Shutdown planning should begin 9 to 18 months before the anticipated shutdown is to take place. Seven areas: procurement, engineering, maintenance, operations, quality assurance, HSE & security, and administration will have activities that can be executed during this planning period. To ensure these shutdown planning activities are tracked and completed, they should be included on the master execution schedule.
Minimizing the duration of the outage can have a major impact in reducing the cost of lost production. Process Technical Services can provide qualified and experienced personnel to augment the resources available to handle shutdown planning and scheduling, manage the shutdown activities, and assist in the startup of the facilities to minimize the out-of-service time.
Shutdowns can be costly in terms of lost production, so a carefully designed plan can reduce costs. In many respects a shutdown can be even more complicated than the initial construction of the facility. Not only must the facility in the end be reassembled and the work carefully reviewed before startup, as it was when construction was completed, it must first be shutdown, cleaned up, and partially disassembled in order to restore its original functionality. Consideration must be given to the impact on both upstream and downstream processes, and the impact on customers and suppliers.
Shutdown planning in the chemical industry can differ substantially from the shutdown planning refineries undertake. In many respects chemical plant operation is simpler than refinery operations. A chemical plant generally consists of a synthesis operation, followed by a refining and purification operation. With the emphasis that has been placed on building large, single-line chemical plants over the past fifty years there are usually no parallel operations that can continue in operation. Under these circumstances, both the synthesis and refining operations are shutdown together.
Refinery operations are considerably more complex. Simply stated, a refinery receives a single complex feedstock, crude oil, which is separated into multiple product streams. There may be several different reaction-refining operations being conducted on the site, anyone of which could possibly be involved in a shutdown with minimal impact on the operation of other operations.
With very large refineries, it is impractical to shut down the entire facility at one time. There is usually far more work to be done, than manpower available to do it. Thus, refineries often sequence the shutdown of the units to undergo work.
Shutdown planning begins with specification of the work to be done on each unit operation. This work can include inspection and testing of critical components, such as relief valves, repairs and replacement of damaged or worn-out parts, or a project to improve or expand the capacity of the plant.
Often, the true condition of the equipment is not fully known until it has been cleaned and inspected. There are uncertainties that must be considered during the shutdown planning process and a determination should be made as to the extent contingency plans should be developed.
Once a complete scope of work has been developed that includes each of the unit operations, then the materials, manpower, and duration of the work can be determined for each of those units. This provides the basis for procuring materials and services, and providing the necessary manpower to complete the work in a reasonable period of time. A key manpower consideration involves work scheduled at other nearby plants. These other plants with their shutdowns will be drawing from the same manpower pool.
At one time or another all operating units must shutdown to upgrade or recondition equipment, conduct tie-ins, or make inspections or repairs. Many times these events present more challenges because experienced personnel may be limited. Teaming with Process Technical Services can help make your shutdown be on time, within budget, and back in operation safely and efficiently. Our competent personnel know how to put the pieces together to insure a successful shutdown.