safety function is where a specified action is taken in response to process conditions or other demands. In the event of a dangerous failure of the SIF, a potential hazard only occurs in … Read more
Tag: Process engineering
How HAZOP Technique is used to identify Hazards in a Process
In functional safety, hazards are events which have the potential to cause harm such as personal injury, damage to the environment or the business. Hazards in the process industry might include: the pressure of liquid in a vessel (high pressure … Read more
Combustion & Temperature Control for a Direct-Fired Process Heater
The figure below shows the control schemes applied to a direct-fired process heater.
From the diagram above, the heat from the burning fuel is applied directly to the tubes carrying the … Read more
Steam-heated Reboiler Control System
When steam-heated reboilers are used in distillation columns and the heating medium is steam, a flow control loop for the steam will typically be incorporated. The control valve can then be placed either in the steam or condensate line. Steam … Read more
Furnace Control System for a Rapidly Changing Demand
Let’s consider the figure below:
In the system above, the output of temperature controller TC represents the process demand, and this signal is applied as one of the inputs, each to a … Read more
Instrumentation and Controls for a Steam Desuperheater
A steam generator is an item of plant equipment that is found in almost every manufacturing site, and its output of steam has many critical uses in a variety of production processes.
Steam has been assigned a measurement quality and … Read more
The Instrumentation for Furnace Control
The figure below shows a typical basic furnace used to raise the temperature of a heat-transfer medium that is used on other equipment in a plant process.
From the figure above, the temperature of the … Read more