Waste from the integrated water system

[GRI - 103-1], [GRI - 103-3], [GRI - 306-2], [GRI - 306-1],

In the Water Segment, production of waste largely corresponds with the production of sludge from the treatment process, with a minimal portion from sand and screens used in the same process. The former is essentially composed of water, biomass and a portion of chemical substances used for conditioning during drying, which helps to reduce the volumes of waste outputs. Sand and screens derive from pre-treatment of wastewater and contain plastic, aggregates and paper materials. The remainder is composed of residual material from cleaning to maintain systems. This may include sludge from regeneration of cation-exchange resins. Chart no. 60 shows an example of waste streams for the water sector.

Chart no. 60 – Waste streams for the Water Segment companies

Chart 60

Table no. 70 – Waste produced by companies in the Water segment (2019-2021)

water segment waste (t) 2019 2020 2021
total waste 153.465 152.285 176.438
hazardous 116 239 379
non-hazardous 153.349 152.046 176.059
of which sludge, sand and screens 143.316 138.756 166.969
detail by type of processing      
entirely recovered waste 54.992 63.570 110.019
of which sludge, sand and screens for recovery (*) 53.283 59.884 108.620
entirely disposed of waste (*) 98.473 88.715 66.419
of which sludge, sand and screens for disposal (**) 90.033 78.872 58.349
waste-to-energy 801 2.759 2.962
incineration 13.230 16.660 5.242
landfill and other disposal operations 84.442 69.296 58.215

(*) In 2021, 102,760 t of sludge and 5,860 t of sand and screens were sent for recovery.
(**) In 2021, the following was sent for disposal: 50,031 t of sludge and 8,318 t of sand and screens.

Aquaser acts as a broker for certain Group water companies (Acea Ato 2, Acea Ato 5 and AdF), carrying out the pick-up, transport and recovery/disposal of waste (solid and liquid), with identification of final-destination sites for special waste with regard to solid materials, and providing logistical services (pick-up, transport and discharge) for liquid waste that is handed over to authorised plants.