Case Study: Municipal Wastewater Treatment Plant (Bridge City, TX, USA)



In the plant sludge drying beds for sludge dewatering were used. This method required lots of labor and constant maintenance. Due to this reason, the customer was looking for the efficient and minimal maintenance solution.


On-site pilot tests were carried out, using mobile dewatering unit MDQ-201, to find the best dewatering technology. According to the test results EKOTON offered sludge dewatering complex based on Multidisc Screw Press Dehydrator MDQ-354(2) CL. The complex includes – influent sludge feed pump, polymer feeder, three screw conveyors and service platform.

Type of sludgeaerobically digested excess sludge
Operating timeup to 8 h/day, 3 days/week
Unit sludge capacityup to 9 (18*) m3/h
up to 320 (400*) kg DS/h
Inlet sludge DS content3.5 %
Cake DS contentapprox. 22-23 %
Polymer consumption14.6 l/tonDS
TSS concentration in filtrate200 ppm
DS capture rate99.4 %
*in case of adding two additional dewatering drums.



Case Study: Municipal Wastewater Treatment Plant (Webster, Texas, USA)



The customer had an interest in reducing sludge disposal costs in their municipal wastewater treatment plant by obtaining lower maintenance costs and lower energy consumption. The plant treats wastewater from nearby residential areas and numerous local restaurants and generates about 120 gallons of aerobically digested sludge from their digesters per minute.


On-site pilot tests were carried out, using mobile dewatering unit MDQ-201, to find the best dewatering technology. According to the test results EKOTON offered sludge dewatering complex based on Multidisc Screw Press Dehydrator MDQ-354 C. The complex includes – macerator, polymer feeder and service platform.

Type of sludgeaerobically stabilized excess sludge
Operating time9-10 h/day, daily
Initial sludge capacity20 m3/h
310 kg DS/h
Inlet sludge DS content1.3-1.5 %
Cake DS content16-18 %
Polymer powder consumption8.8 g/kgDS
TSS concentration in filtrate70 ppm
DS capture rateup to 99.7 %



Case Study: Soapberry WWTP (Kingston, Jamaica)

START OF OPERATION – 2020 February


Soapberry WWTP located near Kingston Harbour has been operated since 2004. Biological wastewater treatment process is based on wetland lagoons. The WWTP has not previously had any sludge processing equipment, therefore since the start-up of the plant lagoons have been gradually filled with dry solid particles. As a result, sludge accumulation had impact on biological process efficiency, because of the reduced effective volume of the lagoons. For this reason, customer was looking for the solution to clean the bottom of the lagoons and process the sludge.


The lagoons cover an area of nearly 6 km2. Bottom sludge from the lagoons is removed by remote controlled dredger supplied by Dragflow. For this reason, EKOTON offered Mobile dewatering complex based on Multi-disc Screw Press Dehydrator MDQ-353 C. The complex includes mechanical screen, sludge tank, influent sludge feed pump, polymer solution preparation unit, polymer dosing pump, water tank, water pump and screw conveyors. All the equipment is mounted on the common platform. The complex can be fitted in a standard 40’ container or on a trailer, which allows an easy relocation.

Type of sludgebiologically digested lagoon sludge
Operating timeup to 23 h/day
Initial sludge capacity10-15 m3/h
Inlet sludge DS content2-3 %
Cake DS contentapprox. 23-26 %
Polymer powder consumption1-2 kg/tonDS
TSS concentration in filtrate100 ppm
DS capture ratemore than 99 %

Case Study: Municipal Wastewater Treatment Plant (Argentia, Newfoundland, Canada)

START OF OPERATION – 2019 November


The customer was looking for a low-cost, yet reliable and easy to operate solution for sewage from a construction site of an offshore platform treatment.


Project was carried together with our partner MABAREX. EKOTON offered Multi-disc Screw Press Dehydrator MDQ-102 C, which is the part of the containerized wastewater treatment plant.


Type of sludgeexcess activated sludge from MBR
Operating time6-10 h/d
Unit sludge supply0.5-1 m3/h
Inlet sludge ds content0.5-1 %
Cake DS content15-17 %
Polymer consumption5 kg/ton DS
TSS concentration in filtrate20-100 ppm
DS capture ratemore than 98 %

Case Study: KB Bioenergy, inc. (Akron, OH, USA)

TYPE OF INDUSTRY – Renewable energy


The customer was looking for a solution to replace one of the three existing centrifuges as well as to increase dry solid content, reduce energy consumption and improve operation.


On-site pilot tests were carried out, using mobile dewatering unit MDQ-201, to find the best dewatering technology. According to the test results EKOTON offered sludge dewatering technology based on Multi-disc Screw Press Dehydrator MDQ-354 CL together with service platform.


Type of sludgeanaerobically digested sludge
Operating time23 h/day, 6 days/week
Unit sludge supplyup to 78 gpm
up to 3,276 lbDS/h
Inlet sludge ds content8.4 %
Cake ds content26.5 %
Polymer consumption16.5 lb/ton DS
Tss concentration in filtrate350-500 ppm
Ds capture rateup to 99.4 %

Case Study: Guggisberg Cheese (Sugarcreek, OH, USA)

TYPE OF INDUSTRY – Dairy products
START OF OPERATION – 2018 December


The customer had an interest in reducing sludge disposal costs in their industrial wastewater treatment plant by obtaining lower maintenance costs and lower energy consumption. The plant treats industrial wastewater from a nearby cheese factory and generates about 15,000 gallons of activated sludge from their MBR system per day.


On-site pilot tests were carried out, using mobile dewatering unit MDQ-201, to find the best dewatering technology. According to the test results EKOTON offered sludge dewatering technology based on Multi-disc Screw
Press Dehydrator MDQ-353 C.


Type of sludgeaerobically stabilized MBR sludge
Operating time8 h/day, up to 5 days/week
Unit sludge supplyup to 12 m3/h
up to 230 kgDS/h
Inlet sludge ds content2%
Cake DS contentapprox. 18-20%
Polymer consumption4.0 g/kg DS
TSS concentration in filtrate50 ppm
DS capture rate99.7%

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.