Mercury Distribution of Major Components from 3-baned and General Spent Fluorescent Lamp

2017

Sustainability

Self Cite

Abstract:In a pilot-plant-scale thermal mercury treatment of phosphor powder from spent fluorescent lamps, energy consumption was estimated to control mercury content by the consideration of reaction kinetics. Mercury content was analyzed as a function of treatment temperature and time. The initial mercury content of the phosphor powder used in the thermal process was approximately 3500 mg/kg. The target mercury content in the phosphor powder thermal process of the phosphor powder was 5 mg/kg or less at 400 • C or higher because the target mercury content was recommended by Minamata Convention and Basel Convention. During thermal processing, the reaction rate was represented by a first order reaction with the Arrhenius equation. The reaction rate constant increased with temperature from 0.0112 min −1 at 350 • C to 0.0558 min −1 at 600 • C. The frequency factor was 2.51 min −1 , and the activation energy was 6509.11 kcal/kg. Reaction rate constants were used to evaluate the treatment time required to reduce mercury content in phosphor powder to be less than 5 mg/kg. The total energy consumption in a pilot-plant-scale thermal process was evaluated to determine the optimal temperature for removing mercury in phosphor powder.

“…Heat loss from heat-up and from maintaining the temperature of the apparatus can be expressed in Equation (10).…”

Section: Theoretical Backgroundmentioning

confidence: 99%

“…Q Loss o f Heat-up and Loss o f Maintaining = Lt (10) where L (kW) is the convection heat loss from the outside air and t (h) is the operation time. L is expressed in Equation (11).…”

Section: Theoretical Backgroundmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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Evaluation of Energy Consumption in the Mercury Treatment of Phosphor Powder from Spent Fluorescent Lamps Using a Thermal Process

Choi

2017

Sustainability

Self Cite

“…The major components of CFL from 3 manufactures (A, B, C) are shown in Table 1 [10]. The total mass of CFL can be varied with lamp manufacture s [11]. Also, mass of the components from CFLs is different from lamp manufactures.…”

Section: Methodsmentioning

confidence: 99%

Evaluation on Recovery of Glass and Plastics from Compact Fluorescent Lamps (CFLs) by Air Separation Unit

Choi

2016

Self Cite

Abstract. Compact Fluorescent Lamps (CFLs) are composed of glass, plastic, non-ferrous metal, ferrous metal, paper, plastic, rubber, and so on. In order to separate glass and plastic among CFLs components, air separation unit is applied using the difference in specific gravity. Since specific gravities of glass, plastic, non-ferrous metals, rubber, etc. were widely spread, it can be separated by the different specific gravity between 0.40 and 4.36. In air separation unit, particle size and air speed are controlled to recover glass and plastics among the components of CFLs. In other words, it can be removed paper and vinyl to recover glass and plastics. The specific gravities of paper and vinyl in CFLs are 0.45 and 0.88, respectively. And the specific gravities of glass and plastics are almost similar to be 2.2-2.6. In air separation unit, the used particle size of the components from CFLs is less than 6 mm. Since phosphor powder and ferrous metals are recovered prior to the air separation unit, the components are not involved those materials. By utilizing a vertical and zigzag type of air separation unit, thereafter, recovery of glass and plastics is estimated with changing air speed. As the air speed increased from 3.08 m/s to 6.75 m/s, separation efficiency of glass and plastics increased from 42.0% to 99.3%. Due to the experimental results of air separation unit, it can find that paper and vinyl from the components of CFLs be efficiently removed by the air separation unit.

Estimation of mercury amount in the components of spent U-type lamp

Environmental Technology

2016

Spent U-type lamps are strongly encouraged to be separately managed in Korea, because U-type lamps are categorized as a household waste and thereby could not be managed properly. Determination of mercury amount in the components of U-type lamp, such as plastics, glass tube and phosphor powder from 3 U-type lamp manufacturers (A, B and C), is carried out to estimate the mercury content in spent U-type lamps. Regardless of lamp manufacturers, the portion of mercury in phosphor powder was higher than 90%, but that in plastics and others was less than 1%. At an air flow rate of 1.0 L/min, the range of the initial mercury concentration in vapor phase for U-type lamp was between 849 and 2076 µg/m from 3 companies. The estimated mercury amount in vapor phase of U-type lamp was in the range from 0.206 mg for company A to 0.593 mg for company B. And the portion of mercury in vapor phase in the total amount of mercury was estimated in the range from 3.0% for company A to 6.7% for company B. Hence, it is desirable to get rid of mercury from phosphor powder in order to perform U-type lamps recycling.