Cement plant wastewater treatmentDate: 2019-06-18 Views:
With the increasingly strict national environmental protection policies, environmental protection departments at all levels are increasingly demanding wastewater discharge from the cement industry. In many local environmental impact assessments, wastewater is required to achieve zero emissions. Therefore, the construction and upgrading of cement plant wastewater treatment facilities is imperative.
The wastewater from cement plants is mainly divided into domestic and auxiliary production workshop wastewater and production wastewater according to the source.
2. Living and auxiliary production workshop wastewater
The wastewater in the living and auxiliary production workshops is mainly used for washing water and fecal sewage of cement factory workers. This kind of wastewater contains more organic substances, and also contains pathogenic bacteria such as microorganisms and E. coli. The BOD5 content is about 200mg/L. Usually, these wastewaters are fermented and decomposed by septic tanks, collected by sewage pipe network, and discharged to a sewage treatment station for unified treatment. However, most of the cement plants are far away from the urban sewage treatment station. Considering various factors such as cost, the small sewage treatment station is generally built at the beginning of the plant construction, and the treatment method combining biochemical method or physicochemical method and biochemical method is directly used for simple treatment. Re-discharge.
3. Production wastewater
Production wastewater mainly includes equipment maintenance and external drainage, waste heat power generation system sewage and laboratory wastewater. In addition to containing a small amount of oil and sediment, the equipment should not contain other harmful substances and has a small amount of water. It can be treated by grease traps and sedimentation tanks, directly discharged into the sewage pipe network and then recycled into the water treatment system. , do not have to discharge to the outside.
The waste water from the waste heat power generation system includes the circulating water discharged from the circulating pool, the sewage treated sewage, and the continuous sewage discharged from the boiler. The treatment difficulty is relatively large.
3.1 Circulating pool draining water.Since the circulating cooling water continuously evaporates during the cooling process, the salt concentration in the water is continuously increased, and the scale is easily formed. In order to ensure the qualified water quality, delay the time of condensation of the copper tube of the condenser, and increase the vacuum, it is necessary to continuously replenish fresh water into the pool. A long-term recycling will inevitably produce a part of the discharged wastewater.
3.2 Water treatment sewage, boiler continuous sewage and laboratory wastewater.
This part of the amount of wastewater is relatively small, after acid and alkali neutralization treatment (pH control is about 6.8 ~ 8.2), directly used as raw material vertical grinding mill water spray, humidification tower spray water or limestone crusher discharge pit dust Spray water, not recycled.