Impact of sulphuric, hydrochloric, nitric, and lactic acids in the preparation of a blend of agro-industrial digestate and wood ash to produce a novel fertiliser

Anaerobic digestate is a waste product of biogas generation which produced in large amounts and, because its high water content, it expensive to store, transport, and spread land. Additionally, special conditions are required for land application minimise the losses nutrients. This material primarily used as source organic matter soil while farmers continue rely on NPK chemical fertilisers, using energy intensive processes. work evaluated use low-pollutant biomass bottom ash an adsorbent decrease availability carbon A number acidification were tested enhance adsorption improve dewaterability waste. The final blend was intended have more balanced nutrient profile offer better performance terms crop growth than alone. severe acidifications sulphuric, hydrochloric, nitric, lactic acids increased twice amount ammonia remained digestate-ash blend. Hydrochloric acid found be best option preparation sorbent, before mixing with digestate, promote dehydration solid-liquid separation. did not reduce active sites ash, stabilisation digestate; addition acidified reduced pH below that thereby reducing volatilisation NH3 from