Gas Washing Research Articles

Influence of Gas Washing and Oil Mixing on the Phase Behavior and Physical Properties of Cambrian Light Oils in the Tazhong Uplift, Tarim Basin

Gas washing and oil mixing have been widely studied in the Tazhong area of the Tarim Basin, but their effects on Cambrian subsaltic dolomite reservoirs have not yet been adequately explored. In this study, the influence of gas washing and oil mixing on light oils from these reservoirs was investigated. Using n-alkane mass depletion (Q value) analysis, light oils from wells ZS1 and ZS5 were analyzed to quantify the intensity of gas washing and to identify possible oil mixing in the Cambrian Awataga (Є2a) and Wusongar (Є1w) reservoirs. Unaltered light oil was recovered and models of phase behavior were constructed by PVT simulation and basin modeling to compare with altered light oils. The results show that the light oil in well ZS1 experienced medium-strength gas washing (Q value = 40.88%), while the gas washing in well ZS5 was weaker (Q value < 40.88%), providing evidence of oil mixing. Despite these changes, the light oils in the Cambrian reservoirs maintained a single liquid-phase state over geologic time without transitioning to condensate or gas phases. These results improve the understanding of gas washing in the Tazhong area and show that it has significantly altered the Cambrian reservoirs and affected the preservation of hydrocarbons after oil accumulation.

TECHNOLOGIES FOR WASTEWATER TREATMENT FROM ARSENIC

The current recycling water supply of metallurgical enterprises does not completely eliminate the discharge of wastewater into environmental water bodies, where the maximum permissible concentration (MPC) of arsenic is 0.05 mg/dm3. Arsenic accumulates in large quantities in washing solutions for cleaning exhaust gases sent to produce sulfuric acid. In this case, a closed gas washing system is used, aimed at concentrating the washing water with arsenic to 10 g/dm3 and sulfuric acid to 40 g/dm3 in order to reduce the volume of wastewater discharge. Another source of arsenic contamination of the hydrosphere is the waters of tailings from enrichment plants, due to the possible oxidation of arsenopyrite and the formation of a soluble form of arsenic compounds.
 A number of methods for arsenic precipitation have been developed: pyrolusite, lime in the form of calcium arsenate; ions of ferric iron and other metals; adsorption by iron (III) hydroxide, aluminum hydroxide, carbon, etc.; sludge flotation; metal sulfides, sorption and extraction. The main criterion for the operation of purifying a solution from arsenic is the possibility of recycling the resulting sediment or the formation of its compounds with minimal solubility in aqueous solutions, allowing its burial in burial grounds.

Prospect and application of flue gas washing liquid from wet scrubber unit at Masaro plastic refinery for organic pesticides

Masaro plastic refinery represents an advanced technology designed to effectively manage residual waste. This innovative approach integrates the principles of incineration and pyrolysis to obtain valuable products, including fuel and flue gas washing liquid from a wet scrubber unit. The flue gas washing liquid contains ammonia, nitrates, nitrites, and phenol compounds which still do not meet the quality standards stipulated by the Ministry of Environment and Forestry. Those compounds should be reclaimed due to their toxicity towards aquatic organisms. Fortunately, they are extensively employed in the agricultural domain such as raw material for fertilizers and pesticides. This research endeavors to conduct a comprehensive analysis of the composition of the flue gas washing liquid. The objective is to evaluate the potential application of its components as main ingredients in pesticide formulations. To augment its effectiveness, supplementary active ingredients are incorporated, derived from various plant species recognized for their efficacy in combatting pests and insects. The extraction process combines flue gas washing liquid with selected plants, such as bintaro fruit, garlic, lemongrass, neem leaves, and tobacco. From the results, this research not only addresses the environmental issue but also provides a sustainable solution to meet the agricultural sector’s demand for sustainable pesticides.

Pyrolysis/combustion potential and heavy metal risk of oily sludge and derived products in industrial scale

Pyrolysis of oily sludge (OS) has been widely applied for harmless disposal in industrial scale with the benefits of high removal and recovery efficiency of total petroleum hydrocarbons (TPHs). However, seldom research focuses on the evaluation of solid products from industrial apparatus. This paper devoted to evaluate the TPHs removal effect and optimizing directions of this technique by assessing the pyrolysis/combustion potential and environmental risk of OS and derived products, including fly ash (FA) and pyrolysis residue (PR). Unexpectedly, FA and PR still carried trace TPHs, ca. 0.27 and 0.24 wt%, which should arise attention. In comparison, the maximum weight losses of combustion for these solid samples were all higher than that of pyrolysis at the same final temperature, ca. 600 °C. Oxygen-rich atmosphere promoted decomposition of deposited coke and degradation of TPHs, especially heavy fractions. Therefore, these products had a certain potential for combustion utilization. Although the total weight losses of FA and PR were similar with that of OS, the comprehensive combustion characteristic index and combustion stability index of OS were much higher than those of FA and PR, indicating TPHs were more inclined to be burned that coke and dissociated metal compounds. Higher heating rate caused an increasing trend of these indexes. The thermal decomposition kinetics study based on the most probable mechanism function showed that FA and PR followed the mechanism of random nucleation and subsequent nucleation growth. The wastewater produced during gas washing was measured that contained large amounts of organics and harmful elements, which should be properly treated before emitted. Heavy metals are the dominant sources of environmental risks of solid products. Pb and Cu in FA and PR showed higher leaching concentrations and posed severer environmental risk than those in OS, which originated from accumulation effect. However, Cr, Ni, and Zn became more stable and safer after thermal pyrolysis/desorption treatment. These information on solid products and wastewater from industrial OS pyrolysis reminds future work to concern on the final disposal of the output of the whole technique.

Geochemical characteristics and gas-washing accumulation mechanism of hydrocarbon from the Xihu Sag, East China Sea Basin

For many petroleum production plays with large amounts of natural gas produced, their hydrocarbon accumulation processes have been reported to be commonly involved with gas-washing. The gas generation intensity of the Xihu Sag, East China Sea Basin is up to 6 × 106 t/km2, which is the primary driving force for gas-washing to occur. 18 oils and 20 gas samples produced from the Eocene – Oligocene sandstone reservoirs in the Xihu Sag has been geochemically characterized to delineate the controlling factor of the gas-washing and in turn better understand the hydrocarbon accumulation mechanism of the study area. The results show that the natural gas is primarily mature-highly mature coal-type gas based on their carbon isotope characteristics. The oils are believed to belong to a same oil family with a similar thermal maturity and have been gas-washed based on either their molecular fingerprints or other geochemical characteristics. The high toluene/n-heptane ratio (Tol/nC7) and high n-alkane mass depletion (Q) of the oils further indicate the occurrence of gas washing. A good correlation between either the reservoir depth or the gas generation intensity of the source kitchen and the n-alkane mass depletion of the crude oil indicate reservoir depth and gas generation intensity are the two primary controlling factors on the gas washing of the study area. In order to further delineate the effects of evaporative fractionation or migration fractionation on the hydrocarbon reservoir, we introduced a new cross plot of n-alkanes mass depletion (Q) versus adamantane/diamantine (A/D) to type the oils related to the gas washing in the study area. The meaning of this paper for the exploration of oil and gas resources will be related to the understanding of different gas washing mechanism, so as to further enhance the exploration efficiency.

Major period and process of hydrocarbon accumulation of deep reservoirs — A case study of Tuoputai area in Tarim Basin, China

Deep hydrocarbon reservoirs in China's Tarim Basin are characterized by multistage accumulation, but the major period and the process of hydrocarbon accumulation are still ambiguous. By integrating analyses of fluid inclusions, light hydrocarbon and diamondoid, and reservoir bitumen, we determined the contribution of oils charged in different periods and reconstructed the hydrocarbon accumulation process of Ordovician reservoirs in the Tuoputai area, which is significant to expand deep petroleum exploration in Tarim Basin. The results show that the abundance of yellow to yellowish-green (34.6%–42.1%) and bluish-green oil inclusions (42.1%–46.2%) is relatively high, followed by the blue oil inclusions (15.4%–23.1%). The Th values of the corresponding coexisting aqueous inclusions are mainly in 70–80 °C, 90–100 °C, and 120–130 °C, respectively. The hydrocarbon charging is mainly in the late Caledonian and the late Hercynian, followed by the Himalayan. However, oils charged in the late Caledonian experienced strong biodegradation with the tectonic uplift in the early Hercynian and were transformed into heavy oils and carbonaceous bitumen. The recharged oils have not been altered by biodegradation, thermal cracking, gas washing, and thermochemical sulfate reduction, the amount of oils charged in the Himalayan was relatively small. And the calculated maturity of oils, determined by vitrinite reflectance (Rc = 1.3%–1.5%), is similar to the thermal evolution degree of the Є1y source rock in late Hercynian (1.3%–1.6%) and far less than that in Himalayan (1.8%–2.0%). Large amounts of oils accumulated in the late Hercynian made a major contribution to the current reservoirs. Deep hydrocarbon reservoirs in Tuoputai area were mainly got accumulated when the formation was shallowly buried and then preserved with the deep burial.

Hydrocarbon migration and accumulation in the large Samandepe Gas Field in the chardzhou step-fault zone, Amu Darya Basin, northeastern Turkmenistan: A response to the tectonic evolution of the northern margin of the tethys

The mechanism of large-scale hydrocarbon accumulation in the Tethys domain has long been of interest to petroleum geologists. Located in the northern margin of the Tethys, the Amu Darya Basin (ADB) is well known for its large, indeed giant, gas fields. However, there has been surprisingly little research on the mechanisms of hydrocarbon accumulation in the basin. This paper investigates the accumulation history of the Samandepe Gas Field, a large condensate gas field in the Chardzhou step-fault zone in the northeastern ADB. Trap evolution in the basin is analyzed, the oil and gas sources and hydrocarbon charging periods are determined, and the process of hydrocarbon migration and accumulation explored to establish the relationship between hydrocarbon accumulation and the tectonic evolution of the Tethys. Geophysical logging, organic geochemistry, fluid inclusion analysis, basin modeling are used for analysis. The results show that hydrocarbon accumulation in the Samandepe Gas Field occurred in two stages. First, a lithological ‘large trap’ formed in a barrier reef belt in the Late Cretaceous Santonian, before the present anticline structure of the gas field formed. This trap was filled with oil generated in Upper Jurassic marine source rocks, forming a lithological paleo-oil reservoir. In the second stage, at the end of the Paleogene, the large trap was reformed as structural traps with reef-shoal reservoirs. Natural gas generated from coal-measure source rocks in Middle and Lower Jurassic strata migrated along basement faults, filling the traps. Excess natural gas displaced the oil, some of which dissolved in the gas, forming ‘gas washing’-type secondary condensate oil and creating a structural condensate oil-bearing field. The inherited paleo-uplift in the step-fault zone is crucial to large-scale hydrocarbon accumulation in the ADB.

Ventilation Study of the Human Lungs by 19F MRI at 0.5 Tesla

To show the feasibility of functional lung assessment by 19F MRI using low field (0.5 T) MRI scanner. One healthy volunteer participated in the studies. As a contrast for 19F pulmonary MRI, the gas mixture of 70% octafluorocyclobutane (OFCB) and 30% oxygen was used. 19F MR images of human lungs were obtained using 2D and 3D FSE methods. MRI data were used for volume reconstruction and for calculation of wash-in/-out and single-breath dynamics measurements. 19F 3D imaging provided information about gas distribution and lung volume assessment. The measured volume of the left and right parts of lungs were ≈1.7L and ≈1.8L, respectively. The wash-in/-out dynamics measurements determined that the effective time of gas washing in was 30 ± 5 s and washing out was 19 ± 4 s. Fractional ventilation was 29 ± 3% and 18 ± 2% for wash-in and wash-out processes, respectively. Dynamics of gas distribution during one breath cycle was analyzed. The calculated inspiration and expiration maps gave normalized effective times [rel. un.] for these stages- 0.95 ± 0.18 and 0.84 ± 0.15, respectively. Different 19F pulmonary MRI methods were implemented: 3D imaging, wash-in/-out dynamics and single respiratory cycle imaging. The results are agreed with known data and demonstrates possibility of ventilation assessment of the lungs at 0.5 Tesla.

Molecular evidence reveals the presence of hydrothermal effect on ultra-deep-preserved organic compounds

Hydrothermal alteration, transformation and synthesis of organic compounds have long been noted in submarine hydrothermal vents, terrestrial hot springs, epithermal deposits and laboratories. However, little is documented about the influence of deep hydrothermal activities on organic compounds at the ultra-deep horizon. It remains unclear to what extent the compounds are hydrothermally (secondarily) affected. Here we report molecular and isotopic level analyses of liquid oils derived from an ultra-deep reservoir in the Tarim Craton, south of the Central Asian Orogenic Belt. The organic compounds had an unexpectedly convoluted molecular and isotopic geochemistry, suggesting that the deep hydrothermal activities impact the organic compounds to varying degrees. In the absence of severe gas washing, in-reservoir mixing and thermochemical sulfate reduction, hydrothermal alteration results in a progressive increase in the relative abundance of organosulfur compounds. The transformation of three compound classes (e.g., phenanthrene ring systems, biphenyl ring systems and dibenzothiophene ring systems) during hydrothermal alteration was observed. As the extent of the hydrothermal effect increases, dibenzothiophene ring systems are favourably formed through the oxidation of phenanthrene ring systems, followed by the incorporation of sulfur from biphenyl ring systems that were less thermally stable. The spatial variation in the hydrothermal effect was decoupled from other thermogenic effects. A new perspective regarding the hydrothermal effect on molecular and isotopic compositions may shed light on the organic–inorganic interactions of deep-sourced organic fluids with their aqueous and mineralogical environments, and the temporal and spatial variation in organic signals and environments at known hydrothermal systems on Earth, Mars and even Titan.

Synthesis of Ni/Y2O3 Nanocomposite through USP and Lyophilisation for Possible Use as Coating.

The Ni/Y2O3 catalyst showed high catalytic activity. Based on this, the aim of this study was to create Ni/Y2O3 nanocomposites powder with two innovative technologies, Ultrasonic Spray Pyrolysis (USP) and lyophilisation. In the USP process, thermal decomposition of the generated aerosols in an N2/H2 reduction atmosphere caused a complete decomposition of the nickel (II) nitrate to elemental Ni, which became trapped on the formed Y2O3 nanoparticles. The Ni/Y2O3 nanocomposite particles were captured via gas washing in an aqueous solution of polyvinylpyrrolidone (PVP) in collection bottles. PVP was chosen for its ability to stabilise nano-suspensions and as an effective cryoprotectant. Consequently, there was no loss or agglomeration of Ni/Y2O3 nanocomposite material during the lyophilisation process. The Ni/Y2O3 nanocomposite powder was analysed using ICP-MS, SEM-EDX, and XPS, which showed the impact of different precursor concentrations on the final Ni/Y2O3 nanocomposite particle composition. In a final step, highly concentrated Ni/Y2O3 nanocomposite ink (Ni/Y2O3 > 0.140 g/mL) and test coatings from this ink were prepared by applying them on a white matte photo paper sheet. The reflection curve of the prepared Ni/Y2O3 nanocomposite coating showed a local maximum at 440 nm with a value of 39% reflection. Given that Ni is located on the surface of the Ni/Y2O3 nanocomposite in the elemental state and according to the identified properties, tests of the catalytic properties of this coating will be performed in the future.

Tracing energy-water-greenhouse gas nexus in national supply chains: China 2017

The nexus of energy, water and greenhouse gas plays a vital role in resource management and response to climate change for all nations. Actions in China is decisive. In this study, the environmentally-extended input-output model and structural path analysis are combined to analyze the energy-water-greenhouse gas nexus for China 2017. The sectors of Mining and washing of coal, Production and distribution of water, Mining and washing of coal are revealed to show the highest embodied energy consumption intensity, embodied water consumption intensity, and embodied greenhouse gas emission intensity, respectively. Among all 149 sectors, some sectors are identified to be more sensitive than others: Farming, Production and supply of electricity and steam are more energy-water-greenhouse gas sensitive, and Mining and washing of coal, Extraction of crude petroleum and natural gas are more energy-greenhouse gas sensitive, and Animal husbandry, Manufacture of pharmaceutical products are more water-greenhouse gas sensitive. Structural path analysis shows that the top 30 supply chain paths contribute to 34.99% of energy consumption, to 39.18% of water consumption, and to 40.18% of greenhouse gas emissions. By studying the main paths, critical sectors of the energy-water-greenhouse gas nexus are further identified as Farming, Mining and washing of coal, Extraction of crude petroleum and natural gas, Production and supply of electricity and steam, Construction of buildings, Civil engineering. Exploring the energy-water-greenhouse gas nexus of 149 sectors could help to lock the key nodes of China's resource management and greenhouse gas emission control in the supply chains.

Experimental Investigation of SO2 Removal from Flue Gases by Cleaning with Solution of Lime Suspension and Formic Acid

The experimental investigation presented in this research was performed in order to examine the possibility of the removal of SO2 from flue gases by cleaning with a solution of lime suspension and formic acid (Ca(OH)2 and HCOOH). Research was conducted in a laboratory plant (rotary kiln) of 44 kW. The mass of the lime suspension (LS) was 400 g. The mass of the LS was homogenized (mixed) in a sample cup with 2 g (0.5%), 4 g (1%) and 8 g (2%) of 60% formic acid. The solution was placed in a gas washing bottle, where a partial flow of flue gas generated by the combustion of diesel fuel was injected. Simultaneously with the diesel fuel combustion, SO2 from a bottle was injected in a rotary kiln. The average mass concentration of SO2 in the flue gas at the entry point of the gas washing bottle was around 2900 ppm. The results indicated that the absorption of SO2 by the cleaning of flue gas with LS was 96.83%. Adding formic acid to the LS in mass ratios of 0.5% (2 g), 1% (4 g) and 2% (8 g) resulted in absorptions of 99.25%, 98.77% and 98%, respectively. The absorption of flue gases in the gas washing bottle with LS, with the addition of formic acid in the mentioned ratios, showed a reduction in sulfates and pH value, and a rise in sulfides and calcium, respectively.

Evolution of a deeply-buried oil reservoir in the north Shuntuoguole Low Uplift, Tarim Basin, western China: Insights from molecular geochemistry and Re–Os geochronology

The recently discovered Shunbei Oilfield is perceived as a remarkable breakthrough in deep marine carbonate petroleum exploration in the Tarim Basin, western China. Constraining the absolute timing of petroleum system evolution is crucial for further hydrocarbon exploration and development in the area. Here, we integrated molecular geochemical correlation, stable carbon isotopes of bulk oil (bitumen) and Re–Os geochronology to trace the petroleum sources, to constrain the absolute timing of hydrocarbon generation, and to reconstruct the petroleum system evolution of the deeply-buried oil accumulations in carbonate reservoirs. Biomarker parameters derived from isoprenoids, terpanes, steranes and aromatic compounds, as well as stable carbon isotopic compositions, revealed that the Ordovician reservoir oils and bitumens were all originated from the same source rock, deposited under a highly-reduced environment with organic matters being predominantly contributed by algae and bacteria. The calculated equivalent vitrinite reflectance (Rc) values of reservoir bitumen and oil samples indicate that the Shunbei Oilfield has experienced at least two hydrocarbon charges. Geochemical characteristics and thermal maturity suggest that the bitumen within the Ordovician Yijianfang Formation reservoirs in the north Shuntuoguole Low Uplift is not originated from thermal cracking, thermochemical sulfate reduction, biodegradation, nor gas washing. Re–Os isotopic data from six reservoir bitumen samples yield an isochron age of 399 ± 12 Ma with an initial 187Os/188Os ratio (Osi) of 1.26 ± 0.11. This age is interpreted to represent the timing of oil generation when compared with the thermal evolution of possible source rocks and other radiometric dating results in the region. A comparison of 187Os/188Os of the 399 Ma-old bitumen and that of possible source rocks at the time of oil generation suggests that the reservoir oil was possibly originated from the lower Cambrian Yuertusi source rock. This work highlights that Re–Os geochronology combining with the initial 187Os/188Os ratio can be used to effectively constrain the timing of hydrocarbon generation in petroleum systems with complex tectonic history, multiple oil charges and alterations.

Roles of coal gasification wastewater in coal electrolysis for hydrogen production

Coal-assisted water electrolysis can reduce the electricity consumption of traditional water electrolysis by 40–60%, but the rate of hydrogen production in this process is very slow. Some coal gasification wastewater can promote the electrical oxidation of coal, the addition of which can achieve resource utilization of wastewater while producing hydrogen at low cost. In this study, the electrolysis characteristics and oxidation mechanism of gas washing water are studied using anode reaction kinetics, and its role in the process of coal electrolysis is studied. The results show that the main anodic reactions of gas washing water are, in order of increasing voltage, the oxidation of organic matter, bromide ions, and the water decomposition reaction, and that there is no obvious interaction between these three oxidation stages and Fe3+/Fe2+. On the one hand, gas washing water can promote the catalysis of iron ions and increase the effective iron concentration in the solution. On the other hand, it plays an important role in changing the surface state of coal particles and improving the electrochemical activity of coal, thereby increasing the reaction rate of coal electrolysis.

Comparison of particulate matter emission and soluble matter collected from combustion cigarettes and heated tobacco products using a setup designed to simulate puffing regimes

An experimental setup was designed and optimized to collect particulate matter suspended in cigarettes smoke or in the aerosol generated during the use of heated tobacco products (HTPs). The setup is mainly based on a gas washing flask containing water where particulate matter and soluble compounds can be trapped, resembling interaction in the body. This system allows to perform puffing experiments in conditions similar to those of the Health Canada Intense puffing regime. In the study, cigarettes and Heets (in IQOS heater) from Philip Morris Products were used. Complementary characterization of this particulate matter has been extracted from experiments on a gas washing flask containing isopropanol. Total organic carbon analysis, laser diffraction, UV-vis spectrophotometry and transmission electron microscopy measurements have shown that cigarette smoke contains a large number and content of compounds soluble in water and isopropanol, together with solid particles generated during combustion. In contrast, negligible presence of non-combustion related particles was detected in Heets aerosol samples. These facts, together with the higher amount of water soluble compounds and higher number of polyaromatic hydrocarbons detected in the cigarettes smoke, allow to conclude that HTPs are less harmful than combusted cigarettes.

Design, construction, and testing of an accurate low-cost humidistat for laboratory-scale applications

Stable and precise control of humidity is imperative for a wide variety of experiments. However, commercially available humidistats (devices that maintain a constant humidity) are often prohibitively expensive. Here, we present a simple yet effective humidistat for laboratory-scale applications that can be easily and affordably (<€250) constructed based on an Arduino Uno as microcontroller, a set of proportional miniature solenoid valves, a gas washing bottle, and a humidity sensor. The microcontroller implements a PID controller that regulates the ratio of a dry and humid airflow. The design and implementation of the device, including a custom driver circuit for the solenoids, are described in detail, and the firmware is freely available online. Finally, we demonstrate its proper operation and performance through step response and long-term stability tests, which shows settling times of approx. 30 s and an attainable relative humidity range of 10–95%

Removal of pollutants from aqueous solutions by coals and residual cokes obtained from simulated underground coal gasification experiments

Groundwater pollution caused by underground coal gasification (UCG) as well as its remediation has attracted significant public attention. In this paper, model gasification experiments on three types of coals with different coalification degrees were carried out using a UCG model test system. The residual coal and coke samples were characterized via SEM, low temperature N2 adsorption, and FT-IR. Thereafter, their adsorption of phenol and Cr(VI) from simulated wastewater as well as the purification of gas washing water were investigated. Compared with the raw coals, the UCG residual cokes presented a higher specific surface area (SBET) of 44.99–381.51 m2/g and total pore volume (Vt) of 0.040–0.228 cm3/g; Cokes obtained from brown coal gasification had the highest SBET and Vt values. Parts of O-containing groups were preserved after the gasification. Phenol and Cr(VI) were removed by all types of coals and residual cokes. The removal rate of phenol increased with SBET and Vt, and cokes presented higher phenol adsorption capacities than those of raw coals. The O-containing groups significantly influenced and favored the removal of Cr(VI). Brown coal and its UCG coke had the highest adsorption capacities, with phenol removal rates of 17.71% and 72.44%, and presented the highest adsorption capacities, with Cr(VI) removal rates of 29.02% and 21.77%, respectively. When UCG residual cokes were used, the removal rates of total organic carbon (TOC) in both types of gas washing water exceeded 82%. Almost all the Cr and Se and some of the Ni were removed from gas washing water.

Otimização do uso de recursos hídricos em uma usina de produção de etanol

O estudo objetivou avaliar, em um processo industrial de uma usina para a produção de etanol a partir de cana-de-açúcar, alternativas possíveis para a otimização do uso dos recursos hídricos com consequente economia na redução da captação de água sem prejuízo à qualidade do produto, à eficiência do processo de conversão e ao equilíbrio financeiro do processo produtivo. Para tanto, foram analisadas as correntes por meio de balanço hídrico e observadas as perdas de água e energia nos sistemas de captação de água; de vapor/condensado; de coleta e tratamento de águas residuárias; de destilação; de refrigeração; de fermentação; de embebição da cana, de lavagem de gases e recuperação de fuligem. Os resultados indicaram que é possível alcançar uma economia de água de 222,1 m³/h contra um consumo atual avaliado de 579,0 m³/h, representando 38,4% de redução no consumo de água, bem como atingir o consumo de 1,0 m³/ton de cana processada conforme ao limite determinado pelo órgão ambiental paulista. Os ganhos na melhoria dos processos de produção têm potencial para produzir um superávit anual de cerca de nove milhões de reais.

Non-catalytic NOx reduction for marine Diesel engine: an experimental approach

Recent legislation concerning air pollutant emissions from ships (Tier III) has considerably decreased NOx emission limits for recreational ships with less than 500 gross tonnages and greater than 24 m load line length (LLL), the so-called “large yachts”. For these yachts, which adopt multiple Diesel engines with maximum power ranging from 800 to 2000 kW, the new NOx limit is less than 2 g/kWh. To satisfy that limit, engine makers suggest the adoption of a classic SCR system with urea injection but this methodology, in addition to requiring a large space for installation, does not seem so appropriate for diesel engines of large yachts that normally operate at low power with exhaust temperatures often well below 300 °C, therefore not sufficient to allow the correct functioning of the SCR. The aforementioned circumstances have prompted Sanlorenzo Spa (La Spezia – Italy), one of the world’s leading companies in the production of pleasure boats, to collaborate with the University of Pisa in the study of alternative solutions to SCR systems. Recently there is a great interest in innovative NOx abatement systems, based on the possibility of absorbing NOx molecules into seawater through the utilization of appropriate aqueous solutions containing targeted saline oxidizing agents. The present study describes the first results of a research program aimed to identify, from one side, the best saline oxidizing agent for an aqueous NOx abatement and, from the other, the best washing methodology compatible with the propulsion layouts usually adopted on yachts. In the engine testing laboratories of the Department of Energy, Systems, Territory and Construction Engineering (DESTeC) of the University of Pisa, an experimental apparatus has been created to reproduce the real conditions of underwater engine exhausting. This device was combined with a small 1.2 L direct injection diesel engine. The first results showed a reduction of the NOx emissions of about 27% by using a gas washing with wet scrubber, followed by bubbling in water, using 0.2 molar NaClO saline solutions.

EVALUATION OF THE QUALITY STANDARDS OF THE WATER DISCHARGED INTO THE SEA AFTER WASHING THE EXHAUST GASES

The main objective of this paper is to propose technical solutions for monitoring and recording data for a gas washing system on board a ship and to maintain in standard parameters the quality of surface water following the discharge of gas washing water from installations from the ship.The specific objectives of achieving the general objective are: the methods for evaluating the laboratory samples from the washing water evacuation, modeling the dynamics of the washing water and modeling the dispersion of the scrubber washing water on board for a case study,evaluation of the quality standards of the water discharged into the sea after washing the gases, the elements of calculation, modeling and graphical representation are present