Method and plant for processing contaminated waste

A method for processing a solid municipal waste material, comprising the steps of:

• (a) municipal waste and limestone crushing, separation of the ferrous metals, mixing crushed waste with powdery limestone for preparation of pyrolysis mixture in weight ratio, depending of chlorine contents in municipal waste;
• (b) drying of specified pyrolysis mixture in steam dryer, using steam of the recovery boilers of final chimney gases and pyrolytic gas;
• (c) two-stage pyrolysis of exsiccated pyrolysis mixture of municipal waste and dielectric factions of the scrap, entering from units for processing of electronic, electric and cable scrap due to the motion along rotating drum of the furnace of pyrolysis in the beginning with simultaneous neutralization by powdery limestone excreting hydrogen chloride and reception of the calcium chloride, but then with reception of pyrolysis gas and solid pyrolysis remainder due to of the heating by final chimney gases of the combustion chamber, located below;
• (d) condensation of the pyrolytic gas with the following separation on water phase, entering for blowing off the organic admixtures by hot air coming after cooling of slag and organic phase, used as goods fuel and fuel for auxiliaries;
• (e) washing pyrolysis solid remainder taken out from rotating furnace of pyrolysis along with ash and crushed slag, entering from landfill blade of heat power station by water phase of the pyrolytic gas condensate and water after air clearing from the remainder of the dust of dielectric fraction of electronic scrap for dissolving of the calcium chloride and ions of the heavy metals extraction, including radioactive, from voids of the solid particles of waste with the following clear of washing water from heavy metals by adsorption on coal or coke and electric coagulation;
• (f) centrifuge process of the washed solid remainder of pyrolysis of municipal waste, ash and slag of the heat power station with sending of received filtrate for cleaning from heavy metals by adsorption on coal or coke and electric coagulation, but solid remainder of pyrolysis, ash and slag—to incineration in combustion chamber;
• (g) incineration of the washed solid remainder of pyrolysis, afterburning of fuel remainder, being kept in ash and slag, incineration of gaseous and liquid products of pyrolysis and residual gas, carbon oxide (CO) afterburning to carbon dioxide (CO2), reception of the slag with lowered contents of fuel remainder, providing of qualitative production of slag-concrete and chimney gases, the following heat utilization specified gases and slag in other technological processes;
• (h) generation of the low pressure steam in steam recovery boilers due to heat utilization of final chimney gases and pyrolytic gas for drying of pyrolyzing mixture in steam dryer, liquid fuel heating before feeding in combustion chamber and heating of unit's desorber for manufacturing of carbon dioxide from final chimney gases;
• (i) feeding of the steam recovery boilers is realized by own condensate, additional feeding—by demineralized water, entering from the water treatment unit;
• (j) constant partial withdrawal of cleaned from heavy metals washing water for manufacturing of the dry calcium chloride due to the drying process by final chimney gases;
• (k) cooling of the slag and dispatch it to consumer or for production of slag-concrete products, moreover, all cooling air then is completely used in combustion chamber;
• (l) thermohumid processing of slag-concrete products by humid chimney gases after drying the calcium chloride in mixture with vented steam of the extractor for finishing up relative moisture of chimney gases to 100%;
• (m) electronic, electric and cable scrap (the outdated television sets, tape-recorders, telephones, slot machines, computers, cables, wires and the other products) enters for processing wholly, desintegrating in shredder, and its debris are crushed in speediest impact-rotary disintegrator of the first stage down to size 2-5 mm and are going for classification in screening drum, where dividing by partition size;
• (n) particles of the material more than 5 mm return to the repeated pulverizing in speediest impact-rotary disintegrator of the second stage, and then in screening drum again. The particles less than 5 mm going in electromagnetic separator, where dividing in two factions. The driven out particles of the magnetic ferrous metals taking out into the scrap-yard. Remained non magnetic faction by fine layer is going to horizontal conveyor;
• (o) moving on conveyor non magnetic product drying from si superficial humid and is warming, for example, by quartz lamps with nickel-chromium spiral, infrared lamps or other way. Then dried and warmed non magnetic fraction enters in drum of corona-electrostatic separator, where divides on dielectric fraction, semi-product and electrically conductive metallic fraction;
• (p) dielectric fraction (plastic, wood, fiberglass, organic resins, rubber etc.) is going to mixing ejector, mixing with air, given by high-pressure fan, enters in cyclone, but then M by screw feeder is loading in the furnace of pyrolysis. The worked-out air from cyclone is going to the scrubber, where it is cleaning from the remainder of the dust due to the water irrigation, entering from water treatment unit, but then returns in to transport system;
• (q) semi-product (basically not opened locked particles of the metal and plastic) similarly to dielectric fractions enters in mixing ejector, mix with air, given by high-pressure fan and enters in cyclone, whence it again returns in crown-electrostatic drum separator for the repeated processing. The used air from no cyclone by fan is going in the scrubber, where is cleaning from the remainder of the dust due to water irrigation, entering from water treatment unit, and then returns in to the transport system;
• (r) metallic fraction, presenting itself polymetallic concoction of the non-ferrous metals, fortified by the platinum-group metals (platinoids), gold and silver, leaves to factories, where it separates to chemically pure metals.