Feasibility study of fluorescent lamp waste recycling by thermal desorption

Abstract

The proposed Minamata Convention ban on the use of fluorescent lamps at the end of 2020, with a consequent reduction in mercury (Hg) light products, is expected to produce large amounts of discarded fluorescent bulbs. In this context, the most effective recycling options are a thermal mercury recovery system and/or aqueous solution leaching (lixiviation) to recover rare earth elements (REEs). Due to the heterogeneous nature of these wastes, a complete characterization of Hg compounds in addition to a determination of their desorption temperatures is required for their recycling. The objective of this study is to assess the feasibility of a fast cost-effective thermal characterization to ameliorate recycling treatments. A pyrolysis heating system with a heat ramping capability combined with atomic absorption spectrometry makes it possible to obtain residue data with regard to the temperature ranges needed to achieve total Hg desorption. The major drawback of these heat treatments has been the amount of Hg absorbed from the residue by the glass matrices, ranging from 23.4 to 39.1% in the samples studied. Meanwhile, it has been estimated that 70% of Hg is recovered at a temperature of 437 °C.

Biogeochemical prospecting of metallic critical raw materials: soil to plant transfer in SW Ciudad Real Province, Spain

“…Analytical determinations of both types of samples (pressed pills of leaves and milled soil) were carried out by means of energy-dispersive X-ray fluorescence (EDXRF) using a Malvern-Panalytical Epsilon One device. Total Hg was analyzed on the milled samples using atomic absorption spectrometry with Zeeman effect and a high-frequency modulation of light (ZAAS-HFM) using a Lumex RA-915 M device with a pyrolytic unit (PYRO-915 +); this procedure involves the pyrolysis of the samples (both soil and vegetal) at 900 °C and their transport by filtered air to the analytical cell (Esbrí et al 2021 ).…”

Evaluation of antimony availability in a mining context: Impact for the environment, and for mineral exploration and exploitation.

“…Total Hg was determined by atomic absorption spectrometry (AAS) with a Lumex RA-915 M device equipped with a Pyro-915+ pyrolysis unit. Samples were pyrolysed at 900 • C according to a gaseous Hg atomisation method, which is drawn by a stream of carrier air at 3 L min − 1 to the analytical cell (Esbrí et al, 2021). The quality control included the analysis of the previously mentioned certified reference material for the soil and leaf samples, with a recovery rate of 99-105% and 92-114%, respectively.…”

Geochemical Assessment of Mineral Resource Potential in a Hg-Sb-Pb-Zn Mining Area: The Almadén and Guadalmez Synclines (South-Central Spain)

“…Larger data dispersions were observed in major elements (SiO 2 , among others), and significant dispersions of some trace elements were observed, especially Pb, As, S, and Zn (>25% relative standard deviation), which represent local anomalies in the geological materials (Precambrian). The determination of total Hg concentrations was carried out by means of atomic absorption spectrometry with the Zeeman effect, using a Lumex RA-915M device (LUMEX Instruments, St. Petersburg, Russia) combined with a PYRO-915 pyrolizer [25]. The total Si concentrations were obtained by means of energy-dispersive X-ray fluorescence (ED-XRF), using an Epsilon1 XRF Spectrometer.…”