Inventories, lower

Directed toward reduced inventories, lower numbers of batch failures, and efficient batch release (QA/QC). 

Kletz, Trevor A., Plant Design for Safety—A User-Friendly Approach, Hemisphere, New York, 1990. Kletz s easy-to-read, short book argues that additional safety can be achieved with safer substitute materials, lower inventories, lower temperatures, and lower pressures. 

Liquid inventory. With unstable chemicals, minimizing liquid inventories at hot temperatures minimizes product loss due to degradation and decomposition reactions. In batch distillation, excessive liquid inventory lowers product recovery. With hazardous chemicals, minimizing liquid inventories lowers the hazard. 

Advantages of use of precompounded materials shorter cycle smaller inventory lower employment smaller investment. 

After the implementation, Valvex benefited from increased accuracy of inventory, lower... 

Inventory—Inventory masks many of the problems in a business. It is like an insurance policy. Equipment breaks—it is okay we have inventory. Suppliers deliver late—it is okay we have inventory. Employees report off—it is okay we have inventory. Lowering inventory levels forces a company to address all of these and other problems. 

Inventory Lower costs because of aggregation. Benefits of aggregation are highest for iow-demand, high-vaiue items. Benefits are large if product customization can be postponed at the manufacturer. 

Distillation. There is a large inventory of boiling liquid, sometimes under pressure, in a distillation column, both in the base and held up in the column. If a sequence of columns is involved, then, as discussed in Chap. 5, the sequence can be chosen to minimize the inventory of hazardous material. If all materials are equally hazardous, then choosing the sequence that tends to minimize the flow rate of nonkey components also will tend to minimize the inventory. Use of the dividing-wall column shown in Fig. 5.17c will reduce considerably the inventory relative to two simple columns. Dividing-wall columns are inherently safer than conventional arrangements because they lower not only the inventory but also the number of items of equipment and hence lower the potential for leaks. 

The column inventory also can be reducdd by the use of low-holdup column internals, including the holdup in the column base. As the design progresses, other features can be included to reduce the inventory. Thermosyphon reboilers have a lower inventory than kettle reboilers. Peripheral equipment such as reboilers can be located inside the column. ... 

It is easy to say that operation of a reactor at higher temperature might lead to a safer plant if the inventory can be reduced as a result, but how do we assess such changes quantitatively Lowering the inventory makes the plant safer, but raising the temperature makes it less safe. Which effect is more significant ... 

Use the divided wall column shown in Fig. 5.17c to reduce the inventory relative to two simple columns, and reduce the number of items of equipment and hence lower the potential for leaks. 

The annual United States import of vanilla beans jumped 34% in 1991, as importers and users replenished inventories (7). Indonesia was the largest suppher, accounting for 47% of the total the lower price for Indonesian beans is responsible for the increase in shipments. Users have been replacing Bourbon beans with Indonesian types, or blending in Indonesian beans, because they may still label their product as natural and meet other EDA specifications. 

The turbulent fluidized bed has a similar or slightly lower soHds volume fraction than the vigorously bubbling bed. There is considerable transport of soHds out of the turbulent bed and the bed level is not very distinct. Large-scale cyclones are needed to return soHds to the bed. On average, the bed inventory passes through the cyclones several times per hour. 

Perhaps the biggest contribution that technological advancement in petroleum production will make is bringing large volumes of unconventional petroleum resources, eg, heavy oil and tar sands, into a viable economic realm by lowering the unit cost of production. Compared to the inventory of conventional petroleum reserves and undiscovered resources, the physical inventories of such unconventional petroleum resources are extremely large for example, the Athabasca tar sands in Alberta, Canada, are estimated to contain 360 x 10 m (2250 x 10 bbl) of in-place petroleum (19). This volume is equivalent to the total inventory, ie, the combined cumulative production, reserves, and undiscovered resources, of world conventional cmde petroleum. In... 

Most people agree that general expenses incurred in administration, selling, distribution, etc., should not be included in the cost of inventory. In fact, many feel that no costs should be absorbed before they have been incurred. In general, method 2 is favored by engineers and method 3 by most accountants. However, the accountancy convention is to value at either cost or market value, whichever is the lower. In the methods considered, either ac tual or standard costs can be used. Note that method 3 shows a higher profit than method 2 when sales volume exceeds the produc tion rate and a lower profit when the production rate exceeds sales volume. 

Thus, in a time of rising raw-materials prices, the FIFO method gives a higher value for the remaining inventory than will LIFO. In a time of falling prices, the FIFO method will give a lower value for the remaining inventory than will LIFO. 

Inherent safety Inventory reduction Fewer chemicals inventoried or fewer in process vessels. Chemical substitution Substitute a less hazardous chemical for one more hazardous. Fr ocess attenuation Use lower temperatures and pressures. 

Similarly, hazardous raw material storage should also be minimized, with greater attention being given to just in time supply. Inventory reduction lowers inventory costs, while increasing inherent safety. In determining appropriate raw material inventories, the entire raw material supply chain must be considered. Will the supplying plant have to increase inventories to provide just in time service, and will... 

Basic process chemistry using less hazardous materials and chemical reactions offers the greatest potential for improving inherent safety in the chemical industry. Alternate chemistry may use less hazardous raw material or intermediates, reduced inventories of hazardous materials, or less severe processing conditions. Identification of catalysts to enhance reaction selectivity or to allow desired reactions to be carried out at a lower temperature or pressure is often a key to development of inherently safer chemical synthesis routes. Some specific examples of innovations in process chemistry which result in inherently safer processes include ... 

Synthetic rubber latex was made by a process with a large and hazardous inventory of butadiene and styrene. In a modified process, the reactor has an initial charge of water and emulsifier. Also, the monomers are added to the reactor as one premixed stream and the emulsified aqueous sodium persulfate is added as the other stream. The improved scheme, discussed by Englund (1991a) contains less hazardous material and at a lower, more controllable temperature. It illustrates that large and established processes may be made safer by applying inherent safety. 

The pressure vessel is 79 ft high with an upper diameter of 23 ft and lower diameter of 20 ft. This height is key to establishing natural circulation core flow by providing a chimney in the space between the top of the core and the steam separator assembly. This large top diameter increases the water inventory above the core (no accumulators needed), and the smaller lower diameter reduces the volume of water needed to be replaced to provide core cooling. 

Labor cost in a structure is directly related to part count. If part count can be reduced, then labor costs (and inventory costs) wili decrease. Composite structures are generally composed of many fewer parts than are metal structures. Integral part design and fabrication techniques reduce fastener count and bonding operations. Thus, composite structures can have cost elements that are considerably lower than those for metal structures. 

A technology agreement was made by Duracell/Toshiba/Varta in 1992, strategically aimed at the portable computer field. In 1994 a joint venture, "The 3 C Alliance" was formed. Standardization of the inventory was the main point. The benefits were seen to be easier replacement and lower cost per unit ( 170 for 6 h ). One of the first commercial partners was Compaq Computer Co. 

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