Industrial WWTP LLC “Miratorg-West”
The Miratorg-LLC wastewater treatment plant (WWTP) operates with both the household and industrial (after pretreatment) wastewaters. The capacity of the facilities is 2 500 m3/day. As a result, the wastewaters are treated and disinfected to the quality required for the amenity needs.
Solution to which problem
Miratorg-West LLC industrial wastewaters originate from the technological process of semi-finished food and finished culinary production. Such kind of wastewaters has a high value of suspended solids, fats, COD and BOD. Furthermore, there are several lines with the periodical operational regime. Variable and high-polluted industrial wastewaters are unacceptable for discharging into the water bodies.
The treatment plant of Miratorg-West LLC was constructed in 2008 in parallel with the building of the factory. Due to the factory capacity increasing, the wastewater treatment plant was also modernized to ensure the quality of treatment required.
The WWTP operates full-time with the automated technological control and control of the technological equipment operation.
The process of wastewaters treatment includes the next serial steps (please find a process scheme in the gallery):
- Mechanical treatment
The industrial wastewaters are directed to the drum screens R2500 equipped with a squeezing screw, where the solid impurities (with size more than 1 mm) are washed, dewatered and disposed.
Household wastewaters from the factory are also fed through mechanical treatment unit presented by mechanized fine screen and aerated horizontal sand-grease traps ROTAMAT Ro5.
- Physicochemical treatment (for industrial wastewaters)
After the mechanical treatment step industrial wastewaters are directed to the equalization tank and then to the tubular flocculator where the reaction of coagulation with reagents is held. The separating flakes from water are going in the pressure flotation unit DaFinci® F150/20-80. The flotation sludge is collected by scrapers and goes to the mechanical dewatering. The treated industrial wastewaters fed to the equalization tank of biological treatment are mixed with household wastewaters, supernatant and flushing water after filter belts.
- Biological treatment
From the equalization tank wastewaters through feed well fed go to the aerotanks. Then the separating treated wastewaters and sewage sludge is held in the secondary vertical sedimentation tank. The settled sludge is partly pumped to the aerotank (return sludge), but excess sludge goes into the sludge densifier, the wastewaters fed to the clarified wastewater tank.
- Tertiary Treatment
After the biological treatment step, the wastewaters pumped to the tertiary treatment plant – «IBR-2500BM1». The design of the post-treatment station is based on the method of deep biological post-treatment immobilized on a synthetic load ЕРШ® with active sludge and further 2-step filtration, ensures the deep pollutant removal from the wastewaters.
Disinfection of wastewaters by UV on the nonpressure unit WEDECO. The treated and disinfected wastewaters through pipe by gravity discharged to the nature stream after the step.
- Sewage sludge treatment
Excess sludge from the secondary sedimentation tank pumps to the thickening further to the excess sludge tank and filterbelt press.
The sludge after the flotation of industrial waste waters (flotation sludge and flotopenes), fed to the flotation sludge tank with a mechanical stirrer. After this, the sludge is pumped to the dewatering on the centrifugal decanter Pieralisi.
The dewatered sludge is loaded into a truck and transported to a landfill for disposal.
The project on construction and modernization of the wastewater treatment plant had several steps:
- 2008 – the construction of a wastewater treatment plant with a capacity of 1 000 m3 per day (developed by MY PROJECT LLC).
- 2017-2018 – physicochemical step modernization. The capacity improvement to 2 500 m3 per day related to the factory extension («Marel Water Treatment B.V.»).
- 2019 – Modernization of the biological treatment plant: capacity improvement to 2 500 m3 per day (developed by “ECOSGROUP”).
The main result is an effective wastewaters treatment discharged to the water body.
The quantitative results are presented below: