Research on improvement of the sludge odor by using HAS soil stabilizer and mechanism

The instability of the sludge will cause odor and other environmental pollution in the process of disposal and reuse. HAS soil stabilizer, Lime and Portland cement are used in this paper to modify the sewage. The experimental results showed that added by a certain content of the HAS Soil Stabilizer in sludge would be a good modification effect on removing Ammonia and Hydrogen Sulfide. When the curing time was 14d and the content was 15%, the concentration of Ammonia was 5μg/L and the removal rate could reach 93.5%. When the curing time was 3d and the content was 10% or more, the concentration of Hydrogen Sulfide can be reduced to below 0.06μg/L and the removal rate could reach 95%, conforming to the relative standards. The SEM photos of 15% HAS modified sludge showed that Ettringite and Calcium Silicate hydrate crystals were the mainly hydration products, they formed a kind of three-dimensional crystal network and completely changed the original sludge structure, which effectively prevented the organic matter to further decay, made the sludge stabilized and achieved the improvement of sludge odor.