General factors relating to waste generation in the chemical industry

13 General factors relating to waste generation in the chemical industry 

The batch process reactor system adds more flexibility but is probably the biggest contributor to waste generation. A detailed breakdown of the unit operations will give clear indications to the areas of manipulation which give most impact on waste minimisation. A step by step breakdown, as used in a Hazard and Operability (HAZOP) study, is applicable to optimising batch processes with respect to waste minimisation. 

Product isolation techniques are governed by the physical properties of the component parts of the reaction mixture and often, if processes are designed backwards from the isolation stage, as opposed to matching isolation techniques to process chemistries, more optimum material management is possible. Choice of solvent is the most obvious consideration in this respect, particularly if recyclability is a factor. 

Regulatory issues do have significant impact on the operation of industrial scale processes and must be considered in the early part of process design. These factors are more fully explored in other chapters and will not be discussed in detail here. 

Any waste minimisation project will cost money to implement. As discussed earlier, this money has to come eventually from sales of product. If company profits are to be maintained or increased then the cost of the waste minimisation project must be justified against this criterion from the outset. It is therefore useful at this point to consider the costs and benefits of waste minimisation to provide a framework for cost/benefit calculations. It is vital to carry out this exercise for any project designed to 

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