Efficient treatment and energy recovery for supercritical water oxidation of wastes

废物超临界水氧化的高效处理和能量回收

基本信息

批准号：
09450294
负责人：
GOTO Motonobu
金额：
$ 4.61万
依托单位：
Kumamoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

项目摘要

Supercritical water oxidation has been focused as an environmentally attractive technology where organic materials are oxidized to carbon dioxide, water, and N_2. We have applied the supercritical water oxidation to municipal excess sludge and alcohol distillery wastewater of molasses. The reaction was carried out in a batch reactor or a flow reactor with hydrogen peroxide as an oxidant in the temperature range of 473K-873K.The liquid phase products were colorless and odorless. The reaction products were analyzed in terms of total organic carbon (TOG), organic acids, and ammonium ion. TOG decreased with temperature and the oxidant amount. Acetic acid and ammonia were detected as major refractory intermediates in the product. When more than stoichiometric demand of oxidant was used, organic carbon in liquid phase was almost completely destroyed. Complete destruction of ammonia produced in the reaction required higher temperature than that of acetic acid. A tube-type flow reactor (1/8 inch-l.7 m) was constructed for the continuous treatment of wastes. The sludge was efficiently destructed by the flow reactor. Total organic carbon was measured as a function of reaction time. The kinetic data were analyzed by a single first order reaction model and two generalized models including refractory intermediate such as acetic acid. The rate constant in first order reaction model coincides with those reported in literature. The reaction rate constant for the decomposition of refractory intermediate in the generalized model was comparable to decomposition rate of acetic acid.

超临界水氧化作为一种对环境有吸引力的技术而受到关注，其中有机材料被氧化为二氧化碳、水和 N_2。我们将超临界水氧化应用于城市剩余污泥和糖蜜酒精蒸馏废水。反应在间歇反应器或流动反应器中，以过氧化氢为氧化剂，在473K-873K温度范围内进行。液相产物无色无味。分析反应产物的总有机碳（TOG）、有机酸和铵离子。 TOG随着温度和氧化剂量的增加而降低。乙酸和氨被检测为产品中的主要难熔中间体。当使用超过化学计量需求的氧化剂时，液相中的有机碳几乎完全被破坏。完全破坏反应中产生的氨需要比乙酸更高的温度。建造了管式流动反应器（1/8 英寸-l.7 m）用于废物的连续处理。污泥被流动反应器有效破坏。测量总有机碳作为反应时间的函数。通过单个一级反应模型和两个包括难熔中间体（例如乙酸）的广义模型来分析动力学数据。一级反应模型中的速率常数与文献报道的一致。广义模型中难熔中间体分解的反应速率常数与乙酸的分解速率相当。