Case Study: The Practice of operating the EKOTON Catenary Screen at Wastewater Treatment Plants (Budapest, Hungary)

It is no secret that the industry market leader is the most prestigious customer for any supplier of specialized equipment in any given country. In Hungary such customer is certainly the Budapest Waterworks, FCSM Zrt., who provides wastewater treatment in Budapest. Moreover, we feel especially proud of those projects implemented in this city as they received positive professional assessment from the specialists of FCSM Zrt.

One of such projects is the project of manufacturing and installation of a unique Ekoton catenary screen for rough wastewater treatment at Angyalföld pumping station that became a substitute to an older coarse screen. In the channel, 6 mtr deep and 3 mtr wide, with the existing transporting conveyor for the wastes from the screen, a new screen had to be installed as soon as possible. Our designers had to focus on the installation and commissioning procedure of the finished product, which was to be delivered from the Ekoton plant in Poland.

We can rightfully consider this project as a special operation – due to its non-standard dimensions (3.2 mtr wide, 9 mtr long, weight 2,890 kg), the screen required the use of an escort vehicle; its installation into the channel required high-precision work by the Hungarian team of crane operators and installers. Under the guidance of an EKOTON commissioning expert, this operation was performed with surgical precision. Almost 3 hours after the channel had been closed, a penstock was reopened, and the KR 2853 catenary screen was put into operation. The flow rate supplied for this screen ranges from average values of 5-6 thous. m3/hour to 12 thous. m3/hour.

The screen was put into operation in the middle of June of 2020 and during the past six months the operation has clearly demonstrated its efficiency and reliability. The article, published by Waterworks in a professional publication in October 2020, notes the following:

“The EKOTON screen, installed in the summer, passed a successful initial inspection. The rakes, located at a distance of about 1 meter from each other, prevent the screen filtering mesh from clogging. Collected wastes remain on the screen filtering mesh for a much shorter period of time compared to the previous one. Consequently, the period of time, when wastes on the filtering mesh can be pressed through by water, is much shorter. Another advantage that could be observed is that the wastes is collected from a screen not with a help of a steel cord, but with a chain made of the same material as the screen itself. This eliminates the possibility of rupture of the steel cord and further interruption in screen operation due to the need of steel cord replacement”.

The article also states that the high efficiency of sewage treatment from all kinds of fibrous and rag materials ensures the stable operation of pumping equipment, which is the most important economic factor. The experts of the Ekoton company, together with the employees of the Budapest Waterworks, continue to constantly monitor the operation of the installed catenary screen to control the effectiveness of the applied solutions and their further improvement.

Case Study: Mechanical treatment complex based on EKOTON bar screens (Plastun port, Primorsky Krai, Russian Federation)

PROJECT – Reconstruction of the section for the heat treatment of round timber at the veneer processing plant in Plastun village, Terneysky district of Primorsky Krai
CUSTOMER – Terneyles JSC
SITE – Local wastewater treatment facilities of a timber processing enterprise
COMMISSIONING – November-December 2019


Terneyles JSC is located in Plastun port, Primorsky Krai, and is an integrated timber processing enterprise. There are also two plants for the processing of round timber — a veneer plant and a sawmill, as well as two enterprises that are part of the structure of Terneyles JSC — a softwood processing plant STS Teknovud CJSC and a hardwood processing plant PTS Hardwood CJSC.

In 2018, the companys’ representatives turned to the EKOTON Industrial Group for help in the choice of equipment for the treatment of industrial wastewater on the heat treatment of wood site.

Project goals

The customer was faced with the task of constructing a treatment plant that would allow to extract the wood fraction from the water used in the wood processing and return the treated water to the production cycle of the enterprise.

The project of treatment facilities was carried out by the investment and construction engineering company ProektStroy LLC, and EKOTON Industrial Group acted as a supplier of mechanical treatment complex based on Ekoton Bar Screens.

Project execution

EKOTON TM equipment was manufactured at the company’s plant in Russia. Since it was supposed to use Bar Screens in non-standard conditions (high temperature of the water supplied to the screens, the content of large inclusions in the effluent, such as tree bark, chips, etc.), the following changes were made to the existing design of RKE EKOTON Bar Screens:

  • Stainless steel was used in the lower fixed part of the screens instead of a plastic slide (idler);
  • A rake positioning system was installed on the coarse treatment screen;
  • The chains on the screens were made entirely of stainless steel without plastic rollers;
  • The control cabinet was equipped with a Modbus RTU data transmission system.

EKOTON professionals carried out the installation of equipment independently simultaneously with construction work. The complex was successfully launched and commissioned at the end of 2019.

Summary and conclusions

The commissioning of the mechanical wastewater treatment complex based on EKOTON equipment allowed the customer to switch to a closed cycle of water use in the production department. This solution is forward-looking for industrial enterprises and allows achieving several positive effects at once:

  • prevention of pollution of natural reservoirs by wastewaters of enterprises,
  • reduction on the costs of achieving maximum permissible concentration for discharge into a reservoir/ municipal wastewater plant,
  • reduction of consumption of fresh water for production processes.

Case Study: EKOTON diffusers at Tesla (Shanghai, China)

SITE – Tube Air Diffusers
EQUIPMENT – Tesla (Shanghai) Co., Lingang Development Zone, Pudong New Area, Shanghai


On May 10th 2018 Tesla (Shanghai) Co., Ltd. was established in Lingang Development Zone, Pudong New Area, Shanghai. The company is engaged in technology development, technical services in the fields of electric vehicles and parts, batteries, energy storage equipment and photovoltaic products. Electric vehicles, technology, wholesale, consulting, commissioning as well as import and export business of the above-mentioned products and supporting services constitutes the business of the company.

Tesla Gigafactory is the largest foreign manufacturing project in Shanghai to date, and it is also Tesla’s first Gigafactory outside of the United States. Tesla has invested over 2 billion USD in the components plant in China in order to localize the supply chain and is preparing to expand the factory’s production capacity.

As EKOTON diffusers has the advantages of stable performance, strong aeration capacity and low energy consumption, the owner decided to use EKOTON tube air diffusers for the local WWTP.

EKOTON diffuser parameters

Outer diameter120 mm (Threaded to DN100)
Total length1020/2025 mm
ModelAPKV-1 / APKV-2
Disperser length940/1945 mm
Dry weight4/8 kg
Design air flow8-25/16-50 Nm3/h


After detailed investigation of the on-site data, aeration tank conditions and blowers, we recommended arrangement of the diffusers accordingly. The installation of Ekoton tube air diffusers was completed on the 30th of May 2019. The equipment operates smoothly since then.

Aeration system length64 r.m.
Air volume of the blowers1200 m3/h (2 blowers, each blower: 20m3/min)
Air volume per diffuser18.75 m3/h/m
Tank bottom coverage10.7% (percentage of the diffuser active area in relation to the bottom area of the tank)
SOTE0.6 m of aerator per 1 m2 of the tank bottom
Distribution of aerators33.5% (SSOTE 6.7% depth 5m)
Pressure loss140 mm H2O

EKOTON tube air diffusers layout

Case Study: EKOTON Tube Air Diffusers at Tianfu International Airport New City (Chengdu, China)

EQUIPMENT – EKOTON Tube Air Diffusers
SITE – International Airport New City, Chengdu Tianfu


Chengdu Tianfu International Airport New City project is located in the Eastern New District of Chengdu, China. The Eastern New District was established on April 28, 2020. On March 4, 2020 Chengdu proposed 308.6 billion yuan (47.7 billion USD) to be invested in the construction of the Eastern New District of Chengdu within the next 10 years. Among them, the investment in 2020 will reach 28.9 billion yuan (4.4 billion USD).

By 2025 major infrastructure and public service facilities will cover the New District of Tianfu International Airport’s aviation hub is going to be completed by that time as well. Strategic emerging industries, modern service industries, legal governance will be established. The permanent population of the district is estimated to reach 800,000 and the regional GDP – 48 billion yuan.

Airport New City, relying on Chengdu Tianfu International Airport, gathers the functions of aviation economy, international finance, international trade, technological innovation, international education and cultural exchange. According to the development plan, 15 municipal WWTPs will be built in the Airport New City. EKOTON tube air diffusers are used at No. 6, No. 9 and No. 15 water plants.

EKOTON Tube Air Diffusers Parameters

Outer Diameter120 mm (Threaded to DN100)
Total Length1020/2025 mm
Disperser Length940/1945 mm
Dry Weight4/8 kg
Design Air Flow8-25/16-50 Nm3/h

Project Overview

Chengdu Tianfu Airport New City WWTP no. 6 is located to the west of Jiangxi River and to the south of the New Airport Expressway. It’s estimated capacity is 40 000 m3/day. It is planned to serve mainly for innovative manufacturing, with the service area of about 1057 ha.

Aeration System Length1 550 r.m.
Air Volume of the Blowers14 040 m3/h (3 in use; 1 stand-by)
Air Volume per Diffuser12 m3/(m3/h/m)
Tank Bottom Coverage10.4%
Distribution of Aerators0.6 m of Aerator per 1 m2 of the Tank Bottom
SOTE47% (SSOTE 6.6% depth 7.2 m)
Pressure Loss80 mm H2O

The 9th WWTP’s capacity is 32 000 m3/day. It is located in the Jiangxi Henan Group West Area on the south side of the Jiangxi River in the Airport Industrial New City. It is planned for economics, high-end industries, hotel services, medical education, administrative offices and residences. The service area is about 1450 ha.

Aeration System Length1 190 r.m.
Air Volume of the Blowers9 000 m3/h (3 in use; 1 stand-by)
Air Volume per Diffuser9 m3/(m3/h/m)
Tank Bottom Coverage13.1%
Distribution of Aerators0.7 m of Aerator per 1 m2 of the Tank Bottom
SOTE49% (SSOTE 6.9% depth 7.2 m)
Pressure Loss75 mm H2O

The 15th WWTP has a design of 30,000 m3/day. It is located to the east of Jiangxi River in the starting area of the Airport Industrial New City, on both sides of the New Airport Expressway, and close to the new Chengdu Airport, which is currently under construction. It is planned for industrial and logistic purposes. The service area is about 581.6 ha.

Aeration System Length1 250 r.m.
Air Volume of the Blowers10 800 m3/h (3 in use; 1 stand-by)
Air Volume per Diffuser10 m3/(m3/h/m)
Tank Bottom Coverage12.7%
Distribution of Aerators0.7 m of Aerator per 1 m2 of the Tank Bottom
SOTE50% (SSOTE 7% depth 7.2 m)
Pressure Loss76 mm H2O

Case Study: Modernization of the secondary clarifiers (Novosibirsk, Russia)

PROJECT – Modernization of secondary clarifiers
CUSTOMER – MUE «Gorvodokanal» Novosibirsk
OBJECT – WWTP Novosibirsk
COMMISSIONING – summer 2019


The municipal company of the city of Novosibirsk “Gorvodokanal” cleans and supplies about 600 000 m3 of drinking water and transports and disinfects about 500 000 m3 of sewage per day. Among consumers, more than 1.8 million residents of Novosibirsk and the region. About 70% of the services provided for them. The remaining 30% are industrial companies. The metropolis ranks third in terms of the length of the water supply system in Russia. Gorvodokanal manages about 3,500 km communications, three water intakes, three pumping and filtering stations and 69 sewage pumping stations and also WWTP.

Since 2007, the company has been implementing large-scale investment programs for the technical re-equipment of treatment facilities. The company has been cooperating with the EKOTON Industrial Group since 1997, during which time mechanical treatment complexes (about 20 rake bar screens, screw conveyors and screw compacting presses) were modernized, penstocks were installed and the aeration system was re-placed. As part of the next stage of modernization in 2019, two sets of equipment for radial secondary clarifiers were delivered – radial suction scrapers IRVO-40.

Project goals

The main objective of the project was to increase the efficiency of sludge removal from secondary clarifiers. The technological condition of the existing equipment at the time of the start of work was unsatisfactory – the suction pumps installed in the 1980s were used. The condition of concrete structures also left much to be desired.

The replacement of equipment was supposed to lead to an improvement in cleaning performance, a reduction in energy consumption, as well as a stable and proper process management.

Project implementation

At the request of the Customer, two radial suction scrapers IRVO-40 with the following design features were produced at the EKOTON plant:

  • an enlarged sludge pipe (sludge collector) with a diameter of 630 mm was used;
  • a new reinforced system of rods (fasteners) was applied between the truss of the bridge and the silt
  • all-wheel drive trolley with planetary gear type;
  • the control unit is equipped with a Modbus RTU data transmission system.

An additional challenge was that, at the request of the Customer, we independently installed the equipment simultaneously with the construction work of the concrete park of the clarifier and the replacement of the discharge tray. Due to the repair of the side part of the clarifier, it was not possible to drive up standard lifting equipment; a crane with a lifting capacity of 250 tons was used. In order to meet the deadlines and not to stop the installation work, one of the two bridges had to be temporarily put on an unfinished side of the clarifier.

Results and conclusions

Despite the difficulties that arose during the installation of the equipment, it was possible to complete the commissioning in accordance with the schedule.

The use of modern technological solutions in the design of equipment ensured high efficiency, energy
efficiency and reliability. As a result of the replacement of existing radial sludge scrapers at the WWTP “Gorvodokanal” in Novosibirsk, all the necessary customer requirements related to maintenance and
repair were achieved.

Case Study: Tannery Plant (Navarra, Spain)

EQUIPMENT Multi-Disc Screw Press Dehydrator MDQ-352C(1)
TYPE OF SLUDGE Tannery wastewater treatment process
DS LOAD 1200 kg DS/day


Sludge from the tannery production waste water treatment plant was filtered with use of a chamber
filter press. A large amount of lime used along with complex operation and low automatization level have
led to dissatisfaction and search for another dewatering technology. Additional aspect to consider was the future plans for the tannery plant capacity increasement, that the new dewatering solution should be able to deal with.


Aſter pilot tests, which were performed in January 2019, Multi-Disc Screw Press dewatering technology was selected for renovation. MDQ unit showed high productivity and dewatering efficiency at the same time with good quality of the filtrate.

A unique feature of MDQ is the ability to increase productivity by installation of additional screws. Taking into account future increasement in productivity, the MDQ-352C(1) with one screw and a free slot for the second one was offered to the Customer with perspective extension to MDQ 352. This has allowed the Customer to reduce initial CAPEX.

In July 2019 the new dewatering system based on Multi- Disc Screw Press Dehydrator MDQ-352C(1) has been commissioned under EKOTON expert’s supervision.


Current Unit's DS Productivity150-180 kg DS/h
Cake DS Concentration35 %
Operation Mode6-8 h/day
Average Polymer Dose4,5-7 kg/1000 kg DS
DS Capture Rate99,6-99,9 %

Case Study: Delivery and Start-Up of the Sludge Dewatering Complex based on Multidisc Screw Dehydrators in Poultry Slaughterhouse (Kutno, Poland)

PURCHASER Nijhuis Industries Central Europe Sp. z o.o.
OBJECT Meat factory, poultry slaughterhouse
SEDIMENT TYPE Excessive activated sludge, initial flotation sludge


Sludges coming from the treatment of wastewater from meat processing services show specific parameters for this type of industry. They contain increased fat amounts and generally understood animal protein, which in turn requires use of dedicated technology for dewatering of this type of industrial sludge.

The sewage treatment plant is located around 20 km from Kutno, in the Łódź province. The initial entering sewage is a mixture of industrial wastewater from the production lines and biological wastewater which is formed as a result of the daily work of the plant.

The main goal of the investment was the construction of the wastewater treatment plant at the newly built production factory and as part of that the supply and commissioning of two independent and fully automated sludge dewatering complexes.

Plant Capacity5 000 m3/day
Sewage TypeIndustrial/poultry
Sludge TypeFlotation + biological
Total Amount of Sludge228 m3/day
Average DS in Sludge5,6 %
Average Weight of Solid Sediments12 845 kg DS/day
Initial Amount85 m3/day
DS in Initial Sludge10 %
Weight of Solid Sediments8 544 kg DS/day
Initial Amount143 m3/Day
DS in Initial Sludge3 %
Weight of Solid Sediments4 300 kg DS/d
DS Content in Sludge Cake22%-26% +/-1%

Work Progress

To determine the efficiency of sludge dewatering, first laboratory tests were performed. Because the plant in which this technology meant to be implemented was still under construction, the tests were carried out in another plant, which had an identical production line and purification technology to the built one. When selecting the device, the experience of EKOTON PRODEKO-EŁK was used as a supplier of comprehensive solutions based on modern technologies.

The analysis of advantages and disadvantages of the use of various sludge dewatering devices at a given facility has led to the selection of the multidisc screw dehydrators (MDQs), whose main advantages are:

  • simple operation,
  • low energy, flocculant, water consumption,
  • very low noise,
  • the ability to work in automatic mode

The scope of delivery included two independent drainage lines. Each of them consisted of a multidisc screw press, an automatic polymer preparation station, a sludge feed pump and a polymer dosing pump.

Multidisc screw dewatering units and the other supplied devices work efficiently and reliably. The
operating parameters of the sludge treatment units in both lines enable them to obtain sludges with the
level of DS up to 34%. Equipped with full automation, it allows the user to optimalise the dewatering process and meakes the sludge management much easier.

Case Study: Industrial Sludge Dewatering at the Beverage Factory (Sucheava, Romania)

TYPE OF INDUSTRY Food and beverage industry
PLANT CAPACITIES 1,3 million litres per year


The Beverage Factory has been treating their wastewater using an external company. Due to high transportation costs, a decision was made to build their own wastewater treatment plant on-site. The full technology was developed for technological and domestic wastewater treatment to safely discharge treated water to the environment. The problem was only in utilization of generated sludge, as its transportation by an external company was of high cost. Hence, EKOTON was invited to develop the technology and supply the equipment for sludge dewatering.


Aſter receiving the enquiry, EKOTON professionals began calculations and selected the best dewatering equipment for the sludge regarding its fl owrate and composition. The flocculant solution preparation station was also adjusted to provide fully automatic operation of dewatering facility. Soon aſt er multidisc screw press MDQ-102C and solution preparation station SMART Mix 2100 was successfully installed and commissioned at the site. Multidisc screw dehydrator was selected considering its advantages before other equipment. With much more lower footprint compared to a decanter centrifuge and a belt fi lter press, it ensures silent and trouble-free operation with no need of periodical maintenance. Additionally, the power consumption is reduced significantly comparing to the centrifuges, and the water consumption – comparing to the belt-filter presses. What is more, even if to compare with other modern dewatering equipment such as screw press, the multidisc screw press still allows achieving of lower flocculant consumption with easier maintenance. Aſter commissioning, the complex operation was synchronized and adjusted to work automatically together with other technological equipment for wastewater treatment. Whenever DAF sludge is collected in the sludge tank, the facility starts the dewatering process that shows high effi ciency regarding to equipment capacity and a moisture content of the dewatered cake, which is then periodically taken and utilized by the external company at a greatly reduced volume achieving low operational costs.

Results and Efficiency

Type of SludgeDAF sludge
Unit Capacity25 kgDS/h
DS Content of the Sludge5,9 %
DS Content of the Cake30 %
Solid Capture Rate> 97 %
Average Flocculant Dose2,5 kg/tDS

CASE STUDY: Production and setting up of a municipal sludge dewatering facility (Biskupiec, Poland)

Aim of work:

The studied municipal wastewater treatment plant is located in Biskupiec, Warmian-Masurian voivodship, Poland. It serves Biskupiec city and Rukławki village. Inlet wastewater consists of household, industrial sewage from nearby meat plants and rainwater. The average capacity is 1 450 m3/d, with the maximum of 1 725 m3/d.

After mechanical and biological treatment, an excess sludge with humidity of approximately 99.7 – 99.8% is generated in amount of approximately 360 m3/d, which is then gravitationally thickened to a dry solids content of 1.0 – 2.0% in an amount of approximately 60 – 120 m3/d. Earlier, the sludge was dewatered on the belt filter press and then utilized partially for agriculture needs as well as distributed to the sludge plots.

The necessity of reconstruction was caused by poor dewatering process efficiency which affected in high humidity of dewatered cake (approx. 10 %). Additionally, existed belt filter press capacity of approx. 60 m3/d was insufficient to process the entire amount of sludge even beside the fact it was operating with high accident rate.

As the company with rich experience in municipal sludge dewatering technology, EKOTON IG was able to offer an appropriate solution and accepted this project for work.

ekoton multi-disk screw press mdq biskupiec poland

Progress of work:

To get acquainted with the case, laboratory and pilot studies were carried out. First of all, flocculation tests were conducted and the optimal process parameters were obtained. Further pilot scale tests allowed to find the optimal dewatering process parameters in real conditions. The results were analyzed and necessary calculations were done which gave EKOTON constructors opportunity to fit and design the best appropriate dewatering technology.

After the old dewatering complex was removed, the new equipment were installed with respect to all client and labor protection requirements. Then it was commissioned and all technological parameters were adjusted to meet the best dewatering efficiency for this kind of sludge.

Average WWTP capacity1450 m3/d
Sludge dewatering facility capacity120-150 m3/d or 1,9 tDS/d (135 kgDS/h)
Average DS content in sludge1,5 %
Average DS content in dewatered cake15-17 %
TSS in filtrate60-260 mg/l
Flocculant dosage9,3 kg/tDS
Manual control time (for 8 h working shift)20 min on adjustment + 30 min on overall maintenance (can be carried out during nonstop equipment operation)
Availability (as a metric of overall equipment efficiency)90-97%

The reconstruction of the sludge dewatering facility at Municipal Wastewater Treatment Plant in Biskupiec allowed to increase its capacity from 60 to 120-150 m3/d.

Despite of extremely low dry solid content in initial sludge caused by its specific composition and poor thickening process efficiency, installed equipment managed to obtain dewatered cake of transportable consistence and allows ta save expenses on further transportation and utilization due to its quantity reduction. The new technology allows to obtain higher dry solids content in cake (up to 17 %) and cleaner filtrate (60-260 mgTSS/l) with fully automatic and reliable operation of EKOTON equipment even in such complicated case, when average dry solids content in inlet sludge is only 1,5 %.

Moreover, implemented technology leads to additional operating costs decreasing due to water, electricity and reagent consumption reduction.

Case Study: Municipal WWPT (Sentishtvan, Hungary)

SIZE OF WWTP 700 m3/day (184 900 GPD)
END USER Northern Hungary regional water and wastewater utility provider, ÉRV Zrt.
CUSTOMER Northern Hungary regional water and wastewater utility provider, ÉRV Zrt.


The client was not satisfied with the existing belt-filter press because of high repair and maintenance costs, therefore they decided to change it during the general reconstruction of WWTP. The client was looking for sludge dewatering solution with low power consumption as well as small footprint to be installed in place of the existing filter press.


After the detailed analysis and comparison with other manufacturers, the client chose our dehydrator. The client was impressed by reliability, low wash water consumption and negligible odour emissions due to the enclosed design of our dehydrators operating in Scécsény and Ózd WWTPs, Hungary. Based on the required dewatering capacity, one unit of MDQ-351 C was installed, while previously installed belt-filter press is stored as a metal scrap in the territory of WWTP. EKOTON specialists actively assisted during all project steps – starting from the development of new sludge dewatering scheme, ending with the replacement of existing facilities with new equipment and pipework installation – making it virtually a turnkey project.


Type of sludgeThickened waste activated sludge
Unit Sludge Supply4-5.3 m3/h (18-23 GPM)
80 kg DS/h (176 lb DS/h)
Feed Sludge DS Concentration1.5-2 %
Cake DS Concentration18-19 %
Operation Time8 h/d
Average Polymer Dose4-6 g/kg DS (8-12 lb/ton DS)
Unit Daily Power Consumption6.5 kW*h