Wastewater includes water that has been adversely affected in quality after being used in households or industrial plants, and precipitation and snowmelt water running off from hardscapes and agricultural land, which contains various impurities.
The degree of wastewater pollution is measured through special indices which include, for instance, Chemical Oxygen Demand (COD) and volume concentrations of total suspended solids, or nitrogen and phosphorus compounds. Analysis of such indices determines the most appropriate means of treating the wastewater, with the main objective to protect the natural environment, and in particular the cleanliness of surface water.
Wastewater management at PKN ORLEN is conducted in accordance with the Polish law based on internal procedures, instructions and in-house standards.The quality and quantity of wastewater are monitored on an ongoing basis to ensure they are within the limits set in the relevant water permit.
Effluents discharge from the Płock Production Plant
|Effluents discharged to the Wisła River [m3]||14,033,032||13,506,145||- 3.8|
|COD load in effluents discharged to the Wisła River [kg per annum]1)||868,645||777,954||- 10.5|
|Suspension in effluents discharged to the Wisła River [kg per annum]||110,861||128,308||15.7|
1) Gross load
PKN ORLEN operates a highly-efficient Central Wastewater Treatment Plant (CWTP), which treats wastewater from offices and social facilities, industrial wastewater and rainfall runoff from the area of the Płock Production Plant, including that coming from third-party companies operating within its premises. All wastewater funnelled to the CWTP is subject to a multi-step treatment process which includes mechanical, physical, chemical and biological treatments. Treated wastewater, meeting the criteria specified in the Company’s water permit, is discharged into the receiving body of water. The quality of effluents that may be discharged from any specific installation is precisely defined in a quality/quantity standard, which is updated annually. At PKN ORLEN, some treated wastewater is reused to produce water suitable for various uses on the Plant’s premises (other than for human consumption) or for fire-fighting purposes, which considerably reduces the quantity of water abstracted from the Wisła river and pollutant loads discharged into the Wisła river with effluents.
Abstraction of water and discharge of treated wastewater to the Wisła river in relation to crude oil processed
In 2014, the volume of treated wastewater discharged to the Wisła river decreased by 3.8% year on year as a result of lower volumes of wastewater directed to the CWTP and an 11.7% increase in wastewater returned to produce utility water and water for fire-fighting purposes. The 10.5% decrease in the COD load discharged into the Wisła river in 2014 was attributable to a 3.8% lower volume of effluents carried to the river compared with 2013. The 47% lower phenol load in treated wastewater followed from a reduced inflow into the CWTP, which in turn was caused by maintenance shutdowns of the petrochemical units, as well as a year-on-year decrease in the volume of effluents discharged to the Wisła river.
During the effective term of its water permit, since 2012 PKN ORLEN has measured the quality of water flowing in the Wisła river 300 m above and 1,000 m below its treated effluents discharge point. The measurements are taken at least once every six months during periods of above-zero air temperatures, and cover pH, total nitrogen, total phosphorus, phenol index and mineral oil index.
The measurements have shown that in practically no cases did the theoretical increase in pollutant concentrations exceed the level of measurement accuracy. This leads to a conclusion that the reported increases in the Wisła river’s water contamination levels could not have been caused by treated effluents discharged by PKN ORLEN. Based on the findings of the above studies and results of calculations it was concluded that the actual scope of the Płock Production Plant’s impact on the Wisła river waters is only local, and is hardly noticeable about 1 km from the treated effluents discharge point.
Location of measurement points checking the quality of water receiving wastewater discharges
In 2014, at the Płock Production Plant there were no accidental releases of hazardous substances to land.
At the PTA Plant in Włocławek, all wastewater associated with the production of terephthalic acid is discharged into the individual sewage systems of ANWIL S.A.
Volume and quality of effluents discharged by the Włocławek PTA Plant
|Parameter||Year||Increase/ decrease [%]|
|Effluents discharged to ANWIL S.A.’s sewage system [m3]||1,844,880||1,817,516||-1|
|COD load in effluents discharged to ANWIL S.A.’s sewage system [kg per annum]||5,803,158||6,157,565||6|
|5-day BOD load in effluents discharged to ANWIL S.A.’s sewage system [kg per annum]||4,401,009||2,838,520||-36|
|Cobalt content in effluents discharged to ANWIL S.A.’s sewage system [kg per annum]||641||649||1|
Pollutant loads in effluents discharged by the PTA Plant to ANWIL’s sewage system
The lower 5-day BOD load in wastewater in 2014 compared with 2013 is attributable to a significant decrease in 5-day BOD load in wastewater after the metal recovery process (down 36%), which was mainly due to more efficient operation of the filter after completion of repair and maintenance work.
Volume of the ORLEN Group’s effluents discharged to the environment
|Wastewater type||Effluents discharged to the environment [m3]|
The data for 2013 and 2014 account for 36 Group companies, including PKN ORLEN S.A.
The difference between the size of the impact in 2012 and 2013 is attributable to inclusion of new data, i.e. adding Energomedia Sp. z o.o. and Spolana a.s. to 34 Group companies.