The ninth test run of Joule-Heated cylindrical electrode melter on an engineering scale (JCEM-E9); Research report on solidification of high-level liquid waste

; ; *; *; Masaki, Toshio; Kobayashi, Hiroaki; *

PNC TN8410 98-041, 185 Pages, 1998/02

PNC-TN8410-98-041.pdf:7.51MB

The 9 test of Joule-Heated Cylindrical Electrode Melter - Engineering Scale (JCEM-E9 Test) was carried out from June to July 1996, as a part of the development program on an advanced glass melter. The principal purpose of the test was to estimate the effect of noble metal on operation of the melter with simulated high-level liquid waste. Besides, we also evaluated the basic operational characteristics with corrosion of electrodes, qualities of produced glass etc. JCEM-E is an electric glass melter with an internal electrode and an external electrode in a subsidiary furnace. The internal electrode is a rod inserted in the center of external electrode that is a cylindrical tank. The glass is melted by conducting electric current through the molten glass between the internal and external electrodes. The subsidiary furnace is composed of multi-layer refractories inside a metallic casing and is equipped with the resistance heaters. Melting surface area is 0.35 m that i8 approximately half of 0.66 m of TVF melter. In the test, 13 batches of glass was produced and total weight of produced glass was 3663kg. As a result, The maximum processing rate of JCEM-E with simulated HLLW including noble metals was 4.205.60kg/h, and decreased to less than 80 percent compared with JCEM-E8 Test with non-noble metals HLLW. It was considered that the decrease of the rate arose from concentration of current due to non-uniform distribution of noble metals in molten glass. Judging from the balance of feed and draining, and as a consequence of the observation inside the melter after the test, the draining of noble metals from the nozzle was good. As for the quality of glass produced in the test, properties of concern were comparable with those of standard glass of TVF.

Development of simulation model for cold-cap of TVF glass melter

Asahi, Yoshimitsu; Kodaka, Akira

no journal, , 

In the glass production of TVF melter, as raw material, fiberglass frit cartridges saturated with HAW are supplied to the melter. A lot of in-melting cartridges float on the molten glass surface and form a layer called cold-cap. A simulation model of the cold-cap, which enables reproduction of temperature distribution was developed. The cold-cap was modeled as a two-phase flow of cartridges and molten glass with fluid-particle interaction. The increasing of the apparent viscosity and the decreasing of joule heat current and thermal conductivity caused by floating cartridges are defined as a function of the concentration of solid particles. By involving these models simultaneously, a simulation in regard to an operation during glass production for the 2nd melter in TVF yields a slow fluid velocity at the cold-cap region and reproduced a thermally isolated layer, and the change of temperature observed at the bottom side of the cold-cap.