Raw Material Requirements

Europe has over 40% of the 10 billion m global market for panel surfacing materials, with market share for low pressure melamine (51%), veneer (18%), paper foils (13%), high pressure laminates and paint (7% each) etc. (O Carroll, 2001). The prime substrate is particleboard and MDF, except for the uses discussed above, e.g. formwork and floating floors where plywood excels. The laminating paper is typically an absorbent kraft sheet that is saturated with resin. 

Plywood is not a homogeneous commodity product (Todd, 1982). North America manufactures predominantly softwood plywood. Asian production is tropical hardwood plywood, while European production is a mix of softwood and 

Hardwood plywood is sold in both decorative (thin boards, 6 mm) and construction (thick panels, 6mm) markets. Temperate hardwoods are used primarily for decorative purposes, although Finnish birch is an exception being used in specialized high value construction applications. Thin boards are manufactured from tropical hardwoods and are used for decorative or platform uses. Decorative uses include wall panelling and door faces. As a platform the thin board receives a decorative surface that is either printed or overlaid on the panel surface, at which point it is known as prefinished (ready to use), and these are the major items traded internationally. Thin tropical boards are manufactured with water resistant, interior grade adhesives, whereas the majority of other boards use phenolic-based resin that can be used in exterior situations. 

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Isobutyl alcohol [78-83-1] forms a substantial fraction of the butanols produced by higher alcohol synthesis over modified copper—zinc oxide-based catalysts. Conceivably, separation of this alcohol and dehydration affords an alternative route to isobutjiene [115-11 -7] for methyl /-butyl ether [1624-04-4] (MTBE) production. MTBE is a rapidly growing constituent of reformulated gasoline, but its growth is likely to be limited by available suppHes of isobutylene. Thus higher alcohol synthesis provides a process capable of supplying all of the raw materials required for manufacture of this key fuel oxygenate (24) (see Ethers). 

The main raw material required for the production of viscose is ceUulose (qv), a natural polymer of D-glucose (Fig. 1). The repeating monomer unit is a pair of anhydroglucose units (AGU). CeUulose and starch (qv) are identical but for the way in which the ring oxygen atoms alternate from side to side of the polymer chain (beta linkages) in ceUulose, but remain on the same side (alpha linkages) in starch. 

Vinyl compares favorably to other packaging materials. In 1992, a lifecycle assessment comparison of specific packages made from glass, paperboard, paper, and selected plastics concluded that vinyl was the material that has the lowest production energy and carbon dioxide emissions, as well as the lowest fossil fuel and raw material requirements of the plastics studied (169). Vinyl saves more than 34 million Btu per 1000 pounds manufactured compared to the highest energy-consuming plastic (170). 

Raw Materials. Raw material requirements vary widely, depending on use. 

Flexible batch. Both the formula and the processing instructions can change from batch to batch. Emulsion polymerization reactors are a good example of a flexible batch facility. The recipe for each produc t must detail Both the raw materials required and how conditions within the reac tor must be sequenced in order to make the desired product. 

Environmental—If a product or its raw materials require special permitting (for example, air permits) or if the client company s facility is inappropriate for the process, tolling could provide a means to achieve the company s production goal. 

The reuse or recycling of wastes can reduce the amount of freshwater and raw materials required for a process. While looking at the inputs to unit operations, think about the opportunities for reusing and recycling outputs from other operations. Note that if reused wastes are not properly documented, double-counting may occur in the material balance, particularly at the process or complete plant level that is, a waste will be quantified as an output from one process and as an input to another. 

A typical modem phosphorus fumace (12 m diameter) can produce some 4 toniKs per hour and is rated at 60-70 MW (i.e. 140000A at SOOV). Three electrodes, each weighing 60 tonnes, lead in the current. The amounts of raw material required to make 1 tonne of white phosphorus depend on their purity but are typically 8 tonnes of phosphate rock. 2 tonnes of silica, 1.5 tonnes of coke, and 0.4 tonnes of electrode carbon. The phos rfKmis vapour is driven off from the top of the fumace together with the CO and some H2 it is passed through a hot electrostatic precipitator to remove dust and then condensed by water sprays at about 70 (P4 melts at 44.T). The byproduct CO is used for supplementary heating. 

The amount of raw material required for the chemical study of luminescent substances today is much less than that required 20 or 30 years ago, due to the advance in instrumentation. In the case of a luciferin, try to obtain 1-2 mg of purified luciferin. If that is not feasible, try to obtain at least 0.1 mg of purified material, and with some luck, the structure may be obtained. 

At a minimum, the processing phase must identify the RAC to be processed and the processed fractions to be produced. Other essential information is the quantity of the RAC to be delivered to the processor and an indication of the quantity of the processed fractions to be produced. The minimum quantity of each processed fraction is driven by the requirement of the analytical laboratory and in most cases includes a substantial excess allowance. The minimum quantity of RAC to be processed may be driven by the amount of processed commodity to be produced or the minimum raw material requirements of some processes or equipment to be used. Another factor to be considered in establishing minimum amounts of both RAC and processed fractions is the amount required for a representative sample. An amount of 10 lb of strawberries may provide a representative sample of an experimental plot, whereas the same amount of pumpkins almost certainly would not. 

Colin2 came to a similar conclusion in a review of this subject area. He emphasizes that it is important to distinguish early on the difference between purification costs (e.g., equipment, solvents, packing material) and production costs (purification and cost of making the crude sample). He noted that a crude sample resulting from a multistep synthesis can itself be very expensive and will enable one to tolerate much higher purification costs. This is indeed the case in purification of synthetic oligonucleotides, where even very steep purification costs are a fraction of the costs of even the raw materials required for synthesis, let alone the total cost of synthesis. 

Material balances are the basis of process design. A material balance taken over the complete process will determine the quantities of raw materials required and products produced. Balances over individual process units set the process stream flows and compositions. 

If the additional production cannot be readily sold, the modification results in a reduction in raw material requirements, rather than increased sales, and the earnings (savings) are from the reduction in annual raw material costs. 

The stoichiometric data is included in order to perform material balances in each unit operation. The second column of the stoichiometric data shows the amount of raw material required (tons) per unit mass (tons) of the overall output, i.e. s6 + si + s8. The third column shows the ratio of each byproduct (si and. S 8 ) to product (s6) in ton/ton product. The objective function is the maximisation of product (56) output. A 20% variation in processing times was assumed. 

As with the previous example the amount of water used to process raw material is given. The ratios used for the first three units, units 1, 2 and 3, are exactly the same as in the previous example, namely, 3 kg raw material requires 1 kg of water in unit 1, 2 kg raw material requires 1 kg of water in unit 2 and 1.5 kg raw material requires 1 kg of water in unit 3. For unit 4, 2.25 kg raw material requires 1 kg of water. The time horizon of interest is 8 h. 

Constraint (8.1) is a raw material mass balance into a unit. The amount of raw material into a unit is the sum of the directly reused water, freshwater, water from storage and any other raw materials required for the specific final product. Constraint (8.1) is the form of the raw material balance where the contaminant mass in the reused water is negligible. Constraint (8.1) for the case where the contaminant mass is not negligible will be given at a later stage. It is important to note that only compatible water can be reused in product. The reuse streams each contain information on the contaminant present in the water through the state indices in the variables describing the reuse flows. 

The average processing time for the reactor to produce a batch of product is 6 hours. Mixer 1 requires 4.5 hours to produce a batch of product 1 and mixer 2 requires 5 hours to produce a batch of product 2. The reactor has a maximum capacity of 150 kg and can therefore not fulfil the raw material requirements for both mixer 1 and 2 with a single batch. The amount of water required to clean mixer... 

Table 8.1 Raw material requirements for the first illustrative example... 

Raw Material Requirements for Conventional Cobalt and Modified Rhodium Process" (103)... 

In the following, the basic principle of the flexible recipes is presented. To keep the explanations simple, we consider only one single type of end product that is produced from one single raw material on one resource at a specific location during a given period. Required are the maximum process throughput of the resource measured in tons of output per hour and the input of raw material and output of finished products, respectively. In many types of chemical mass production, raw material consumption depends on the utilization rate of the equipment employed. Hence, linear recipe functions can be derived, which indicate the input of raw material required to produce the desired amount of output. 

Manufacturing formulae should clearly indicate the product name, potency or strength, and exact batch size. It lists each of the starting raw materials required, and the quantity in which each is required. The processing instructions should contain step-by-step manufacturing instructions. The detail given should be sufficient to allow a technically competent person, unfamiliar with the process, to successfully undertake the manufacturing procedure. 

Determination of total fluoride in soil, sediments, oxides and other raw materials requires complete decomposition of the sample. Accumulation of fluoride in soil can be studied by employing appropriate extraction procedures. 

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