Methanol Combustion Research Articles

Optical experiment study on Ammonia/Methanol mixture combustion performance induced by methanol jet ignition in a constant volume combustion bomb

Ammonia as an alternative fuel has shown great potential in reducing carbon dioxide emissions. However, the issues of high ignition temperature and unstable combustion of ammonia limit its extensive application. As an ignition energy enhanced method, the ignition chamber (pre-chamber) seems to be an effective solution to improve the combustion performance and extend the ammonia lean flammability limit. In this study, the methanol was provided as relatively high activity fuel to improve the mixture activity in the ignition chamber and main chamber. The mixture activity control method was introduced to accelerate ammonia premixed combustion. The visualization experiment compounded with shadow method was applied to investigate. Results showed that the methanol fueled ignition chamber as jet ignition model reduced the combustion duration by almost half compared to spark ignition method. The methanol jet flame propagation formatted multiple zones of ignition and combustion in the main chamber. The ammonia combustion speed shifted from being determined by laminar flame propagation speed to being determined by jet velocity. The methanol jet velocity is related to the methanol energy substitution ratio and nozzle diameter of the ignition chamber. A 2 % methanol energy substitution ratio is optimized for the lean condition of Φ = 0.8 compared to 1 % methanol energy substitution ratio achieve for the condition Φ = 1.0 in the main chamber. When 50 % methanol (energy) was added in the main chamber, the activity thermo-atmosphere improvement induced the combustion duration to decrease by 43.8 % and 51.9 % at equivalent ratios of 1.0 and 0.8, respectively, compared to pure ammonia. The small nozzle diameter of ignition chamber can improve the jet velocity, however it caused the methanol combustion flame quenching leading to unstable combustion phenomenon. A 3 mm nozzle diameter achieved a short combustion duration compared to 4.5 mm and 6 mm nozzle diameter.

Parametric evaluation of neat methanol combustion in a light-duty compression ignition engine

Methanol is currently considered a promising alternative fuel for energy de-fossilization due to its simplicity and adequacy for renewable production. This study investigates the feasibility of using neat methanol in high-efficiency compression ignition engines, with a focus on its potential to reduce CO2 emissions compared to conventional diesel. However, achieving efficient combustion of neat methanol in compression ignition engines presents challenges due to its low ignition capability, requiring higher compression ratios, intake temperatures, and pressures than diesel for autoignition. Furthermore, the high latent heat of vaporization contributes to significant cycle-to-cycle combustion variability. This work evaluates the combustion characteristics of neat methanol in a light-duty multi-cylinder compression ignition engine with a 19:1 compression ratio, examining its suitability for commercial applications. Performance indicators such as engine efficiency, fuel consumption, and engine-out pollutant emissions are assessed. The findings contribute to advancing research and implementation of methanol fuel as an energy source for internal combustion engine vehicles, addressing both the advantages of the fuel and the challenges that need to be overcome, particularly with respect to its low auto-ignition characteristics. Notably, despite methanol's lower energy density compared to diesel, the achieved combustion efficiency is comparable, with remarkable improvements in NOx and soot emissions trade-off.The study reveals that neat methanol combustion poses difficulties, especially at low loads, speeds, and during engine startup, due to its high ignition energy requirement and long ignition delay. Even with modifications such as increased compression ratio, and the addition of intake heaters and glow plugs, sustaining combustion at low load conditions remains a challenge. However, once the engine is warmed up, methanol combustion can be sustained at medium to high loads without additional heating accessories, although the use of such accessories improves combustion stability.

Development of multilevel amplified methanol steam reforming microreactor with high hydrogen production rate

Methanol steam reforming using microreactors has been regarded as a promising approach for in-situ hydrogen production, while the generally low hydrogen production rate limits its real application. This study proposed a multilevel series scaled-up methanol steam reforming microreactor with the aim to improve the hydrogen production rate, five methanol combustion chambers are parallel arranged and interspersed into the steam reforming chambers to improve the temperature heating rate and temperature distribution uniformity. A numerical model of methanol steam reforming chamber was established to investigate the flow velocity distribution inside the chamber. The flow velocity in the copper foam region are uniformly distributed, the variations of average flow velocity in cross sections of the copper foams are below 20 %. Experimental results showed that the temperature differences between different layers was lower than 6.7 °C and the variation is smaller than 7.3 °C. A stepwise methanol solution feeding rate test was performed and found the developed microreactor has a quite rapid response speed, the maximum reformate flowrate of 20683 ml/min can be achieved with methanol conversion of 88.3 %. The developed microreactor can significantly improve the hydrogen production rate and temperature distribution uniformity, indicating a potential application in high hydrogen consumption equipment.

Visualization investigation of jet ignition ammonia-methanol by an ignition chamber fueled H2

Ammonia is an ideal carbon-free fuel if the burning velocity problem can be successfully addressed. Blending ammonia with high-activity fuels and utilizing high-energy ignition are both suitable solutions for accelerating ammonia combustion. In this study, jet-controlled compound ignition (JCCI) by an ignition chamber fueled H2 was proposed to accelerate the premixed ammonia /methanol combustion. Visualization experiments were applied to evaluate the combustion performance. The effects of hydrogen energy substitution ratios (Ri) in the ignition chamber, methanol blend (Rm) in the main chamber, and orifice diameters (d) between the ignition chamber and main chamber on the combustion were investigated. By utilizing JCCI, it achieved a combustion duration of 85 ms, which is 47.7% shorter than spark ignition (SI) under an equivalent ratio of 1.0. Furthermore, JCCI produced excellent lean burn performance. At the equivalent ratio of 0.8 and 1.0 in the main chamber, JCCI model shortened the combustion duration by 20.9% and 52.2% respectively, compared with SI ignition. Additionally, it is necessary to adapt the appropriate hydrogen energy substitution ratio for different equivalent ratios of ammonia blends. For the equivalent ratio of 1.0 and 0.8 in the main chamber, the Ri = 1% and Ri = 2% achieved shorter jet delay and combustion duration, respectively. In addition, when the equivalent ratio was 1.0 and the methanol blend ratio Rm = 10%, Rm = 30% and Rm = 50%, the combustion duration reduced by 11.9%, 28.0%, and 42.1%, respectively, compared to Rm = 0%. This reduction resulted mainly from changes in the jet flow and flame structures due to the various hydrogen energy substitution ratios and methanol blend ratios. Furthermore, using a 3 mm orifice diameter, compared to a 6 mm orifice diameter, caused the combustion duration to decline by 63.4% and 54.3% for equivalent ratios of 1.0 and 0.8, respectively.

SO2-tolerant mesoporous iron oxide supported bimetallic single atom catalyst for methanol removal

Among the single-atom catalysts (SACs), the bimetallic single-atom catalysts play an increasingly promising role in the oxidative removal of volatile organic compounds (VOCs) due to their high efficiency. However, it remains a significant challenge to resist SO2 poisoning in industrial applications. In this work, we report (i) the synthesis of three-dimensionally ordered mesoporous Fe2O3-supported bimetallic AuPt single-atom (denote as Au1Pt1/meso-Fe2O3) catalyst via a modified polyvinyl alcohol-protected reduction route; (ii) catalytic performance of the catalysts for methanol oxidation; and (iii) catalytic and SO2-resistant mechanism. It was found that compared with Pt1/meso-Fe2O3 and Ptnp/meso-Fe2O3, Au1Pt1/meso-Fe2O3 exhibited better catalytic activity for methanol combustion, with the temperature at 90% methanol conversion, TOFnoble metal at 120 °C, and apparent activation energy being 137 °C at a space velocity of 20 000 mL g–1 h–1, 6.51 × 10–2 s–1, and 36 kJ mol− 1, respectively. The enhanced activity was associated with the improved reducibility, methanol adsorption ability, and strong interaction between noble metal and support. The reaction pathway was deduced to follow a sequence of methanol → methoxy species → formaldehyde → formic acid → CO2 and H2O. Furthermore, the order of SO2 resistance was Au1Pt1/meso-Fe2O3 > Pt1/meso-Fe2O3 > Ptnp/meso-Fe2O3. The good SO2 resistance of the Au1Pt1/meso-Fe2O3 catalyst was attributed to the Au−Pt bimetallic single atoms uniformly dispersed on the meso-Fe2O3 with the strong ability of sulfate decomposition and the protection of the active sites by meso-Fe2O3 as a sacrificial site. This work presents a novel way for developing high-performance catalysts for VOCs elimination in the presence of SO2.

RETRACTED: Assessing methanol potential as a cleaner marine fuel: An analysis of its implications on emissions and regulation compliance

This article aims to fill a gap in existing studies by examining methanol's prospects as a cleaner marine vessel fuel and addressing the industry's challenges in reducing pollution from ship oil. The analysis focuses on methanol as a decarbonization fuel option, following its advantages compared to others through data triangulation that uses both bottom-up and top-down approaches to examine the safety concerns and environmental impacts of methanol. The findings support its use as a promising alternative to conventional marine fuels, considering regulations and safety codes related to low-flashpoint fuels and specifying key safety measures. Also, container vessels (6% of the global fleet) consume 23% of all annual bunker volume and require nearly two-thirds of the global bunker demand, along with liquid bulk tankers and dry bulk carriers. These findings, along with the current regulatory landscape and infrastructure requirements for methanol fuel distribution, pose the greatest challenges to its widespread adoption, despite successes by MAN and Wärtsilä engine manufacturers in offering high-pressure diesel combustion technology engines for burning methanol. This study provides insights that can help ASEAN adopt methanol fuel while complying with emission standards and reducing its environmental impacts.

NO-chemistry during methanol combustion from rich to lean conditions—exploring the fuel property influence mechanisms on different NO pathways

Methanol is a favorable hydrogen-based energy storage media, and fire methanol in industrial boiler and furnace can achieve renewable and carbon-free energy supplies in industrial heating field. Knowledges about NO formation during methanol combustion are very limited, and in particular that under furnace combustion condition with excess oxygen and high temperature (up to 1500 °C) was lacked. This paper examined NO generation of methanol under broader operation range. By comparing its behavior with the well-studied methane, the NO-chemistry dependence on methanol fuel property was analyzed. Results showed the fuel property of methanol has opposite influence on NO generation between rich and lean combustion. During lean combustion, the O atom concentration was greatly increased to promote the conversion of N2 to NO via N2+O↔N+NO under high temperature. This fuel-related mechanism makes NO generation being independent on residence time but closely correlated to fuel concentration. This proposed O enhanced mechanism also explains some previous observations that the contribution from NNH and N2O pathway is larger for methanol than methane at lean condition. Under fuel rich combustion, however, methanol generates NO mainly via prompt pathway, sharing the similar mechanism to methane but with much reduced level due to the decreased CHi concentration.

Effects of 2-ethylhexyl nitrate (EHN) on combustion and emissions on a compression ignition engine fueling high-pressure direct-injection pure methanol fuel

Green methanol is a good carbon–neutral fuel, but the cetane number of methanol is so low that it is unsuitable for use in conventional compression ignition engines. Stable combustion of methanol is a great challenge at low load. Cetane improver such as 2-ethylhexyl nitrate (EHN), can improve the combustion stability of low cetane number fuel. In the current work, the effects of EHN on combustion and emissions were studied on a compression ignition engine at low load by using pure methanol fuel. Four methanol fuels with different EHN addition ratios were used, namely 0 % EHN (pure methanol), 0.1 % EHN, 1 % EHN and 3 % EHN, and diesel was used as the baseline. Results show that compared with diesel, the shortened combustion duration of pure methanol is mainly caused by the shortening of premixed combustion phase. The brake thermal efficiency (BTE) of pure methanol is relatively higher than that of diesel at 120 °C intake temperature. But the BTE of diesel at 50 °C intake temperature is slightly higher than that of pure methanol. As the ENH increases, the ignition delay decreases gradually, and the BTE decreases first and then increases. The NOx emissions of methanol are lower than those of diesel, but NOx emissions increase with the increase of EHN. NOx emissions of 3 % EHN are 31 % more than those of pure methanol and 77 % less than those of diesel. The soot emissions are close to zero for all test methanol fuels. The BTE of all fuels increases initially and decreases subsequently with the delay of start of injection. The higher EGR rate, lower intake temperature and injection pressure improve the BTE of all fuel. For 3 % EHN, the lowest intake temperature is not higher than 40 °C for stable operation, and the optimal operating strategy for the highest BTE (30.5 %) is single injection, 25 MPa injection pressure, 15 % EGR rate and 40 °C intake temperature. Methanol shows 0.6 % higher optimal BTE than diesel at the operating condition.

Comprehensive assessment of methanol as an alternative fuel for spark-ignition engines

A promising pathway to defossilize the operation of spark-ignition engines is to use methanol as a fuel. This clean alternative liquid energy carrier offers major efficiency and emission benefits compared to gasoline. Its high knock-resistance and high heat of vaporization allow knock-free operation at high compression ratios while maintaining low emissions of nitrogen oxides. In addition, it is the simplest alcohol to synthesize and the distribution infrastructure for existing liquid fuels can be used. Previous research on mixture formation and combustion of methanol in passenger car sized spark-ignition engines is limited, reported on various experimental configurations, and mainly focused on one particular aspect. This study sets out to provide a coherent evaluation of the mixture formation and performance of methanol in a spark-ignition engine in comparison to gasoline by successively addressing and combining fundamental and optical spray measurements, engine experiments and complementing numerical analyses all with matching boundary conditions for these aspects. First, a theoretical analysis regarding the primary spray break-up behavior was performed using methanol and the gasoline surrogate iso-octane, which showed a comparable atomization performance between the two fuels. This theoretical result was then experimentally validated under realistic engine operating conditions on a low-pressure chamber by means of shadowgraph imaging. These investigations showed no notable differences in spray penetration length and spray angle between methanol and gasoline under the same boundary conditions. However, under realistic engine operation, the spray penetration length of methanol increased by up to 64.5% due to the increased injection duration required because of its lower energy content. In a next step, methanol was experimentally studied on a thermodynamic single-cylinder research engine with a compression ratio of 10.8. Using the same fuel injector, the combustion and emission behavior was investigated in comparison with gasoline. A load variation at an engine speed of 2500 1/min and a variation of the relative air/fuel ratio at the same engine speed and a net indicated mean effective pressure of 16 bar were performed. Depending on the engine load, methanol achieved 7%–24% higher net indicated efficiencies and a 9 bar higher maximum load compared to gasoline. At lean-burn operation, methanol not only enabled higher net indicated efficiencies exceeding 45%, however, also an extended lean-burn limit of 0.1 units. The experimental engine investigations were complemented with 0D/1D simulations, which showed that especially the wall heat transfer and the burn duration are significantly lower in the case of methanol. Finally, 3D computational fluid dynamics simulations were performed using a newly developed methanol spray model which showed that an increased fuel mass impinges the combustion chamber walls with methanol. However, toward the end of compression, the methanol wall film dropped to the level of gasoline.

Visualization study on combustion characteristics of direct-injected hydrous methanol ignited by diesel in a constant volume combustion chamber

Aiming to regulate the combustion and emission of diesel/methanol dual-fuel engine more effectively, the using of hydrous methanol was proposed in the current study. The ignition and combustion characteristics of direct-injected hydrous methanol ignited by diesel were investigated by optical diagnostics. Visualization experiments were conducted on a constant volume combustion chamber (CVCC) test bench with a dual-direct injection system. Diesel was injected into CVCC prior to methanol. The results show that adjusting water content in methanol and injection interval between diesel and methanol injection are two of the most important strategies that can control the ignition and combustion process. Higher water content in methanol results in much more heat absorption during water evaporation, which should be corresponding to longer ignition delay, longer flame lift-off length (FLOL) and lower spatial integrated natural luminosity (SINL). However, the decomposition of water under high temperature as well as high pressure condition can produce OH groups, which accelerates the combustion process. Moreover, the injection interval can alter the collision timing and position of spray plumes, which are very significant for diesel ignition and methanol combustion. There are almost no monotonic effect laws when water is introduced under different injection interval conditions. Suitable design and calibration of injection strategy is crucial for effective and clean combustion in diesel/hydrous methanol dual-direct injection mode.

Synthesis of Methanol From a Chemical Looping Syngas for the Decarbonization of the Power Sector

Abstract One promising pathway for carbon capture and utilization is represented by the coupling of chemical looping cycles with liquid fuel synthesis processes. Methanol is an interesting fuel for gas turbines engines, due to its potential reduction of NOX and particulate emissions along with the absence of SO2 emissions. In this work, methanol production from the syngas generated by a three-reactors chemical looping process is investigated by mass and energy balances. The cycle is composed by a reducer reactor, where Fe2O3 is reduced to FeO by the injection of a reducing agent; an oxidizer reactor, where FeO reacts with CO2 and H2O to produce a syngas; an air reactor, where Fe3O4 is regenerated to Fe2O3 by ambient air. The produced syngas is then sent to a methanol synthesis plant. Several syngas compositions deriving from different CO2/(H2O+ CO2) molar fractions (1–3) at the oxidizer inlet are taken into account. The resulting methanol flow rates are almost equal in all investigated configurations (about 0.35 t/h). From an energy standpoint, the required electric power is greater for higher hydrogen mole fractions in the syngas. However, the case with 75% H2 content is characterized by the greatest methanol yield (12.6%), carbon efficiency (23%) and a high feed/recirculation ratio (0.80), thus representing the most indicated configuration among the investigated ones. Finally, by burning methanol in a gas turbine, the total CO2 emissions are halved with respect to the case without the system (if the CO2 associated with biogenic carbon in the reducer reactor is considered as net-zero).

Application of methanol with an ignition improver in a small marine CI engine

Methanol, as one of the significant green fuel candidates for the combustion engines, can be produced from Power to X and biomass production. However, compression ignition (CI) of pure methanol in a combustion engine is impractical due to its low cetane rating. The strategy has gained little attention in the past, but is possible if the methanol is premixed with a fuel additive (ignition improver). In order to optimize and understand additivated methanol combustion, a phenomenological spray/packet combustion model is developed in this work. The model is used to calibrate an Arrhenius-type ignition delay equation for CI engine using additivated methanol, and the resulting calibrated ignition delay parameter is 2.14. The procedure involves to compare the modeled and experimental combustion rate profiles that are derived from a small marine CI engine by burning methanol with 3.5 % and up to 7.5 % kg/kg fuel additive. The present work finds that the phenomenological diesel combustion model methodology can be used with good accuracy, to simulate combustion rate profiles of additivated methanol in a CI engine. The model is, furthermore, able to indicate intermediate variables such as burning packet speeds, air mass, droplet mass, air/fuel equivalence ratio, and burning packet temperature for different packets of combustion.

MILD Combustion of Methanol, Ethanol and 1-Butanol binary blends with Ammonia

In the present energy transition scenario, ammonia is considered a valuable candidate as energy-dense carrier with neutral or even negative carbon balance. However, the potential high NOx emissions and the reduced oxidation process stability, at least when conventional combustion plants are used, can burden its wide utilization on large scales. In this context, MILD Combustion, due to its inherent characteristics, may greatly improve combustion stability and keep the NOx emissions at an acceptable level. On the other hand, the addition of low or no-carbon fuels from biomasses and wastes, more reactive than ammonia, may be beneficial in further improving its combustion performance and the global sustainability of the energy supply chain.In this respect, the present work analyzes the sustainability and combustion performance of binary mixtures of ammonia and low-molecular-weight alcohols in a cyclonic burner, where MILD conditions are attained by means of a strong internal recirculation, and compares them with those obtained with NH3/methane blends. Results highlighted that NH3/alcohols mixtures ensure a stable oxidation process in a wide range of operational parameters without compromising the system performance. Moreover, they showed a significant reduction of NOx emissions for NH3/alcohols mixtures, especially for fuel-lean conditions, when compared to NH3/methane blends.Experimental data were also corroborated by chemical kinetic modeling results to provide some insights on the peculiar NOx formation routes when blends of different nature are used, highlighting the interaction between carbon and nitrogen fuels kinetics.

Formation of multilayer graphene cells in liquid methanol using a dotted–pulsed laser via an additive technique

The formation of multilayer graphene cells (MGCs) in liquid methanol is studied using a dotted–pulsed laser via an additive technique. The MGCs are formed using the burning methanol processes. Thus, the resultant carbons are formed via decomposition and resolidification. The resultant microstructures were characterized using scanning electron microscopy and X-ray diffraction. The carbon bond statuses were determined using Raman spectroscopy. The electrical conductivities were measured under a He atmosphere. These results show that the resultant microstructures and their properties are similar to those of reduced graphene oxide. The proposed method using a dotted–pulsed laser via additive technique is a simple way to produce MGCs in liquid methanol.

Optical diagnostics of methanol active-thermal atmosphere combustion in compression ignition engine

Methanol has become one of the research hotspots of internal combustion engine in recent years. One method of methanol compression ignition is that create in-cylinder active-thermal atmosphere to ignite direct injection (DI) of methanol. However, the combustion essences and related mechanisms in methanol active-thermal atmosphere combustion (ATAC) have not been comprehended. In current study, the characteristics of methanol ATAC were investigated on a light-duty engine using different optical diagnostics. Polyoxymethylene dimethyl ethers (PODE2) and n-heptane were chosen as port injection (PI) fuel respectively, and methanol was used as DI fuel. The experiment results indicate that methanol ATAC with PI of PODE2 is divided into two combustion processes. One process is the premixed combustion of PODE2 and the partially premixed combustion (PPC) of methanol, which appears that the premixed blue flames of PODE2 and the partially premixed yellow flames of methanol. The other is PODE2 premixed combustion and methanol diffusion combustion, which presents that the premixed blue flames of PODE2 and the yellow spray diffusion flames of methanol. Both the heat release rate and the flame structure of methanol ATAC can be adjusted by changing DI timing. The increase of PI energy proportion advances the timing of premixed blue flames of PODE2. The DI of methanol is driven by spray diffusion flames unless the methanol injection timing is earlier than high temperature heat release of PODE2. The capability of PODE2 to make methanol auto-ignited is higher than that of n-heptane. The methanol energy proportion can achieve 70% in PODE2 case, while achieve merely 30% in n-heptane case. Kinetic analysis reveals that the ignition delay times of PODE2 are lower than that of n-heptane even at lower equivalence ratio. The KL factor of methanol diffusion flame ranges from 0.02 to 0.04, which is remarkable lower than diesel spray flames. The methanol ATAC achieves higher substitution rate of methanol and the flexible combustion process can be obtained using PODE2 as PI fuel.

Comparison of waste heat recovery exchangers of furnace combusted with different fuels

This study investigates and compares the low-temperature waste heat recovery exchangers of glass melting furnaces using liquid natural gas (LNG), methanol and dimethyl ether (DME) as fuels. A glass melting furnace with a production of 1 t/year was used to combust the fuel with air, and the waste heat exchanger served to recover the heat from the flue gas at a low temperature to preheat the air. The net present value (NPV) and carbon dioxide (CO2) emissions acted as the evaluating parameters of the heat exchanger. The results showed that the methanol combustion programme yielded the maximum NPV and carbon dioxide emissions. The LNG combustion programme yielded the lowest values and the parameters in the DME combustion programme are always in the middle. Considering the income of the heat exchanger and carbon dioxide emissions, the glass melting furnace with DME as the fuel is the optimal programme.

HCCI combustion of methanol along with diesel through novel injection strategies and its potential over conventional dual fuel combustion

In this experimental work Homogenous Charge Compression Ignition of methanol along with direct injection of diesel (HCCI-DI) was achieved by adapting novel injection strategies for controlling the charge homogeneity and ensuring proper combustion in a single cylinder common rail water cooled research engine run at a constant speed of 1500 rpm. Methanol was port injected while the diesel was injected as two pulses – an early first pulse (during start of suction) for enhancing the charge homogeneity and a late second pulse for controlling ignition. The effects of methanol energy share (MES), start of injection of the first and second pulses (SOI-F and SOI-S) and first pulse injected quantity (FIQ) at different loads were studied. The SOI-S of diesel had to be advanced with load for best thermal efficiency. At full load, it had to be retarded to limit knocking. Heat release analysis indicated that higher FIQs resulted in slow combustion as the charge was more homogeneous while lower FIQs formed a stratified mixture that enhanced the thermal efficiency, reduced THC and unregulated emissions while elevating the NOx levels. The thermal efficiencies were higher by about 2.9 and 1.9% compared to the Conventional Dual Fuel (CDF) operation at 75% and 50% loads. The MES that could be tolerated was higher than the CDF mode. Soot was significantly reduced as compared to the CDF mode by 94%, 87.6%, 80.3% while the NOx was reduced by 77.5%, 65.2% and 29.9% at the IMEPs of 5.1, 6.2 and 7.5 bar respectively. However, emissions of unburnt hydrocarbons, carbon mono-oxide, methanol and formaldehydes were higher than the CDF mode. On the whole the methanol diesel HCCI-DI mode has the potential for operation with higher efficiency, lower NOx and soot emissions than the CDF mode.

Противопожарная защита резервуаров с метанолом самовспенивающейся газоаэрозоленаполненной пеной

Polar liquids including methanol are widely used in various industries. It has unique physical and chemical properties: extreme fire and explosion hazard, corrosive activity, high toxicity. These properties determine the complexity of its extinguishing. In Russia, there is practically no normative base for the design, construction, and repair of tanks where methanol is stored. In the available recommendations for extinguishing methanol fires by «soft» method the normative intensity of alcohol-resistant foam supply to the fire source is underestimated. Alcohol-resistant foam concentrates such as AFFF/AR, FFF/AR, S/AR allow to ensure reliable extinguishing of polar liquids. To do this, it is required to determine the method of supplying the foaming agent and its standard intensity when extinguishing methanol in the tanks. Thermophysical properties of the methanol combustion (heat fluxes, burnout rate, heat release rate) determine the possibility of developing methods for its extinguishing on the model fire seats. For these purposes, the pallets with a diameter of more than 3 m can be used with a side thickness of 6 mm. To extinguish methanol, it is proposed to use a low-expansion self-foaming gas-aerosol filled foam with a standard flow rate of 0.25 l/(m2·s). Specific consumption of the fire extinguishing agent was determined: for methanol, it should be 30 l/m2 with an extinguishing time of 120 s. Foam generation can take place without the use of traditional foam generators with the help of self-contained solid fuel fire extinguishing installations. When using them, the problem of corrosion resistance of foam generating equipment is solved, and the «soft» fire extinguishing method is also implemented for the tanks with a volume of 5000 m3 or more.

Effect of injection timing on combustion, performance and emissions characteristics of methanol fuelled DISI engine: A numerical study

In this paper, the effect of the start of injection (SOI) on the engine characteristics of a methanol-fuelled direct injection spark ignition (DISI) engine is numerically studied. The simulations are performed using CONVERGE CFD software on a wall-guided, four-stroke gasoline direct injection (GDI) engine. The SOI is swept from −120° CA ATDC (crank angle after top dead centre) to −100° CA ATDC at a constant step of 5° CA. The engine speed of 2000 rpm and a compression ratio (CR) of 11:1 is used. It is observed that there exists an optimum injection timing for a given spark timing at which the best compromise is obtained between the performance and emissions. A maximum indicated thermal efficiency (ITE) of 41.66% is obtained in the case of −115° CA ATDC SOI. Emissions like formaldehyde and soot are also found to be the lowest in this case. Engine's ITE is 36% higher for methanol fuel than gasoline when simulated by supplying the same energy input, keeping all the other parameters the same. The total hydrocarbon (THC), carbon monoxide (CO), and soot emissions are 58.2%, 68%, and 73.9% lower for optimised methanol injection timing as compared to gasoline. The NOX emissions are found to be higher for methanol than gasoline due to higher in-cylinder temperature in the case of methanol engine, which is due to higher heat release and proper combustion than gasoline.

An experimental investigation of methanol combustion in low temperature supercritical water

Methanol combustion in supercritical water was systematically investigated at iso-thermal iso-baric conditions using the Eastern Michigan University Supercritical Batch Reactor. The nominal mixture was 1.5% methanol by volume with an oxygen equivalence ratio of 0.22 and a total density of 193 mg/mL; reaction times were 8–30 min with temperatures from 375° to 475 °C. The experimental observations here provide new comprehensive benchmark data for methanol oxidation near the critical point, including an evaluation of wall effects on chemical kinetics. Excellent repeatability demonstrates the effective function of the new experimental facility. The system was modeled using a custom kinetics solver and an existing chemical kinetic mechanism, with genetic optimization used for sensitivity analysis. Modeling results validate the general accuracy of an established chemical kinetic mechanism in lower temperature supercritical water and support a rate reduction for CH3OH + OH/HO2 = CH2OH + H2O/H2O2 reactions below existing uncertainty limits at these conditions.