METHOD FOR PROCESSING SEWAGE SLUDGE FROM NITROCELLULOSE PRODUCTION Russian patent published in 2024 - IPC C02F11/14 

FIELD: environmental protection.

SUBSTANCE: invention can be used to obtain mineral additives for application to soils during reclamation work, as well as for use in floriculture and cultivation of depleted soils. When processing sewage sludge from nitrocellulose production, the wet nitrocellulose sludge is treated with an agent solution and mixed. Sewage sludge is dewatered to a moisture content of at least 50%. The agent is loaded into an aqueous solution, which is sulphuric acid with a concentration of 30 to 40 wt.%. The content of nitrocellulose in the reacting mixture is no more than 10 wt.%. Perform constant stirring in the temperature range from 20 to 30 °C for at least 60 minutes. The suspension is washed on filters. Washing is carried out with distilled water until the pH reaches 6.5 to 7.5 units, obtaining solid and liquid phases. The solid phase - destroyed nitrocellulose molecules and calcium sulphate - is sent for further calcination in a sand bath at a temperature of at least 250 °C, with production of mineral soil additives. The liquid phase - water-soluble metal salts, sulphuric acid and nitric acid reduction products - is sent for disposal.

EFFECT: vegetation growth in the reclaimed areas is accelerated.

1 cl, 1 dwg, 14 tbl