Shutdown objectives

As a result of these poorly designed control systems, users experience significant operational problems, including machine and process shutdowns. As with any process plant, the first objective is to achieve reliable production from the FCCU. Only with reliable production will operators start optimizing the unit. Users, therefore, are not using the... 

Technician leaves an object on the rail Moveable assembly cannot move Could be high Object must be located close to a wheel on the side toward the movement. Even slight movement may shutdown assembly. 

The main objective of a shutdown is to accomplish, at the lowest possible costs, the maximum quality and quantity of work that can be completed within a limited time, defined as the outage. Shutdown activities should be concentrated on work that can only be performed during shutdown or when production systems are idle. A well-organized and adequately planned and scheduled shutdown is the best insurance for lower maintenance and high reliability of equipment. 

Developing new chemical engineering design tools to deal with the multiple objectives of minimum cost process resilience to changes in inputs minimization of toxic intermediates and products and safe response to upset conditions, start-up, and shutdown. 

The technical architecture Apackage structure (for static dependencies) and collaborations (across technology components, such as UI, business object servers, and databases). These cover all domain-independent parts of the system hardware and software platforms infrastructure components such as middleware and databases utilities for logging, exceptions, start-up, and shutdown design standards and tools and the choice of... 

Preventing cascading events due to loss of control of process units not involved in the event is another objective of blast resistant design. An incident in one unit should not affect the continued safe operation or orderly shutdown of oilier units. 

Success stories can show that improved process safety can contribute to increased productivity, cost efficiencies, and reliability. Using metrics to demonstrate the nexus between process safety performance and other organizational objectives only serves to reinforce individual and organizational commitments to process safety. A good process safety system, including appropriate metrics, can help prevent events such as unplanned shutdowns. Decreasing the number of unplanned shutdowns due to equipment failures or processing aberrations are examples of where process safety and other operational activities are linked. Unplanned shutdowns create extra cost and production problems as well as increase the probability of a process safety incident. 

The performance requirements can be represented either by constraints or by a contribution to the operating costs. In some cases, this is straightforward-equipment and material and energy inputs can be included in an economic objective constraints for which violation leads to plant shutdown are well approximated by a hard constraint. In other cases, the choice of representation is more difficult—excessive quality variations may lead to complete loss of the market for a product (constraint) or reduced price for the product (objective). 

Clay was added at the stoichiometric quantity needed for the sodium reactions and the ratios to MSW and DSS were 0.0235 g/g as-received MSW and 0.25 g/g dry DSS. During the run, considerable difficulty with the MSW feed system was encountered. Upon shutdown and inspection of the MSW, it was found that large metallic objects were present in the hopper and screw and were probably hindering the MSW feed to the combustor. 

The objective of minimizing scale formation was met because no significant build-up of sand or other materials could be detected in the combustor, external boiler, piping, and cyclones after shutdown and inspection. The problem of agglomeration and build-up was apparently minimized by the addition of clay. 

In large-diameter columns, when shutdown time is critical, and if manhole location permits, two tray installation crews are often used simultaneously inside the column. This practice suffers from the hazards of falling objects and/or poor ventilation and should be avoided whenever possible. If it has to be used, precautions are required for minimizing the risks. 

Once the column is bolted up (either after initial construction or after a shutdown), a number of operations are performed to prepare it for startup. This phase is often referred to as column commissioning. The main objectives of column commissioning are to clear the system of undesirable materials, to test the column and rectify potential problems, and to take preventive measures against performance deterioration (e.g. due to fouling). 

This very comprehensive process is a component of CRl. It is conducted for critical assets and, typically, discrete manufacturing equipment. The objective is to maximize the capability of the asset to perform its primary functions. It takes a complete look at the requirements for maintenance, setup, operations, changeover and shutdown, and documents these into standard operating and maintenance procedures. The results of a typical asset-facilitation process would include the following ... 

---