FIELD: chemistry.
SUBSTANCE: invention relates to waste sewage treatment methods and can be used in producing fertiliser. In the method of treating sewage sludge, dehydrated solid biological or organic sewage sludge is conditioned. Said sludge is then treated with an oxidant. The obtained mixture reacts with concentrated sulphuric and/or phosphoric acid and an ammonia source or with a melt or salt of ammonium sulphate/phosphate in hot or molten state. Temperature, pressure and holding time are controlled. The fertiliser obtained using this method contains more than 8 wt % nitrogen and preferably 15 wt % nitrogen.
EFFECT: possibility of producing non-toxic and safe-to-handle fertiliser at city sewage treatment facilities.
26 cl, 2 ex, 10 dwg
