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Kass, Michael D.

Publications and source records attributed to Kass, Michael D..

Assessing Compatibility of Natural Gas Pipeline Materials with Hydrogen, CO 2 , and Ammonia

Here, in this study, we examine the efficacy of repurposing natural gas (NG) pipelines for transporting hydrogen blends (with NG), ammonia, and CO 2 (gaseous and supercritical) from the standpoint of materials compatibility. Some information pertaining to component performance is also included, especially those components critical for pressurization and monitoring of flow. A listing of critical pipeline components and materials was developed, and their compatibilities was assessed for each fluid or gas type based on known compatibilities. Results indicate that pipeline materials should be suitable for gaseous CO 2 and anhydrous ammonia, but hydrogen blends greater than 12% may be problematic. Current compressor/regulator stations will not be suitable for use with either supercritical CO 2 or ammonia. Important knowledge gaps were identified, including (1) polymer performance with hydrogen/NG blends at low pressures, (2) compressor/regulator station polymers and epoxy coating materials with supercritical CO 2 , and (3) metal performances of hydrogen/NG blends at low pressures.

03 NATURAL GAS↗

Performance of Structural Alloys in Bio-oil Production, Upgrading, and Storage Systems

Selection of corrosion-resistant, cost-effective structural materials for the process and containment vessels required for the production, upgrading, and storage of biomass-derived oils has been the subject of study in our laboratory for many years. The wide variety of biomass resources and the many liquefaction techniques and processing conditions result in products with a broad range of properties and compositions. Here, this paper will address the materials issues in three distinct areas. In production, materials are exposed to temperatures that range from 350 to 550 °C depending upon the process. Generally, austenitic stainless steels have performed reasonably well, although thicker oxide scales and intergranular attack have sometimes been observed. For storage and transport of the bio-oil products, temperatures experienced by the containment materials are not expected to exceed 50 °C. Our studies have shown that most raw bio-oils contain significant concentrations of organic acids, and low-molecular-weight organic acids were quite corrosive to carbon and low alloy steels. For some applications, subsequent processing is required, which includes hydrotreating or co-processing with a petroleum-derived liquid. These processes utilize a catalyst that requires periodic retreatment with a sulfidizing gas, and the exposure to this gas at elevated temperatures can cause appreciable corrosion to the more common austenitic stainless steels. The materials considered most cost-effective and sufficiently corrosion-resistant for each of these environments were identified.

36 MATERIALS SCIENCE↗

Corrosion Compatibility of Stainless Steels and Nickel in Pyrolysis Biomass-Derived Oil at Elevated Storage Temperatures

Corrosion compatibility of stainless steels and nickel (Ni200) was assessed in fast pyrolysis bio-oil produced from pyrolysis of high ash and high moisture forest residue biomass. Sample mass change, ICP-MS and post-exposure electron microscopy characterization was used to investigate the extent of corrosion. Among the tested samples, type 430F and type 316 stainless steels (SS430F and SS316) and Ni200 (~98.5% Ni) showed minimal mass changes (less than 2 mg∙cm−2) after the bio-oil exposures at 50 and 80 °C for up to 168 h. SS304 was also considered to be compatible in the bio-oil due to its relatively low mass change (1.6 mg∙cm−2 or lower). SS410 samples showed greater mass loss values even after exposures at a relatively low temperature of 35 °C. Fe/Cr values from ICP-MS data implied that Cr enrichment in stainless steels would result in a protective oxide layer associated with corrosion resistance against the bio-oil. Post exposure characterization showed continuous and uniform Cr distribution in the surface oxide layer of SS430F, which showed a minimal mass change, but no oxide layer on a SS430 sample, which exhibited a significant mass loss.

09 BIOMASS FUELS↗

Measurement of Piston Deposit Thickness Using Laser Profilometer

In this work, a novel method of measuring the thickness of deposits on engine pistons, including within ring grooves, is described. A laser profilometer is used in conjunction with a rotary stage to measure a continuous profile of the piston with deposits, and the measurement is repeated after cleaning the deposits from the piston. Algorithms for aligning the scans and determining the differential thickness are described, and results are compared to deposit thickness measurements using a contact-type magnetic induction coating thickness gauge. This method allows continuous measurement of deposit thickness across the entire surface including lands and ring grooves as well as quantification of the volume of the deposits.

42 ENGINEERING↗

Effect of Carboxylic Acids on Corrosion of Type 410 Stainless Steel in Pyrolysis Bio-Oil

Biomass-derived oils are renewable fuel sources and commodity products and are proposed to partially or entirely replace fossil fuels in sectors generally considered difficult to decarbonize such as aviation and maritime propulsion. Bio-oils contain a range of organic compounds with varying functional groups which can lead to polarity-driven phase separation and corrosion of containment materials during processing and storage. Polar compounds, such as organic acids and other oxygenates, are abundant in bio-oils and are considered corrosive to structural alloys, particularly to those with a low-Cr content. To study the corrosion effects of small carboxylic acids present in pyrolysis bio-oils, type 410 stainless steel (SS410) specimens were exposed in bio-oils with varying formic, acetic, propionic and hexanoic acid contents at 50 °C during 48 h exposures. The specific mass change data show a linear increase in mass loss with increasing formic acid concentration. Interestingly, a mild corrosion inhibition effect on the corrosion of SS410 specimens was observed with the addition of acetic, propionic and hexanoic acids in the bio-oil.

09 BIOMASS FUELS↗

Compatibility of Fuel System Elastomers and Plastics with a Fast-Pyrolysis Oil (Bio-oil) at Room Temperature

Herein the compatibility of a fast-pyrolysis bio-oil with 17 elastomer and 21 plastic materials common to fuel storage, dispensing, and delivery systems was assessed by measuring volume and hardness. Diesel was used as the baseline for comparison. The elastomer and plastic specimens were exposed to the test fuels at 23 °C. The exposure times were 4 and 16 weeks for the elastomers and plastics, respectively. The elastomers (except for silicone and styrene butadiene) exhibited pronounced swelling in the bio-oil. This was especially true for the fluorocarbons and acrylonitrile rubbers. For the elastomers, a strong correlation between polarity and volume swell was observed. Compositional and structural analysis on one of the fluorocarbon materials showed that the bio-oil was less effective at extracting phthalate additives than the diesel. However, the crystallinity of a fluorocarbon was altered by the bio-oil. Unlike the elastomers, the plastic materials were less impacted by exposure to the bio-oil. This finding is attributed to their denser and more rigid molecular structures (compared to the elastomers). Notable swelling did occur in the nylons, but this swelling was attributed to water absorption rather than polarity. Comparison with previous studies showed that the observed swelling was lower for both the elastomers and the plastics. Solubility (and hence swell) increases with temperature, and because this study was conducted at 23 °C rather than 50 °C, the reduced temperature is responsible for the lower swell levels.

09 BIOMASS FUELS↗

n-Butanol or isobutanol as a value-added fuel additive to inhibit microbial degradation of stored gasoline

Biofouling of gasoline can occur during fuel storage caused by bacteria and fungi that form a biofilm at a fuel/water interface and that produce organic acids and sulfides. Fuel additives are applied to gasoline to prevent biofouling but are relatively expensive, are not always effective against biofilms, and do not contribute to the combustibility of gasoline. Bio-isobutanol is an approved, certified advanced biofuel and is added up to 16% ( v/v ) in gasoline blends “iBut16”; n-butanol blends are currently under review. Microorganisms are inhibited by n-butanol or isobutanol when the aqueous concentration reaches >2-3% (w/ v ). We determined that n-butanol partitions into the aqueous phase of a model gasoline/water system reaching concentrations of 42 g/L and up to 48 g/L from gasoline blends at 10% and 24% ( v/v ), respectively. Likewise, isobutanol blended in gasoline at 10% and 24% ( v/v ) partitioned into an aqueous phase at 45 g/L and 53 g/L, respectively. Several bacterial and fungal strains that originate from fuel storage tanks, or are known to be solvent tolerant, were evaluated for their potential growth in a range of n- and isobutanol concentrations. Growth rates for all strains tested were reduced by 40–100% relative to untreated controls in n- and isobutanol concentrations of 1.5 and 2.0% ( v/v ). No observable growth occurred for any of the microorganisms in solvent concentrations at 3.0% ( v/v ). T amphiphilic and chaotropic properties of n- or isobutanol help them inhibit microbial growth and could serve as effective biocides during fuel storage as well as being valuable fuel additives.

59 BASIC BIOLOGICAL SCIENCES↗

The compatibility performance of fuel system elastomers with two dioxolane molecules as blends with diesel

The compatibility of 17 elastomers with two dioxolane molecules was assessed by volume change and hardness measurements. Each molecule was blended with diesel in concentrations of 0, 10, 20 and 30 wt.%. The elastomers included two fluorocarbons, six acrylonitrile butadiene rubbers (NBRs), and one each of fluorosilicone, chloroprene rubber (CR), polyurethane, styrene butadiene rubber (SBR), hydrogenated NBR (HNBR), a blend of NBR and PVC (OZO), epichlorohydrin/ ethylene oxide (ECO), ethylene propylene diene monomer (EPDM), and silicone. Specimens of each elastomer were immersed in the test fuels for a period of 4 weeks and measured for property change. Afterwards they were dried at 60°C for 20 h and remeasured. The results showed that the dioxolanes were suitable with many of the elastomers and that the performances were essentially the same for both molecules. The dioxolanes were found to either have negligible impact beyond neat diesel or they produced a small increase in swell. This minimal impact is attributed to the fact that the solubility parameters (especially those associated with polarity and hydrogen bonding) of the dioxolanes are similar to those of diesel. As a result, little change in solubility and hence swell occurred when dioxolane was added to the diesel.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Corrosion of Ferrous Structural Alloys in Biomass Derived Fuels and Organic Acids

This work investigated the corrosivity of biomass-derived liquid fuels and organic acids associated with bio-oils and conducted a corrosion compatibility evaluation of several structural ferrous alloys in the fuels and acids. Here, the acidity parameters and solution conductivity values were higher in raw pyrolysis bio-oils than postprocessed oils with significant corrosion attack for carbon steel and Fe-2.25Cr-1Mo. However, higher-grade stainless steels, ferritic Fe-15Cr (15Cb) and austenitic types 304L and 316L, showed negligible corrosion loss, whereas lower-Cr ferritic grades 409, 410, and 416 were attacked. Metal leaching tests and electrochemical impedance spectroscopy measurements revealed superior corrosion resistance of 316 over 410 stainless steels in solutions of formic and oxalic acids that can be present in bio-oils. The corrosion evaluation methods utilized in this work provide effective screening tools to identify the compatible structural alloys for bio-oils.

09 BIOMASS FUELS↗

Top 13 Blendstocks Derived from Biomass for Mixing-Controlled Compression-Ignition (Diesel) Engines: Bioblendstocks with Potential for Decreased Emissions and Improved Operability

Reducing the impacts of medium- and heavy-duty (MD/HD) ground transportation can be enabled by fuel-engine combinations that use lower compression ignition liquid fuels and reduce criteria pollutant emissions. Fuels and blendstocks combined with advanced engine technologies could reduce the cost of ownership and the emission of pollutants, including soot, nitrogen oxides (NOx) and greenhouse gases (GHGs), from MD/HD vehicles. This report describes the evaluation and screening of MD/HD mixing-controlled compression ignition (MCCI) biofuel candidates for further development and commercialization. The report is aimed at 1) biofuel researchers looking to better understand options to reduce criteria pollutant and GHG emissions while maintaining efficiency and meeting requirements for engine operability and 2) engine researchers who want to evaluate biofuels that meet diesel fuel properties for their impact on conventional and advanced diesel combustion strategies.

09 BIOMASS FUELS↗

Spill Behavior, Detection, and Mitigation for Emerging Nontraditional Marine Fuels

In this report, we describe the predicted impact of large spills or releases of alternative marine fuels. The fuels covered in this report are those that have been identified as potential future fuels for the marine shipping sector by industry experts and government agencies overseeing the development of renewable and low-carbon fuels. Several of these fuels are already in use, such as liquified natural gas, renewable diesel, ethanol, methanol, and biodiesel. Other fuels are hydrogen, dimethyl ether, ammonia, and bio-intermediates, such as catalytic fast pyrolysis biooils and hydrothermal liquefaction bio-crudes. The property databases of these fuels are extensive enough to form predictive assessments. Other potential marine fuels, such as lignin ethanol, have not been extensively evaluated and are therefore not included is this study. For each fuel chemistry, we have surmised the spill profiles and environmental impacts based on existing studies and relevant properties. The technologies used to detect spills (especially those for crude oil detection) are also reviewed for their applicability with alternative fuels, and in some instances, recommendations to improve these technologies for use with a particular fuel chemistry are put forward. Finally, current containment and remediation technologies are reviewed and assessed for their efficacy at handling these alternative fuels.

04 OIL SHALES AND TAR SANDS↗

Stability, Combustion, and Compatibility of High-Viscosity Heavy Fuel Oil Blends with a Fast Pyrolysis Bio-Oil

Properties related to the combustion, stability, and compatibility of blends composed of high-viscosity heavy fuel oil (HFO) and highly acidic pyrolysis bio-oil were determined to assess the utility of bio-oil as a marine fuel. The addition of bio-oil was shown to be fully stable with HFO at blend levels up to 50 mass % for up to 2 weeks. Bio-oil concentrations as low as 5 mass % significantly reduced the viscosity of HFO at 25 and 50 °C. Aging studies at 50 and 90 °C showed that the HFO inhibited the polymerization of bio-oil. The heating value and lubricity showed a linear dependency with bio-oil content, and combustion quality was acceptable for blends containing up to 15% bio-oil. The highly acidic bio-oil was found to be corrosive to carbon steel, 2.25Cr-1Mo steel, and 409 stainless steels, but not 304L and 316L. When blended into HFO at levels less than 19 mass %, no measurable corrosion was observed on any of the steel materials, but a 50 mass % concentration produced low-to-moderate corrosion in the carbon steel, 2.25Cr-1Mo steel, and 409 stainless steel grades. The combination of good blend stability, polymerization inhibition, reduced viscosity, and acceptable compatibility for low blend levels suggests that bio-oils may be suitable for use as a marine fuel.

09 BIOMASS FUELS↗

Screening of Potential Biomass-Derived Streams as Fuel Blendstocks for Mixing Controlled Compression Ignition Combustion

Mixing controlled compression ignition or diesel engines are highly efficient and are likely to continue to be the primary means for movement of goods for many years to come. Low-carbon biofuels have the potential to significantly reduce the carbon footprint of diesel combustion and could potentially have advantageous properties for combustion such as high cetane number and reduced engine out particle emissions. In this study, we developed a list of potential biomass-derived diesel blendstocks. An online database of properties and characteristics of these bioblendstocks was populated with data. Fuel properties were determined by measurement, model prediction, or literature review. Screening criteria were developed to determine if a bioblendstock met the basic requirements for handling in the diesel distribution system and use as a blend with conventional diesel. Criteria included cetane number =40, flashpoint =52 degrees C, and boiling point or final boiling point <338 degrees C. Blendstocks needed to be soluble in diesel fuel, have a toxicity no worse than conventional diesel, and not be corrosive. Additionally, cloud point or freezing point below 0 degrees C was required. This screening produced a list of 27 potential bioblendstocks. Of these candidates, 13 were available commercially or could be synthesized by biofuels production researchers and included 11 nominally pure components and two mixtures. These 13 candidates were then subjected to further study based on how they impact fuel properties upon blending. Blend properties included cetane number, lubricity, conductivity, oxidation stability and viscosity. Results indicate that all thirteen candidates can meet the basic requirements for diesel fuel blending and are likely to reduce particle emissions from diesel combustion.

09 BIOMASS FUELS↗