1. Decanter centrifuge is suitable for all kinds of sludge; belt machine is also suitable for all kinds of sludge, but for oily, viscous, remaining activated sludge, it needs a large amount of medicine and dehydration is difficult.
2. The problem of feed control
The Decanter centrifuge can automatically adjust the slip and torque according to the change of the feed concentration, and the belt machine must be manually adjusted.
3. Problems of solid recovery rate and dosage
The solid recovery rate of the Decanter centrifuge is indeed higher than that of the belt machine, but this does not mean that the solid recovery rate of the belt machine cannot be used if it is low. In fact, the belt filter must be returned to the front and reprocessed.
The dosage of medicament is added. A 15 × 104t / d urban sewage treatment plant designed by the author adopts a decanter centrifuge for dehydration. The measured consumption of PAM per ton of dry sludge after production is 1.7-2.0kg. The lower the consumption of medicine with machine (PAM) is generally 4kg / (t [dry mud]).
4. Power consumption problem
The difference in power consumption is not as claimed by the manufacturer of the machine. It is actually controversial. The centrifuge manufacturers will also say that their centrifuges use less electricity. The author speaks a jargon here: power consumption differs mainly depending on the model and the amount of processing capacity.
The noise of the centrifuge is large, but the noise with the machine is not the machine itself, mainly the sound of washing water, the sound feels better than the centrifuge;
5. The life of the machine
The bearing life of a good-quality belt machine is theoretically 20a, which is similar to the life of the host machine. The filter belt needs to be replaced frequently. The filter belt is generally replaced continuously for 2000h operation. If it is intermittently operated and maintained well, then it depends on the length of use and shutdown In contrast, regardless of whether it is a domestic or imported belt machine, the filter belt can generally be replaced with a domestic filter belt, so the cost of replacing the filter belt is not high, and the current domestic equipment of the decanter centrifuge is reliable, stable, and easy to maintain and maintain.
In theory, the running time of the belt machine can also run for 24 hours. Of course, the continuous operation of the belt machine is not as reliable as the centrifuge.
6. Calculation of operating expenses
When the belt filter press dehydration machine manufacturer calculates the dehydration and centrifuge core operating costs, there are many problems in the calculation method used. The operating costs mainly include: pharmaceutical fees, electricity costs and water costs. In addition to the belt machine, there are downtime costs and flushing costs. The author took an 8 × 104t / d sewage treatment plant as an example to calculate the actual operating cost of sludge treatment. Therefore, from the perspective of operating costs, the use of centrifuges and Not higher than with the machine.