The EPA research report referred to, which was published in 2014, examined the future management options for the collection, treatment and disposal of sludge derived from domestic wastewater treatment systems. One of the recommendations included the need to consider alternative sludge recycling or disposal routes, such as incineration, recycling to energy crops, pyrolysis or the export of dried biosolids against a background of increasing volumes of sludge deriving from both municipal and domestic sources.
Irish Water published its National Wastewater Sludge Management Plan (NWSMP) in 2016. The NWSMP outlines a strategy to ensure a nationwide standardised approach for managing wastewater sludge over the next 25 years. It sets out proposals for the investment in future treatment, transport and reuse or disposal of such sludge and it references the recommendations in the EPA research report. It identifies reuse on agricultural land as the preferred outlet in the short to medium term but commits to examining alternative options to reduce the current dependence on such reuse.
I understand that Irish Water will carry out a feasibility study into the identification of viable alternatives, including detailed consideration of thermal treatments, before the next review of the NWSMP which will be due in 2021.