Nitrification of high strength ammonia wastewaters: Comparative study of immobilisation media
Nitrification of high strength ammonia wastewaters: Comparative study of immobilisation media
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DOI：
10.1016/s0043-1354(00)00365-1
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发表时间：
2001-04-01
期刊：
影响因子：
12.8
通讯作者：
Young, AA
中科院分区：
文献类型：
--
作者：
Rostron, WM;Stuckey, DC;Young, AA
由于立法压力，未来英国的污泥生产和处理将大幅增加，导致上清液氨含量高（500-1000 mg l(-1)）和“硬”COD（类似于500 mg l(-1)）。需要一个小占地面积的反应器来有效硝化这种废水，这项工作的目的是在各种条件下比较多种固定介质，以确定哪种介质最有利于未来的发展。使用高浓度合成氨废水（500 mg Nl(-1)）运行含有自由悬浮和固定生物质的实验室规模连续搅拌釜反应器，以确定不同温度下的硝化速率以及氨和COD负荷。根据所采用的处理工艺，污泥液中的 COD:NH 比例变化很大，因此 1:1 和 2:1 的比例经测试是相当典型的。自由悬浮的硝化菌在 1 天的水力停留时间 (HRT) 下被从反应器中洗出，而含有吸附颗粒（Linpor 和 Kaldnes）和 PVA 封装的硝化菌的反应器继续部分硝化至 12 小时，并且添加氧气增强了硝化作用。温度从 25 摄氏度降低至 16 摄氏度仅导致固定化细胞反应器中硝化作用小幅下降（10%），这表明硝化作用是传质而不是动力学控制。由于异养种群的生长，当向饲料中添加葡萄糖（500 mg l(-1)）时，硝化作用会减少。吸附式生物质反应器损失了 35% 的硝化作用，而 PVA 仅损失了 7%，而且异养生物对 PVA 的定植似乎比 Linpor 和 Kaldnes 更困难。所有颗粒的呼吸速率随着反应器中石灰的加入而增加，固定在 PVA 中的硝化细菌在固定后保留了大约 40% 的活力。 PVA 反应器的体积硝化率通常高于 Linpor 和 Kaldnes，并且为： 悬浮生物质反应器：0.36；林波尔：0.57； Kaldnes：0.53 和 PVA：0.70 kg N m(-3)-反应器 d(-1)，反应器填充率为 25%。对于 Linpor、Kaldnes 和 PVA，这些分别相当于 2.28、4.24 和 3.97 g Nm(-2)-media d(-1)；因此，卡尔德内斯的其他反应堆的反应速率值得进一步调查。然而，在所有条件下具有最高硝化率的 PVA 颗粒显示出作为固定介质的前景，并且可以进一步优化高浓度氨废水的硝化。 (C) 2001 Elsevier Science Ltd. 保留所有权利。
Due to legislative pressures, sludge production and processing in the UK will increase substantially in the future resulting in a supernatant liquid high in ammonia (500-1000 mg l(-1)) and "hard" COD (similar to 500 mg l(-1)). A small footprint reactor is required to effectively nitrify this effluent, and the aim of this work was to compare a number of immobilisation media under a variety of conditions in order to determine which media held the most promise for future development. Laboratory-scale continuously stirred tank reactors containing freely suspended and immobilised biomass were operated with a high-strength synthetic ammonia wastewater (500 mg Nl(-1)) to determine the nitrification rates at various temperatures, and ammonia and COD loadings. COD:NH, ratios in sludge liquors vary widely depending on the treatment processes employed, and therefore ratios of 1:1 and 2:1 were tested as being fairly typical. The freely suspended nitrifiers were washed out of the reactors at a 1 d hydraulic retention time (HRT), whereas the reactors containing adsorption particles (Linpor and Kaldnes) and PVA-encapsulated nitrifiers continued partially nitrifying down to 12 h, and oxygen addition enhanced nitrification. A decrease in temperature from 25 to 16 degreesC only caused a small (10%) decrease in nitrification in the immobilised cell reactors, demonstrating that nitrification was mass transfer rather than kinetically controlled. A reduction in nitrification occurred when glucose (500 mg l(-1)) was added to the feed due to the growth of a heterotrophic population. The adsorbed biomass reactors lost 35% of nitrification compared to only 7% with PVA, and it appears that the colonisation of PVA by heterotrophs is more difficult than for Linpor and Kaldnes. Respiration rates for all particles increased with lime in the reactors, and nitrifiers immobilised in PVA retained approximately 40% of their viability after immobilisation. Volumetric nitrification rates were generally higher for the PVA reactor than for Linpor and Kaldnes, and were: suspended biomass reactor: 0.36; Linpor: 0.57; Kaldnes: 0.53 and PVA: 0.70 kg N m(-3)-reactor d(-1) for a 25% reactor fill. These equate to 2.28, 4.24 and 3.97 g Nm(-2)-media d(-1) for Linpor, Kaldnes and PVA respectively; hence other reactor till rates for Kaldnes warrant further investigation. However, the PVA particles with the highest nitrification rates under all conditions showed promise as an immobilisation medium, and are amenable to further optimisation for the nitrification of high-strength ammonia wastewaters. (C) 2001 Elsevier Science Ltd. All rights reserved.