Sources of raw materials

The eady juice industry was largely a salvage operation. The principal source of raw material was misshapen, poorly colored, or skin blemished fmit unsuitable for the fresh, canned, or frozen fmit market. In the 1990s, raw materials are selected for suitabiUty for juice production, except for apple juice production which still uses much cull fmit (4). 

Methane. As our most abundant hydrocarbon, methane offers an attractive source of raw material for organic chemicals (see Hydrocarbons). Successful commercial processes of the 1990s are all based on the intermediate conversion to synthesis gas. An alternative one-step oxidation is potentially very attractive on the basis of simplicity and greater energy efficiency. However, such processes are not yet commercially viable (100). 

Aliphatics. Methane, obtained from cmde oil or natural gas, or as a product from various conversion (cracking) processes, is an important source of raw materials for aliphatic petrochemicals (Fig. 10) (see Hydrocarbons). Ethane, also available from natural gas and cracking processes, is an important source of ethylene, which, in turn, provides more valuable routes to petrochemical products (Fig. 11). 

Other industries that are traditionally located close to the source of raw materials include the steel (qv) industry, located close to iron ore the flour industry, close to wheat fields the meat-packing industry, close to gracing land for catde pulp and paper, close to forests and the mining industry, close to mines. The inorganic industry, including salts, ash, borax, and gypsum, has always been located near the source of the needed raw material. 

Aluminum sulfate is a starting material in the manufacture of many other aluminum compounds. Aluminum sulfate from clay could potentially provide local sourcing of raw materials for aluminum production. Processes have been studied (24) and the relative economics of using clay versus bauxite have been reviewed (25). It is, however, difficult to remove impurities economically by precipitation, and purification of aluminum sulfate by crystallization is not practiced commercially because the resulting crystals are soft, microscopic, and difficult to wash effectively on a production scale (26—28). 

The major source of raw materials for the preparation of fatty amines is fats and oils such as tallow, and coconut, soya, and palm oils. Ethyl Corporation uses petrochemicals as raw materials to prepare alkyl dimethyl and dialkylmethyl tertiary fatty amines, trademarked as AE)MA and DAMA products, which can be suppHed as single-carbon chain-length cuts or custom blends (13). Commercially available high purity fatty amines are Hsted in Table 3. Cost of the amines can vary owing to supply of raw materials. 

The oil-fiimace process, based on the partial combustion of Hquid aromatic residual hydrocarbons, was first introduced in the United States at the end of World War II. It rapidly displaced the then dominant channel (impingement) and gas-furnace processes because it gave improved yields and better product quahties. It was also independent of the geographical source of raw materials, a limitation on the channel process and other processes dependent on natural gas, making possible the worldwide location of manufacturing closer to the tire customers. Environmentally it favored elimination of particulate air pollution and was more versatile than all other competing processes. 

Sources of Raw Materials. Coal tar results from the pyrolysis of coal (qv) and is obtained chiefly as a by-product in the manufacture of coke for the steel industry (see Coal, carbonization). Products recovered from the fractional distillation of coal tar have been the traditional organic raw material for the dye industry. Among the most important are ben2ene (qv), toluene (qv), xylene naphthalene (qv), anthracene, acenaphthene, pyrene, pyridine (qv), carba2ole, phenol (qv), and cresol (see also Alkylphenols Anthraquinone Xylenes and ethylbenzenes). 

Once the volume of raw material is set. the price must be estimated. In some studies, a captive source is available with a set transfer price. In other studies, contracts for raw materials will be far enough along to establish the price. However, in some studies, contacts with vendors and the literature is the only source of raw material prices. 

With each succeeding year in the 1950s and 1960s there was a swing away from coal and vegetable sources of raw materials towards petroleum. Today such products as terephthalic acid, styrene, benzene, formaldehyde, vinyl acetate and acrylonitrile are produced from petroleum sources. Large industrial concerns that had been built on acetylene chemistry became based on petrochemicals whilst coal tar is no longer an indispensable source of aromatics. 

For many processes, one or more predominant factors effectively minimize the number of possibilities for plant location. Raw material and transportation costs may be such that a plant must be located near a source. Thus, only the sites near to sources of raw material need be studied and these may be few in number. Similarly, labor requirements may be hear y enough to eliminate cities below a certain size. These and other factors serve as effective screening agents that save both time and money. 

Although the source of raw materials may not be at the plant site, it is an e.xtremcly important factor in the ultimate location of the plant. Process development work and economic studies will indicate the minimum standards for raw materials selection. When these standards have been determined, all possible sources of acceptable raw materials can be located and a detailed analysis can proceed. 

Although chemistry as an emperical fundamental didpline has a long history, its application in industry gained importance after the introduction of the use of fossil energy sources during the industrial revolution. The chemical industry withdraws non-renewable materials, mainly fossil oil, from the earth s reserves to use as an energy source and as fossil oil a source of raw materials for production processes. The products so produced are rather... 

One of the problems that face our civilization is the fact that the pressure on natural resources is reported to be hindering progress. Periodically an energy crisis exists that has led to a so-called materials crisis in plastics and even other materials such as cellulose papers. Petroleum is currently the major source of raw materials for most high volume plastics. 

Petroleum is currently the major source of raw materials for most high volume polymers. Also used are gas and substitute resources such as coal that are supposedly in limited supply (although our government reports we have enough coal for the next 250 years that includes its growth expansion in use during that period), and it may well be that another approach to the problem is required. An example is different raw material sources to produce plastics that involve biotechnology (186). 

Are all raw materials used onsite documented in an inventory Provide a schedule and identify the sources of raw materials. 

Eight volumes that give the sources of raw materials and products together with processes and processing data. 

The cheap source of raw materials decided our Sparte on Auschwitz," he said. "I knew nothing about the employment of inmates until a month after the site had finally been decided upon. Then an order came from Goering approving Farben s employment of the inmates."... 

Vogt, E. (1949). The birch as a source of raw material during the Stone Age. Proceedings of the Prehistoric Society 5 50-51. 

The chlorophylls are a group of naturally occurring pigments produced in all photosynthetic plants including algae and some bacteria. Hendry24 estimated annual production at about 1,100,000,000 tons with about 75% being produced in aquatic, primarily marine, environments. Obviously as a source of raw material for food colorants, chlorophylls present no problem with supply. 

In addition, with the very low value of rich C02 streams, C02 could be considered an oxygen source for chemical production, whereas biomass itself could be also a source of raw materials (see below) or would be used for energy production. 

A major part of Taguchi s philosophy centers around the separation of effects caused by noise factors and effects caused by control factors. Control factors are variables that are under the control of the experimenter flow rate, pH, concentration, reactor temperature, etc. In contrast, noise factors are variables that are not under the control of the experimenter ambient temperature, ambient humidity, identity of process operator (Joe or Jane), source of raw material, etc. Control factors are sometimes called process factors noise factors are sometimes called environmental factors. 

Figure 14.8. The inner array exists in the three-dimensional space of control factors x X2, and X3 these might represent temperature, flow rate, and pH, respectively. The outer array is represented by the small fractional factorial designs shown at each factor combination of the inner array. It is important to understand that this inner outer does not exist in the control factor space - it exists in a separate three-dimensional space of noise factors, designated for our purposes here as z Zj, and Z3 these might represent ambient humidity, source of raw material, and identity of process operator.

---