Processing facilities size considerations

The ferrous metals industry is a major contributor of lead emissions to the atmosphere (see emission inventory. Chapter 2). The industrial raw materials are not rich in lead, but as a consequence of the massive size of the industry, and the high process temperatures used, considerable emissions of lead result. In 1975, it is estimated that in the US, 1770 tonnes of lead were emitted to the atmosphere in the production of ferrous metals and alloys 605 tonnes from iron and steel plants, 1080 tonnes from gray iron foundries and 82 tonnes from ferroalloy production facilities, excluding fugitive emissions [1]. 

A further consideration is that boiler plants operate most effectively when the FW and BW chemistry is constant and predictable. Thus, irrespective of a facility s size (or lack of size), a key objective should be to produce FW of a consistent composition. Pretreatment equipment processes can often be particularly useful in ironing out variations in the quality of both MU and CR. 

Facility design is also an important consideration in process design and scale-up. An important observation to be made up-front is that the market size for biologies bears little correlation with the size or volume of production (Table 4). 

Adjusted hours are the home office hours that would be required by a large engineering contractor to perform a specific scope of work for a plant with normal sized equipment. They are derived from the base hours, adjusted to take into consideration the specific situation e.g., extent of process design required, type of process and instrumentation, special site conditions, extra retrofit work, existing facilities. Owner s participation, etc. 

Produced from Coal. Estimates of the cost of producing methanol from coal have been made by the U.S. Department of Eneigy (DOE) (12,17) and they are more uncertain than those using natural gas. Experience in coal-to-methanol facilities of the type and size that would offer the most competitive product is limited. The projected costs of coal-derived methanol are considerably higher than those of methanol produced from natural gas. The cost of the production facility accounts for most of the increase (11). Coal-derived methanol is not expected to compete with gasoline unless oil prices exceed 0.31/L ( 50/bbl). Successful development of lower cost entrained gasification technologies could reduce the cost so as to make coal-derived methanol competitive at oil prices as low as 0.25/L ( 40/bbl) (17) (see Coal conversion processes). 

It may be a long process between the removal of the irradiated target from the irradiation facility and the pure radiochemical substance or compound to be used in some experiment. The separation procedures needed to make a pure radiation source are chemically the same and (usually) independent of the "size" (i.e. its total radioactivity), but the experiments become more cumbersome — and often slower — when the radiation source is so large as to require considerable shielding. 

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