Removal Of Hydrogen Sulfide Research Articles

A review on biogas purification through hydrogen sulphide removal

Biogas has been recognized as a clean and renewable form of energy that is produced from biodegradable organic materials via an anaerobic digestion. In fact, biogas has been well expected to substitute current conventional sources of energy. The main composition of biogas includes methane (CH4) and carbon dioxide (CO2), which is accompanied by different contaminants in varied quantities such as ammonia (NH3), water vapour (H2O), hydrogen sulphide (H2S), methyl siloxanes, nitrogen (N2), oxygen (O2), halogenated volatile organic compounds (VOCs), carbon monoxide (CO) and hydrocarbons. Biogas has been widely utilized as either engine fuel or starting material for chemicals, hydrogen and/or synthesis gas productions. For certain applications, a certain purity degree of biogas is required. Technically, the presence of trace components in biogas has been known to negatively affect engine performance. Therefore, a removal of contaminants, particularly H2S and CO2, is expected to significantly improve biogas quality, thus enhancing its performance in various applications. Besides, the removal is performed to meet standardized gas specifications for its usage as vehicle fuel or being injected into a natural gas grid. In practices, different methods for biogas cleaning and upgrading have been recognized, in which differ in terms of functions, efficiency, and required quality of input gas. This study, therefore, aims at reviewing various H2S removal-based biogas cleaning techniques during and after digestion process.

Performance of Sweet Potato’s Leaf-Derived Activated Carbon for Hydrogen Sulphide Removal from Biogas

In this study, sweet potato leaf activated carbon (SpLAC) was prepared by the chemical activation method using KOH and applied as an adsorbent for H2S removal from biogas. The study focused on the understanding of the effect of carbonization temperature (Tc), varying KOH : C activation ratio, flow rate (FR) of biogas, and mass of SpLAC on sample adsorption capacity. The BET analysis was performed for both fresh and spent activated carbons as well as for carbonized samples, which were not activated; also, the activated carbon was characterized by XRF and CHNS techniques. The results showed that removal efficiency (RE) of the SpLAC increased with increase carbonization temperature from 600 to 800°C and the mass of sorbent from 0.4 g to 1.0 g. The optimal test conditions were determined: 1.0 g of sorbent with a KOH : C ratio of 1 : 1, Tc=800°C, and FR=0.02 m3/h which resulted in a sorption capacity of about 3.7 g S/100 g of the SpLAC. Our findings corroborated that H2S removal was contributed not only by the adsorption process with the pore available but also by the presence of iron in the sample that reacted with H2S. Therefore, upon successful H2S sorption, SpLAC is suggested as a viable adsorbent for H2S removal from biogas.

Development and application of modified lye for treating hydrogen sulphide in coal mine

To improve the absorption efficiency of alkaline liquor treated with hydrogen sulphide in coal mines, a single sodium carbonate lye was taken as the basic raw material to modify the absorption of lye by adding the surfactant sodium dodecyl benzene sulfonate (SDBS) and the oxidant hydrogen peroxide. Respectively, the effects of different concentrations of surfactants and oxidants in sodium carbonate solution on the removal of hydrogen sulphide gas were investigated. The results show that the concentration of sodium carbonate solution is positively correlated with the removal rate of hydrogen sulphide. When the concentration of sodium carbonate solution increases to 2%, the initial removal rate of hydrogen sulphide is close to 100%, however, the problem of secondary dissipation of hydrogen sulphide is more significant after vibration. With the increase of SDBS and hydrogen peroxide concentration, the removal rate of hydrogen sulphide from sodium carbonate solution respectively increases to 93.1% and 86.2%. Finally, through experimental analysis and in situ measurements, the optimal ratio of the modified lye in the hydrogen sulphide treatment of this experiment is as follows: the concentration of sodium carbonate solution is shown to be 2%, the concentration of surfactant is 0.4%, and the concentration of oxidant is 0.6%. On this basis, by comparing the 40,201 working face of Xiaozhuang Coal Mine with the 40,202 working face, it is concluded that the average removal rate of the modified lye is 93.5%, and the treatment effect of removing hydrogen sulphide is significant.

Preparation of modified manganese slag slurry for removal of hydrogen sulphide and phosphine

AbstractYellow phosphorus tail gas is one of the most common industrial waste gases in Yunnan Province. The discharge of H2S and PH3 pollutants has caused serious harm to the environment. In this study, the simultaneous removal of H2S and PH3 by modified manganese slag slurry was investigated. The results showed that the highest simultaneous removal efficiency for H2S and PH3 was achieved after adding CuSO4. In order to investigate the relationship between catalytic activity and metal species, catalysts were characterized by FTIR, XRF, SEM, AAS, IC, and chemical element analysis. AAS and chemical element analysis results showed that the main active components of the catalyst were Mn and Cu ions. The catalyst structure changed over the reaction. The contact between the catalyst and H2S and PH3 was hindered by the metal agglomeration on the surface of catalyst, which resulted in the deactivation of the catalyst.

Sulfolane and di-iso-propanol lean amine blend operating temperature and pressure effect to natural gas sweetening using process simulation

Blending physical and chemical solvents has shown to be promising for removing hydrogen sulfide, carbon dioxide and mercaptan from natural gas effectively. Studies show that using sulfolane and methyl di-ethylene amine blend yields better performance than traditional methods. However, the Shell process depicts that blending sulfolane with di-iso-propanol amine significantly minimizes the problem associated with amine re-circulation efficiency observed with the application of sulfolane and methyl di-ethylene amine. This study aimed at investigating the effect of temperature and pressure to the acid gas removal performance of sulfolane and di-iso-propanol lean solvent using Aspen HYSYS software. In addition, the determination of optimum blend ratio was considered. The acid gas composition of the natural gas stream was 16.9%. This is a hypothetical data used to mimic a relatively high acid gas content in a typical raw natural gas feed. During the process simulation, the lean solvent temperature and pressure were varied between 5 and 210 °C, and 20 and 250 bar, respectively, while maintaining the reactant flow rate at 819.5 kg/h. Findings informs that the optimum blend formulation obtained was 15% water, 15% sulfolane and 70% di-iso-propanol amine at operating temperature and pressure of 50 °C and 45.5 bar, respectively. At the end of the process, the acid gas composition reduced from 16.9 to 0.26%, with an increase in the methane composition by 16.12%. This was as a result of the reduction in the vapor point of the lean solvent, which significantly contributed to enhancing the contact time and efficiency between the gas feed and lean solvent. Hence, the sales gas specification for natural gas was met at lower operating temperature and pressure below 10 °C and 25 bar, respectively.

Alum sludge as an efficient sorbent for hydrogen sulfide removal: Experimental, mechanisms and modeling studies

This paper firstly reported a systematic study of using alum sludge (waterworks residue) for H2S adsorption. Various trials were performed at ambient temperature in a fixed bed column to study the effects of H2S flow rate, sorbent bed depth on the alum sludge adsorption efficiency of H2S. The Breakthrough Curves were simulated by the Thomas model, Bed Depth Service Time model and Yoon-Nelson models. The mechanisms of H2S adsorption onto alum sludge was examined by different physiochemical characterizations of exhausted and raw alum sludge. Moreover, the mass transfer coefficients were determined from mathematical descriptions of breakthrough curves. The alum sludge adsorption capacity was determined to be 374.2 mg of H2S/g, slightly decreasing with the increasing flow rate and increasing with the increasing bed depth. All the three models successfully predict breakthrough curves which could be used for scaling-up purposes. The microporous structure, alkaline pH and the inherent metal species of the alum sludge promoted the formation of metal sulphate species. This study demonstrated that alum sludge could be used as cost-effective, largely available, and efficient sorbent for H2S removal.

Removal of Hydrogen Sulfide from Biogas Using a Red Rock

The potential of red rock (RR) materials for the removal of H2S from biogas was studied. The rock samples were collected, sieved, and organized in various particle size ranges such as 0.32-250 μm, 250-500 μm, 500-750 μm, 750 μm-1 mm, and 1-1.5 mm. These samples were calcinated at the various temperatures as 500°C, 750°C, and 1000°C and then characterized for phase composition by energy-dispersive X-ray florescent technique, surface morphology by Zeiss Ultra Plus Field Emission Scanning Electron Microscopy (FE-SEM), and surface area by the Brunauer-Emmett-Teller (BET) method. The calcinated RR was filled in the bed reactor, and biogas was allowed to pass through the adsorbent while recording the inlet and exit concentration of H2S. The results show that particle size, calcination temperature, adsorbent mass, and biogas flow rate were parameters that influenced the removal efficiency and adsorption capacity of RR. The sample sieved at 0.32-250 μm and calcinated at a temperature of 1000°C showed 95% high removal efficiency and adsorption capacity of 0.37 g/100 g of the sorbent. Regeneration of spent materials when exposed to air, keep on by reuse in the column, appeared to have nearly similar removal efficiency as the original calcined sample. Thus, the overall performance of the material is promising, which is due to the presence of metals such as iron and magnesium, among others. Therefore, proving the successful elimination of contaminant, RR is an available material for biogas purification.

Removal of Hydrogen Sulfide in Septic Tanks for Treating Black Water via an Immobilized Media of Sulfur-Oxidizing Bacteria.

In South Korea, the installation of septic tanks for treating black water (STBW) is regulated even in sewage treatment areas to prevent the black water deposition in combined sewers. STBWs in which black water is anaerobically decomposed generate high concentrations of hydrogen sulfide (H2S). In this study, an immobilized media of sulfur-oxidizing bacteria (SOB) was used to remove the H2S. SOB media was prepared by using activated sludge collected from a wastewater treatment plant. Prior to field application, an appropriate cultivation period and aeration rate for SOB activation were estimated through a laboratory-scale test. The SOB was activated after a 23-day cultivation period and an aeration rate of 0.25 L-water/L-air/min. Moreover, the maximum H2S removal efficiency was observed at a cultivation period of 43 days and an aeration rate of 0.38 L-water/L-air/min. Then, the SOB media was installed on STBWs of various capacities. The H2S removal efficiency was compared between with and without SOB media. The maximum H2S elimination capacity with SOB media was 12.3 g/m3/h, which was approximately three times higher than without SOB media. Furthermore, the energy efficiency and oxidation rate were also three times higher with SOB, demonstrating the applicability of SOB for H2S removal in STBW.

Evaluation of sorbents for high temperature removal of tars, hydrogen sulphide, hydrogen chloride and ammonia from biomass-derived syngas by using Aspen Plus

Biomass gasification is a promising technology to produce secondary fuels or heat and power, offering considerable advantages over fossil fuels. An important aspect in the usage of producer gas is the removal of harmful contaminants from the raw syngas. Thus, the object of this study is the development of a simulation model for a gasifier including gas clean-up, for which a fluidized-bed gasifier for biomass-derived syngas production was considered, based on a quasi-equilibrium approach through Gibbs free energy minimisation, and including an innovative hot gas cleaning, constituted by a combination of catalyst sorbents inside the gasification reactor, catalysts in the freeboard and subsequent sorbent reactors, by using Aspen Plus software. The gas cleaning chain simulates the raw syngas clean-up for several organic and inorganic contaminants, i.e. toluene, benzene, naphthalene, hydrogen sulphide, hydrogen chloride and ammonia. The tar and inorganic contaminants final values achieved are under 1 g/Nm3 and 1 ppm respectively.

Comprehensive experimental study of acid gases removal process by membrane-assisted gas absorption using imidazolium ionic liquids solutions absorbent

For the first time the comprehensive study of a unique hybrid technique – membrane-assisted gas absorption (MAGA) for the acid gases removal was performed. As a case study, the influences of the presence of imidazolium ionic liquids in the methyldiethanolamine (MDEA) absorbent solutions on process separation efficiency were evaluated on the example of separation of two binary methane-based gases mixtures containing impurities of carbon dioxide or hydrogen sulfide. It was shown, that the addition of small amount (5 vol%) of ionic liquids provides the significant increase on the process separation efficiency in a comparison with pure MDEA performance, which was taken as a reference. Also, the proposed technique was compared with a conventional single-stage membrane gas separation method and it was shown, that membrane-assisted gas absorption provides much higher separation efficiency in a whole observed range of processes productivity. The achieved purity of target component (methane) using absorbent solutions containing imidazolium ionic liquids exceeds the pure MDEA results more when 6 vol% and equals to 90.2 vol% in case of CH4/CO2 separation. In case of hydrogen sulfide removal (the initial content in the mixture is 5 vol%) using a sorbent containing an ionic liquid, the methane purity is 99.87 vol%, which exceeds the purity of methane achieved by using pure MDEA by 1.8 vol%. Moreover, as an important part of process study the dynamics of establishing the steady state under a closed-mode operation was studied and the most efficient operational time regions and ultimate separation performance of a process was observed.

Removal of Hydrogen Sulfide by Hydroxyl-Ferric Oxide in a Slurry Reactor at Low Temperature

A novel desulfurization process was developed using hydroxyl-ferric oxide as the adsorbent and slurry bed as the reactor. The H2S removal performance and cycling behaviors of the adsorbent were inv...

Removal of hydrogen sulfide from water-based drilling fluid using titania/carbon nanotubes nano-hybrid: optimization, kinetics, and isotherms

Removal of hydrogen sulfide from water-based drilling fluid using titania/carbon nanotubes nano-hybrid: optimization, kinetics, and isotherms

Removal of hydrogen sulfide from biogas using activated carbon synthesized from different locally available biomass wastes - a case study from Palestine

ABSTRACT The main aim of this study was to remove hydrogen sulfide (H2S) from biogas by adsorption using synthesized activated carbon prepared using locally available biomass. The effect of the type of precursors, impregnation reagent and bed height was studied in continuous reactors. Three types of biomass wastes (almond shells, eucalyptus and coffee grains) were collected, grinded, sieved, pyrolyzed at 500°C and impregnated with chemical reagents such as potassium hydroxide or zinc chloride. Adsorption tests were performed using a fixed bed filter filled with the produced activated carbon. The highest biochar yield of 36% was obtained eucalyptus followed by almond shells (28.5%) and coffee grains (24%), respectively. The highest adsorption capacity and removal efficiency were obtained with eucalyptus followed by almond shells and coffee grains, respectively. For instance, eucalyptus showed an adsorption capacity of ~690 (mg hydrogen sulfide/g adsorbent) followed by almond (230 mg hydrogen sulfide/g adsorbent) and coffee grains (22 mg hydrogen sulfide/g adsorbent). As an impregnation reagent, potassium hydroxide gave the highest adsorption efficiency and capacity than zinc chloride. Furthermore, the breakthrough time with KOH (180 min) was higher than ZnCl2 (70 min). Increasing the bed height during continuous breakthrough tests increased the adsorption capacity and hydrogen sulfide removal efficiency. The results of this study showed that the adsorption efficiency of the synthesized activated carbon and consequently the hydrogen sulfide removal efficiency could be fine-tuned by selecting an appropriate biomass precursor and proper impregnation reagent.

Решение проблемы очистки нефти от сероводорода на объектах НГДУ «Лениногорскнефть»

Решение проблемы очистки нефти от сероводорода на объектах НГДУ «Лениногорскнефть»

Removal of Hydrogen Sulfide from Biogas Using a Bubbling Tank Fed with Aerated Wastewater

ABSTRACT The work develops a simple bubbling tank scrubber that is fed with aerating wastewater for the removal of hydrogen sulfide (H2S) in biogas. A 2,000 L plastic tank, in which fixed liquid levels 0.80 and 1.0 m and volumes of 1.1 and 1.4 m3 was kept, was used for the scrubbing tests. A polyvinyl chloride (PVC) pipe with holes of 1 mm diameter was used to sparge the biogas into the tank liquid. Results indicate that with an influent liquid of pH 7.5–7.7, a flow rate of 23–25 L min–1, influent biogas flow rates of 0.050–0.200 m3 min–1, and a H2S concentration of 907 ± 212 ppm, the pH of the effluent liquid stabilized at 6.6–6.9. With gas/liquid rate ratio of 2–8 m3 m–3 liquid and volumetric gassing intensities of 0.04–0.20 m3 m–3 liquid min–1, average H2S removals of 86–71% were obtained. Absorption of CO2 in the tested digester gas into the scrubbing liquid caused a decrease in the pH, thus decreasing the H2S removal efficiency. Increasing pH of the scrubbing liquid to 8.0 improved the H2S removal efficiency to as high as 99%.

A microbial fuel cell integrated with an absorption column for the removal of hydrogen sulfide from anaerobic wastewater treatment

A microbial fuel cell integrated with an absorption column for the removal of hydrogen sulfide from anaerobic wastewater treatment

Hydrogen Sulfide Removal of Biogas from Sewage Treatment Plant with Micro-bubble Generation System

Hydrogen Sulfide Removal of Biogas from Sewage Treatment Plant with Micro-bubble Generation System

Simultaneous capture of NH3 and H2S using TiO2 and ZnO nanoparticles - laboratory evaluation and application in a livestock facility

Simultaneous removal of ammonia (NH3) and hydrogen sulphide (H2S) from pre-mixed gases and stored swine manure gases were investigated in laboratory and semi-pilot scale systems and in a swine production facility, using TiO2 and ZnO nanoparticles. Increase of NH3 concentration in the mixture from 50 to 500 ppmv led to higher breakthrough and equilibrium adsorption capacities, while increase of temperature had an opposite effect. Equilibrium adsorption capacities at 22 °C were in the range 6.92–11.95 mg NH3 g−1 and 1.35–3.57 mg NH3 g−1 at 280 °C. Increase of H2S concentration up to a certain level led to higher equilibrium adsorption capacities but no dependency between breakthrough adsorption capacity and H2S concentration was observed. Both breakthrough and equilibrium adsorption capacities increased with the increase of temperature. The highest equilibrium adsorption capacity of 52.31 mg H2S g−1 was obtained with 550 ppmv H2S in the mixture at 140 °C, while the lowest value was 14.55 mg H2S g−1 with 50 ppmv H2S at 22 °C. At low temperature (22 °C) NH3 adsorption occurred through both physical adsorption and chemisorption, while at 280 °C chemisorption was the dominant mechanism. A sulfidation reaction involving ZnO and H2S that was favored by higher temperatures was evident. Treating gases emitted from stored swine manure in a semi-pilot scale adsorption system led to complete elimination of NH3 and H2S. Application of a nano-based air filtration-circulation system with ZnO and TiO2 nanoparticles in a swine production room during manure handling led to removal efficiencies of 67–100% for H2S and 50–100% for NH3.

Development of a molasses wastewater treatment system equipped with a biological desulfurization process.

In this study, a laboratory scale experiment for the treatment of synthetic molasses wastewater using a combination of an anaerobic baffled reactor (ABR) and a two-stage down-flow hanging sponge (TSDHS) reactor (ABR-TSDHS system) was conducted. The TSDHS comprised a closed-type first-stage down-flow hanging sponge (first DHS) for desulfurization and an open-type second-stage DHS (second DHS) for post-treatment of effluent from the ABR and first DHS. Effluent from the second DHS was sprinkled on top of the first DHS, whereas biogas produced from the ABR was supplied to its bottom. A chemical oxygen demand (COD) removal efficiency of 88.3% was found for the ABR-TSDHS system during the final treatment phase. The ABR achieved a maximum organic loading rate (OLR) of 3.70 kg COD/(m3 day). Most of the organic matter was degraded in the first compartment of the ABR, with methane-producing archaea as its main consumer. The biogas generated by the ABR contained high concentrations of hydrogen sulfide (up to 4,500 ppm). In the TSDHS, the first DHS achieved 87.3% hydrogen sulfide removal via dissolution into sprinkled effluent water. Dissolved sulfide in the first DHS effluent was oxidized to sulfate in the second DHS in the absence of aeration. In addition, 85.0% of the ammonia and 57.7% of the total nitrogen were removed in the second DHS via biological reactions, including sulfur-based autotrophic denitrification. Therefore, the ABR-TSDHS system can be applied to not only molasses wastewater treatment but also the desulfurization of the produced biogas.

Removal of Hydrogen Sulfide with Metal Oxides in Packed Bed Reactors—A Review from a Modeling Perspective with Practical Implications

Sulfur, and in particular, H 2 S removal is of significant importance in gas cleaning processes in different applications, including biogas production and biomass gasification. H 2 S removal with metal oxides is one of the most viable alternatives to achieve deep desulfurization. This process is usually conducted in a packed bed configuration in order to provide a high solid surface area in contact with the gas stream per unit of volume. The operating temperature of the process could be as low as room temperature, which is the case in biogas production plants or as high as 900 ∘ C suitable for gasification processes. Depending on the operating temperature and the cleaning requirement, different metal oxides can be used including oxides of Ca, Fe, Cu, Mn and Zn. In this review, the criteria for the design and scale-up of a packed bed units are reviewed and simple relations allowing for quick assessment of process designs and experimental data are presented. Furthermore, modeling methods for the numerical simulation of a packed bed adsorber are discussed.