The role of biosolids product and process energy use of water content, based on market externalities: PAPER & PRESENTATION

Panter, K., Consultant, UK


Traditionally sewage treatment plant (STP) is designed with the objective of meeting the final effluent limits in mind and any route for sludge/residuals that occur is often decided by others and sometimes at a later date. Fundamentally, this approach lacks holistic approach and needs to be altered. The recommended approach will be to incorporate the strategy for sludge treatment and disposal simultaneously along with sewage treatment

The traditional approach ignores the actual outputs from STPs and a key role (and true cost) that sludge treatment and disposal /recycling plays in designing a successful STP. Virtually all the BOD load entering from the sewers is either oxidised (high energy use) or converted into sludge (containing energy) in STPs. The sludge so produced has to be converted to a useful form for reuse or destroyed. The sludge contains energy as carbon, and major and minor nutrients.

There are 3 areas to follow that impact on overall energy neutrality and at the same time total economy. These are 3 aspects to analyse: (i) energy flow; (ii) solids flow and (iii) water balance. The first two have been widely studied but the third one is generally ignored. However, the cost of water transport and/or treatment is the major cost of sludge management and is often one of the largest user of energy. The amount of water in the final product of biosolids to be recycled or disposed is driven by local circumstances where the externalities of marketing or processing can differ widely from country to country. This paper addresses that gap in our thinking with worked examples.

First the energy flow in sewage treatment have addressed in 4 scenarios: primary; Primary plus secondary; enhanced primary and 100% secondary. Results from an AECOM study for Sydney water show the energy flows from sewage to digested cake production 1.

Please fill in your details to download the proceedings

For more information about how Aqua Enviro
can help you, contact us...

Aqua Enviro Ltd

T: 0113 8730728


c/o Tidal Accounting, HQ Offices, Radley House, Richardshaw Road, Leeds, West Yorkshire, LS28 6LE

  • By submitting this form, you agree that we may use the data you provide to contact you with information related to your request/submission and other relevant Aqua Enviro services. You can unsubscribe from Aqua Enviro marketing emails at any time by clicking the unsubscribe link in the email. To learn more, see our Privacy Policy