Equipment bottlenecks

Equipment bottlenecks and some insight into the value of debottlenecking... 

Enhancements to the process may be required due to sub-optimal initial design of the equipment, or to implement new technology, or because an idea for improving the production system has emerged. De-bottlenecking would be an example of an... 

As introduced in Section 14.2, bottlenecks in the process facilities can occur at many stages in a producing field life cycle. A process facility bottleneck is caused when any piece of equipment becomes overloaded and restricts throughput. In the early years of a development, production will often be restricted by the capacity of the processing facility to treat hydrocarbons. If the reservoir is performing better than expected it may pay to increase plant capacity. If, however, it is just a temporary production peak such a modification may not be worthwhile. 

Any operation that relies on skills doesn t need a procedure. However, the operator will not be clairvoyant - you may need to provide procedures for straightforward tasks to convey special safety, handling, packaging, and recording requirements. You need to ensure that you don t make your processes so complex that bottlenecks arise when the slightest variation to plan occurs. The setting up of equipment, other than equipment typical of the industry, should be specified to ensure consistent results (see later in this chapter under Verification of job set-ups). In fact any operation that requires tasks to be... 

For catalyst testing, conventional small tubular reactors are commonly employed today [2]. However, although the reactors are small, this is not the case for their environment. Large panels of complex fluidic handling manifolds, containment vessels, and extended analytical equipment encompass the tube reactors. Detection is often the bottleneck, since it is still performed in a serial fashion. To overcome this situation, there is the vision, ultimately, to develop PC-card-sized chip systems with integrated microfluidic, sensor, control, and reaction components [2]. The advantages are less space, reduced waste, and fewer utilities. 

Throughput is in simple terms the average saleable production output per a given time unit. Cycle time is the average time between the release and completion of a job, in other words, the rate at which products are manufactured. Key parameters that affect throughput in a chemical plant include the chemical conversion, yield, capacity and availability of existing equipment, process time, cycle time, number of chemical steps, number of unit operations, plant layout, warehouse processes, raw material availability, process bottlenecks and labour availability, amongst others. 

The volume of the closest standard stirred tanks are 1.6 and 2.5 m while a tray drier of 0.5 m can be assumed standard. The total volume of the equipment is 4.6 m . Since the bottleneck is in stage 1 two units in parallel out-of-phase operation may be considered. The cycle time then becomes ... 

Copper production is quite a complex process to plan and to schedule due to the many process interdependencies (shared continuous casters and cranes, emission level restrictions, limited material availability, to name a few). This makes it very difficult to foresee the overall consequences of a local decision. The variability of the raw material has alone a significant impact on the process, various disturbances and equipment breakdowns are common, daily maintenance operations are needed and material bottlenecks occur from time to time. The solution that is presented here considers simultaneously, and in a rigorous and optimal way, the above mentioned aspects that affect the copper production process. As a consequence, this scheduling solution supports reducing the impact of various disturbance factors. It enables a more efficient production, better overall coordination and visualization of the process, faster recovery from disturbances and supports optimal... 

With regard to specific types of equipment, the safety factor practices of some 250 engineers were ascertained by a questionnaire and summarized in Table 1.4 additional figures are given by Peters and Timmerhaus (References, Section 1.1, Part B, pp. 35-37). Relatively inexpensive equipment that can conceivably serve as a bottleneck, such as pumps, always is liberally sized perhaps as much as 50% extra for a reflux pump. In an expanding industry it is a matter of policy to deliberately oversize certain major equipment that cannot be supplemented readily or modified suitably for increased capacity these are safety factors to account for future trends. 

There are several other factors that are important when it comes to the selection of equipment in a measurement process. These parameters are items 7 to 13 in Table 1.2. They may be more relevant in sample preparation than in analysis. As mentioned before, very often the bottleneck is the sample preparation rather than the analysis. The former tends to be slower consequently, both measurement speed and sample throughput are determined by the discrete steps within the sample preparation. Modern analytical instruments tend to have a high degree of automation in terms of autoinjectors, autosamplers, and automated control/data acquisition. On the other hand, many sample preparation methods continue to be labor-intensive, requiring manual intervention. This prolongs analysis time and introduces random/systematic errors. 

To avoid bottlenecks in the analysis, each step should be automated. Automation of data acquisition is achieved by automated HPLC/UV/MS/ ELSD instruments, equipped with autosamplers that allow compounds to be batch analyzed in unattended fashion. Recently, fast generic HPLC methods have been implemented for analysis of combinatorial libraries [33 53]. 

Brent Pollock (Biomira Inc.) presented a talk on the rational development of a second-generation production process for recombinant human interleukin-2 that incorporates recent advances in cell expression systems, fermentation optimization, protein extraction, refolding, and purification. A key concept of this talk was to know thy protein. The driving forces for process changes were regulatory concerns/robustness, economics, the ability to use standard equipment, and the elimination of bottlenecks in the process. 

With rising feedstock prices and hard competition in the market, many producers have looked for possibilities to revamp or modernize their older, less efficient plants so that they can stay competitive. Most revamp projects have been combined with a moderate capacity increase because some of the original equipment was oversized and only specific bottlenecks had to be eliminated, not entailing excessive cost. As the market possibilities for a company do not increase in steps of 1000 or 1500 t/d but slowly and continuously, such a moderate capacity addition will involve less risk and will often be more economical than building a new plant. 

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