Viscosity Analysis of Battery Electrode Slurry

We report the effects of component ratios and mixing time on electrode slurry viscosity. Three component quantities were varied: active material (graphite), conductive material (carbon black), and polymer binder (carboxymethyl cellulose, CMC). The slurries demonstrated shear-thinning behavior, and suspension properties stabilized after a relatively short mixing duration. However, micrographs of the slurries suggested their internal structures did not stabilize after the same mixing time. Increasing the content of polymer binder CMC caused the greatest viscosity increase compared to that of carbon black and graphite.

Impact of particle size reduction on high gravity enzymatic hydrolysis of steam-exploded wheat straw

Economically feasible bioethanol production from lignocellulosic biomass requires solid loadings ≥ 15% dry matter (DM, w/w). However, increased solid loadings can lead to process difficulties, which are characterized by high apparent slurry viscosity, insufficient substrate mixing and limited water availability, resulting in reduced final glucose yields. To overcome these limitations, this study focused on enzymatic hydrolysis of 10–35% DM solid loadings with steam-exploded wheat straw in two different particle sizes. At solid loadings of 20 and 25% DM small particle size of ≤ 2.5 mm yielded 16.9 ± 1.1% and 10.2 ± 1.4% increased final glucose concentrations compared to large particle size of 30 ± 20 mm. Small particle size also positively influenced slurry viscosity and, therefore, miscibility. As a key finding of this investigation, high gravity enzymatic hydrolysis with solid loadings of 30–35% DM was indeed successfully employed when wheat straw was applied in small particle size. Here, the highest final glucose yield was achieved with 127.9 ± 4.9 g L−1 at 35% DM solid loading. An increase in the solid loading from 10 to 35% DM in small particle size experiments resulted in a 460% increase in the final glucose concentration.

Real-Time Slurry Characteristic Analysis During Ball Milling Using Vibration Data

The characteristics of an internal slurry were analyzed during ball milling, which is commonly utilized in ceramic processing. We used a device with a capacity of 50 L because this is the size employed in industries, and built a circulation system to collect the slurry during the milling process. The properties of the slurry were characterized in terms of their particle size and viscosity, while vibration data were collected from the side of the ball mill drum in real time. A fast Fourier transform was performed on the vibration data, allowing the energy to be calculated and compared with the slurry characteristics. The vibration data in the 3–4 kHz range showed a strong negative correlation with the slurry viscosity. Our results confirm that the characteristics of the internal slurry can be monitored in real time using vibration data collected during ball milling.

Seepage Characteristics of Slurry with Particle Additives in the High-Permeability Sand Layer

In the process of the slurry shield construction, the formation of the filter cake is the key to maintain the stability of the excavation face. In high-permeability formation, ordinary pure bentonite slurry is easy to pass through the formation void. Therefore, it is necessary to study the slurry permeability characteristics of the high-permeability sand layer. For the purpose of researching the permeability characteristics of slurry in sandy formation, this paper studies the influence of slurry viscosity on the formation of the filter cake in high-permeability formation under different pressure gradients by the slurry permeability test. The effect of additive particle size on the film-forming gain was studied by adding additives with different particle sizes into pure bentonite slurries with different viscosities. This paper presents a method to determine the optimum slurry viscosity and particle size for high-permeability formation so as to guide the slurry shield construction in high-permeability formation.

Rheology of THF hydrate slurries at high pressure

One of the main issues in the area of drilling and production in deep and ultra-deep water in the oil industry is the formation of natural gas hydrates. Hydrates are crystalline structures resembling ice, which are usually formed in conditions of high pressure and low temperature. Once these structures are formed, they can grow and agglomerate, forming plugs that can eventually completely or partially block the production lines, causing huge financial losses. To predict flow behavior of these fluids inside the production lines, it is necessary to understand their mechanical behavior. This work analyzes the rheological behavior of hydrates slurries formed by a mixture of water and Tetrahydrofuran (THF) under high pressure and low temperature conditions, close to the ones found in deep water oil exploration. The THF hydrates form similar structures as the hydrates originally formed in the water-in-oil emulsions in the presence of natural gas, at extreme conditions of high pressure and low temperature. The experiments revealed some important issues that need to be taken into account in the rheological measurements. The results obtained show that the hydrate slurry viscosity increases with pressure. Oscillatory tests showed that elasticity and yield stress also increase with pressure.