For bulk materials, the tank car can be used for loading, that is, the lime powder can be directly sent to the silo for storage by the lime powder transport vehicle through the feeding pump. In this way, the degree of automation is high, the workload of workers is small, there is no package breaking action, and the workshop environment is good. However, in this way, it is necessary to have lime powder manufacturers near the water plant. Bagged lime powder is divided into two types: 25kg package (small bags) and 500kg package (large bags). For small bags, workers put small bags of lime powder into the conveyor belt. The conveyor belt transports small bags of lime powder into the bag cutter for unpacking. After unpacking, the lime powder is pumped into the silo by the screw conveyor for storage, and the waste bags are discharged from the bag outlet through the press. This unpacking work is in a fully automatic closed state and the workshop environment is good. However, for large water plants, workers put small bags of lime powder with high frequency and labor intensity. For large bags, workers take large bags of lime powder and put them into the bag breaker at the top of the silo. The rubber seal is set in the bag breaker and tightly wrapped around the bags to avoid dust leakage. When the bag breaker breaks the bags automatically, the negative pressure dust collector works. In order to prevent dust from overflowing after discharging, a circle of baffle is set around the bag breaker. In this way, the operation intensity of workers is small and the workshop environment is good, which is suitable for the dosing of lime powder in large water plants.
The key of the two systems is that the flow of lime powder feeder can be stable and continuous. The flow of the feeder has a linear relationship with the rotational speed, and has the metering function. At the same time, the metering capacity can be adjusted through the frequency converter in the electric control cabinet. The screw of the feeder has self-cleaning function and will not be blocked under normal working conditions. After the lime powder is accurately measured by the feeder, it is transported to the dissolution tank by the screw conveyor, and the dissolved water is injected at a certain proportion at the same time, and then stirred to form a certain concentration of lime hydrate.
The delivery method can be gravity delivery or pressure delivery, mainly pressure delivery. During pressure delivery, wear-resistant and non-clogging delivery pumps, such as screw pump and diaphragm pump, shall be used. Screw pump is selected as the lime hydrate delivery pump. The flow of the pump is adjusted by frequency converter to achieve accurate and continuous feeding. Lime powder dosing is generally used for emergency treatment and can only be put into operation when necessary. The pipeline shall be flushed immediately after each work is completed to prevent lime powder deposition from blocking the pipeline and affecting the normal operation of the system. Therefore, the delivery pump can also be used as a flushing pump, which can be used for flushing the dosing pipeline when necessary. The flushing can be carried out automatically or manually.