Key Success Factors in Commissioning of Ammonia Plants

Key Success Factors in Commissioning of Ammonia Plants team members were involved in commissioning and operation of more than 15 ammonia plants worldwide. The list of our key projects is available here.

We are sharing our experience in line with other recommendations by industry players to support the nitrogen fertilizer manufacturers and EPC companies involved in design and commissioning of ammonia, urea and nitric acid plants. Following key points and lessons learned underline the importance of advance preparation of commissioning phase from early design stages for a smooth and trouble-free start-up.


Commissioning Scope and Contracts:

  • Understand fully and completely the commissioning scope.
  • Clearly understand and define the commissioning contract and remove ambiguity.
  • Ensure all interested parties understand and sign to the related scope within the commissioning manual.
  • Define responsibility and document accordingly.

Fig 1. Ammonia plant during construction

Assets Systematisation

  • Good process systematisation and prioritisation is the foundation to an effective and efficient start-up.
  • A systemised approach will give the project team a close-out focus.
  • Get the project team to understand and agree with the systemized approach
  • Use backwards approach to prioritisation, power and control, utilities, storage, ammonia process and feed system order.


Involvement of Commissioning team at the Design Phase

  • Ensure the commissioning team is present during all project Hazard Studies, HAZID, HAZOP, LOPA, Risk Assessments, P&IDs and 3-D model reviews.
  • Ensure the Commissioning team is involved in the P&IDs and document reviews.


Commissioning Team

  • Magnitude and complexity of the project will determine the size of the Commissioning Team.
  • Discipline balance of the team is key.
  • Consider integration and roles of the client operational personnel.


Industry experience for selecting the commissioning team:

The client company personnel shall get the necessary training and be engaged in the actual work of commissioning, while the responsibility lies with the EPC contractor. This strategy may also help contractors to limit its commissioning manpower to few key resources supported by equipment vendors and ammonia and urea process licensors. This commissioning strategy requires the contractor and company commissioning personnel to be close and work together as one team.

The plant operators and technicians shall be selected and deployed well before commissioning activities. The objective is to give these company resources the full grasp of the project by having them experience the construction and commissioning phases. This prolonged exposure gives the operating staff insight into the equipment design and valuable training opportunity. As a rule of thumb, QAFCO has been deploying the operation staff to the major projects about 12 months before the start of the commissioning giving the operation staff enough time to complete all the training requirements and participate in important construction activities.

The formation of the commissioning team shall start with the selection of the commissioning manager and other key operation personnel that have relevant experience. Part of the team will be tasked to participate in the detailed engineering activities at the contractor’s headquarters. The rest of the team is tasked to build the new operation structure, and source 50% of the operators and technicians from the existing plants where applicable. Based on some companies’ experience with the commissioning of ammonia and urea projects, decisions were made to transfer 50% of the operators and technicians from existing plants and complement with the other 50% new recruits to get an ideal mix of experience and youth. The entire team of shift supervisors and operators was transferred to the new project about 10 months before the start of the first commissioning activities in the utility plants. After a brief introduction to the project followed by project safety training, the commissioning teams were divided into groups led by a supervisor. Each team was assigned to a number of operation units (called systems), and was given the following 2 sets of responsibilities with the objective to have them ready to take control of Operations:

  • Get On-the-Job Training
  • Assist Construction Activities

Fig 2. Ammonia synthesis converter section during loading preparation activities

Commissioning consumables and chemicals

  • All commissioning assignment and consumable items in the project budget shall be correctly accounted for
  • Determine and procure all commissioning consumables well in advance of their need on the project
  • Review commissioning team requirements for any foreign assignment, site location set-up and day-to-day commissioning team consumables
  • If the initial fill of chemicals is to be procured by the commissioning organization, a complete check of what chemicals are required and the due delivery date must be determined.


Commissioning Documents

  • Allocate systems to the commissioning system engineers and establish a secured electronic file location for the documents created. Print out the system files prior to implementation of the procedures in the field.
  • As implementation activities are conducted, the paper copies of the procedures are edited by hand to reflect the actual actions taken per each procedure.
  • Commissioning procedures must address all potential scenarios within the operation of a total system and key items of equipment contained within.
  • Incorporate equipment vendor information within the procedures produced.
  • The commissioning system file is the home for all commissioning documentation created within the system and provides an orderly management structure for all procedures and check sheets created.


Control, Instrument, Electrical, Commissioning Document Preparation

  • The C/E/I (control / electrical / instrumentation) commissioning engineer shall be engaged into the development of the instrument loop testing scheme, schedule to witness all final loop tests, field instrument to operator workstation.
  • Develop suitable paperwork to document and schedule the witness of all motor checks.
  • Develop, with system commissioning engineer, procedures to test interlocks, emergency shut-down systems and control system software control sequences.
  • The C/E/I commissioning engineer will also set up checks to ensure existing equipment utilised in a newly commissioned facility is fully operational prior to handover to the Project team.
  • Ensure that all labeling of cables, panels and junction boxes is adequate and meets all specification.


Mechanical Commissioning Document Preparation

  • Check that all mechanical isometric drawings comply with the system P&IDs to alleviate punch list issues during construction if installation does not mirror the process drawings.
  • Working closely with the construction and fellow commissioning team members, draft cleanliness check sheets and cleaning procedures for all pipe systems. Compile similar documents to ensure the lubrication of equipment is suitably carried out.
  • Compile detailed vessel and equipment on- and off-site check sheets after a review of all vessel drawings. Ensure suitable checks and hold points are incorporated into the construction program so no equipment is finally closed for operation before a commissioning team member has inspected the vessel internals and authorizes closure.
  • Regularly monitor construction progress and highlight installation issues early to avoid later punch list issues and negative schedule implications.
  • Organize a check off and ensure all statutory paperwork is completed on vessels and piping systems to ensure a smooth transition into the commissioning phases.

Fig 3. Mechanical isometric drawings comply with the system P&IDs to alleviate punch list issues

Develop Training Materials

  • Devise what training is required, where and when it will be delivered and what presentation style is suitable; this can range from a simple presentation to full-blown package production and delivery.
  • During training package production consider and utilize as appropriate supplementary training aids as the 3-D plant model and specific simulation tools.
  • Consider who will need to be trained and what level training should be for each specific group.
  • Ensure all training packages produced have the correct sections written, created with the most up-to-date reference material available and cover all key aspects of the process.
  • Extensive training of manpower and well-structured utilization of ammonia and urea Operator Training Simulator help a long way towards smooth start-up of plant.


The dedicated training team shall be responsible for the creation and delivery of all training for the new plant including classroom-related and on the job modules. team is working to deliver an online training program for Ammonia Plant Commissioning during 2020. Subscribe to our newsletter to stay up-to-date with our latest training modules.


Develop Standard Operating Procedures (SOP)

  • Confirm if the commissioning team are to write the Standard operating procedures.
  • During compilation ensure all required sections of the procedure manual are incorporated; if applicable consult statutory guidance (e.g. HSE, Seveso and OSHA).
  • From a contracting commissioning team perspective, ensure all procedures are produced in the required format.


Develop Commissioning Schedule

  • A concise stage 1 plan gives overall guidance to the commissioning activities to be undertaken.
  • A detailed stage 2 commissioning schedule will provide a very accurate duration for all commissioning activities to be performed.


Hand Over Procedure

  • Devise the list of actual handovers the commissioning team will be involved in.
  • Develop the list of documents to be available at each specific handover.
  • Agree with the phased handover approach.
  • Agree with what safe systems of work will be transferred between parties.


Factory Acceptance Testing

  • Fully review all major vessels and equipment and document the vendor site checks required.
  • Challenge the project if the vendor shop test witnessing is not included in the project scope.
  • Conduct detailed checks of all equipment at the vendor shop as per the vessel and equipment drawings.
  • Produce concise inspection and visit reports if modular construction is considered, complete as much pre-commissioning activities at the vendor shop as possible.
  • Make detailed punch lists of the modules prior to shipment.

Fig 4. Converter top dome and main inlet connection

Check Construction and Quality of Build

  • The commissioning team shall start regular checks of the systems being installed at a suitable point during construction.
  • The agreement must be gained with the construction group for the commissioning team to conduct these build checks; the commissioning team must not hinder the construction activities and progress.
  • Regular site inspection of progress is an excellent learning tool for the commissioning team.


Cleaning Procedures and Drying

  • Conduct extensive cleaning procedures to all pipe systems independent of the size and complexity of the system being cleaned.
  • Always ensure all design parameters are considered in the preparation of cleaning procedures and vacuum procedures utilized in the drying process.
  • Ensure the correct cleaning medium is selected: flushing, blowing, use of a pneumatic pig, chemical cleaning, and/or mechanical mechanisms.
  • It is highly recommended that all delicate instrumentation and in-pipeline items are removed for the cleaning procedures. Never attach instrument air lines to field devices until the lines have been suitably blown and proved clean.
  • Cleaning procedures, especially steam blowing, are noisy and dirty activities that by their nature create the potential for flying debris. Ensure safety, precaution measures being fully considered, and an integral aspect of the cleaning procedures are completely adhered to during the cleaning operations.


Pre-Commissioning Procedures

  • Study all relevant engineering documents and manuals to ascertain the list of all pre-commissioning procedures to be conducted.
  • Prepare pre-commissioning procedures at any suitable stage of the construction and commissioning phases. Construction management approval must be obtained for all procedures prepared during the construction phase.


Vessel Check Sheets

  • Compile vessel check sheets utilizing all vendor drawings and manuals.
  • Complete the check sheets at the appropriate time during the vessel installation.
  • Ensure that the correct teams of individuals are present at the time of vessel closure and the correct personnel have inspected the vessel internally and witnessed the installation of internal components prior to vessel closure.


Instrument Loop, Electrical and Control System Testing

  • Establish the methodology for testing.
  • Monitor to ensure that a high standard is maintained during the testing phase and all documentation is correctly completed.


Commissioning Punch List

  • Complete a preliminary punch list at 80% construction completion within a system having first agreed to this timing and when the punch list to be undertaken with the construction group.
  • The punch list must be a complete check of all aspects of the system per the P&IDs and not just a walk around and sight check.
  • A post punch list check sheet must be considered after the punch list is done to ensure everything possible in the system has been checked.
  • Clearly identify all punch list items on the list and lag the defects in the field.
  • Utilize a suitable priority ranking system for the punch list items and indicate those responsible for rectification. Stipulate a completion date for all items to be made good.


Pre-Commissioning HAZOP Studies or Pre-Start-Up Safety

  • Prior to the introduction of hazardous process chemicals, a robust safety checking system must be used.
  • Utilize the existing site system or one based on the best industry practice.
  • The system to be managed by the commissioning manager.
  • The hazard study must take place prior to the introduction of any hazardous chemical.
  • Several layers of audits performed before bringing in the natural gas to the site prior to feed-in.


Commissioning Leak Test

  • Select the appropriate type of leak test, a service test, safe chemical operational pressure leak test, vacuum test or toxic test, and draft procedures accordingly.
  • Diligently complete the procedure accurately documenting all steps and pressures encountered during the test.
  • Conduct a leak test on a full system basis with all possible flanges and potential leak paths included in the test. Document all flanges that could not be included in the test for close leakage inspection e upon commissioning with hazardous chemicals.
  • All components within a system that can’t be subject to the pressure test must be isolated and potential leak checked during commissioning with process chemicals.
  • Make a very detailed check to ensure all isolations are in place before commencing and leak test procedure.


Commissioning and Initial Start-Up Procedures

  • Include in the procedure all possible and credible tests required to fully check out the operation of the system and its equipment.
  • Fully check the full operation scope including start-up, shut-down, and emergency shut-down.
  • The procedure must also check and validate alarm set points and prove the operability of interlocks, hard-wired emergency shut-down systems, and control system sequences.
  • Sound commissioning procedures will draft the number of steps, the description of each step, the detail of the step, a comments area, and a sign-off box.


Hand-Over to Operations

  • Include to the handover paperwork a detailed list of all outstanding work captured in the handover reservations section.
  • Only hand over essential documents to facilitate ongoing operation; it would be advisable to not include all system documentation at this point of the project when time and effort need to be concentrated on the commissioning of the asset.

Key Success Factors and Lessons learned from Commissioning of Ammonia Plants:

 Deploying Company Commissioning Resources early during the Construction phase offers the best training opportunities and reduces construction mistakes.

  • Shift from construction to commissioning site – the whole Construction site is brought under commissioning responsibility at about 70% overall progress. From that point, the operation staff is engaged and the Commissioning Work Permit Rules apply. This shift has positive safety implications as the incident rate significantly drops.
  • Aligning construction and commissioning priorities. It is important that Construction is flexible enough to respond to the Commissioning requirements through.
  • Contracts include commissioning review sessions during the engineering phase to identify how the facilities will be commissioned and the modifications needed to allow quicker and more systematic commissioning of the facility.
  • Temporary Equipment – proper planning of temporary commissioning equipment like boilers, cooling towers is critical during the early commissioning phase to avoid operating process units outside operating limits.
  • Commissioning Spares – insufficient commissioning spares can lead to delays.
  • Preservations – lack of proper preservation of some equipment results in leaking of many ball valves, control valves, and blockage of caged valves.
  • Lack of drain points in the steam system results in longer heating time for some machinery.
  • Collect Trip and Interlock logics and diagrams in one area/document. – If logic blocks are described in separate vendor documents, they may not be reflected in the main plant shut down logic.
  • OTS – Operator Training Simulator – OTS is not delivered at the right time for operator training during the commissioning phase. For the OTS to be an effective training tool, it should be delivered and set up early, preferably during the construction phase.
  • Concerted hard work by instrument and mechanical maintenance staff and DCS engineers in collaboration with the ammonia commissioning manager.
  • The effervescence and high positive energy of the commissioning team could motivate all people to achieve the final objective with success.
  • Consistency and promptness in the procurement of quality critical plant equipment
  • Excellent refractory drying? out of primary reformer, cold collector and secondary reformer ensured the complete absence of hot spots, catastrophic refractory failure, and fouling in waste heat boilers.
  • The shutdowns caused by either spurious trips or equipment problems are converted into opportunity shutdowns to carry out valuable corrective maintenance work.
  • Tube cleanliness is to be monitored more carefully. During catalyst loading, the bottom of the tubes are checked with a borescope to ensure cleanliness. This is a worthwhile activity as there might be debris from the fabrication shop still in the tubes; however, this should be taken care of prior to delivery. New shop inspection procedures are in place to prevent this occurrence in the future.
  • Construction, commissioning and start-up checklists are highly useful. During fast-paced construction activity with so many details to address, it is very possible to miss critical items. Check lists are a useful tool to make sure nothing is overlooked.
  • The workspace is limited. The physical area for installation of the new system might be congested resulting in high work density. Phasing and coordination of work is always key to scheduling, but even more so during the revamp.
  • Having licensor and catalyst field support services is beneficial to construction, commissioning, and start-up activities.


The hot commissioning stage of any new plant is a learning process for everyone involved and unexpected issues usually arise. Frequently, an issue can stem from a misinformed action or reaction to standard phenomena. The key to proactive support is sharing knowledge and experience ahead of time. Sharing experience is the most effective when information is not immediately required. Subsequently when an issue does arise, the operator’s action is instinctive and not reactive. During construction, time could be taken to assess and respond to a situation; but once a plant is online then extra time or slow actions lead to process trips.

Good procedures detail the ‘How’

Good support explains the ‘Why’




  • Ref 1. Commissioning of CIL’s Ammonia II Plant, W. K. Taylor CIL Inc., Courtright, Ontario, Canada, A. Pinto – Imperial Chemical Industries PLC, Billingham, England
  • Ref 2. Commissioning and Start-up of QAFCO 5 and 6, Ali Abdi Jama – Qatar Fertilizer Company (QAFCO)
  • Ref 3. Commissioning of the First Ammonia-Urea Complex A Challenging Venture for the Vietnamese Economy, D. Cimarelli, S. Sridharan Technip Italy, Phung Anh Tuan – Petrovietnam
  • Ref 4. Chemical and Process Plant Commissioning, M Killcross
  • Ref 5. Successful Project Execution and Commissioning of Largest Capacity KRES Ammonia Unit, Timothy Kearns PCS Nitrogen Ohio, L.P., Lima, OH, USA Kim Taniguchi and Akhil Nahar – KBR, Houston, TX, USA, Tim Rembold – Clariant, Louisville, KY, USA
  • Ref 6. Commissioning a world-scale ammonia plant without incident: – Providing Proactive, Not Reactive Support, Daragh Blennerhassett, Johnson Matthey, Alexander Kleyensteiber – thyssenkrupp Industrial Solutions
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