Study on Extended Operation Conditions of Activated Sludge Quinone Fingerprint Analysis

Under the premise of ensuring the effect of sewage treatment, the stability of the worm reduction sludge technology mainly includes: the influence of worms on the microbial community structure of activated sludge, the environmental factors that affect the stability of the worm reduction sludge, and the optimal process parameters of the system and so on
.

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1 The influence of worms on the microbial community structure of activated sludge

The group composition of microorganisms is one of the important factors that determine the ability of biological treatment systems to degrade pollutants
.

Whether the worm reduction sludge in the sewage treatment process adversely affects the microbial community structure and ultimately affects the water treatment effect is a key factor in determining whether the worm reduction sludge is feasible

(1) Research on the extended operating conditions of activated sludge quinone fingerprint analysis.
In recent years, the commonly used microbial community structure analysis techniques at home and abroad mainly include: biomarker methods established on the basis of microbial chemical composition analysis, such as quinone fingerprint method and phospholipid fatty acid method And so on, modern molecular biology technology that takes DNA as the target, such as rRNA gene sequencing technology, genetic fingerprinting and other methods
.

Among them, the quinone fingerprint method is simple and easy to perform.

Although the quinone fingerprint method is widely used, quinone fingerprint analysis includes quinone extraction, purification and high performance liquid chromatography (HPLC) analysis.
The entire process is very time-consuming.
In addition, the activated sludge needs to be preserved when analyzing the microbial community structure of activated sludge.
Long time
.

Therefore, it is necessary to find a way to shorten the time of quinone fingerprint analysis and preserve the activated sludge without changing the microbial community structure of the activated sludge

Different types of activated sludge (from different sewage plants) and activated sludge from different operating periods of the same sewage treatment plant were taken, put in a refrigerator at -20°C for 3 weeks, and then extracted quinones for HPLC analysis
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As a result, various quinones appeared in one-to-one correspondence before and after freezing of all activated sludge, and the mole fraction of various quinones changed little

Table 9-2 Fingerprints before and after freezing of activated sludge microorganisms

Table 9-3 Microbial diversity DQ and species uniformity EQ

According to the dissimilarity index D(i,j), D(i,j)<0.

1, the two quinone fingerprints are similar; D(i,j)>0.

DQ=[sum(f _K ) ^1/2 ] ² (9-1)

EQ=DQ/ _n                       (9-2)

In the formula, f _k is the mole fraction of quinone k; n is the number of quinone species in the sample
.

D(i,j)=(1/2)2∑|f _ki -f _kj | (9-3)

f _ki and f _kj respectively represent the population; and the mole fraction of any quinone k in the population
.

The experimental temperature of high performance liquid chromatograph (HPLC) was set to several different temperatures such as 24℃, 30℃, 35℃, 40℃, etc.
, to investigate whether different temperatures have an effect on the discovery of quinones on the same activated sludge
.

The results show that all the quinones in the activated sludge will appear one by one at the above various experimental temperatures; for each quinone, the higher the temperature, the shorter the time it takes for the quinone to be detected

Related links: The influence of activated sludge itself on sludge reduction and the application bottleneck of worm reduction sludge technology