Reference flow in the MFA for which is suitable the technology

190703 - Leachate generated in an old landfill site for municipal solid waste

Incoming input

Leachate from a municipal waste landfill in aftercare phase (capping installed). The pollution load is relatively low

Outgoing output

• Solid sludge sent to disposal, 

• purified leachate treated in the nearest WWTP and

• ammonium sulphate, a by-product used as N-fertilizer 

Technology description

Firstly, at  the entrance of the scrubber, the main flow passes through a settlement phase and a pre-heating chamber. The core step is the stripping process where, moving the pH-equilibrium, is possible to move the ammonia compound from the aqueous to the air matrix. The leachate with low ammonia concentration, respecting the normative limits, can be collected by the sewer system and treated in the nearest WWTP. The addition of sulphuric acid contributes to recover ammonium sulphate from the process. The injection of specific chemicals occurs along the system

Organizative processes to support closing the loops

It is important to exit with the produced ammonium sulphate from the waste definition. It is challenging because of Italian strict approach about End of Waste and by-product. The presence of heat renewable sources available on site can increase the affordability to waste recycling

Practitioners opinion

It is an interesting solution because follow the CE prescriptions: from waste to valuable secondary raw materials. It is a key issue to find out a possible destination of the by-product that it find field application.

Possible limiting factors

Find out recipient(s) for the by-product (ammonium sulphate) that ensures supply demand. The possibility to self-declare a by-product by producer has a certain degrees of risk because of absence of an authorization by competent authorities.

PP’s opinion of the technology

The onsite availability of the heat increase the feasibility of the presented solution, reducing the energetic consumption from the grid; the exploitation of available heat in a new way is a CE example. 

Concept and conclusions how the technology can affect the CE effect

It is interesting to recover a valuable secondary raw material from a leachate according to CE principle. According to the same principle, heat recovery is another suitable solution. Anyway specific assessment of environmental footprint should be produced. 

Is the technology a BAT?

Yes, guidelines for the identification and use of the best available techniques for chemical-physical and biological wastewater treatment plants

Charts, photo, diagrams

References

http://www.studioscsc.it/depuratore_percolato.html