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Developing a Work Breakdown Structure
Published in Timothy J. Havranek, Modern Project Management Techniques for the Environmental Remediation Industry, 2017
The largest risk associated with this project is the fact that it is being performed under a firm fixed price contract. The risks have been significantly reduced by the use of limiting assumptions (e.g., at least ten wells are in functioning condition, no subsurface obstructions, etc.) and a detailed scope of work (based on the notes collected during the WBS development). However, examples of project risks that may occur during project execution include: The EPA may issue a consent order for the site before it can be placed in the voluntary cleanup program.Best Auto Parts could create significant and repeated delays in site activities.The monitoring wells could be significantly silted up, requiring extra time for development.There could be a shortage of equipment needed for the HVDPE pilot test, such as the liquid ring pump. Therefore, costs for HVDPE equipment could increase.An unidentified subsurface obstruction, such as a sanitary sewer, could be penetrated during drilling operations.A significant Enviroserv team member, such as the design engineer, could leave the company halfway through completion of his or her assigned task.
Mechanical Displacement Pumps
Published in Igor Bello, Vacuum and Ultravacuum, 2017
However, the most common service medium is water. Water ring pumps have been described by several authors including Cole,412 Powle and Kar,413 and Edbale.414 The liquid ring pump is a system with a single rotor. The rotor (impeller) can be installed either eccentrically or concentrically in the stator housing. The radial cross section of the stator housing can be either circular or elliptical. The systems with the circular cross sections are constructed with single chambers (single-acting pumps), whereas those with elliptical cross sections are manufactured with two chambers (double-acting systems).
Steam Sterilization-in-Place
Published in James Agalloco, Phil DeSantis, Anthony Grilli, Anthony Pavell, Handbook of Validation in Pharmaceutical Processes, 2021
It has been noted that pre-vacuums are not the norm in SIP systems. Lyophilizers are a possible exception, as their physical design and operational characteristics makes the use of pre-vacuums more attractive. Pre-vacuums have been successfully utilized in other SIP systems where the additional complexity of the vacuum system is deemed to be offset by the more rapid steam penetration achieved. Where vacuum is utilized in any SIP system, it would be drawn using a water-filled liquid ring pump, and not the more capable, but incompatible oil-filled vacuum pumps used for deep vacuum.
Nozzle zone agglomeration in spray dryers: Process dependency of the fines mass flow and its importance for agglomerate formation
Published in Drying Technology, 2023
Jakob Alfons Fröhlich, Maren Spiess, Jörg Hinrichs, Reinhard Kohlus
The maximum absorption of the colorant was determined at 507 nm whereby an AvaLight-HAL Tungsten Halogen Light Source (Avantes BV, Apeldoorn, Netherlands) and an AvaSpec-ULS2048 UV/Vis spectrometer with AvaSoft 8.11 Basic Software was used as detector. Integration time was set to 1.05 ms and signal averaging with 100 scans was performed to reduce measurement noise. Measured absorption signals were correlated to powder mass using a calibration curve from After cooling, the particle-free air was fed to the air flow meter (Mass-View, Bronkhorst High-Tech B.V., Ruurlo, Netherlands) which ensured the isokinetic extraction velocity. The air flow was extracted by means of a liquid ring pump. The measuring time per measuring point in steady-state operation was at least 10 minutes. In another study[19] the identical measuring system was used for residence time measurements in spray dryers, whereby a response time of the measurement set-up of approx. 10 s was determined. This is thus sufficiently small compared to the measurement duration.
Prediction of airflow rate passing through compressible wet fiber web in vacuum dewatering for energy conversion improvement
Published in Drying Technology, 2023
Peng Ren, Ying Han, Xiangjun Fang, Zeyu Jiao
The selection of design point of the vacuum pump is a critical factor in its design, which is usually the highest efficiency point. As shown in Figure 11(b), there is a noticeable deviation between the predicted airflow rate of CPM and the measured value when CPM is used on the wet fiber web not used for deduction the model, such as SBK. Considering the deviation condition shown in Figure 11(b), the airflow rate at the design point of vacuum pump, chosen according to CPM, will be larger than the actual value. As shown in Figure 12, this will cause a lower working efficiency to the liquid ring pump (LRP), and for the centrifugal vacuum pump (CVP) it may not only cause a lower working efficiency but also result in a surge, which may cause a great damage to the mechanical structure of the CVP. Figure 12 shows the general performance curves of the LRP and the CVP, of which the horizontal axis is the normalized airflow rate, representing the ratio of airflow rate to the design point value. The predicted airflow rate of CPM may be less than the measured value. Under these circumstances, the working efficiency of the LRP and the CVP also lower than that at the design point, causing a waste of efficiency, i.e., energy waste. As mentioned above, VPM leads to a higher working efficiency of vacuum pump since the predicted airflow rate of VPM is more consistent with the actual value than CPM.
Analysis of the high-speed jet in a liquid-ring pump ejector using a proper orthogonal decomposition method
Published in Engineering Applications of Computational Fluid Mechanics, 2022
Li-Jie Jiang, Ren-Hui Zhang, Xue-Bing Chen, Guang-Qiang Guo
The experiment was carried out on the liquid-ring pump ejector test system set up by the research team. Figure 4(a) illustrates the test system and Figure 4(b) the schematic diagram of the test system. The test system includes the liquid-ring pump, ejector, power and control system, water feeding system, data collecting system, inlet and outlet pipeline system, etc. The ejector is connected in series with the liquid-ring pump, and its outlet is connected to the inlet of the liquid-ring pump. When the ejector is working, valve 9 is fully opened and valve 13 is closed. The secondary flow inlet vacuum is controlled by adjusting the opening of valve 14. The vacuum and flow rate of secondary fluid inlet were measured by pressure gauge 11 and orifice flowmeter 3, and the flow rate of the primary fluid was measured by turbine flowmeter 10.