Research methodology and approach

The SLUDGEtreat project include 4 partners: POLIMI (Italy, leader in electro-osmosis and in wastewater treatment technologies, life cycle assessment studies, chemical characterization, academia), FLU (Spain, high tech SME leader in nano-surface deposition technologies, industry), AIN (Spain, leader in nano-materials, coatings, polymeric and ceramic materials, academia), X2 (Italy, leader in manufacturing screw presses, industry).

In reaching the objectives, along the overall SLUDGEtreat project, which will last 4 years, the involved 16 researchers will have the opportunity to move from their company/university to the other partners’ premises in Europe. Through the intense schedule of R&D activities within the Transfer of Knowledge (ToK) programme they will share their capacities, acquire new skills, develop new competences and transfer also their new know-how back to their home organizations, enhancing the economic and scientific European competitiveness.

The exchanged researchers will be also supported by 5 recruited Experienced Researchers, who will be employed through a well-focused recruitment campaign, with advanced experience in:

1) sewage sludge treatment technologies and LCA methodologies;

2) electrode materials and surface analysis;

3) advanced knowledge in material engineering for conductive coatings and surface treatments;

4) novel surface engineering treatments and new niche markets, including assistance and support to testing of materials and machinery.

The interaction among the parties will be characterized not only by intimate research collaboration, but also by sharing the equipment, exchange of personnel and transfer of know-how. A specific ToK Research Teams (formed by Academia and Industry researchers together) will be set up to focus on specific research topics agreed within the ToK plan. The research methodology adopted in the project is based on the following phases:

Phase 1 – Preliminary Analysis

The following aspects related to requirements analysis will be addressed.

– Analysis of:

(i) the state of the art on electro-dewatering processes and technologies,

(ii) of environmental issues/regulations,

(iii) needs of the water industry concerning sewage sludge alternative and sustainable re-uses as biomass and/or as a resource for energy and material recovery.

– Analysis and identification of scenarios: the application scenarios will be mainly focused on sludge electro-dewatering at small to medium size wastewater treatment plants (WWTP), to reduce the amount of wet sludge to be transported to final users/disposal sites by a factor 2, as the dry solid content can easily be increased from 20-25% to 45-50%. Final destinations will also be evaluated with special reference to: (i) reuse of the electro-dewatered sludge in agriculture, with or without co-composting; (ii) reuse of the electro-dewatered sludge in thermal processes, such as fluidized-bed furnaces, pyro-gasification, co-incineration with the unsorted residual fraction of municipal solid wastes, with an in-depth analysis of its energy recovery potential.

– Development of new nanomaterials using mechanical, chemical and physic parameters to identify the best set of all of them. Conductive coatings of oxides and nitrides of transition metals will be developed with different architectures to protect anode against corrosion. Coating materials have to be characterised and, in some cases, the technologies to obtain them. Specifications of operating conditions will be provided by POLIMI and X2 to AIN and FLU that will investigate materials behaviour and identify the candidate one/s for the proof of concept system. Candidate materials will be sent to POLIMI in order to stress their characteristics in lab tests and small scale environmental tests and to provide AIN and FLU with some feedbacks. Using a spiral methodology, the best one will be identified so that fully meets project requirements and the industrial up scaling criteria.

– During specifications definition, lab scale studies on electro-kinetic phenomena will be conducted, electrodes/new material will be instrumented to define characteristics and specifications as inputs to the subsequent phase of system design and development.

Phase 2 – Design and preliminary development of the proof of concept electro-dewatering system

In this phase, basing on the outputs of the previous phase, the whole system architecture will be designed and developed. Moreover, after collection of data coming from lab scale experiments, the system fine tuning will be performed. This will lead to the implementation and release of a first proof-of-concept prototype of the SLUDGEtreat system. The following main aspects will be addressed:

Architectural design of the system basic modules.

– In close connection with Phase 1, a specific methodology will be defined and applied to data obtained at lab scale to foresee performances of the new system, based on flocculation tests; to choose the most suitable polymer and dosing in view of their dewatering in the new machine, filtration-compression tests will be carried out, combined with shearing tests to evaluate performances by mechanical dewatering and electro-dewatering tests to assess the gain with the use of electrical field.

– Design of the basic modules integration in the dewatering system. Integration tests will be performed while integrating the modules.

Phase 3 – Validation phase

In this phase, the following main aspects will be addressed:

– Lab scale Validation: the novel dewatering system will be tested at lab scale first in order to evaluate machine performance and test its potentialities under different streams (sludge or semi-solid waste fed into the system; reject water collected at the cathode, dewatered material at the outlet);.

– Life Cycle Assessment, LCA, methodology will be used to evaluate the global environmental impact of the different sludge management strategies in order to determine the more sustainable approach. Preferential strategies will be selected from the energy balances results. The study will be made in accordance with the international standards (ISO 14040 and ISO 14044). The functional unit will be the treatment of the same amount of sludge, expressed on a dry basis. The LCA study will be carried out by choosing the most suitable impact categories and a choice will be made between different methodologies, such as: Impact 2002+, Eco-Indicator 99 and CML 2001. The LCA study will be carried out by considering well defined boundaries to the system, i.e. from sludge pre-treatment to final disposal (landfill, agricultural reuse, thermal processes with energy recovery).

Work Packages

WP 1


O.1.1. guarantee that the ToK programme is carried out according to the time schedule and budget established, O.1.2. Creation and maintenance of an effective co-ordinated structure, O.1.3. guarantee that the project is managed according to the Grant Agreement between the Consortium and the REA maintaining a continuous link with the REA overall legal, contractual, ethical, financial and administrative issues of the project

Description of work

T.1.1. Project Management: activities to guarantee that the ToK programme is carried out according to the time schedule and budget established; the objectives are efficiently achieved; iii) an effective co-ordinated structure is created and maintained; iv) the project is managed according to the Grant Agreement between the Consortium and the REA, maintaining a continuous link

WP 2


O.2.1. to analyse the current market of sludge dewatering, O.2.1. to define the prototype main validation scenarios

Description of work

T.2.1. Task 2.1 Market analysis and technology state of the art review

This task aims at analysing the current market of sludge dewatering. This analysis is not limited to find existing competitors’ products and solutions/technology/processes, but also aims at identifying the perceived market needs about sludge characteristics for further re-use in different application domains (agriculture, biomass, heating systems, etc.).

T.2.2. Task 2.2 Definition of system main validation scenarios

The Task aims at defining the prototype main validation scenarios, for the validation activities, to be carried out in Task 4.2. Specific application scenarios will be taken into account and selected as validation scenarios, in order to guarantee that the results of validation are representative of real-life systems currently applied in the water treatment sector.

WP 3


O.3.1. Detailed a high-level design of the SLUDGEtreat prototype (the best system configuration), O.3.2. Choose the most suitable coating materials for the anode, performing lab tests on both nano metallic and ceramic materials, O.3.3. Investigate the electro-osmotic phenomena and identify useful parameters (intensity of the electric field, timing of application, energy input, applied pressure).

Description of work

T.3.1. Task 3.1 Architectural system design (led by POLIMI)

Starting from requirements collected in WP2, specifications will be provided and the high-level design of the SLUDGEtreat prototype (the best system configuration) will be detailed. Based on scenarios defined in WP2, high level functionalities will be decomposed into specific ones and allocated to the basic components of the system. Roles of components and their interaction will be textually and graphically specified, and released as design documents. Along the project, design reviews are foreseen. Results of this activity will be part of the D3.1, including a reference architecture and design descriptions.

T.3.2. Task 3.2 Lab-scale studies on nano-materials (led by AIN)

This task aims at choosing the most suitable coating materials for the anode, performing lab tests on both nano metallic and ceramic materials. These materials, which represent a critical success factor, have to be high abrasion resistant, to prevent corrosion due to sludge friction & acid environment. The following RTD activities have already been identified:

1) Materials like Titanium and Magnesium or other high performance steel as well as ceramic, hybrid or fully organic coatings will be studied, taking into account that the best choices have to be compatible also with the electro-osmotic effects and able to enhance them.

2) Nanostructured materials present low surface energy and high mechanical performances andwill be relevant matter of study, in compliance with the chemical and physical properties of the sludge at the different dewatering process steps.

This study is instrumental for the system design and will be reported in D2.4.

T.3.3. Task 3.3 Lab-scale studies on electro-osmotic phenomena (led by POLIMI)

Within this task the electro-osmotic phenomena will be deeply investigated and useful parameters (intensity of the electric field, timing of application, energy input, applied pressure) identified. The parameters selection depends on the chemical (chemical activities of the main substances) physical properties and on its fluid-dynamic aspect in the electro-osmotic chamber. As all parameters are deeply influenced by the dry part of the sludge that change along with the main direction of compression work, the profile of their changing may be a working useful parameter. Within this task the position of the electrodes, their number and geometry, the type of the power whether AC or DC or pulse, will be designed. The study is instrumental for the system design and will be reported in deliverable D2.3 and D2.5.

WP 4


O.4.1. Manufacture all system components (electro-osmotic chamber and anode) needed to build the final electro-dewatering prototype system; O.4.2. Carried out the pilot tests on the proof of concept lab prototype

Description of work

T.4.1. First release of the proof of concept prototype (led by POLIMI)

This tasks aims at manufacturing all system components (electro-osmotic chamber and anode) needed to build the final electro-dewatering prototype system in accordance with the results gathered from the design activities in WP3. All the previous modules will be integrated in the final framework. Integration tests will be performed while integrating the modules. Then, the framework will be integrated into a lab-scale environment, according to the decision taken during the design phases about the platform, the language, and the final deployment. The first full release will be produced and will be tested during validation with real sludge simulating field environmental and operational conditions. Results of this activity will be part of the D4.1.

T.4.2. Validation activities (led by FLU)

As real fresh sludge properties are changing with time, pilot tests on the proof of concept lab prototype will be carried out. After gathering numerical data from lab scale experiments and feedbacks from end user, the first release will be fine tuned and the final system will be released. Design specifications and modifications will be reported and integrated into the second version and final design of the electro-dewatering device. This will be reported in Deliverable D4.3. Moreover the following activities will be performed in order to give indications about the impact of the proposed sludge treatment in terms of greenhouse gas emissions/savings: i) Energy balances related to electro-kinetic sludge dewatering, from sludge production to final disposal. Energy balances according to several scenarios, including the sludge treatment itself and the possible valorisation issues of the end product, based on results obtained from WP2, WP3.

WP 5


O.5.1. Dissemination of the achieve results and innovation by the team; O.5.1. Preparation of detailed training materials

Description of work

WP5 will include all activities needed to prepare the SLUDGEtreat training materials for the ToK activities to be carried on by the ToK Teams, such as dissemination & outreach activities.

T.5.1 Dissemination and outreach activities (led by POLIMI and AIN)

All partners will be involved in this task and all activities are detailed in sections 5.2 and 5.3 targeted to disseminate the achieve results and innovation by the team.

T.5.2 Training Materials (led by POLIMI and AIN)

Detailed training materials will be prepared and know-how transfer activities will be arranged for the benefit of the industrial partners. Training material is targeted to the professional users of X2 and FLU who have to be trained and drilled in the proper use of the technology developed during the project.