Feed Conditioning

The optimisation of sludge treatment by conditioning of feed solids.


This research study proposes to examine the optimization of Autothermal Thermophilic Aerobic Digestion (ATAD) for the treatment of municipal sludge, through pre-treatment of the feedstock. The literature indicates a number of potential methods for optimizing the ATAD process however it appears that research in this area is limited. This project involves direct collaboration between the Institute of Technology, Sligo and the University of Limerick.

The Research Team

Dr. John Bartlett Principal researcher Department of Environmental Science, IT, Sligo.

Dr. Duncan Martin Associate researcher Department of Chemistry & Environmental Science, University of Limerick .


Project Biosolids 5 (PRTLI-Cycle 2, Control of sludge quality through optimization of sludge treatment technologies), at the Center for Sustainability, is currently examining the effect of variable starting (sewage) sludge qualities and sludge treatment conditions on the quality of the Biosolids produced in aerobic and anaerobic digestion systems (Dr. John Bartlett).

Further work is indicated on feed sludge treatment for superior anaerobic (AD) and ATAD operation. The literature indicates a number of potential methods for optimizing gas production and solids removal by breaking down cells in sewage sludge feed. No research study to date has examined this issue.

Project Details

The aims of this project are to examine the effect of feedstock pre-treatment on the aerobic digestion of sludge, and to define key quality parameters of such feedstocks that affect their treatment by ATAD.

A pilot plant system for the ATAD treatment of sewage sludge is proposed in addition to replicate bench-scale systems, to assess contiguously the differences between unconditioned and conditioned feedstock. Methods of feedstock pre-treatment to be investigated shall include; ultrasound; mechanical disintegration; thermal hydrolysis and ozonation.

Analytical profiling, using key parameter will be carried out. The effect of feedstock composition on the treatment process will be investigated in line with previous and current work on sludge undertaken at IT Sligo and elsewhere. Parameters studied will include energy balance, solids destruction, toxin destruction and pathogen removal.