Distributed manufacturing

Hot water basins are used to distribute water in crossflow towers. Here, water is pumped to an open pan over the wet deck fill. The bottom of the pan has holes through which water is distributed. Manufacturers will fit specially shaped plastic drip orifices into the holes to give the water an umbrella shape for more uniform distribution. Different size orifices are used for different flow rates. Ideally, the basin will be almost full at maximum flow. This way, sufficient depth is retained for good water distribution as turn down occurs. The turn down ratio can be extended by the addition of hot water basin weirs- a pattern of baffles perhaps 2... 

Benson and Ponton (1993) and Ponton (1996) have speculated on the ultimate results of continuing efforts for process minimization. They envision a twenty-first century chemical industry totally revolutionized by technological innovation, automation, and miniaturization. Small, distributed manufacturing facilities would produce materials on demand, at the location where they are needed. Raw materials would be nonhazardous, and the manufacturing processes would be waste free and inherently safe. While their vision of future technology is speculative, we are beginning to see progress in this direction. 

Koch, T. A., K. R. Krause, and M. Mehdizadeh (1996). Improved Safety Through Distributed Manufacturing of Hazardous Chemicals. 5th World Congress of Chemical Engineering, July 14-18, 1996, San Diego, CA, Paper 52a. New York American Institute of Chemical Engineers. 

Distributed Manufacturing - A Conceptual Study of Future Scenarios... 

As a possible chemical process for distributed manufacture, the production of toxic feedstock gases is claimed [1,139]. Benson and Ponton were among the first... 

Benson and Ponton propose, based on this analysis, the concept of distributed manufacturing [139, 145], which will be referred to in detail in Volume 2 of this book series. Basically, they refer to small, transportable plants which are fed with reactants over the fence , hence using only non-hazardous, generally available materials by normal piping or standard transport. If an aggressive chemical is needed, it has to be made from environmentally friendly base materials as an intermediate on-site. Needless to say, effluents have to be completely harmless, plant operation has to be intrinsically safe, and the plant should be clean and quiet. 

Small but environrrientallyjnendly. The Chemical Engineer, March 1993 Huge increases in technology in the past distributed manufacturing in small-scale plants miniaturization of processes domestic methanol plant point-of-sale chlorine simpler and cheaper plants economy of plant manufacture process control and automation start-up and shut-down sensor demand [145],... 

Points 1 and 5 refer to the increased importance of functional chemicals [291]. Owing to the wide parameter space determining functionality (not only molecular diversity), this demands much higher flexibility and speed in the preparation of new samples during the research phase. The behavior of complex molecular mixtures needs to be understood. In particular, product application, formulation, and blending skills need to be developed and acquired. In a more remote vision, this demands on-site distributed manufacture of functional chemicals such as paints and similar products. 

Following a theoretical analysis of distributed small-plant manufacture, Benson and Ponton define assessment criteria for processes suitable for such processing [139]. Since micro reactors are one of the favorite and natural tools for distributed manufacture, this selection list also defines micro-reactor applications. In this context, the authors, probably in one of the first regular citations, emphasize that formulation processes, especially those with multiple ingredients, are particularly suited for distribution. The making of paint on-site is referred to as an already existing way to do so. It stands to reason to augment the scope from formulations to functional chemicals. 

Key Performance Indicators (KPIs) in supply chain balanced scorecards and performance management are one example for analysis methods. Beamon (1998) and Chan (2003) distinguish qualitative performance measures such as customer satisfaction, on-time delivery, fill rate or flexibility as well as quantitative measures based on costs in distribution, manufacturing and inventory or warehousing. 

On the aesthetic side, it is likely that intensified process plants will be less intrusive on the environment, making them far less of an eyesore than the unsightly and massive constructions that are characteristic of present processing units. In some cases the plant may be mobile, thereby offering the opportunity for distributed manufacturing of chemicals close to the point of utilisation. This may reduce the quantities of hazardous products currently being transported by road and rail, thereby improving safety. The... 

Koch, T.A., Krause, K.R. and Mehdizadeh, M., Improved safety through distributed manufacturing of hazardous chemicals, Process Safety Prog. 1997, 16(1), 23-24. 

In 2000, the UCR estimated 1.6 million arrests for drug violations in the United States among all age groups. The UCR defines drug violations as state and/or local offenses related to the unlawful sale, purchase, distribution, manufacture, cultivation, possession, or use of a narcotic drug. These reports consider marijuana a narcotic drug. 

Evaluate granulation particle size distribution Manufacturability Particle size analysis or powder flow assessment Powder flow... 

In later discussions in this book it should be noted that migration behaviour is strongly dependent on the given polymer sample. This dependency comes from the variety of plastics that exist with respect to their chemical nature, structure, molecular mass distribution, manufacturing and processing conditions. 

Although natural gas is the predominant product (98%) of the gas industry today, its utilization evolved out of the production and use of manufactured gas, and its major expansion came about through utilization of early town gas systems originally installed to distribute manufactured gas. 

Long term, it will even be possible to manufacture many hazardous materials in plants as small as a silicon chip, using large numbers of plants on a chip in parallel to produce the quantity of material required [61, 62]. It is unlikely that the large, world-scale petrochemical plant vdll ever completely disappear. However, distributed manufacture of chemicals in small plants will become an important part of the industry, in particular for the improved safety through distributed manufacturing of hazardous chemicals. There are many relevant examples besides those cited previously of phosgene and methyl isocyanate synthesis, for example HCN [63] and aqueous peracetic acid [64] on-demand syntheses. 

On the other hand, a distributed manufacture, based on either on-site small reforming plants or on small-size electrolyzers, would permit storage at the vehicle facility and strongly reduce the specific impact of fuel distribution and transport costs on a global techno-economic assessment. 

Fundamental resource limitations Recycleability Geopolitical distribution Manufacturing, R D Cycle life... 

With regard to the environment, the intensified plant of the future will be much less obtrusive, with the distillation and absorption towers of our present chemical complexes being replaced by more compact and inconspicuous equipment, which may be hidden by the boundary tree line. In addition, the cost of effluent treatment systems will be less, allowing tighter emission standards to be reached economically. The economic incentive to produce commodity chemicals in large centralised plant complex is likely to diminish or disappear with the application of PI. Thus distributed manufacture in smaller plant will be both feasible and economic, thereby avoiding the need to distribute hazardous material on the public transport system. 

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