PLANT START

Fig. 2. (— —) Cumulative and (—° —) 8% discounted cash flow rate for development of a hypothetical agrochemical in constant 1994 U.S. dollars, where A represents the time the patent was first issued B, first registered use C, manufacturing plant start-up D, positive cumulative cash flow and E, patent...

Pilot-plant start-up is different from principal process plant start because of the smaller scale of the unit, smaller resources committed, lack of advance start-up planning, and limited experience with the pilot-plant process and operation. 

Pilot-plant start-up costs vary widely. The costs booked to the start-up as well as the extent of the commissioning activities labeled as "start-up" vary... 

Uniform, rehable flow of bulk soflds can allow the production of quaUty products with a minimum of waste, control dust and noise, and extend the hfe of a plant and maximi2e its productivity and output. By conducting laboratory tests and utili2ing experts with experience in applying soflds flow data, plant start-up delays that can impact schedule and cost can be eliminated. 

In 1956, the world s first commercial nuclear power plant started operation in England. By the 1960s, many nuclear power plants were built worldwide. At the end of the twentieth century, nuclear generating plants are used widely by U.S. electric utiHties. Since 1984, these plants have provided the second largest share of total U.S. electricity generation, 21% of annual GW-h generated, behind coal-fired power plants (see Nuclearreactors). 

The semiregenerative procedure for catalyst regeneration varies slightly between catalyst vendors however, it typically follows these general steps plant shutdown, carbon bum, oxidation and chlorination, nitrogen purge, reduction, and plant start-up. During the plant shutdown, Hquid hydrocarbons... 

Commercial scale plant started up in the spring of 1988 purifying a bulk chemical. This is the first application of the CCCC process on this bulk chemical. 

Attempts to produce coplymers of ethylene and styrene by free radical and by conventional Ziegler-Natta catalysts systems have, over the years, not proved successful. However, in 1998 Dow announced novel polymers using a metallocene process with the intention of commercial polymerisation using a 23 000t.p.a. capacity plant starting in 1999. 

When flammable materials are used, drain valves should not be located above hot pipework or equipment. A fire on an ethylene plant started when a mixture of water and naphtha was drained through a )4-in. drain valve onto pipework at 315°C. It took a long time to replace damaged control and electric cables [21J. 

Unfortunately the address of the gateway in the control computer used for the data transfer was the same as that used to connect to the distributed control system (dcs). As a result data flowed from the simulator through the control computer to the dcs and replaced the current input data by historic data. Some conditions on the plant started to change, but fortunately this was soon noticed by alert operators, and the plant was brought back under control. 

On many occasions, long hours of work are required because the worker may have to stay on duty at the end of the shift to fill in for someone on the next shift or because there are plant start-up or shutdown operations. 

Steroids not readily accessible by modification of plant starting materials, for example, those possessing unusual substituents at the angular positions, are made available by total synthesis. 

Alkali-promoted Ru-based catalysts are expected to become the second generation NHs synthesis catalysts [1]. In 1992 the 600 ton/day Ocelot Ammonia Plant started to produce NH3 with promoted Ru catalysts supported on carbon based on the Kellogg Advanced Ammonia Process (KAAP) [2]. The Ru-based catalysts permit milder operating conditions compared with the magnetite-based systems, such as low synthesis pressure (70 -105 bars compared with 150 - 300 bars) and lower synthesis temperatures, while maintaining higher conversion than a conventional system [3]. 

OS 68] [R 19] [P 50] A numbering-up of five mini mixers, tested at the pilot stage, was used [134]. Automation of the entire process was required liquid-flow splitting to the single reactors was ... by no means trivial... [134]. The capacity of one mini reactor was 30 ml s , i.e. 1081 h . The complete setup hence should be operated close to 5001 h . The micro-reactor plant was operated at intervals as the preceding step was carried out batchwise. The operation of the micro-reactor plant started in August 1998 after a period of only about 1.5 years for development. 

Although continuous stirred-tank reactors (Fig. 3.12) normally operate at steady-state conditions, a derivation of the full dynamic equation for the system, is necessary to cover the instances of plant start up, shut down and the application of reactor control. 

Hexamethylenediamine (HMDA), a monomer for the synthesis of polyamide-6,6, is produced by catalytic hydrogenation of adiponitrile. Three processes, each based on a different reactant, produce the latter coimnercially. The original Du Pont process, still used in a few plants, starts with adipic acid made from cyclohexane adipic acid then reacts with ammonia to yield the dinitrile. This process has been replaced in many plants by the catalytic hydrocyanation of butadiene. A third route to adiponitrile is the electrolytic dimerization of acrylonitrile, the latter produced by the ammoxidation of propene. 

As of 1990, seven industrial-scale plants were operating in Russia (Bunimovich et al., 1990). The first plant started up in 1982. The design of these plants generally follows the schematic given in Fig. 7. Some employ an intermediate heat exchanger, but details have not been published. Designs are marketed around the world by several organizations. 

Where it is necessary to follow a fixed sequence of operations—for example, during a plant start-up and shut-down, or in batch operations — interlocks are included to prevent operators departing from the required sequence. They may be incorporated in the control system design, as pneumatic or electric relays, or may be mechanical interlocks. Various proprietary special lock and key systems are available. 

Information on manufacturing processes, equipment parameters, materials of construction, costs and the physical properties of process materials are needed at all stages of design from the initial screening of possible processes, to the plant start-up and production. 

In addition to the above subcategories, porcelain enameling on continuous strip is a subdivision within this industry. However, because there are only two plants in the U.S. producing this product, a separate subcategory is not necessary. These plants start with coils of steel, aluminum, or aluminized steel, porcelain enamel them and either recoil them for sale to metal fabricators or shear them into pieces for use as architectural panels or chalkboards. The estimated production was 2.0 x 106 m2 (22 x 106 ft2). This figure represents the area of enamel applied. For multiple coats, the area for each coat is considered. 

D Modes of plant start-up, shutdown, construction, inspection and maintenance, trigger events and... 

Pressure-relieving systems are unique compared with other systems within a chemical plant hopefully they will never need to operate, but when they do, they must do so flawlessly. Other systems, such as extraction and distillation systems, usually evolve to their optimum performance and reliability. This evolution requires creativity, practical knowledge, hard work, time, and the cooperative efforts of the plant, design, and process engineers. This same effort and creativity is essential when developing relief systems however, in this case the relief system development must be optimally designed and demonstrated within a research environment before the plant start-up. 

The process was developed by Du Pont in the 1940s and its first plant started operating in 1958. It has progressively replaced the older Sulfate Process because it produces less effluent in 1998, 56 percent of the world capacity for titanium dioxide production used the Chloride Process. See also ICON. 

Experience has shown plant start-ups to be difficult and that it takes time for capacities to reach critical mass. 

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