AIChE / Delta Process Academy Seminar 2016 - Safe start-up of Chemical Plants - Consequences for design, engineering, commissioning and operation

Excellence in safety is the key to address the increasing complexity of industrial production processes and the increase of rules and regulations both in Europe and internationally. One of the priorities is reduction of the number of incidents during start-up and non-routine operation of chemical plants.

25 years lessons learned start-up and non-routine operation of a cracker plant, Geert Vercruysse, BASF

The process safety concept of a plant is determined during the engineering phase of a project. Once the process is started this safety concept will be validated during the life cycle of the plant, based on operational experience and lessons learned from incidents. In the presentation three incidents, related to start up and shutdown, will be elaborated in detail and its impact given on the process safety concept. Further it will be illustrated that similar scenarios can/could occur in different process unit set ups.peration of a cracker plant. Presentation file here

Safe Start-up culture, Marcel Beekman, Fluor

Safe Startup development should be done early in design phase. Considerations for Design, Engineering and Construction phases are discussed:

  •  Company Culture
  •  Design and good operability practices
  •  Safety in Construction
  •  Turn Over Development and Safe Hand Over
  •  Training and familiarization of Operations
  •  Pre-commissioning
  •  PSSR/Operational Readiness
  •  Commissioning and Start-up 

Presentation file here

Pressure Relief Systems - Thinking Ahead for a Safe Start-up, Bob Siml, Siemens 

It is essential to have a thorough Management Of Change (MOC) process in place to identify pressure relief systems that may need to be adjusted.

Analysis tools can improve the detailed analysis of complex pressure relief systems such as dynamic simulation, QRA and Safety Instrumented Systems. Non-normal operations during start-up should also be considered to ensure proper safeguards are in-place. Further, training, operational procedures and the limitations of relief systems must be considered.

One of the challenges is to consolidate all documentation in a digital platform to facilitate PHA’s and prestart-up reviews. Also addressed are lessons learned in the design, procurement, and commissioning process. Presentation file here

Design considerations for switching a cracking furnace between normal operation and decoke mode, Menno van der Bij, Technip

Design considerations for switching a cracking furnace between normal operations and decoke mode This paper presents the design considerations for the change-over system for the motor operated cracked gas valve (CGV) and decoke effluent valve (DEV) of ethylene cracking furnaces.

A steam cracking furnace regularly requires decoking due to coke formation inside the radiant coil. The furnace is at end of run (EOR) condition when the furnace reaches one of the EOR criteria. Then the furnace has to be switched from cracking mode to decoking mode. During decoking mode, air is introduced into the furnace in order to gently burn off the coke layer.

Switching a furnace from cracking mode (steam-hydrocarbon service) to decoking mode (steam-air service) requires an adequate handling of the involved risks in order to guarantee safety for people and environment.

This paper will explain the functionality and the safety principles of the system resulting from the performed hazard and operability (HAZOP) study and safety integrity level (SIL) review meetings. It addresses how the cracking and decoking mode switch-over can be designed to comply with today’s standards. Presentation file here