Dewatered Sludge Treatment
Process Dewatered Sludge Treatment
Dewatered sludge treatment systems must be flexible to meet the changing requirements in the waste management industry. Dewatered sludge treated in seepex systems is more adaptable because of its consistency, dry solids content, and shear resistance.
For agricultural use, dewatered sludge is normally treated with quick lime. Because of the exothermal reaction of quick lime with water, moisture content is reduced and the sludge structure improved. The nutrient enrichment of the sludge with the addition of quick lime makes dewatered sludge more acceptable for agricultural applications. Adding quick lime results in a sterile, neutralized sludge. Minimally, the pH-value should reach at least 12.5 and the sludge temperature should be 55°C within 2 hours.
In some countries dewatered sludge storage requires a considerable reduction of organic and harmful substances. In Germany starting 2005, it is no longer allowed to store waste containing more than 5% volatile organic compounds. Use of sewage sludge in agricultural applications is limited, therefore, the current storage must be replaced by thermal treatment of sewage sludge.
Among the various thermal treatment methods, the sludge dewatering is an alternative to the incineration of the sludge in waste combustors and power stations. The sludge can be used in the construction materials industry or in the production of substitute fuel materials.
The thermal treatment is increasingly being connected with the energy technology. WASTE TO ENERGY – where the energy content of the sewage sludge is thermally used. Sludge dewatering and sludge incineration are becoming progressively more important for the sludge applications pumped through seepex systems.
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