Use of Cement Kilns in Managing Solid and Hazardous Wastes: Implementation in Australia

The use of cement kilns for managing solid and hazardous wastes is facilitated by the high temperature, long gas retention periods, natural alkaline environment, minimum amount of waste produced and high thermal capacity. The main benefits include energy recovery, conservation of fossil fuels, reduction in cement production costs and the use of already existing facilities.
The test burns conducted in cement kilns worldwide have demonstrated very high destruction efficiencies for most stable organic compounds, with toxic contaminants barely above the background levels.
There are several cement plants in the US and Europe presently using solid and hazardous wastes as supplementary fuel. The application of this technology in Australia has been ignored in the past. An international conference (Kilnburn'92) on the role of cement kilns in waste management was held recently in Australia and has enhanced the implementation of this technology in Australia.     

EARTH-BANKED TANKS FOR THE WINTER STORAGE OF ANIMAL SLURRY

Inadequate animal slurry storage has become an important issue in the agricultural sector in Ireland, and the lack of adequate conventional storage capacity has resulted in the spreading of slurry on land at inappropriate times of the year. This can lead to inefficient nutrient recycling and possible enrichment of adjacent surface and groundwaters. However, the largest contributor from agriculture to this enrichment is considered to be from farmyard leakage, rather than overland flow. The objective of this study was to examine the feasibility of using earth-banked tanks as an alternative and economical means of winter storage for animal and other farmyard wastes. The paper describes an investigation into the use of such a tank at one location. Slurry infiltration rates, groundwater-level changes and groundwater-quality measurements at the tank site are reported. The study demonstrates that, if properly constructed using adequately compacted and suitable soil, earth-banked tanks can be successfully used to temporarily, store highly-polluting liquids such as animal slurries.