China Petrochemical News Network reported in recent years that the Public Works Operations Department of Tahe Refining and Chemical Company has adopted measures such as source governance, process control, and hierarchical control to pay close attention to environmental protection, emission reduction and pollutant prevention.
COD (chemical oxygen demand) emissions have been declining year after year.
The cumulative value is as high as 62.
58%, a record low in five years.
Source governance is effective
Petroleum shock is the main factor that makes the company's sewage treatment system difficult to operate stably.
In recent years, the Tahe Refining and Chemical Public Works Department on the one hand has conducted research on the slop oil system of the whole plant, and a number of measures have been taken to reduce the amount of slop oil in the system, stabilize the density of crude oil, and reduce the phenomenon of oil carried in electrical desalination drainage.
On the other hand, we will coordinate the sludge oil refining, accurately calculate the sludge oil storage capacity of the sewage system, ensure the stable operation of sludge oil refining, electric desalination and degreasing, and calculate the sludge oil storage capacity of the sewage system every week, and establish an early warning mechanism.
Minimize the storage capacity of slop oil in the sewage treatment plant, and ensure that the oil from the adjustment tank of the sewage treatment plant is below the index requirements.
After five years of hard work, the imported oil content of the sewage treatment plant is stable between 500-1500 mg/L, which greatly reduces the oil-carrying situation in upstream water.
Connotation tap the potential and see the real trick
The operation department takes “connotation tapping potential” as the core, overall consideration of production equipment “use waste treatment and resource utilization”, fully relying on existing sewage treatment facilities, through connotation tapping potential and process improvement, promote management upgrade, improve operation quality and efficiency, and reduce Investment costs and operating expenses.
The first is to keep improving and do a good job in environmental protection risk management and control.
The operation department organizes all staff to identify environmental risks, investigate the environmental risks of upstream installations and sewage treatment plants, conduct comprehensive analysis based on the characteristics of pollutants discharged by upstream installations and their impact, and link up and down, strengthen hierarchical control, and reduce upstream water quality.
The frequency of water shocks, and the rational use of emergency adjustment tanks, improve the anti-shock level of sewage and ensure the stable operation of the sewage treatment plant.
The second is to strengthen the index control and laboratory analysis of the whole process of sewage treatment, and improve the efficiency of sewage treatment facilities.
On the basis of experimental verification, adjust the ozone concentration of the added sewage to reduce the COD (chemical oxygen demand) concentration of the discharged water, and reasonably adjust the installation height of the anaerobic tank pusher of the sewage treatment plant and the lye dosage of the biochemical tank.
Increase the concentration to improve the processing efficiency of the biochemical unit.
After continuous exploration and experimentation, the concentration of chemical oxygen demand (COD) emissions in the external drainage has stabilized at a relatively low level at this stage.
Technology upgrades see results
In recent years, Tahe Refining and Chemical Company has been focusing on "scale efficiency" and "improving quality and efficiency" to upgrade pollutant prevention and control technology, and has achieved practical results.
The first is to optimize and transform the process flow to give play to the scale benefits of sewage treatment and improve the efficiency of various sewage facilities.
The 1# sewage will be transported to the 2# sewage treatment plant through the interconnection line for treatment.
In 2020, the 1# sewage treatment plant will be shut down and zero discharge throughout the year.
The second is to improve the quality and efficiency of sewage treatment facilities.
2# Sewage plant adds ozone oxidation treatment facilities and advanced oxidation treatment facilities to improve the biodegradability of sewage and reduce the difficulty of subsequent facility treatment and the COD concentration of external drainage.
Through the improvement of quality and efficiency, the COD removal rate of sewage facilities has been increased by 30%.