Water minimization

So far the discussion on water minimization has restricted consideration to identify opportunities for water reuse. Maximizing water reuse minimizes both fresh water consumption and wastewater generation. However, the process constraints for inlet concentrations, outlet concentrations and flowrates have so far been fixed. Often there is freedom to change the conditions within the operation. Typical process changes that might be contemplated include ... 

As with the case for water minimization, the graphical methods used for effluent treatment and regeneration have some severe limitations. As before, multiple contaminants are difficult to handle, constraints, piping and sewer costs, multiple treatment processes and retrofit are all difficult to handle. To include all of these complications requires an approach based on the optimization of the superstructure. 

The company has now been told that it must reduce the total water demand by at least 10 per cent. Carry out a water minimization study to determine the scope for reusing water. Discussions with the operations managers have concluded that not all the operations need to be fed with freshwater. The maximum concentrations that can be tolerated at the inlet of the operations are given in Table 26.20. 

Mann JG and Liu YA, (1999), Industrial Water Reuse and Waste water Minimization, McGraw-Hill. 

Gouws, J.F., Majozi, T., Gadalla, M., 2008. Flexible mass transfer model for water minimization in batch plants. Chem. Eng. Process., 47 2323-2335... 

Gouws, J.F., Majozi, T., Gadalla, M., 2008. Flexible mass transfer model for water minimization in batch plants. Chem. Eng. Process., 47 2323-2335 Gouws, J.F., Majozi, T., 2009. Usage of inherent storage for minimisation of wastewater in multipurpose batch plants. Chem. Eng. Sci., 64 3545-3554 Majozi, T., 2005. Wastewater minimization using central reusable storage in batch plants. Comput. Chem. Eng., 29 1631-1646... 

Hallale, N., 2002. A new graphical targeting method for water minimization. Adv. Environ. Res., 6 377-390... 

The purification procedure occasionally leads to product contaminated with organotins. The submitters have found that careful washing with water minimizes this problem. The checkers found that distillation of product at a slow rate allows the unwanted tin to escape to the cold trap. 

Consumption of organic solvents avoided. Direct analysis of contaminants in water Minimal, noncontaminating waste Faster analysis real-time detection and high throughput Availability of portable biosensor systems Applicable to early-warning and on-site monitoring Nonqualified personnel required user-friendly Equipment cost-effective... 

Dry phenols and CCI4 Corrosive attack. Traces of water minimize the corrosive attack... 

Table 3.2 contains analogous information concerning the intensities of the various vibrational inodes. Comparison with the data in the last row illustrates the difficulty in computing experimental intensities to a high degree of accuracy. As in the ease of the frequencies, it appears that the DZP basis set seems to perform about as well as any of the much more extended sets in a number of instances. Deletion of the polarization functions leads to erratic fluctuations in the intensities, particularly the Vj symmetric stretching frequency of water. Minimal and 3-2IG are especially bad and should be avoided. Correlation does not influence the intensities in an obvious predictable manner. 

N. Hallale and D. M. Fraser, Capital Cost Targets for Mass Exchange Networks. A Special Case Water Minimization, Chemical Engineering Science, 53 (2), 293-313 (1998). 

Water management is another aspect that has to be kept in mind. After removal and recovery of the by-products, mostly inorganic chemicals, soluble or insoluble, it might be possible to recycle the used water, which will naturally result in water minimization and better water management. 

Aspen Split conceptual design of azeotropic systems Aspen Water minimize water usage... 

Dust in storage section Spraying with water, minimization of material employment Less material employment, less interest rates... 

Substance Partition coefficient olive oil water Minimal immobilizing concentration. mol/1 (water)... 

Wang, Y.P. and Smith, R. (1994) Waste water minimization. Chemical Engineering Science, 49 (7),... 

Classification Nonaromatic phosphorus compd. Empirical C9H21O3P Formula [(CH3)2CH]3P03 Properties Colorless liq. char, odor misc. with most common org. soivs. insol. in water m.w. 208.27 dens. 0.914 (20/4 C) b.p. 94-96 C (50 mm) flash pt. (COC) 73.9 C ref. index 1.4110 Toxicology LD50 (oral, rat) 167 mg/kg, (IP, mouse) 500 mg/kg, (skin, rabbit) > 2 g/kg poison by ing. mod. toxic by IP route irritant mutagenic data TSCA listed Precaution Combustible hydrolyzes slowly in water minimize exposure to air Hazardous Decomp. Prods. Heated to decomp., emits toxic fumes of POx Storage Moisture-sensitive Uses Intermediate for insecticides, pharmaceuticals, mfg. of phosphonate esters, acids, and salts component of vinyl stabilizers lubricant additive specialty solvent heat and light stabilizer, antioxidant, metal chelator for polyester... 

G.F. Gissel, Waste Water Minimization at the Vulcan Port Edwards Chlor-Alkali Facility, 39th Chlorine Institute Plant Operations Seminar, Washington, DC (1996). 

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