摘要
化学需氧量(COD)是评价水体污染程度的一项重要综合性指标。随着环境污染问题的日益严重,传统的测量方法由于存在分析成本高、时间长,并且还会造成二次污染等问题,已经不能够满足污水检测的需求,提出了采用光谱技术进行畜禽污水COD快速测定的方法。采用A SD公司的便携式光谱仪,选用容积分别为1000 mL和2000 mL的烧杯作为盛样容器,对18个不同COD浓度水平的污水样本进行了测量。通过吸光度与水样COD值的相关性分析表明,水样的光谱特性与COD值之间存在较好的相关性,以此建立偏最小二乘回归模型。结果表明,两种不同盛样容器(1000 mL、2000 mL)下的预测决定系数达到0.9895和0.9985,校正样本标准偏差为14.2和11.5,预测样本标准偏差为22和32,预测相对偏差均在10%以下,能够满足农业工程应用的要求。说明可以利用光谱技术对畜禽污水的COD含量进行定量分析,COD预测模型的建立也将为开发水质在线检测仪器提供技术基础。
Chemical oxygen demand（COD） is an important index in evaluating the pollution degree of the wastewater. Traditional methods cannot satisfy the demand of the wastewater detection for its high cost, long time, and second pollution. A rapid measurement method was put forward in this paper by using spectroscopy techniques. A total of 18 wastewater samples with different concentrations （1000 mL, 2000 mL） were measured using the ASD Handheld FieldSpec spectrometer. The results from both spectral absorbance and COD values in wastewater show that there are high correlation coefficients between spectral features and COD values. The partial least square regression models were therefore developed. The r^2 values between measured and predicted values of COD in wastewater with containers of 1000 mL and 2000 mL were 0. 9895 and 0. 9985, the standard errors of calibration were 14.2 and 11.5, and standard errors of prediction were 22 and 32, respectively. The relative standard deviations for unknown samples were below 10%. The tested precision can meet the requirements of the application in agriculture engineering. Compared with standard chemical method, it indicates that the spectroscopy technique can be applied in the quantitative analysis of COD in livestock wastewater, and the predictive model for COD provides a basis for developing potable instrument to detect water quality on line.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2006年第6期148-151,共4页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金项目(30270773)
高等学校优秀青年教师教学科研奖励计划(02411)
高等学校博士学科点专项科研基金资助课题(20040335034)
浙江省重大科技攻关项目(2005C12029)
浙江省科技厅重点项目(2005C21094)
关键词
光谱技术
畜禽污水
化学需氧量
偏最小二乘
spectroscopy technology
livestock wastewater
chemical oxygen demand
partial least squares
