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: Sludge Dewatering Complex for Automotive Manufacturer (Fenice, Poland)

CAPACITY OF SLUDGE 10 m3 per day, 7% DS
CUSTOMER Fenice Sp.z.o.o.


Complex mix of municipal and industrial waste waters, including wastes from paint and other various manufacturing sites aſt er sedimentation was dewatered using decanter centrifuge. High operational costs (cake removal, flocculant, electricity) lead to dissatisfaction and searching for other dewatering technology. Mobile out-door design of centrifuge also didn’t allow whole year operation that resulted in some discomfort.


Aſt er pilot tests made in 2017, the chamber fi lter press GK-8.230.20-H (fi lter area 230 m2, cake thickness 20 mm, plate dimensions 1500 x 1500 mm) with whole set of linked technological equipment: feeding pumps station, cloth regeneration station, operational platform was installed on site. All equipment was chosen, delivered and mounted by Ekoton. During August 2019 commissioning of dewatered site was made by Ekoton specialists. The fi lter press and linked equipment were mounted in the hall simultaneously with installation of cake removal system, that allows all-year operation. One of the most valuable preference of presented technology is possibility of sludge dewatering without any reagents adding.


Type of sludgeMix of municipal and industrial
waste waters with
wastes from paint site
Unit Productivity10 m3 per day
Feed Sludge DS Concentration7 – 8 %
Cake DS Concentration27 – 30%
Flocculant / Reagent Adding0
Filtration Pressure6 bar
Operation Time12 – 14 hours per day
Fenice, Poland

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. Dewatering at the sugar production plant. Gorochiv, Ukraine


EKOTON Industrial Group engages in production and supplying wastewater treatment plants with equipment since 1995. Over the years of work, the equipment assortment has constantly grown – dewatering and filtration of sludge and slurries are among company development directions. Today EKOTON produces multi-disc screw and roll presses, belt filter presses, chamber-membrane filter presses. The first and the second equipment are better for wastewater sludge dewatering, while the chamber-membrane filter press is more used for technological slurry filtration.

At the end of 2016, PE “Agro-Express-Service” applied to EKOTON company with the task of chamber filter presses production for filtration of first carbonated juice slurry in Horokhiv Sugar Plant, Volyn oblast, Ukraine. Bankruptcy procedure, owner replacement, a part of metallic installations and equipment removal from the plant have made some complications. In fact, reconstruction of all technological process stages have been accomplished before the season of work has started. Filtration site was dismantled, there were no basic equipment, pumps, tanks, or cake removal machinery.

Customer – Horokhiv Sugar Plant

Activity – Sugar production from sugar beet

Features – Slurry of first carbonated juice

Before – Equipment was dismantled


From the technical point of view production of filter presses was needed for a sugar plant with 8000 tons of beets per day capacity and density of first carbonated juice slurry of about 1,18 1,2 g/cm3. Together with technical plant specialists, a joint technological solution was made based on implementation of three chamber filter presses with area of 170 m2 and cake thickness of 50 mm each. A technological chart of filtration site with all necessary equipment: slurry feeding and filtrate discharging, cake washing, cake blowing, water and acid filtering cloth regeneration were also agreed. It was decided to use a belt conveyors for cake removal with unloading into the dump truck.

Work description:

The technological production cycle including individual design of documentation took 6 months. After equipment delivery, the installation of the filter presses under EKOTON expert supervision was began. Simultaneous assembling of equipment, operation platforms, building constructions was one of the main features of the work. For the same reason it was decided to made cabling of chart right on the site. The total time of the work including installation, cabling, connecting, programming with all chart adjustments was more than 2 months. It is important to note that the successful result of the work was achieved only through joint work of the specialists from the plant and EKOTON IG as well as assembling company.

ekoton chamber filter press

Gorokhiv Project Data

Plant capacity8000 tons of beet per day
Actual productivity6300 – 6500 tons of beet per day
Operation mode24 hours per day
Slurryslurry of first carbonated juice
Slurry density1.18 – 1.2 g/cm3
Slurry capacity50 – 60 m3/h
Sugar content in filtering cake0.02 – 0.04 % of beet weight
Filtering cake moisture35 – 40 %

Technological and financial viability of juice and slurry of carbonated juice filtration using chamber-membrane filter presses are well known. Low sugar contents in filtering cake (up to 0.02 % of beet weight) concurrently with low level of washing filtrate dilution with water (1… 3 %) are the main and the most valuable benefits. The washing filtrate on the plant is taken on lime slaking so there is a possibility of additional cake washing for an extra sugar elution although the filter press valve-collector system also allows to methodically carry out two-stage cake washing with separate filtrate discharging depending on dissolved solid content.

While the actual amount of beet processing is 6300-6500 tons of per day, three filter presses are working with prolonged interruptions between cycles. Common operation cycle of first carbonated juice slurry filtration can be divided into three periods with approximately equal durations – filtration itself, cake washing and cake removing. Filter press clamping/unclamping, tray operation, cake blowing are significantly shorter. Such time distribution allows to organize three filter press operation in a sequence – only one slurry feeding line and only one washing feeding line are used in the scheme at the same moment. Control system of each filter presses “knows” about the state of two others and doesn’t start corresponding operations until it receives a permission from filter presses control systems together with signals from level gauges in corresponding tanks.

It should be noted that efficiency and productivity of first carbonated juice slurry filtration is significantly depends on the maintenance of the optimum capacities of feeding pumps, cake washing pumps and cake removal devices. For example, previously installed pump for cake washing had too low feeding (up to 5 m3/h with pressure of 2 bars) which led to long and poor process efficiency. As a result, productivity decreasing and high sugar content in filtration cake were observed. After the pump replacement by more powerful one was done, washing process began to run in a normal mode with a flow of 25-30 m3/h at a pressure of 6 bar.

ekoton chamber filter press

Sugar plant operates seasonally without interruptions, weekends and possibility to make long-time repairs or service. All stages in technological scheme are of the same importance and filtering of the first carbonated juice is only one of them. Well-adjusted filter press type, coherency in technological decisions, adjustment of optimal operating parameters at commissioning – all this together can guarantee stability of EKOTON equipment operation in overall picture of sugar plant technology.

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

Case Study: Municipal WWTP (Szécsény, Hungary)

SIZE OF WWTP 2000 m3/day (528 300 GPD)
END USER Northern Hungary regional water and wastewater utility provider, ÉRV Zrt.


The client had frequent maintenance issues with their belt-filter press, therefore they decided to change it during the general reconstruction of WWTP. However, no belt-filter press manufacturer could guarantee more than 18 % DS content of sludge cake.


EKOTON performed on-site pilot tests with a small MDQ model and achived 18.5-20 % cake DS content. The client was satisfied with the results and decided to purchase our equipment. Based on the required dewatering capacity, one unit of MDQ-353 C was installed. Previously installed belt-filter press is stored as a metal scrap in the territory of WWTP.


Type of sludgeWaste activated sludge from SBR
Unit Sludge Supply12-18 m3/h (53-80 GPM)
210-230 kg DS/h (463-507 lb DS/h)
Feed Sludge DS Concentration1-2 %
Cake DS Concentration18-22 %
Operation Time10 h/d
Average Polymer Dose4-6 g/kg DS (8-12 lb/ton DS)
Unit Daily Power Consumption25 kW*h

End User’s Comment

Since the comissioning, the performance of EKOTON multi-disc screw press dehydrator MDQ-353 C has been stable and with no issues. With an average feed DS content of 1 %, the cake DS content is 18-22 % while maintaining the required filtrate quality. Control cabinet is equipped with a touch screen which enables setting operational parameters both for the dehydrator and a sludge pump. Operation of the dehydrator is fully automatic, therefore it requires no attention of an operator. Besides beeing almost noiseless, the performance is also reliable and faultless. Over 3-year operation period, only wash water hoses have once been replaced.

Case Study: Industrial WWTP (Kerry Ingredients & Flavors, Savanah, GA, USA)

TYPE OF INDUSTRY Food and beverage industry


In this plant sludge from DAF-unit and MBBR reactor was stored on-site in tanks and its utilization was outsourced to an external company. Due to expensiveness of such service, it was decided to build a local dewatering facility to reduce sludge volume and its disposal cost.


EKOTON company offered a sludge dewatering solution based on one multi-disc screw press dehydrator MDQ-353 C. Other auxiliary equipment including a polymer solution preparation unit and pumps as well as piping was supplied by our local partners, assembled by the customer and commissioned by EKOTON representatives to meet the highest dewatering process efficiency.

End User’s Comment

Since the comissioning, the performance of the dewatering equipment has been stable, highly efficient and with no issues. High dewatering efficiency resulted in significant sludge volume reduction, so the construction of the local dewatering facility has paid off very quickly.


Type of sludgeMixture of waste activated sludge
and DAF sludge
Unit Sludge Supply10.8 m3/h (47.6 GPM)
216 kg DS/h (476 lb DS/h)
Feed Sludge DS Concentration1-2 % (up to 4 %)
Cake DS Concentration16-17 %
Operation Time16-20 h/d
Average Polymer Dose5 g/kg DS (20 lb/ton DS) of liquid

Case Study: Municipal WWTP (Ozd, Hungary)

SIZE OF WWTP 5400 m3/day (1 427 000 GPD)
END USER Northern Hungary regional water and wastewater utility provider, ÉRV Zrt.
CUSTOMER VEOLIA Water Solutions & Technologies Magyarország Zrt.
START OF OPERATION September, 2015


During the preparation of Ózd WWTP construction project, engineering department of one of the leading companies in the field of wastewater treatment was looking for an effective sludge dewatering solution with low power consumption as well as small footprint.


After the detailed analysis and comparison with other manufacturers, the client chose two MDQ-352 C units. During the design stage, EKOTON specialists actively assisted in the development of sludge dewatering scheme.


Type of sludgeThickened waste activated sludge
Unit Sludge Supply7-7.5 m3/h (31-35 GPM)
140-150 kg DS/h (309-331 lb DS/h)
Feed Sludge DS Concentration2 %
Cake DS Concentration18-20 %
Operation Time6-7 h/d
Average Polymer Dose4-6 g/kg DS (8-12 lb/ton DS)
Unit Daily Power Consumption9-11 kW*h