Refuse high moisture

Simulated Japanese refuse A - High Moisture B - Intermediate moisture C - Standard moisture D - Low Moisture... 

The process flow of the pilot plant is shown in Figure 5, together with a material balance for the case of high moisture refuse. A typical energy balance is shown in Figure 6. 

Figure 6. Energy balance of the pilot plant (high moisture refuse)...

The absorption of water by refuse will be affected by particle size and density and is a function of the waste composition and landfill operating procedures. Using waste with a high moisture content, Rees and Grainger (1982) showed that increasing the waste density from 0.2 to 0.47 tonnes/m decreased gas production this was ascribed to stimulation of acid production. In similar studies with drier waste, Rees and Grainger (1982) showed that increasing the waste... 

In assessing the combustion of solid wastes in incinerators it is of interest to compare the heating value and other properties of refuse with those of other fuels. Such a comparison is presented in Table 8.12, where it is seen that compared to coal, refuse is a low-density, low-calorific value fuel, which also has a rather high moisture and ash content. However, refuse appears to have a respectable heating value compared with peat or wood. 

It is to be noted here that the calorific value of 2800 kcal/kg is typical for refuse in the U.S. Refuse in Western Europe has a calorific value of about 2000 kcal/kg [98] and the net heating value of refuse in Hong Kong is only about 1000-1200 kcal/kg because of its very high moisture content. 

Direct combustion is one way to extract the energy contained in household refuse, but its moisture content tends to be high at 20% or... 

Anaerobic microbes in the presence of water in the landfill will consume these natural products and produce methane, CO2 and humus. One study reported the average composition of 20 year old refuse to be 33 % paper, 22% ash and 12% wood [18]. Thirty core samples revealed a wide range of degradation and microbial activity that were directly attributed to sample moisture content. Recovered polyethylene degradation was evaluated and determined to be as high as 54 %. 

While there will be excursions below and above this range, the moisture content normally varies from a low average of 22 percent to a high average of 32 percent. The average among six facilities was 27 percent. European refuse has been rapidly approaching the composition of American waste as Europe has continued to "modernize its way of life. 

The natural moisture content of coarse coal refuse has been found to range from 3% to as high as 24%, but is usually less than 10% ... 

Over the last years food wastes have earned an increasing attention as feedstock for hydrogen production they include kitchen refuse, municipal wastes (a part of), food industry co-products (oil mill, cheese whey) and starch manufacturing wastes. Food wastes show high energy content (85—95% of volatile solids and 75—85% moisture) and high biodegradability, which favours microbial anaerobic development. 

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