Stainless Steel Packing Research Articles

Study on chemical absroption absrober with polypropylene packing for Guohua Jinjie CCS demonstration project

The hydrophilic modified polypropylene structured packing could lower the absorber investment in carbon capture process with chemical absorption method. While the pressure drop of the polypropylene packing is higher than that of the stainless steel packing with the same specific surface area. The optimal absorber with polypropylene and stainless steel structured packing for Guohua Jinjie CCS demonstration project was studied in this paper. The contact angle, effective surface area and pressure drop of the hydrophilic modified polypropylene packing 250Y are measured firstly. The economic analysis model which includes absorber investment (shell, packing and other internals) and operating cost (blower and lean solution pump operating expense) is built.The minimum total cost of the absorber with polypropylene packing 250Y and stainless steel packing 125–500Y are obtained. The absorber with stainless steel packing 250X/Y exhibits the lower investment and operating cost among the stainless steel packing. The minimum total cost of the absorber with stainless steel packing 250X/Y is about 0.955 $/t CO2 under 48% flooding. For the CO2 absorber of the Jinjie CCS project, the absorber with polypropylene 250Y is just about 59.5% of that with SUS304 250Y. In addition, the absorber investment, blower and pump cost with polypropylene 250Y is 27.37% lower than that with SUS304 material. The hydrophilic modified polypropylene packing 250Y can replace the stainless steel packing from the economic analysis.

Tuning the wettability of wire mesh column: pore-scale flow analysis

The pore-scale behaviour of liquid flow over wire mesh stainless-steel packing of variable contact angle is relevant for mass and heat exchanges in multiphase chemical systems. This behaviour was investigated by imaging experiments and 3D volume-of-fluid modelling. The surface of the wire mesh ring was modified by alumina coating to reach both hydrophilic and hydrophobic characteristics. The cycle of capillary droplet flow over the uncoated ring exhibited penetration of the hydrophilic mesh openings, adherence to the surface of the ring and accumulation as drips at the bottom region of the rings. However, over the hydrophobic ring, the droplet exhibited low adherence to the ring surface, accumulation at the top surface of the ring, no penetration of the openings, slip by the gravitational forces over the vertical curvature and accumulation as drips at the bottom region. In agreement with the classical observations at the macroscale, the observations at the pore-scale confirmed the increase of the wetting efficiency, liquid holdup and effective surface area at increased liquid flowrate and reduced contact angle. The 3D model was in reasonable agreement with Stichlmair's model for the liquid holdup, particularly in the hydrophilic zone of the contact angle and low flow as well as in a reasonable agreement with Linek's model for effective area, particularly in the hydrophobic range of the contact angle.

Commissioning of the LPCE and purification systems as front-end of the experimental pilot plant for D-T separation

Abstract Liquid Phase Catalytic Exchange (LPCE) as front-end process and Cryogenic Distillation (CD) as back-end process are key processes in detritiation of heavy water used in Cernavoda CANDU-type Nuclear Power Plant (NPP) from Romania as neutron moderator and in the primary heat transfer system. Same technology is used in the Water Detritiation System (WDS) of International Thermonuclear Experimental Reactor (ITER) from Cadarache, France, in order to recover tritium from moderately tritiated water. The purpose of this paper is to give a detailed overview of the current status for the front-end of the ICSI pilot plant, LPCE and purification systems, including all process components. Additionally, the paper will present the results of the non-radiological commissioning of the actual LPCE. The tests were made using protium and deuterium in order to have the confirmation of fully availability for all systems, to verify the operability in manual and automate mode for all sequences involved by start-up, normal operation and safe shut-down of the installation. The principal results consist in the safety and operability design confirmation. Secondly we present the mass transfer data of LPCE column equipped with catalytic package COMPACK C–P 001 consisting of the structured B7 stainless steel packing manufactured and patented by ICSI and a Pt/C/PTFE hydrophobic catalyst at the commissioning low concentration heavy water tests.

Astin C Production by the Endophytic Fungus Cyanodermella asteris in Planktonic and Immobilized Culture Conditions.

The fungal endophyte Cyanodermella asteris (C. asteris) has been recently isolated from the medicinal plant Aster tataricus (A. tataricus). This fungus produces astin C, a cyclic pentapeptide with anticancer and anti-inflammatory properties. The production of this secondary metabolite is compared in immobilized and planktonic conditions. For immobilized cultures, a stainless steel packing immersed in the culture broth is used as a support. In these conditions, the fungus exclusively grows on the packing, which provides a considerable advantage for astin C recovery and purification. C. asteris metabolism is different according to the culture conditions in terms of substrate consumption rate, cell growth, and astin C production. Immobilized-cell cultures yield a 30% increase of astin C production, associated with a 39% increase in biomass. The inoculum type as spores rather than hyphae, and a pre-inoculation washing procedure with sodium hydroxide, turns out to be beneficial both for astin C production and fungus development onto the support. Finally, the influence of culture parameters such as pH and medium composition on astin C production is evaluated. With optimized culture conditions, astin C yield is further improved reaching a five times higher final specific yield compared to the value reported with astin C extraction from A. tataricus (0.89 mg g-1 and 0.16 mg g-1 respectively).

Experimental study of the flow and heat transfer of a gas–water mixture through a packed channel

Waste heat recovery from the flue gas of gas-fired boilers was studied experimentally by measuring the flow and heat transfer of air and water through six kinds of packing with saturated humid air as the simulated flue gas. The experiments measured the effects of inlet air temperature, inlet air velocity and circulating water flow rate on the flow and heat transfer. The results show that higher inlet air temperatures and lower inlet air velocities lower the flow resistance and increase the heat transfer coefficient. The stainless steel packing had better surface wettability and larger thermal conductivity than the plastic packing, which enhanced the heat transfer between the water and the saturated moist air. When both the flow resistance reduction and the heat transfer enhancement were considered, the experimental results gave an optimal packing-specific surface area. A packed heat exchanger tower was designed for waste heat recovery from the flue gas of gas-fired boilers based on the experimental results which had better flow and heat transfer characteristics with lower pump and fan power consumption, more stable system operation and less thermal fluctuations compared with a non-packed heat transfer system with atomized water.

Influence of Gas-Liquid Distribution Inducer on Mass Transfer Coefficient in Rotating Packed Bed

Based on acetone-H2O system, the influence of the gas-liquid distribution inducer on the mass transfer coefficient in the rotating packed bed with the stainless steel packing was investigated. Furthermore, the absorption performance was also obtained under the experimental condition of the rotational speed of 630 rpm, the gas flow rate of 2 m3/h and the liquid flow rate of 100 L/h in the rotating packed bed with different types and different installation ways of the distribution inducer. The experimental results showed that the volumetric mass transfer coefficient Kyα per unit contact length of gas-liquid was increased by 8.6% for the forward-curved fixed blade, by 19.8% for the backward-curved rotor blade and by 33.2% with the combination of the straight radial rotor blade and the backward-curved fixed blade, respectively. Furthermore, when the gas flow rate was 2.5 m3/h, Kyα per unit contact length of gas-liquid was increased by 2.9% for the forward-curved fixed blade, by 25.3% for the backward-curved rotor blade, by 42.7% for the combination of the straight radial rotor blade and the backward-curved fixed blade, respectively. The results indicated that the distribution inducer play an important role on the improvement of the mass transfer coefficient in acetone-H2O system.

The Research of the Key Problem of Evaporative Cooling System in Dry Areas Subway

Determined direct evaporative cooling with Lanzhou subway summer air-conditioning outdoor calculated dry bulb and wet bulb temperature of 28.2°C and 18.1°C respectively. In turn, by simulating the entry conditions, tested the stainless steel packing, the aluminum foil packing, the plant fiber packing, the glass fiber packing and polymer filler packing 5different packing types at the different thickness, different face velocity and different combination of water spray density of direct evaporative cooling efficiency and resistance, ultimately determined to use the stainless steel packing. Tested the stainless steel packing small prototype, preliminarily determine the best thickness is 450mm; the best face velocity is 3m/s; the

Performance of TS-1-Coated Structured Packing Materials for Styrene Oxidation Reaction

Titanium silicalite-1 (TS-1)-coated on stainless steel packing rings of complex geometries provided a large interfacial contact area for improving mass transport processes. Zeolite seeds were assembled using organic linker, and a thin uniform layer of TS-1 catalyst was deposited on the surface by hydrothermal regrowth. The chemical, structural, and catalytic properties of the TS-1 layer were examined. An order of magnitude higher styrene conversion rate was obtained from the TS-1-coated substrates compared with powder. The catalyst was sensitive to pretreatment, and heat treatment in nitrogen provided a 30% higher conversion rate than the air-calcined samples. The N2-pretreated catalyst displayed lower activity loss and better regenerability.

Recovery Technology of DMF from Wet Type Polyurethane Synthetic Leather Waste Gas

A new recovery technology is developed to recycle N, N-dimethyl formamide (DMF) in waste gas from wet type polyurethane synthetic leather industry. Given that the concentration of DMF in waste gas was as low as 325.6–688.3 mg·m −3, it was necessary to make sure two phases contact adequately and strengthen the mass transfer by increasing contact area and enhancing the turbulence. Therefore, two-stage countercurrent absorption and two-stage fog removing system were introduced into the technology. The top section of the absorption column was filled with structured wire-ripple stainless steel packing BX500, while the lower section with sting-ripple packing CB250Y. Total height of packing material was 6 m. In addition, there were both two-stage fog removing layer and high efficiency liquid distributor at the column top. All the operating parameters, including temperature, pressure, flow rate and liquid position, could be controlled by computers without manual operation, making sure the outlet gas achieved the national emission standard that the DMF concentration should be below 40 mg·m −3. The whole equipment could recover 237.6 t of DMF each year, with the profit up to CNY 521×10 3.

Effect of a new high porosity packing on hydrodynamics and mass transfer in bubble columns

The experimental study is aimed at investigating the effect of a high porosity stainless steel packing (solid fraction being equal to 0.5%) and the influence of alcohol (0.5% volume) addition on the hydrodynamics and the gas–liquid mass transfer characteristics of bubble column reactors. This particular packing is a stainless steel welded grid with a mesh size of 12.5 mm. Measurements were carried out in a 0.2 m diameter and 4.5 m height bubble column, operating with air–water and air–ethanol solution (0.5% volume) systems in co-current upflow. A perforated plate gas sparger was used. Using, several measuring techniques, systematic measurements of average gas hold up, local gas hold up, bubble size, liquid axial dispersion coefficients and volumetric mass transfer coefficients were performed. Experiments were carried out for several values of gas and liquid velocities with and without the packing. It is observed that the packing has a large effect on gas hold up, slip velocity, radial gas hold up profile, bubble diameter, liquid mixing and gas liquid mass transfer. Gas hold up and mass transfer characteristics of packed bubble columns are found to be superior to those of bubble columns and the axial dispersion coefficients are much lower. The results obtained also show that the alcohol addition leads to larger mass transfer characteristics. The effect of both the packing and the alcohol addition can be attributed to the delay in transition from homogenous to heterogeneous gas flow regime and thus enhancing the range of homogeneous gas flow regime. The packing can be introduced to control the hydrodynamics and mass transfer characteristics of bubble column. Moreover, it can be used to support a catalyst at high pressure and temperature.

Effect of an electric field on the heterogeneous nucleation and crystal growth of potassium hydrogen tartrate in wines

Potassium hydrogen tartrate (KHT) is a naturally occurring salt in wines. To avoid the formation of KHT crystals in bottles, it is necessary to stabilize wines before bottling. However, none of the current techniques is fully satisfactory. A new process, called the ‘trap process’, has been developed that consists of cold-crystallizing KHT on a stainless steel packing. To accelerate the heterogeneous nucleation and/or crystal growth rate of the salt, the influence of an external electric field on these phenomena was studied. A potentiostatic circuit maintained a constant potential against a saturated calomel electrode. A preliminary cyclic voltammetry study led to the determination of the most suitable potential values (i.e., inducing no electrochemical reaction). A set of wine stabilization experiments was then performed using the ‘trap process’ with and without potential. The results demonstrated that a potential of +200 mV vs SCE generates an increase in process efficiency, even in the case of wines containing a lot of inhibitors. It also significantly reduces the induction time of nucleation.

On the achievement of uniform packing for dta samples

Differential thermal analysis (DTA)is a physico-chemical characterization technique that has experienced a very large growth in popularity in recent years. This has been due, at least in part, to improvements in equipment and materials used in thermal analysis studies. One of the most widely used commercial instruments is the Du Pont Model 900 Differential Thermal Analyzer, as data from a recent round-robin study have shown [1]. In attempting to obtain reproducible results on a series of finely divided inorganic materials using the Model 900 accessory high temperature cell, it was found that sample size and the packing density of the sample were difficult to control when customary packing methods were used and different people performed the experiments. Lack of reproducibility and the significant effects of differences in sample mass, thermal conductivity and thermal diffusivity, due to differences in the bulk density of the packed sample, are well known in the field of thermal analysis (see, for example, [2]). A simple sample packing device was fabricated to overcome these problems and is shown diagrammatically in Fig. 1. The base and the 3-legged sample cup holder (only two legs of which are shown) are made of brass. The legs are threaded brass rods screwed into the body and positioned with brass nuts to seat the holder in a level position in conical holes drilled into the base. The sample cup cavity is thus kept in a plumb position. Mounted on the base plate with an adjusting nut is a stainless steel threaded rod shaped into a rounded tip at the end. This tip makes an indentation in the bottom of the platinum foil liner of the 4 mm diam. platinum sample cup, as shown in the exploded view in Fig. 1, in the same way as does the thermocouple bead when the shank of the filled sample cup is mounted over the bead in the high temperature cell of the instrument. Thus, disturbance of the sample in subsequent handling is minimized. The stainless steel packing tool is shown in tamping position, packing the sample into the cup in increments by virtue of its 64 g mass. The other parts of the tool are for reshaping the platinum cups and for pushing the shank of the cup out of the holder for easier removal after packing.

Effect of surface treatment on the efficiency of stainless steel packings

AbstractThe separation efficiency of triangular‐pyramid‐type Stedman packing made from stainless steel gauze has been investigated with both organic and aqueous test mixtures at atmospheric and under reduced pressure. For the organic system the packing was found to be most efficient at 310 mm. Hg. With the aqueous test mixture, scatter and irreproducible results were obtained and it has been shown that this was due to the wetting characteristics of the stainless steel gauze. Untreated stainless steel packing is unsuitable for heavy‐water concentration. Improvement in the wetting properties of the gauze by treatment with potassium permanganate led to similar efficiency with both aqueous and organic test mixtures.