2 ОРГАНИЗАЦИЯ И МЕТОДИКА РАБОТ - Courrier international

11.3.3.2 Stage of washing of transformer (condenser) with methylene chloride
After draining the transformer (the condenser) must be rinsed from the inside up to environmental
requirements to be able to disassemble and recycle its components
To remove the liquid layer PCB with the inner surfaces of the transformer (condenser) it served a pair of
methylene chloride from the tank with a jacket E1, a cube-vaporizer.
Solvent vapors, condensing the contaminated items, and dissolve and wash away the remnants of PCB.
Contaminated with methylene chloride by gravity back into a cube-evaporator E1.
Heating and evaporation of methylene chloride by circulating hot water fed into the jacket vessel E1. Hot
water circulation pump is H3, heated water in heat exchanger T2.
Treatment process is repeated several times, washed from the transformer PCB accumulate in the tank E1.
At the stage of clearance transformer must be cooled to remove heat of condensation of methylene
chloride. For this heat chamber is transferred to the cooling mode by blowing unheated air fed fan B2.
Control over the amount of methylene chloride is circulating on the return flow from the transformer
(condenser) of condensate, is 100-150 l / h.
Methylene chloride vapor condensation inside the transformer (condenser) is at a temperature of 44-48 °
C and pressure of 0,3-0,5 bar. Uncondensed pairs of methylene chloride enter the air-cooled condenser
T3. He served in the air blower B3.
If necessary, can be connected condenser T4 / 1,2-cooled refrigerant with a temperature of minus 50-
70oC. Condensate is fed into a transformer (condenser) for irrigation of the active part.
The process of neutralization of the transformer (condenser) is completed when the PCB concentrations
in runoff from the transformer (condenser) the condensate is not more than 50 ppm.
The duration of the cleaning process of the transformer (condenser) - not less than 72 hours. For quality
control of neutralization of the transformer (condenser) is the bay with a clean (fresh or regenerated) with
methylene chloride. After holding the liquid is discharged into the collection of the E6 and analyzed for
PCB.
Fresh methylene chloride comes into production in drums, of which the pressure of compressed nitrogen
peredavlivaetsya in a container from which it is sent to the pump capacity E1 H4.
In the process of neutralizing transformer (condenser) is applied vacuum system using a vacuum pump
H5 in operations:
suction undrainable remainder of the transformer (condenser);
suction of the solvent vapor and purge nitrogen from the transformer (condenser) before disassembly;
preliminary evacuation of the transformer (condenser) and the system before disposing.
Suction gas mixture after the condenser T4 / 1,2 before entering the vacuum pump H5 purified from
impurities in the adsorber K2 with activated charcoal. Between the column K2 and the vacuum pump is
installed H5 vacuum trap E7.
To clean the air circulating through the heat chamber during heating of the transformer (condenser), the
impurities of PCB vapors and air blown through the oven at the transformer cooling (condenser) in the
process of flushing impurities from methylene chloride before release into the atmosphere is set K1
adsorber with activated charcoal. The service activated carbon is determined by its brand name and
sorption capacity. The spent carbon is returned to the installation of thermal decontamination.
Inactivated transformer (condenser) after purging with nitrogen up to the content of methylene chloride in
nitrogen, less than 50 mg/m3 is broken down into its constituent parts. Metal components and building a
FINAL REPORT for Contract No. CS-NPA-Arctic-13/2009 of December 01, 2009 within the framework of pilot project Development of
Technology of clean up of the area of Decommissioned Sites of The Russian Federation Ministry of Defense in the Arctic by the Example of
Alexanra Island of Franz Josef Land Archipelago from Hazardous Waste
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