How is the sewage of the concrete batching plant produced?
The waste water of the concrete batching plant mainly includes waste water from sand and gravel separation, waste water from cleaning production and transportation equipment, site flushing water and part of rainwater.
In order to avoid the impact of concrete wastewater, the mixing plant usually does the following:
After the mixer completes the task, or before the production of other different types of concrete, it must be rinsed with water to avoid the residual concrete in the mixer, which will cause pollution to the next batch of concrete and change its performance.
Concrete engineering vehicles and transport vehicles must also rinse the mixing drum with clean water after completing the conveying task to prevent the residual concrete from hardening and agglomerating, making cleaning more difficult. The residual concrete may also cause adverse performance effects on the concrete of the next truck.
The sand and gravel conveyor belt should adopt a closed system. There are no corresponding measures for the sand and gravel conveyor belts in many mixing plants, resulting in the falling of some sand and gravel dust and soil during the conveying process, causing pollution of the production space. Washing these dust will also produce certain waste water.
The chassis and tires of the concrete truck should be cleaned by the car washing machine to ensure the clean and tidy traffic roads.
The sediment after washing the waste water in the concrete batching plant is waste residue. Most concrete companies will carry out waste residue transportation, but this not only pollutes the environment, but also wastes resources.
Therefore, the effective treatment of the remaining concrete waste water and slag can save costs and recycle.
Sewage recycling looks good for business in the long run
According to the statistics of the use of many mixing stations, if the annual output of a mixing station can reach about 100,000 cubic meters, then conservatively estimated, the cost of the equipment can be recovered in one and a half years.
Filter press can effectively treat sewage
The sewage discharged from the mixing station after cleaning the tank truck has the characteristics of high concentration, short solidification period, and difficulty in cleaning, which is a persistent problem that plagues various mixing stations.
For this kind of high-strength concrete, the water glue is relatively small, and the density of the hardened concrete is much higher than that of the low-medium-strength concrete.
The early strength of concrete is mainly provided by active minerals in cement and cementitious materials. The addition of waste water will reduce the content of fine powder with relatively high activity in concrete, so the early strength will be lowed.
However, in the later stage, the strength gradually develops, and the low-activity powder in the waste water gradually fills the voids of the concrete, thereby improving the compactness of the concrete and increasing the strength in the later stage.
In actual recycling, concrete batching plants need to be equipped with waste water and waste slurry filter presses.
The wastewater is treated by a filter press, and most of the solids will be pressed out by the filter press. The wastewater contains fewer solids. After treatment, it is recycled as production or washing water, while the filtered solids are treated in a harmless manner. Afterwards, it can also be recycled.
