Cracking & Chemical Treatments of Purification

PCH/RCIVAPO-E

Who should attend?

  • This course brings technical information on the steamcracker sections focused on chemical transformations: cracking, gas purification, hydrogenations or purification stages on a solid (drying).
Audience :
  • Operating personnel in steamcracking plants: experienced outside operators, panel operators, foremen and all technicians involved in the working of these sections.

Level : Proficiency

Course Content

  • BLOCK DIAGRAM OF THE STEAMCRACKER UNIT

      • Roles of the various sections.
      • Feedstock origins, products types, yields.
  • MAIN PETROCHEMICAL INTERMEDIATES

      • Definition of hydrocarbon families. Feedstock composition.
      • Potential outlets and main industrial uses of olefinic, diolefinic and aromatics hydrocarbons.
  • CHEMICAL REACTIONS & CATALYSIS

      • Chemical reactions, chemical reaction uses for the mass balance production.
      • Studies of the thermodynamic conditions to make the chemical reaction feasible.
      • Chemical reactions limited by the chemical balance, rules to outline the shift in the chemical balance.
      • Speed of chemical reactions. Effect of a catalyst, catalyst behavior. Poisons and inhibitors.
      • Nota: these basic elements have been provided throughout the course as they enhance the understanding of the different topics.
  • STEAMCRACKING

      • Onsite unit description; operating conditions of the different sections, product yields.
      • Analysis of technical characteristics of desired transformations.
      • Elements of pyrolysis monitoring: definitions of the severity and the selectivity.
      • Influence of the operating parameters/pressure, temperature, flowrate, steam dilution ratio on the unit performances.
      • Impact of the feedstock origin on product yields.
      • Regulation and advanced process control.
  • CRACKED GASES PURIFICATION

      • Main washing systems for cracked gases: choice of systems implemented.
      • Amine washing system: absorption and regeneration.
      • Caustic soda washing system and treatment of waste caustic sodas.
      • The sequence of washing stages.
      • Influence of the operating parameters on the washing quality.
  • DRYING OF CRACKED GASES

      • Adsorption-desorption balance.
      • Operation of cracked gases dryers during the drying and regeneration steps, drying optimization (temperature/run relationship).
  • TREATMENTS WITH HYDROGEN

      • Role and purpose of the different hydrogenation processes, chemical reaction characteristics, main types of catalysts implemented.
      • Purification of hydrogen by methanation.
      • Studies of selective hydrogenation units for C2, C3 and C4 cuts and hydrotreatment units for pyrolysis gasolines: analysis of the operating conditions of the unit, operating parameters of the plant, case studies for unit adjustment, main incidents.
  • DISTURBANCES - INCIDENTS

      • Incidents on the furnace: loss of feed flowrate, high temperature on one or more paths - Loss of heat - Loss of water hardening…
      • Incidents on gas washing towers: loss of topping up of washing base, abnormal temperature of the base, loss of water washing at outlet of the tower.
      • Incidents on dryers: insufficient regeneration, humid gas at outlet.
      • Incidents on selective hydrogenations: management of feedstock inhibitors, changes of hydrogen quality, loss of activity and/or selectivity.
      • Nota: this part is delivered through case studies and analysis of feedback of on-site incidents.

Learning Objectives

  • Upon completion of the course, participants will be able to:
  • analyze chemical or physico-chemical phenomena involved in the different sections of the steamcracking complex, in order to solve problems in case of incidents,
  • explain the meaning of the main operating parameters of these processes and the influence of operating variables.

Ways & Means

  • Case studies done in groups based on typical running situations presented in the course.
  • Possible intervention of operators experienced in the daily operation of the plant.