Надежность подземного хранения водорода совместно с метаном в терригенных геологических формациях

The beneficial effect of antibiotics in pouchitis suggests that an unidentified fecal bacterial product causes this condition. A candidate compound is hydrogen sulfide, a highly toxic gas produced by certain fecal bacteria, which causes tissue injury in experimental models. We investigated hydrogen sulfide release and sulfate-reducing bacterial counts in pouch contents to determine whether hydrogen sulfide production correlates with pouchitis. During incubation at 37 degrees C, the production of hydrogen sulfide, methylmercaptan, carbon dioxide, and hydrogen were studied using fresh fecal specimens obtained from 50 patients with ileoanal pouches constructed after total proctocolectomy for ulcerative colitis (n = 45) or for familial adenomatous polyposis (n = 5). Patients with ulcerative colitis were divided into five groups: a) no history of pouchitis (pouch for at least 2 years; n = 8); b) past episode(s) of pouchitis but no active disease for the previous year (n = 9); c) pouchitis in the past year but presently inactive (n = 9); d) ongoing antibiotic treatment (metronidazole or ciprofloxacin) for pouchitis (n = 11); e) currently suffering from pouchitis (n = 8). Release of hydrogen sulfide when pouchitis was active (6.06 +/- 1.03 micromol g(-1) 4 h(-1)) or had occurred in the past year (4.71 +/- 0.41 pmol g(-1) 4 h(-1)) was significantly higher (P < 0.05) than when pouchitis had never occurred (1.71 +/- 0.43 micromol g(-1) 4 h(-1)) or had been inactive in the past year (2.62 +/- 0.49 micromol g(-1) 4 h(-1)). Antibiotic therapy was associated with very low hydrogen sulfide release (0.68 +/- 0.29 micromol g(-1) 4 h(-1)). Pouch contents from familial adenomatous polyposis patients produced significantly less hydrogen sulfide (0.75 +/- 0.09 micromol g(-1) 4 h(-1)) than did any group of nonantibiotic-treated ulcerative colitis patients. Sulfate-reducing bacterial counts in active pouchitis (9.5 +/- 0.5 log10/g) were significantly higher than in those who never experienced pouchitis (7.38 +/- 0.32 log10/g), and these counts fell dramatically with antibiotic treatment. No statistically significant differences in carbon dioxide and hydrogen were observed among the groups not receiving antibiotics. Pouch contents of patients with ongoing pouchitis or an episode within the previous year released significantly more hydrogen sulfide than did the contents of patients who never had an attack of pouchitis and those with longstanding inactive disease. The response to therapy with metronidazole or ciprofloxacin was associated with marked reductions in hydrogen sulfide release and sulfate-reducing bacteria. These results provide a rationale for additional studies to determine whether the high sulfide production is a cause or effect of pouchitis. The lower hydrogen sulfide production by pouch contents of familial adenomatous polyposis vs. patients with ulcerative colitis suggests a fundamental difference in gut sulfide metabolism that could have implications for the etiology of ulcerative colitis as well as the pouchitis of patients with ulcerative colitis.

Vapour pressures of aqueous solutions containing ammonia and carbon dioxide, ammonia and hydrogen sulphide or ammonia, carbon dioxide and hydrogen sulphide, have been determined at temperatures from 20‐60° C. Dissolved hydrogen sulphide is present almost completely in the form of ammonium hydrosulphide. Dissolved carbon dioxide is present in the form of carbonate, bicarbonate and carbamate of ammonium.The experimental vapour pressure data are interpreted from the viewpoint of the ionic equilibria in the solutions. The numerical values of the equilibrium constants have been derived.A method is described enabling one to calculate the vapour pressure for arbitrary compositions of the solutions.Diagrams are given for the vapour pressures of the two‐component system ammonia‐carbon dioxide, as a function of the total ammonia content and the ratio R (= total carbon dioxide/total ammonia). From these diagrams also the vapour pressures of the three‐component system ammonia‐carbon dioxide‐hydrogen sulphide can be derived approximatively.

Compressed natural gas (CNG) is one of the fossil fuels, and is nothing other than the compressed version of the natural gas extracted by mining. CNG is mostly used for heating and the production of electricity. If used as a fuel for motor vehicles, it entails less emission of CO2 than does the use of gasoline or diesel. Irrespective of usage, the contents of commercial natural gas are strictly regulated by laws. Besides energy density, hydrogen sulfide content for example is a critical quality parameter of natural gas, hence it is strictly regulated. Hydrogen sulfide is extremely corrosive for the pipes. When burning such gases, hydrogen sulfide is converted to sulfur dioxide (SO2) which is harmful for the environment. We have devised a procedure for the replacement of solid adsorbents and amine-containing chemicals in hydrogen sulfide removal that can also be used with gases containing carbon dioxide. The essence of the method is that the natural gas is brought into contact with a dilute solution of NaOH in contact time of less than 1 second. At the beginning of chemisorption, hydrogen sulfide is absorbed 1-2 orders of magnitude faster than carbon dioxide. For the experiments, a laboratory Jet reactor was planned. The efficiency of purification was examined with different hydrogen sulfide containing model gas mixtures with respect to the following parameters: gas volume flow, alkali volume flow and alkali concentration.

Corrosion tests were conducted in the laboratory on . steel, stainless steels, Monel, and nickel in amine solution saturated with carbon dioxide and hydrogen sulfide. The effects of temperature, pressure, and amine concentration and the presence of sludge were explored. Types 304 and 316 stainless steel gave consistently low corrosion rates under all conditions. Monel was satisfactory when carbon dioxide or hydrogen sulfide were present singularly in the amine but mixtures of the gases were damaging. Hydrogen sulfide alone in amine solution was not highly corrosive to any of the alloys. Corrosion increased with increase in severity of conditions. Results of a number of field corrosion tests in operating equipment under a variety of conditions of temperature and concentration are given together with an interpretation of the data in the light of practical experience. 8.4.3

This chapter investigates three ionic liquids (ILs), namely butyl pyridinium acetate ([BPy][AC]), butyl pyridinium benzoate ([BPy][BZ]), and butyl pyridinium propionate ([BPy][PR]), applied as potential absorbents for acid gases (hydrogen sulfide and carbon dioxide) in natural gas. The molecular dynamics (MD) simulation results indicate that the ILs have a relatively low dynamic and compact structure, with high viscosity in their pure state. Consistent with the findings of other researchers, the qualitative analysis of the simulation data for the mixture of an IL with acid and methane gases suggests that the dynamics of the IL enhances in the presence of these gases. The radial distribution functions reveal strong interactions and structural compatibility between the ILs and hydrogen sulfide molecules, indicating their suitability for hydrogen sulfide absorption. The amount of carbon dioxide gas absorbed by these ILs was calculated to be in the range of 0.08–0.11, while the absorption of hydrogen sulfide gas ranged from 0.12 to 0.18. [BPy][PR] IL exhibited the highest percentage of absorption for carbon dioxide (0.1083) and hydrogen sulfide (0.177). Furthermore, a comparison of the interactions between acidic gases and [BPy][PR] with the results of methyldiethanolamine (MDEA) clearly demonstrates the superior physical absorption of these gases by [BPy][PR].

A simulation study of reducing carbon dioxide and hydrogen sulfide adsorption in dehydration beds

Chapter 7 - Acid gas treating

This survey has described the foreseeable environmental and economic impacts of enhanced oil-recovery (EOR) on U.S. oil production between 1980 and 2000. It has indicated that EOR production may be expected to rise from the approximately 4% of total U.S. oil production in 1980, to the projected approximations of 10.5% in 1985, 18.5% in 1990, 23% in 1995, and perhaps 30% in 2000. These percentages are substantial, particularly as this form of oil production has been, up until recently, quite limited. Many of the processes are still in the laboratory stage of development—particularly chemical and microbiological processes. With continued laboratory experimentation and field research, it is possible that the percentages could be even greater than the above suggestions as we reach into the 21st Century.The potential for EOR is very considerable and probably great, as it could involve some two-thirds of all the oil already identified in the United States and assumed to be unrecoverable by primary or secondary means. The U.S. Department of Energy (DOE) has given important incentives to the EOR industry to make such increased production worth while through raising prices to compensate for the cost of equipment, and deducting expenditure on such equipment from a new ‘Windfall Profit Tax’.Along with EOR's economic potential, there are two major ecological dangers: air pollution through thermal processes, and ground-water pollution through chemical processes. It is essential to the well-being of the United States that clean air standards be adhered to, and that the equipment necessary to purify the air (particularly in California) be available and operate to reduce emissions.A great deal more research needs to be undertaken towards developing safeguards to ensure that drinkingwater is not contaminated by dangerous chemicals which may be used in ‘chemical flooding’ of depleted oil-wells. Many of these chemicals have merely ‘come out of the laboratory’ and are sold by chemical companies without sufficient field-testing. How far these chemicals could travel underground must still be determined. It is also important to ensure that carbon dioxide, fed into a geological formation, can be recaptured and re-injected without escaping into the atmosphere, where there is the potential danger of a global ‘greenhouse effect’ upon the world's temperature. Finally, it is important to safeguard the Earth against microbes which could be injected into its geological strata without sufficient knowledge of their impact on the ecology of the Earth. Thus, much environmental research will be called for with these new methods of producing oil for Man's use.This study has reviewed the four major methods of EOR that are currently being utilized or proposed— thermal processes, miscible and semi-miscible processes, chemical processes, and microbiological processes, and found that they could all have ongoing possibilities.Given appropriate environmental safeguards, EOR should become a major force in the production of energy for the United States over the next 20 years, and it seems reasonable to expect that much the same could apply to other parts of the world. However, it is important that safeguarding the environment should guide the DOE in terms of its incentive programmes for specific processes.

There is no information on poultry emissions in national reports on anthropogenic gas release and greenhouse gas uptake. Gaseous pollutants are formed as a result of poultry enteric fermentation and fecal decomposition; their concentration depends on the ventilation efficiency and speed, as well as on density of poultry planting. Determination of greenhouse gas emissions amount from industrial poultry farming is an urgent task. The relative greenhouse gases emissions produced by poultry at the poultry house is approximately 0,045 kg in CO2 equivalent. At the same time, there is no information on the greenhouse gases’ concentration quantitative changing at poultry growing process. The aim of the study is greenhouse gases concentration change determining throughout the broiler chickens growing entire process. Studies of gases concentration in developed experimental technological module for broilers’ growing on each level of a two level battery have been carried out. Broiler chickens of the ROSS-308 cross for 6 weeks were raised. Greenhouse gas concentrations at the end of each week were measured. Due to the fact that the necessary temperature and humidity in the module were automatically maintained, only the natural ventilation system worked until the third week of cultivation, as a result the gas concentration inside the module increased, but did not reach the maximum of permissible concentration’s values. With the forced ventilation system’s automatic activation, the gases concentration at this technological module to minimum values was decreased. The gases’ concentration inside the module within the following limits varying: carbon dioxide - from 1029,9 to 4826,5 mg/m3, ammonia - from 2,05 to 23,11 mg/m3, hydrogen sulfide - from 0,12 to 0,96 mg/m3, methane - from 64,6 to 246,1 mg/m3. The gases’ concentration outside the technological module varies within the limits: carbon dioxide - from 366,4 to 1461,6 mg/m3, ammonia - from 0 to 3,42 mg/m3, hydrogen sulfide - from 0 to 0,35 mg/m3, methane - from 65,2 to 263,1 mg/m3.

Influence of Gas Components on the Formation of Carbonyl Sulfide over Water-Gas Shift Catalyst B303Q

The standard industrial process for the purification of natural gas is to remove acid gases, mainly hydrogen sulfide and carbon dioxide, by the absorption and reaction of these gases with alkanolamines, but the lack of reliable and accurate vapor‐liquid equilibrium (VLE) data impedes the commercial application of more efficient alkanolamine systems. The objective of this research was to develop an FTIR apparatus and an in‐situ technique capable of making VLE measurements of acid‐gas–aqueous alkanolamine systems and to improve the accuracy of vapor–liquid equilibrium measurements at low hydrogen sulfide and carbon dioxide concentrations. The new FTIR apparatus and technique were tested in VLE measurements of low concentrations of carbon dioxide and hydrogen sulfide in aqueous mixtures of diethanolamine.

Contaminated gases emissions from livestock industry are becoming one of the most significant contributors to the increasingly serious environmental pollution. To find a way to reduce gases emissions, it is essential to reveal the factors that can affect the gases emissions. In this study, the concentrations of typical gases (including ammonia (NH3), carbon dioxide (CO2), hydrogen sulfide (H2S), and sulfur dioxide (SO2)) generated from naturally-ventilated dairy cow barns were detected through the sample-data method in Tianjin, northern China. Indoor environmental conditions, such as temperature (T) and relative humidity (RH), were measured simultaneously. After applying the carbon dioxide mass balance method, ammonia, hydrogen sulfide and sulfur dioxide emissions were determined. The correlation analysis and regression analysis between the climate condition and gas emissions were conducted to assess the data collected in dairy cow barns during the whole study period. There was a significant relationship between environmental conditions and gas emissions. NH3, H2S and SO2 emissions from the building are in the range of 0.98-2.36 g/LU·h, 0-0.034 g/LU·h, and 0-0.069 g/LU·h, respectively. The numerical analysis shows that the NH3 emission is highly correlated with the temperature and relative humidity. The ventilation rate shows a positive correlation with all the three gases. Keywords: gas emissions, environmental conditions, correlation analysis, regression analysis, carbon dioxide, H2S emission, NH3 emission, SO2 emission DOI: 10.25165/j.ijabe.20201302.4802 Citation: Zou B, Shi Z X, Du S H. Gases emissions estimation and analysis by using carbon dioxide balance method in natural-ventilated dairy cow barns. Int J Agric & Biol Eng, 2020; 13(2): 41–47.

The utility of waters from the high-temperature areas in Iceland for space heating as determined by their chemical composition

The article deals with the causes of formation of ballast salts in circulating solutions of the absorption process during the purification of coke oven gas from hydrogen sulphide. The processes occurring during the hydrogen sulphide recovery from coke oven gas using the vacuum carbonate method, which consists in washing the coke oven gas with a soda solution, are considered in detail. In this process, acidic components are captured: hydrogen sulphide, carbon dioxide and hydrogen cyanide. The article analyses the causes and stages of ballast salt formation, provides equations and conditions for the relevant reactions The article analyses the causes and stages of ballast salt formation, provides equations for the relevant reactions, and indicates ways to reduce their formation. The advantages of a two-stage purification scheme are shown, which allow to reduce the content of unregenerated ballast salts at the second stage. At the same time, the potential of the first stage of purification is used for the selective extraction of hydrogen cyanide (HCN). It has been shown that the selective absorption of hydrogen cyanide in relation to hydrogen sulphide (H2S) at the first stage of purification leads to a significant reduction in the supply of hydrogen cyanide to the second stage of absorption, and, accordingly, to a reduction in the formation of unregenerated ballast salts in the second stage solution. The article calculates the consumption of soda products in the process of vacuum-carbonate desulphurisation with selective absorption of hydrogen cyanide in the first stage scrubber and hydrogen sulphide in the second stage scrubber, and also calculates the soda savings for the production of solutions of different concentrations. The possibility of integrating the used technical solutions into the existing scheme of two-stage desulphurisation is noted. The considered scheme of coke oven gas desulphurisation with isolated solution cycles of different concentrations can be applied in the perspective projects of SE GIPROKOKS for enterprises in Ukraine and abroad. Keywords: ballast salts, two-stage vacuum-carbonate desulphurisation, selective hydrogen cyanide extraction. Corresponding author: M.S. Solovyov, e-mail: solovjov.gpk.ua@gmail.com

Using biogas instead of fossil fuels decreases pollutants such as solid particles, sulphur dioxide, nitrogen oxides concentrations in the environment. Green energy and development of relevant infrastructure improves air quality considerably. Chemical, physical, biological methods are used for biogas purification. The main difficulties using biological methods are selection of suitable microorganisms’ suspensions and making optimal conditions in photobioreactor. Different origin and structure microalgae suspensions are used applying biological treatment methods. Monoraphidium griffithi, which is widespread in fresh water, has relatively high potential. Microalgae’ cultures absorb the main components of biogas – carbon dioxide (CO2) and hydrogen sulphide (H2S). Absorbtion processes are based on photosynthesis. Microalgae absorb specific components of biogas when there are suitable light source and nutrient solvent. The main purposes of the research are to asses emission of biogas using different substrates (chicken manure and wastewater sludge). Also, it was measured main physical and chemical characteristics of both substrates: acidicy, temperature, redox potential, conductivity, biohemical oxygen demand. According results of the research, emission from wastewater sludge is greater than from chicken manure so sludge was chosen in teh next stage of the research. The next stage – asssessment of purification efficienty using Monoraphidium grifftihii suspension. Raw biogas was supplied to photobioreacor (with microalgae suspension). Alterations of methane, carbon dioxide, oxygen, hydrogen sulphide concentrations were measured precisely. According to results concentration of methane in the beginning of the researc was 62%, after 35 days – 69%. Meanwhile carbon dioxide – 37% and 31% by analogy. Experimental research alows to assess Monoraphidium griffithi absorption capacity of ballast components. Results were compared to different scientists’ results which were present in scientific journals and publications. Comparative analysis alows to assess practical possibilities to use Monoraphidium griffithi as biological treatment of raw biogas.