22 Jan 2018

A coal fired power station based in the UK decided to invest in NOx emission improvements to work towards compliance with the Industrial Emission Directive and allow a wide diet of fuel types including high volatile content coal. This new coal diet brought safety challenges for the mature power station and additional explosion protection measures were required for the mills and classifier processes.

The power station owner executed a rapid, rigid and rather extensive tender process – requesting a single value turnkey tender package with strict technical / performance compliance along with a challenging timeframe to have the systems installed, commissioned and operational in three phases throughout within 12months.

Explosion protection system

The explosion protection system proposed by IEP was a design to address the challenging environment

This is where the IEP teams proved muster. With detailed quality procedures, testing protocols, manufacturing plans, project plans, health and safety control and engineering requirements being a pre-requisite to comply with the Invitation to Tender, the global and multidisciplinary IEP team, pooled their resources and knowledge to deliver a full tender package within a few working days.

The explosion protection system proposed by IEP was a bespoke design to address the challenging environment and application to provide a comprehensive protection solution to the 18 ball mill and classifier processes. This process involves delivering raw coal to a ball mill, which pulverizes the coal into a fine powder and then passed through a classifier (to remove remaining large particles) and onto the burners on the boilers. The proposed solution - and moreover IEPs understanding behind the protection concept led to the contract being awarded to IEP.

Dynamic explosion detection technology

Key elements of success were:

  • Expert understanding of proposed solution in terms of flame propagation, explosion mitigation and application to plant.
  • High resistance to false alarms/activation, brought about by IEP Technologies’ unique dynamic explosion detection technology
  • System performance and reliability – in particular the basis behind claim Safety Integrity Level 2 (SIL2) for the system.
  • The track record with protecting coal milling plants
  • Quality assurance and certification
  • Full and timely response to the Invitation to Tender

IEP suppression system

The high quality of IEP Technologies’ bid, being fully technically and commercially compliant to the Tender in a very short period of time, backed up with a comprehensive level of response to detailed technical scrutiny, won the day.

The installation and commissioning work was completed on time and all phases of the test and handover successful. Within 6 weeks of the power station running on the new volatile diet, the IEP suppression system was called into action with all indications showing that a relatively strong explosion event was successfully mitigated, protected people and plant as intended. Another great success story for the IEP team.