Mendez J M, Jimenez B, Maya C
Orizaba Institute of Technology (ITO), 852 Tecnológico, Zapata 94320, Orizaba, Mexico.
Water Sci Technol. 2004;50(9):67-74.
Ammonia is a disinfectant which can diffuse through the membrane of highly resistant structures like helminth ova. Thus, it can be considered an alternative disinfectant of wastewater sludge with high pathogenic content. In this study, the kinetic parameters of the Hom model were used to describe the inactivation with ammonia of faecal coliforms, Salmonella spp. and viable helminth ova. These were obtained in processes considering the addition of ammonia alone as well as for ammonia combined with an increase in temperature. The sludge was sampled from a municipal wastewater treatment plant using an APT (Advanced Primary Treatment) or CEP (Chemical Enhanced Primary) process. With 20% w/w of ammonia, 7 logs of faecal coliforms, 6 logs of Salmonella spp., and 83% of viable helminth ova were reduced in 2 hours contact time. To eliminate 100% of the helminth ova from samples having 88-132 ova/g TS it was needed to combine 20% of ammonia with 50 degrees C. The analysis of parameters k, n and m indicate higher resistance to inactivation of helminth ova compared to bacteria and a better performance of the ammonia process than lime stabilization to inactivate microorganisms. In addition, ammonia increased the agricultural value of the biosolids produced.
氨是一种消毒剂，它可以扩散穿过诸如蠕虫卵等具有高度抗性结构的膜。因此，它可被视为具有高致病含量的废水污泥的替代消毒剂。在本研究中，使用霍姆模型的动力学参数来描述氨对粪大肠菌群、沙门氏菌属和活蠕虫卵的灭活情况。这些参数是在仅添加氨以及氨与温度升高相结合的过程中获得的。污泥取自采用先进一级处理（APT）或化学强化一级处理（CEP）工艺的城市污水处理厂。在2小时的接触时间内，添加20%（重量/重量）的氨可使7个对数级的粪大肠菌群、6个对数级的沙门氏菌属和83%的活蠕虫卵减少。要从每克总固体含有88 - 132个虫卵的样品中消除100%的蠕虫卵，需要将20%的氨与50摄氏度相结合。对参数k、n和m的分析表明，与细菌相比，蠕虫卵对灭活的抗性更高，并且氨处理在灭活微生物方面比石灰稳定化表现更好。此外，氨提高了所产生生物固体的农业价值。
