Waste factor analysis

A comparative cost analysis showed that the classical resolution route (Scheme 8.2) was 12 times cheaper than the discovery route (Scheme 8.1). The classical resolution route was successfully scaled up and used to launch the product and provide the first year s market supply. However, using a final-stage resolution meant that by definition half of the synthetic materials were thrown away. When an E factor analysis [8] was performed on the pregabalin synthesis it was found that 86 kg of waste was being produced for every kilogram of the desired product, and this inspired a search for more efficient chemistries. 

In a sold-out market, a DuPont intermediates process was operating at 56% of peak capacity. The major cause of the rate limitation was identified as poor decanter operation. The decanter recovered a valuable catalyst, and the poor operation was caused by fouling from catalyst solids. Returning the process to high utility required a 20-day shutdown. During the shutdown, the vessel was pumped out and cleaned by water washing. The solids and hydrolyzed catalyst were then drummed and incinerated. A waste stream analysis identified three cost factors the volume of wastewater that had to be treated, the cost of the lost catalyst, and the incineration cost. 

ICP-MS is very promising in the area of environmental studies. Many elements can be determined directly in drinking water. In waste water analysis sample decomposition by treatment with HNO3-H2O2 is often required and the most frequent isobaric interferences have been described [559]. For seawater analysis, the salt contents makes sample pretreatment necessary, which can be done by chelate extraction. Beauchemin et al. [560] obtained a preconcentration of a factor of 50 by sorption of the trace elements onto an SiC>2 column treated with 8-hydroxyquino-line and determined Ni, Cu, Zn, Mo, Cd, Pb and U in seawater. In river water Na, Mg, K, Ca, Al, V, Cr, Mn, Cu, Zn, Sr, Mo, Sb, Ba and U could be determined directly and Co, Ni, Cd and Pb after the above mentioned preconcentration procedure. For As, preconcentration by evaporation of the sample was sufficient. Isotope dilution delivers the highest accuracy [561] and the procedure has been applied to... 

Generally, the recognized ore zones are primarily phosphorites whereas strata in the waste zones include more dolostones and silicic layers. Factor analysis to determine the relationships of the lithology and the COs content in CFA considered four variables (1) the degree of COs substitution for P04 in CFA, (2) CFA content, (3) silicate mineral content (quartz + sheet silicates + feldspars), and (4) carbonate mineral content (dolomite + calcite). Because the more-, and less-weathered strata have lost much of their original carbonate mineral content, only the least-weathered samples are used for factor analysis, as they are the best proxy for the unweathered Phosphoria Formation. 

De Paola M G, Ricca E, Calabrb V, Curdo S, lorio G (2009), Factor analysis of transesterification reaction of waste oil for biodiesel production . Bioresource Technol, 100(21), 5126-5131. 

Oxygen corrosion involves many accelerating factors such as the concentration of aggressive anions beneath deposits, intermittent operation, and variable water chemistry. How each factor contributes to attack is often difficult to assess by visual inspection alone. Chemical analysis of corrosion products and deposits is often beneficial, as is more detailed microscopic examination of corrosion products and wasted regions. 

In examining the technical options for plastic waste management, chemical recycling appears to be the least developed and most difficult. In this paper, BP Chemicals sets out its analysis of the factors that will determine the choice of chemical recycling process technology. From this a process concept based on thermal cracking is developed and the hurdles to be overcome before such a process can be realised is discussed. 

From this further analysis, the actual amount of waste (and its nature) per kilogram of product will become evident. At this stage it is also important to look forward and assess options for recycling or reusing the waste on site for example if a solvent can be efficiently recovered then this should be taken into account in calculating the E-factor. Although the choice of which route to fully optimize may not be obvious even from this further analysis, it will facilitate a reasoned discussion of the issues. 

Factors that may be considered in selecting a tier include the physical characteristics of the facility and surrounding terrain, the anticipated waste compositions and feed rates, and the level of resources available for conducting the analysis. The main distinction between the tiers is the focal... 

An example of the effects of waste settlement can be illustrated by a recent incident at a hazardous waste landfill facility in California.5 At this facility, waste settlement led to sliding of the waste, causing the standpipes (used to monitor secondary leachate collection sumps) to move 60-90 ft downslope in 1 day. Because there was a very low coefficient of friction between the primary liner and the geonet, the waste (which was deposited in a canyon) slid down the canyon. There was also a failure zone between the secondary liner and the clay. A two-dimensional slope stability analysis at the site indicated a factor of safety (FS) greater than 1. A three-dimensional slope stability analysis, however, showed that the safety factor had dropped below one. Three-dimensional slope stability analyses should therefore be considered with canyon and trench landfills. 

The separation factor, r, in an isotope separation process is the ratio of the relative concentration of desired isotope in the product, p, to its relative concentration in the feed, f. Denoting the feed to the i th stage, the i th section of an overall plant, or the ith overall plant, as mol/s of isotope with an isotope fraction Zj, yielding product at a rate of Yj mol/s of analysis yi, and waste at a rate of Xj mol/s and isotope analysis Xj, we have for a two isotope feed... 

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