Biochemical-performance evaluation of industrial waste water

Abstract

A estimation method of the biotransformation of industrial sewage, it relates to a estimation method of the biotransformation of waste water in sewage treatment. To solve the problem that the measurement error because of high-power diluting and the measure period is too long in the present measurement, the invention using the dissolve oxygen detecting instrument detect the endogenous respiration oxygen consumption and the biochemical breath oxygen consumption of industrial sewage, estimating the biotransformation of industrial sewage according to the relative oxygen consumption: when the water sample waiting for measuring ROC> 1, explaining that the base material does not poison or inhibit the action of the microorganism, the bigger the ROC value is the better the biotransformation of waste water waste is; When the water sample waiting for measuring ROC <1, explaining that base material poisons or inhibits the action of the microorganism, the smaller the ROC value is the stronger the toxicity of the waste water is, the worse the biotransformation of waste water waste is. The invention uses a method by detecting the oxygen consumption rate of microorganism, can detect the impact of different waste water thickness to the action of the microorganism, it avoids the error of high power dilution; and the method is simple, rapid, it can gain the measurement result in 30 ~ 60 min.

Description

technical field [0001] The invention relates to a method for evaluating biodegradability of wastewater in sewage treatment. Background technique [0002] At present, my country's wastewater pollution is mainly organic pollution, which determines that the vast majority of wastewater treatment must use biological treatment as the main treatment process. The biological treatment method has certain requirements on the biodegradability of wastewater. If the biodegradability of the wastewater is strong, it means that the wastewater is easy to biodegrade, and the wastewater can be directly treated with biological treatment processes; if the biodegradability of the wastewater is poor, it means that the wastewater is difficult to biodegrade. The biological treatment process is directly adopted, so determining the biodegradability of wastewater is of great significance to the selection of wastewater treatment process. [0003] The commonly used index to measure the biodegradability o...

AI Technical Summary

Problems solved by technology

If BOD is measured by dilution method 5 inhibition

[0012] (2) The concentration of organic matter directly affects the oxygen consumption rate in the biodegradation process. When the substrate concentration is very low, the oxygen consumption rate is proportional to the first power of the organic substrate concentration, but when the raw sewage substrate concentration is high, it will does not follow this rule

The concentration of nitrobenzene in the diluted water sample (based on the concentration of 1000mg / L in raw water) is 0.4mg / L, 0.6mg / L, and 1.2mg / L respectively, which are all lower than the "Comprehensive Wastewater Discharge Standard (GB8978-1996)" one The 2.0mg / L stipulated in the grade standard, it can be considered that the concentration of nitrobenzene in the water sample after high dilution has little effect on the microbial activity, and cannot represent the biochemical characteristics of the original wastewater

[0014] Therefore, for high-concentration industrial wastewater, the high-fold dilution method is used to determine BOD 5 Or use it to judge the biodegradability of sewage, it can only explain the results in the diluted state, and cannot represent the nature of the original sewage, BOD 5 The / COD index ignores the impact of pollutant concentration in wastewater on biodegradability, and the error is large in the process of use. This result shows that the biochemical characteristics of high-concentration sewage water quality are not completely correct

[0015] 2. The measurement cycle is too long:

[0016] BOD 5 It takes five days from the beginning of the measurement to the result. The measurement period is too long. In the face of complex and changeable sewage water quality, the original measurement method cannot guide the engineering practice in time, which brings changes to the operation and management of sewage treatment facilities.

[0017] High content of refractory substances in wastewater, high biological toxicity, and many inhibitory substances may be the cause of poor biochemical properties of wastewater

BOD 5 When the / COD ratio is low, it can be considered that the biodegradability of the wastewater is poor, but it cannot explain the cause of the poor biodegradability

Images