The study describes and analyses the relationship between the production of waste in animal product processing industries on the one hand and the prevention and treatment of the waste on the other. The industries discussed are slaughterhouses, tanneries and the dairy industry. The report offers a summary of the knowledge on production, prevention and treatment of waste in these three animal products processing industries. Because of the limited time available for this study, the problems that occur in the mentioned industries have not been treated in full detail. Important questions related to the subject are those regarding: (1) the differences between various product processing methods; (2) the reduction of the production of waste; and (3) the methods of waste treatment. Chapter 1 provides a general introduction to the subject, the different types of waste produced, the variables by which to measure pollution and the definition of the Key Indicator (quantity of industrially processed product) of the environmental impact of the processing of animal products. Chapters 2, 3 and 4 describe the waste production in the three main animal products processing industries and a number of methods by which waste production might be reduced. Chapter 5 describes the handling of by-products and the treatment of waste products. The conclusions and recommendations in chapter 6 summarize the technological and policy options that may help reduce waste production and the negative impact on the environment from the processing of animal products. 1.2. General environmental impact
1.2.2. Solid waste
1.2.3. Air pollution
The manufacturing of animal products for human consumption (meat and dairy products) or for other human needs (leather), leads inevitably to the production of waste. Under traditional conditions, the quantities of products processed in a certain area used to be small and by-products were better utilized. This resulted in the production of smaller quantities of waste than at present. Nature is able to cope with certain amounts of waste via a variety of natural cleaning mechanisms. However, if the concentration of waste products increases, nature’s mechanisms become overburdened and pollution problems start to occur. Usually, small-scale home processing activities produce relatively small amounts of waste and waste water. Nature can cope with these. Yet as a consequence of the increasing emphasis on large scale production (e.g. for reasons of efficiency, increase in scale of production and hygiene) considerably greater amounts of waste will be produced and steps will have to be taken to keep this production at acceptable levels. Also methods will have to be found or developed for a more efficient use of by-products and for improved treatment of waste products. Because large scale processes are not easy to survey, the checking of waste production is a problematic undertaking and special efforts are needed to find out where in the production process waste is produced. An example that illustrates the relationship between the scale of production and the production of waste is that of the production of hard cheese. Before large scale production of cheese came into existence, whey was considered as a valuable by-product that could be used as animal feed. In the Netherlands, about 50 percent of all the milk produced is used for the production of cheese. The whey which is produced in the process could lead to enormous environmental problems partly because the costs of transport of this whey to the farm for use as animal feed is a costly affair. Only after environmental considerations had become more important, efforts were made to solve this problem. Eventually this has resulted in the establishment of a production line of whey-powder which is now-a-days considered a valuable product. The example also shows that the...