Online advanced process control

Advances in hydroprocessing are driven by competitive forces and clean-fuel regulations. These advances include improved catalysts (Chapters 9-11), better reactor design (Chapters 7-8), advanced process control (Chapter 22), and online optimization (Chapter 23). As clean-fiiel regulations migrate from North America and the EU into the rest of the world, and as globalization of the oil industry continues apace, the need will continue for new (and better) hydroprocessing units. Hopefully, within a few years, this chapter will be obsolete and we ll have to write an update. 

Instrument manufacturers offer a variety of devices, including monitoring systems for standard process or for spot curing technology and systems for process control. Online UV radiometers can measure and display the peak intensity and total UV energy used in the process. More-advanced systems map the entire process and evaluate the lamp focus, reflector focus and reflector efficiency within a specific... 

Recent developments in ECM practice have dwelt on the replacement of constant direct current by pulsed current. The key to further advancement lies in the development of a low-cost power supply. Successful development of technique will enable online monitoring of gap size, enabling closer process control. 

It is important to emphasize that the development of fiber optics technology is a fundamental cornerstone that allowed for the development of real in-line and in-situ monitoring spectroscopic techniques, as the sampling device can be placed at very harmful environments, while the spectrometer still sits in a process control room. Without the support of fiber optics technology, samples have to be prepared and placed inside the illuminated chambers (as performed in the lab since the nineteenth century) or pumped through sampling windows (as performed in advanced systems intended for process and product development, such as automatic continuous online monitoring of polymerization reactions (ACOMP) [37- 1] in order for spectral data to be obtained. 

Extensive work has been done to build models around standard process data as well as other types of online data such as online melt flow index, bulk viscosity, and so on the primary goal of these is to attempt to infer polymer properties to enable better process control [22-26]. Generally, much of the model building work is done off-line to determine optimal operating poUdes and optimal process variable trajectories that define end-product quality and reaction yield. Several types of advanced software have also been developed toward this goal [27,28]. There is more discussion of process control theory and application in other chapters of this book, especially Chapters 16-18. 

Supply capability is reviewed in the advanced levels with respect to the firm s core competencies and its value chain partners, and decisions made as to which partner should perform which process steps. In the most advanced levels, flexible response systems that do not interfere with overall supply chain efficiency are created. There is much lower variability in the network as all parties work together through an online extranet to instantly review what is occurring and where changes must be made. Constraints in the system are eliminated or under control as the end-to-end partners link their ERP systems in order to make visible what is occurring across the full network. 

A spectrum of synthetic water-soluble polymers is available and utilized daily in areas such as the production of energy, clean water, and industrial and personal care products that enhance our quality of life. It is hard to imagine what our world would be like without than. Advances continue to be made in the areas of new polyma design, production, and in the instrumentation and methods utilized for monitoring polymerizations. There is unlimited opportunity for researchers in academia and industry alike to develop and utilize cost-effective monitoring tools in water-soluble polyma production. Increased use of online monitoring tools at the commercial-scale will allow for improved production efficiency, reduced product variability, and the accommodation and tighter control of more complex processes. 

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