The dynamic growth of a large biogas plant in Cleveland, Ohio (USA) prompted the search for increasingly efficient solutions for dewatering sludge generated during biogas production. In response to these needs, and in cooperation with ESMIL, a trial of a new technology – the xJD roller press – was initiated to evaluate its effectiveness under real operating conditions.
Facility overview
The biogas production plant in question processes sludge originating from food industry facilities and other industrial sectors located in northeastern Ohio. As such, it plays a key role in the production of renewable energy in the region. Through the anaerobic digestion process, it converts organic waste into methane, which is then used to generate electricity, heat, and organic fertilizers.
It utilizes the anaerobic digestion process to transform organic waste into methane gas, which is used for the production of electricity, heat, and organic fertilizers.
Need innovation? It’s time for ESMIL!
At Esmil Group, we go beyond conventional thinking – innovation is our driving force. Whether we’re developing new technologies and equipment or refining proven solutions, we believe there’s always a way to do things better. That’s why we constantly seek ways to improve efficiency, eliminate operational issues, and meet the rapidly evolving needs of the industry.
The introduction of the xJD roller press to the U.S. market presented an excellent opportunity to test this innovative technology in practice -on actual sludge from the anaerobic digestion process. The results show that we’re heading in the right direction.
xJD Roller Press – The key to optimizing the sludge dewatering process
The xJD roller press was commissioned at the plant to evaluate its effectiveness as an optimal technology for dewatering abrasive sludge generated during biogas production. At the same time, it was decided to assess whether higher dry solids content and improved filtrate clarity could be achieved – while maintaining high operational efficiency of the equipment.
Initial trials, conducted on sludge with an average dry solids content of approximately 6.5%, delivered very promising results. Using only polymer, the xJD roller press enabled the production of a sludge cake with a dry solids content of 23–25%. Simultaneously, the clarity of the filtrate improved significantly, reaching levels as low as 800 mg/l at roller speeds ranging from 0.5 to 1.4 rpm.
But we didn’t stop there – using an additional coagulant delivered even better results:
- the dry solids content in the sludge cake increased by another 2–3%,
- the dewatering process efficiency improved by up to 40%,
- the suspended solids concentration in the filtrate dropped to around 400 mg/l.
A technology that makes a difference – advantages of the xJD Roller Press from ESMIL
The carefully engineered design of the xJD roller press makes it an excellent solution for dewatering challenging sludges, such as those produced in biogas plants. What sets it apart?
- Ability to effectively dewater difficult sludges rich in fats, oils, abrasive materials, minerals, or fibers – without the risk of abrasive wear,
- High dewatering efficiency – depending on sludge characteristics, it can produce a cake with dry solids content of up to 65%,
- Self-cleaning roller design – prevents clogging and eliminates the need for wash water,
- Low energy consumption – the total installed power of the main dewatering unit is only 2.2–3 kW, significantly reducing operating costs,
- Minimal maintenance requirements – the low roller speed (up to 1.5 rpm) reduces wear, vibrations, and noise, while the simplified design ensures easy service access without the need for special tools or qualifications,
- Compact and modular construction – small footprint, fully enclosed housing, and the option for containerized or trailer-mounted installation,
- High reliability and operational safety – built-in safety systems protect the unit from overflow, configuration errors, or drive overloads.
Thanks to its numerous technological advantages, the xJD roller press is a modern, efficient, and cost-effective solution that excels in dewatering both municipal and industrial sludges – even those that are particularly challenging.
Conclusions – Concretebenefits of using the xJD Roller Press in the biogas Industry
The combination of polymer and coagulant has proven effective in achieving higher sludge cake dryness, significantly improved filtrate clarity, and increased overall process efficiency.
Engineered to handle abrasive materials and the demanding sludge conditions typical of biogas production, the xJD press ensures stable, efficient, and continuous operation. Its advanced design makes it a modern, high-performance, and cost-effective solution for sludge dewatering – ideal for facilities focused on maximizing efficiency and resource recovery.
