Technology Offer
Title:
Advanced mechanical separation and dewatering of coarse particles from raw sewage influents
to small sewage treatment plants (Ref: 10 AT 0106 3IXQ )
Abstract:
An Austrian SME developed a simple and cost-effective machine to separate coarse particles from
raw sewage before the biological treatment step. A "pelletising-strainer" can be installed in an
existing continuous sewer pipe. Substitution for voluminous settling tanks or screen devices and
avoid costly disposal of primary sludge. It can be used with small waste water treatment plants and
pumping stations. Partners are seeked for technical cooperation, financial support and commercial
agreement.
Description:
The Austria developer of the technology is an accredited test and inspection office with an
interdisciplinary staff for the development, design and inspection of small waste water treatment
plants. The company has 35 years of experience in research and the practical application of
decentralised sewage treatment plants and sewage purification systems.
The present situation:
Separation of suspended solids from influents of waste water treatment plants is an essential
requirement for a stable and cost-efficient subsequent biological purification process. Whereas
medium and large plants are frequently provided with automatic screen and sieve devices in open
channels such machines are economically inefficient for small sewage works (e.g. less than 500
personal equivalents). There are no optimal solutions for this purpose with regard to high
construction volumes and sludge quantities for disposal settling tanks. It would be advantageous to
replace conventional settling tanks and the mechanical pre-treatment step due to their voluminous
construction and the need of periodical disposal of huge quantities of digested sludge.
A new alternative:
The technology consists of a screen basket installed in a sewage pipe from which solids exceeding 3
mm in size are separated and delivered up to a pellet press by a charging screw with a 400 V AC
gear motor. Solids arrive in the pellets chamber and are squeezed and extruded out through e.g. 5
mm wide holes as small pellets. These pellets continuously fall down into a steel container that
gathers the pellets over a required period (e.g. half a year) before disposal, local composting or
used for energy recovery. Aerobic digestion can take place continuously reducing volume due to
low water content of the pellets and their coarse material structure.
The whole electric powered machine (Diameter app. 60 cm, High app. 160 cm) can be assembled
completely in a subsurface chamber and the “Pelletising-Strainer” has many advantages in a
mechanical pre-treatment process for small and medium waste water treatment plants.
This technology addresses the need to separate coarse particles out of the raw waste water stream
in order to avoid generation of anaerobic sludges and putrescence processes. Solid wastes for
disposal can be reduced to a minimum.
The "pelletising – strainer" technology is an economic alternative and has a wide field of application
in small waste water and sludge treatment systems as well as for industrial waste use and
addresses the world wide trend and construction of decentralised waste water and sludge disposal.
Preferable fields of application for devices are:
1) Small waste water treatment plants from 50 to 2000 (5000) person equivalents.
2) Pumping stations for raw sewage (no plugging and braiding)
3) Screening coarse particles from faecal sludge in case of cesspool evacuation (facilitate further
sludge treatment ant recovery)
As a research and development institution the company is looking for a financially strong partner to
realize the project:
1) Financing the patent application throughout Europe / world-wide
2) Assembly of an upgraded prototype of the field-tested prototype
3) Determination of final design and dimension criteria based on long time-testing
4) Evaluation/ estimation of the market potential in Europe/ world-wide.
5) Industrial production and introduction to market
6) Selective distribution of this innovative product
Compact and economical mechanical pre-treatment of raw waste water and sludges.
Innovations and advantages of the offer
The main innovative aspects of the technology are:
1) Mechanical pelletising of solids in place of washing and squeezing to screenings leads to less
water content and waste volume in total.
2) A substantial reduction of organic load of waste water for subsequent treatment.
The main advantages are:
1. No settling chamber and disposal of primary sludge needed.
2. Organic load of sewage is lowered so that subsequent biological treatment step can be
minimised due to the conversion of organic solids into mechanical dewatered pellets
3. Solids undergo a high pressure dewatering process which both reduces sludge disposal volume
and facilitates its aerobic digestion.
4. Avoids the costly disposal of primary sludge.
5. No above-ground building for encasing the machine is necessary as compared to existing screen
devices.
6. Subsurface installation.
7. Mobile operation for special needs (e.g. sludge disposal in decentralised systems) possible.
8. Waste volume is minimised and organic load of waste water is reduced due to high dewatering
and squeezing of coarse suspended solids.
9. Production of faecal sludge in small waste water treatment plants can be avoided totally and
screening volume reduced and the subsequent biological treatment step discarded
10. Pellets can be used for energy generation (combustion).
Current and Potential Domain of Application
Compact device for mechanical pre-treatment of raw waste water and sludges.
Current Stage of Development
Available for demonstration - field tested
Exploitation of RTD Results
Private Research
Collaboration Type
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Financial Resources
Testing of new applications
Adaptation to specific needs
Assembly
Engineering
Technical consultancy
Maintenance
Comments
- Type of partner sought: Industry, Multiplier, Financing.
- Specific area of activity of the partner:
Manufacturer of stainless steel devices in the field of waste water and sludge treatment.
- Task to be performed by the partner sought:
Testing and evaluation, prototyping and industrial manufacturing, sales and distribution and/or
financing