COMPARISON OF THREE OXIDIZING AGENTS FOR EFFICIENCY OF MERCURY REMOVAL IN A PACKED-BED WET SCRUBBER FROM INFECTIOUS WASTE INCINERATOR

Clean Air ◽  
2006 ◽  
Vol 7 (2) ◽  
pp. 175-186
Author(s):  
A. Changsuphan ◽  
S. Kerdsuwan ◽  
V. N. Bashkin
2021 ◽  
Vol 19 (5) ◽  
pp. 348-357
Author(s):  
Wenich Vattanapuripakorn ◽  
◽  
Khomson Khannam ◽  
Sathapon Sonsupap ◽  
Umakorn Tongsantia ◽  
...  

Recently, levels of air pollution caused by exhaust gases from infectious waste combustion have been rising at a startling rate. Pollutant gases such as carbon monoxide (CO) and nitrogen dioxide (NO2) have numerous health implications when unsafe amounts are released into the atmosphere. Thus, Pollution Control Systems (PCS) and Gas Cleaner Systems (GCS) play an important role in industries and the monitoring of incinerators. This research evaluated the GCS of rotary kilns in medical facilities located in the Northeast of Thailand. Data was collected from various sites, analyzed, and examined. Furthermore, Ozone (O3) technology was applied to the rotary kiln allowing for the collection of new information on the pollution treatment systems. O3 technology was installed along with the Wet Scrubber System (WSS) catalyzing the oxidation of O3 and pollutant gases. In addition, a chiller was added to control and stabilize the temperature of the water. After the water temperature was controlled, the concentration of O3 increased resulting in an efficient pollution treatment system. Levels of pollutant gas emission were found to be beneath control standards of both Thailand and those of the U.S. EPA. TSP content was reduced significantly from 22.0 mg/m³ to 3.4 mg/m³ (97%), CO content from 13.6 mg/m³ to 1.7 mg/m³ (96%), and NO₂ content fell from 16.3 (mg/m³) to 2.0 mg/m³ (99%). It is clear that the rotary kiln and Ozone technology should be used together in order to create a new and far more effective method of pollution treatment in small and mid-sized cities of Thailand.


2018 ◽  
Vol 27 (1) ◽  
pp. 85
Author(s):  
José A. Acaro R ◽  
Jeannie L. Quispe E. ◽  
Mali I. Salas D.

Nuestro equipo en esta oportunidad hizo una simulación de una torre de lavado, la cual la aplicamos en el reactor UASB, a manera de escala construimos una torre de lavado compuesta por difusores, una cama de sólidos hecha de material de esponja, un tubo de acrílico y todas las conexiones que conducen el biogás con H2S. Los componentes a eliminar y/o remover fueron los gases que salen del reactor, en especial del H2S (gas odorífero y toxico que a grandes concentraciones pude llevar a la muerte y como resultado de sus reacciones con el ambiente puede causar daños en las estructuras con la cual este en contacto) mediante la oxidación con el oxígeno disuelto que proveen las microalgas presentes en el agua de la laguna terciara utilizada. Esta torre de lavado la montamos en las instalaciones de CITRAR‐UNI con el permiso del operador y vimos el comportamiento que tiene esta torre, mediante los monitoreos de oxígeno disuelto, temperatura, pH y sulfatos que realizamos durante tres semanas de monitoreo. Como resultados obtuvimos que la torre de lavado sí oxidaba y removía la contracción de H2S, ya que cuando pasaba el tiempo se consumía el oxígeno disuelto, además de esto también en el monitoreo de sulfatos pudimos observar un aumento de este parámetro es decir la torre si estaba consumiendo en H2S, y por esta razón también disminuyo el olor fétido que produce este gas. Palabras clave.- Torre de lavado, reactor UASB, remoción de sulfuro de hidrógeno. ABSTRACT The present work reports the simulation of a wet scrubber coupled to an UASB reactor. The scrubber consisted of baffles, packed bed of sponge material, an acrylic tube and all the connections necessary to bring the H2S‐ladden biogas. The purpose of the equipment is to eliminate some of the gases coming out of the reactor, through their oxidation by the dissolved oxygen provided by the microalgae present in the water from the tertiary lagoon. Hydrogen sulfide is a foul‐ smelling and toxic gas which can cause death at high concentrations, and can also cause damage to the structures with which it comes into contact. The scrubber was installed on the site of CITRAR‐UNI and the behavior of the equipment was monitored during three weeks by following the temperature, pH and the concentrations of sulfates and dissolved oxygen. The results have shown that the scrubber was effectively an oxidizing environment which was removing H2S, since the dissolved oxygen was actually consumed gradually. It was also observed that the sulfate concentration was increasing, indicating a consumption of H2S, which was also confirmed by a reduction in the odor of the gas. Keywords.- scrubber, UASB reactor, hydrogen sulfide removal .


Author(s):  
Asifa Farooqi ◽  
Ghufranud Din ◽  
Rameesha Hayat ◽  
Malik Badshah ◽  
Samiullah Khan ◽  
...  

Abstract The environmental release of Mercury is continuously increasing with high degree of mobility, transformation and amplified toxicity. Improving remediation strategies is becoming increasingly important to achieve more stringent environmental safety standards. This study develops a lab-scale reactor for bioremediation of aqueous mercury using a biofilm producing bacterial strain, KBH10 isolated from mercury polluted soil. The strain was found resistant to 80 mg/L of HgCl2 and identified as Bacillus nealsonii via 16S rRNA gene sequence analysis. The strain KBH10 was characterized for optimum growth parameters and its mercury biotransformation potential was validated through mercuric reductase assay. A packed-bed column bioreactor was designed for biofilm-mediated mercury removal from artificially contaminated water and residual mercury was estimated. Strain KBH10 could grow at a range of temperature (20–50 °C) and pH (6.0–9.0) with optimum temperature established at 30 °C and pH 7.0. The optimum mercuric reductase activity (77.8 ± 1.7 U/mg) was reported at 30 °C and was stable at a temperature range of 20–50 °C. The residual mercury analysis of artificially contaminated water indicated 60.6 ± 1.5% reduction in mercury content within 5 h of exposure. This regenerative process of biofilm-mediated mercury removal in a packed-bed column bioreactor can provide new insight of its potential use in mercury bioremediation.


2019 ◽  
Vol 11 (18) ◽  
pp. 4980
Author(s):  
Jan Wajs ◽  
Roksana Bochniak ◽  
Aleksandra Golabek

The paper presents and discusses the issues of medical waste (including hazardous ones) and the problems regarding their proper management in Poland. Inappropriate handling of infectious medical waste directly endangers human health and the environment. Infectious waste must be properly disposed of—in practice, the only method of their disposal available in Poland is a thermal treatment in the incinerators tailored for this purpose. This causes many problems to smaller entities such as the local health centers, but also to the beauty and tattoo salons. As a solution to these problems, the mobile medical waste incinerator was proposed. During designing an incinerator unit, a diverse morphological composition of the medical waste should be taken into account, however, there are no inspection reports available in Poland. Based on a few data concerning the composition of the medical waste, the article presents designing considerations in regard to the incinerator’s chamber dimensions. The calculations were carried out for several variants of the waste morphological composition. The own construction of a mobile medical waste incinerator, which conforms to the regulations in Poland and the European Union, was presented. It should be emphasized that it is a novelty on the Polish market, due to the automatic waste feeder into the combustion chamber, adapted to a mobile unit.


2012 ◽  
Vol 209-211 ◽  
pp. 1549-1552
Author(s):  
Sheng Yu Liu ◽  
Ping Liu ◽  
Li Chao Nengzi ◽  
Wei Qiu ◽  
Cheng Wei Lu

The important step for increasing gaseous elemental mercury (Hg0) removal in wet scrubber systems is altering the chemical form of the Hg0to a water-soluble oxidized species. This work focuses on the removal of elemental mercury from simulated flue gas by aqueous K2S2O8in a bubble reactor. In the system of K2S2O8oxidize Hg0, the reaction velocity of K2S2O8and Hg0is soon. Reached a higher removal rate after 10min. Increase the concentration of K2S2O8can remarkably improve the removal rate of Hg0to 85% With the rise of import mercury concentration has increased mercury removal rate to 89.5%.


TAPPI Journal ◽  
2016 ◽  
Vol 15 (4) ◽  
pp. 265-272 ◽  
Author(s):  
ROHAN BANDEKAR ◽  
JIM FREDERICK ◽  
JAROSLAV STAVIK

This study addresses the challenges a dissolving-grade pulp mill in Canada faced in 2014 in meeting its total reduced sulfur (TRS) gas emission limit. These emissions from the recovery boiler exit are controlled by passing the boiler exit gas through a TRS scrubber system. The mill employs a cyclonic direct contact evaporator to concentrate black liquor to firing solids content. The off-gases from the direct contact evaporator flow to the effluent gas control system that consists of a venturi scrubber, a packed bed scrubber, and a heat recovery unit. Emissions of TRS greater than the regulated limit of 15 ppm were observed for a 4-month period in 2014. The level of emissions measured during this period was significantly higher than about 12 ppm, the expected average value based on historic experience. The problem persisted from mid-June 2014 until the annual mill shutdown in October 2014. The main TRS components detected and the performance of the Teller scrubber in capturing them are examined. Other potential causes for these emissions are identified, including mechanical problems such as broken packing in the TRS packed bed scrubber, broken baffle plates in the scrubber, and cyclone evaporator leaks causing air ingress. Repairs were carried out during the mill shutdown, which eliminated the TRS emissions problem.


2019 ◽  
Vol 5 (1) ◽  
pp. 27-33
Author(s):  
Mostafa Sharqawy ◽  
◽  
Robert Zinni

Sign in / Sign up

Export Citation Format

Share Document