Patent ID: 6056880
Filing Date: 2000-05-02
Classification: C02F

Abstract:
A process for treating a waste sludge of biological solids comprising:blending the sludge with an acid, the sludge having a solids content of greater than 7%;mixing an oxide-containing chemical with the blended sludge so as to cause a reaction which elevates a temperature of the sludge, said oxide-containing chemical selected from the group consisting of: calcium hydroxide, sodium hydroxide, potassium hydroxide, lithium hydroxide, calcium oxide, sodium oxide, potassium oxide and lithium oxide;pressurizing the mixed sludge to a pressure of greater than 14.7 p.s.i.a. for a period of time of no less than 15 seconds, said step of pressurizing comprising:passing the mixed sludge as a flow into a pipe, said pipe maintaining the mixed sludge at the pressure of greater than 14.7 p.s.i.a., said pipe having a length such that the flow of the mixed sludge takes longer than 15 seconds to pas through said pipe; andheating the mixed sludge as the flow passes through said pipe by applying a magnetic field around said pipe as the mixed sludge flows through said pipe; anddischarging the pressurized mixed sludge.