Raw materials and process chemical recovery in industrial wastewater pollution control

This article illustrates the different methods employed to recover raw materials and process chemicals in various industries. Although only a few industries such as car painting, metal cutting, electroplating, textile, abattoir and pesticide formulation have been illustrated in case studies, almost all the industries can recover raw materials and process chemicals from their waste streams. The case studies show that the investments on new processes or systems used to recover raw materials and process chemicals have a short payback period and hence bring huge savings to those industries. Thus, each industry should try to recover raw material and process chemicals from waste streams.

By-product recovery in industrial wastewater pollution control

By-products from most industries become waste when they are not recovered. This article gives examples of by-product recovery from industries such as pulp and paper, dairy, pig farm and food processing.

Although the recovery of by-products will require new processes, the investments on those processes will be paid-back easily from the benefits brought by those by-products. Also, in order to have a sustainable development, by-product recover will play a significant role in all industries in the near future.

A case study on waste auditing in an ice cream factory

The management of the ice cream factory concerned in this study strongly felt the importance of undertaking a waste audit of its biggest waste generator, the ice cream plant. Ice cream wastewater constitutes as much as 74% of the total volume of wastewater discharged by the company to the central treatment plant of the Industrial Estate in which the factory is situated. Generation of ice cream wastes is attributed to the high consumptive use of water in the plant for washing and cleaning operations. As a result of waste auditing, methods were proposed to save water and to segregate the waste, and to modify the existing wastewater treatment system of the ice cream plant for better treatment efficiency.

Enzymes for food waste remediation and valorisation

Industrial food processing operations are among the largest contributors of environmental waste. The use of enzymes in food waste remediation and valorisation is the central theme of this chapter. Specifically, the chapter first discusses the sources and values of food waste in food supply chains. Different strategies for bioremediation of wastewater using enzymes are then reviewed. The last part of the chapter focuses on waste valorisation—how to turn food waste into valuable products using enzymes—including a discussion of emerging trends in this field.