Ultrasonic Treatment Of Printing And Dyeing Sludge Has A Unique Role.

< p > > a href= "http://www.91se91.com/news/index_c.asp" > ultrasonic wave < /a > treatment will induce holes, holes can dissolve cell walls and release intracellular substances into the liquid phase.

Therefore, the acoustic processing parameters affecting hole formation will affect the digestion of sludge.

The increase of VS in anaerobic digestion process can be directly changed to the increase of methane production.

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< p > many people have studied the effect of sonic density, intensity and treatment time on < a href= "http://www.91se91.com/news/" > sludge > /a > crushing and digestibility enhancement.

Foreign experts are studying the effect of ultrasonic treatment on anaerobic digestion of sludge in continuous digestion reactor. It is found that the biogas production rate of sludge treated by ultrasonic treatment is higher under shorter HRT conditions.

Under the 2.5 day residence time, the digestion efficiency increased to 60% and the gas conversion efficiency increased to 40%.

The digestion rate of activated sludge and the hydrolysis rate of polymer all follow the first order kinetics, and the rate constants are 0.16/ days and 1.2/ days respectively.

Compared with the single-phase anaerobic digestion system, the efficiency of conversion of activated sludge into methane gas in two-phase anaerobic digestion is more efficient.

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< p > foreign expert Tiehm studied the effect of ultrasonic treatment on < a href= "http://www.91se91.com > anaerobic digestion sludge < /a > using different HRT (22 days, 26 days, 12 days and 8 days) batch experiments.

After pretreatment, the percentage reduction of VS in anaerobic digestion was much higher than that without pretreatment, which was 50.3% and 45.8% respectively.

The concentration of VS in effluent is about 10% lower than that in traditional anaerobic digestion.

It has been found that after ultrasonic treatment, sludge can increase its VS reduction and biogas production in anaerobic digestion.

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< p > ultrasonic treatment can improve the degradability of sludge and shorten the residence time.

Nels and other studies found that residence time could be shortened from 16 days to 4 days.

Compared with the reference group, the VS degradation rate increased by 30% during the 4 day residence time.

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< p > Tiehm analyzed the effect of treatment time and ultrasonic frequency, and pointed out that with the increase of the two pretreatment, the VS reduction of digested sludge also increased.

For example, the VS reduction of the blank group was 21.5%, while that of the 30 minute ultrasonic treatment increased to 27.3%, which was 27% higher than that of the blank group.

With the prolongation of the treatment time, the gas production and methane content in the gas increased simultaneously.

Increasing the acoustic frequency will reduce the degree of comminution and reduce the degradability of VS.

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< p > experts have studied the influence of unit input power on gas production.

With the increase of unit input power, the production of biogas also increases.

However, for the higher input power conditions (7000 and 15000 kJ/kg TS), the gas production of the two is almost the same.

For untreated sludge, 97% of biogas production came from particulate matter, while in the < a href= "http://www.91se91.com" > ultrasonic treatment sludge < /a > this ratio was only 60%.

The increase of biogas is due to the dissolution of solid particles in the sludge under the action of ultrasound, which is more convenient for the use of bacteria.

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< p > experts from European and American countries have studied ultrasonic treatment for hydrolysis.

Acidification and methanation and their relationship.

Ultrasonic treatment has little to do with acidification reaction rate, but it can provide a buffer for acidification reaction.

The hydrolysis rates of sludge treated with different acoustic densities increased by 19~75% respectively.

Therefore, the promotion effect of ultrasonic treatment on hydrolytic acidification is mainly manifested in its promotion of hydrolysis of complex organic matters.

This stimulative effect can increase the bioavailability of methanogens in the digestion process, thereby reducing the limitation of methanation at the initial stage of the reaction.

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