Application of Pulsating Vacuum Cleaning Technology to Medical Devices Cleaning

This study aims to solve existing problems in cleaning medical devices, such as the cumbersome loading of minimally invasive surgical instruments, the incomplete cleaning of instruments with complex structures, and the low cleaning efficiency of ordinary instruments. A pulsating vacuum cleaning machine was combined with ultrasonic cleaning and boiling cleaning technology to clean various complex medical devices through a pressure pulsating process (i.e., repetitive pump-out and pumpin until the cleaning results meet the cleaning standards for medical devices). The cleaning results of spay washing, ultrasound cleaning and pulsating vacuum cleaning were compared among four groups of medical devices, including silica gel hoses, chamber instruments, whole box of minimally invasive instruments and surgical instruments. The amount of protein residues was tested using the spectrophotometric method. The testing results revealed that the loading capacity of a pulsating vacuum cleaning machine is 3–4 times as much as that of an ordinary spray cleaning machine, without manual placement and connection operation required, which reduced the workload of pretreatment. The protein residue after cleaning meets the requirements of the YY/T0734 standard for the cleaning effect of medical devices. Pulsating vacuum cleaning technology has an overall better loading capacity, when compared to spay washing and ultrasound cleaning, and this can make up for the shortcomings of commonly used cleaning machines, such as the low cleaning efficiency and unsatisfactory cleaning results of medical devices with complex structures.

A novel alkali-surfactant for optimization of filtercake removal in oil–gas well

The main objective of this study is to improve the oil-based filtercake removal at the wellbore second interface through chemical method. The reductions in near-well permeability, bonding strength at wellbore second interface and acidizing treatment are the critical problems in oilfield upstream operations. One of the major causes has been identified as drilling fluid filtrate invasion during the drilling operations. This as result leads to near-well reduction in-flow capacity due to high drawdown pressure and wellbore instability. A number of chemical methods such as enzymes, acids, oxidizers, or their hybrids, have been used, however, due to the presence of a number of factors prior to its removal, there are still many challenges in cleaning oil-based filtercake from the wellbore surface. There is a need for development an effective method for improving oil-based filtercake removal. This study presents a novel Alkali-Surfactant (KV-MA) solution developed in the laboratory to optimize the filtercake removal of oil–gas wellbore. The Reynold number for KV-MA solution was found to be 9,068 indicating that turbulent flow regime will dominate in the annulus which enhances the cleaning efficiency. The wettability test established that, contact angle of 14° was a proper wetting agent. The calculated cleaning efficiency was 86.9%, indicating that it can effectively remove the oil-based filtercake. NaOH reacts with the polar components in the oil phase of the oil-based filtercake to produce ionized surface-active species; hence reducing the Interfacial Tension. Surfactant quickens the diffusion of ionized species from the interface to the bulk phase.

Numerical Simulation of Effective Hole Cleaning by Using an Innovative Elliptical Drillpipe in Horizontal Wellbore

In the drilling of horizontal wells, the drill cuttings tend to settle down on the low side of the annulus due to gravity and form a stationary bed, which results in hole cleaning problems. In this paper, a novel type of drillpipe with an elliptical shape was proposed to alleviate inadequate hole cleaning during the drilling of horizontal wells. A three-dimensional computational fluid dynamic (CFD) Eulerian-Eulerian approach with the Realizable k-ɛ turbulence model was developed to predict the solid–liquid two-phase flow in the annular space. Numerical examples were given to investigate the influence of different parameters on cuttings’ transport behavior, and the elliptical drillpipe was compared with the circular drillpipe. The annular cuttings concentration, annular pressure drop, and hole cleaning efficiency were evaluated. The numerical results clarify the potential of the elliptical drillpipe to enhance the hole cleaning efficiency without significantly increasing the annular pressure drop. Due to the swirl flow and secondary flow caused by the rotation of the curvature wall, the swaying phenomenon of drill cuttings’ distribution along the rotation direction of drillpipe was observed and enhanced the cuttings transport ability. Using the elliptical drillpipe as a joint-type tool can improve hole cleaning performance. Under the optimum conditions applied in this study, the hole cleaning efficiency increased by nearly 18%.

Efficiency of cold atmospheric plasma, cleaning powders and their combination for biofilm removal on two different titanium implant surfaces

Objectives Biofilm removal is the decisive factor for the control of peri-implantitis. Cold atmospheric pressure plasma (CAP) can become an effective aid due to its ability to destroy and to inactivate bacterial biofilm residues. This study evaluated the cleaning efficiency of CAP, and air-polishing with glycine (APG) or erythritol (APE) containing powders alone or in combination with CAP (APG + CAP, APE + CAP) on sandblasted/acid etched, and anodised titanium implant surface. Materials and methods On respective titanium discs, a 7-day ex vivo human biofilm was grown. Afterwards, the samples were treated with CAP, APG, APE, APG + CAP, and APE + CAP. Sterile and untreated biofilm discs were used for verification. Directly after treatment and after 5 days of incubation in medium at 37 °C, samples were prepared for examination by fluorescence microscopy. The relative biofilm fluorescence was measured for quantitative analyses. Results Air-polishing with or without CAP removed biofilms effectively. The combination of air-polishing with CAP showed the best cleaning results compared to single treatments, even on day 5. Immediately after treatment, APE + CAP showed insignificant higher cleansing efficiency than APG + CAP. Conclusions CAP supports mechanical cleansing and disinfection to remove and inactivate microbial biofilm on implant surfaces significantly. Here, the type of the powder was not important. The highest cleansing results were obtained on sandblasted/etched surfaces. Clinical relevance. Microbial residuals impede wound healing and re-osseointegration after peri-implantitis treatment. Air-polishing treatment removes biofilms very effectively, but not completely. In combination with CAP, microbial free surfaces can be achieved. The tested treatment regime offers an advantage during treatment of peri-implantitis.

Recent Patents on Petroleum Pipe Inspection Gauge in China

Background: With a great growing demand for petroleum, the amount of petroleum pipe is also increasing, and petroleum pipe blockage has become a severe problem in China. It is necessary to clean and inspect the petroleum pipe regularly. But the current petroleum pipe in-spection gauge can very easily block the petroleum pipe ,while the cleaning efficiency is poor. Therefore, the anti-blocking capacity and high-efficiency cleaning ability of the petroleum pipe inspection gauge has been paid more and more attention. Objective: By analyzing and discussing the patents of petroleum pipe inspection gauges in China in recent years, the future design of petro-leum pipe inspection gauge has been provided and some valuable conclusions have been summarized to solve the current problems of pipe inspection gauge. Methods: This paper studied and compared various representative patents relevant to the petroleum pipe inspection gauge. Results: By summarizing a large number of patents about petroleum pipe inspection gauges in China, the anti-blocking capacity or cleaning efficiency of those patents are analyzed and compared, and the further development tendency of petroleum pipe inspection gauges has been discussed. Conclusion: The problems of easy blocking for petroleum pipe inspection gauge and poor cleaning efficiency are still exist. It is still the main development trend for the study on anti-blocking capacity and the improvement of cleaning efficiency. The future work can be focused on pigging technical cooperation, new materials, power source and intelligent control.

The Numerical Modeling of Gas Movement in a Single Inlet New Generation Multi-Channel Cyclone Separator

The work of traditional cyclones is based on the separation of solid particles using only the centrifugal forces. Therefore, they do not demonstrate high gas-cleaning efficiency, particularly in the cases where gas flows are polluted with fine solid particles (about 20 µm in diameter). The key feature of a new-generation multi-channel cyclone separator’s structure is that its symmetrical upgraded curved elements, with openings cut with their plates bent outwards, make channels for the continuous movement of the gas flows from the inflow opening to the central axis. The smoke flue of the vertical gas outflow is located near the cover of the separating chamber. The present work is aimed at studying the applicability of two various viscosity models and their modified versions to simulate aerodynamic processes in an innovative design for a multi-channel cyclone separator with a single inflow, using the computational fluid dynamics. The research results obtained in the numerical simulation are compared to the experimental results obtained using a physical model. The main purpose of this study is to provide information on how the new design for the multi-channel cyclone affects the distribution of gas flow in the cyclone’s channels. The modified viscosity models, k-ε and k-ω, and computational meshes with various levels of detailed elaboration were analyzed. The developed numerical models of a single-inlet multi-channel cyclone separator allow the researchers to describe its advantages and possible methods of improving its new structure. The developed models can be used for simulating the fluid cleaning phenomenon in the improved fourth-channel cyclone separator and to optimize the whole research process.

Study on the improvement of the device for cleaning low-grade cotton with high- moisture

This article analyzes the importance of the process of ginning cotton with high pollution before ginning, the operation of the ginning device before ginning, the impact of the device nodes with the raw cotton. At the same time, the cleaning efficiency of the machine in the cleaning equipment from small and large contaminants, the basic control developments and calculation processes in the selection of the technological parameters of the cleaners are considered. It was suggested and analyzed that before the cotton was ginned, the cleaning device should be replaced with cone-tipped piles and a new belt extension to remove impurities instead of fine-grained drum piles. The impact strength and impact of the proposed conical-tipped pile drums on cotton have been studied.

Theoretical study of the impact aimed at improving the efficiency of fiber cleaning

Since cotton cleaning in Uzbekistan is carried out mainly manually, this paper discusses the methods and technologies established in the process of cleaning cotton and fiber. The process of fiber cleaning is one of the important processes that complete the technological process of cotton processing, given that the quality of fiber largely depends on the efficiency of this process, the research work on the mechanization of the type of collection and improving the efficiency of its cleaning is analyzed. In order to improve the efficiency of cleaning cotton collected on the machine, information is provided on the need to improve the equipment for cleaning fiber used in cotton gins. The research results are based on the need to replace a special structural device that guides the fiber to the correct tooth of the first sawtooth cylinder located on two drum cleaning plants. New fiber-cleaning equipment was installed in the Jizzakh regional JSC “Zarbdor cotton cleaning» and experimental tests were conducted in production conditions. In addition, the process of changing the pressure, density and speeds in the furnace and the effect of their cleaning efficiency has been modeled and theoretically analyzed, when the efficiency of cleaning the cotton fiber flow using a column system allows changing the raw material from 4 mm to 15 mm based on the device. By results of the conducted analysis it was shown that the increase of efficiency of purification depends on the device attached to the saw teeth, factor of the taxation of the distribution coefficient B and p 0 efficiency factor of increasing the initial pressure and coefficient of efficiency savings from the analysis of graphs, which present graphs of the distribution depending on the type of saw teeth. Based on the results of the research, recommendations are given for the widespread introduction of fiber cleaning equipment installed at enterprises of primary cotton processing, with the installation of a special structural guide device.

Hibiscus sabdariffa L. calyces’ and argon DBD plasma: potential eco-friendly cleaners for fire-damaged silver gelatin prints

Purpose This paper aims at examining the potentiality of using Hibiscus sabdariffa L. calyces’ (Hs) aqueous extract to remove soot stains from the surface of fire-damaged silver gelatin prints. It further studies the cleaning efficiency and impact of both a contact method and a noncontact method with argon dielectric barrier discharge plasma (DBD Ar. plasma) on the different properties of silver gelatin prints. Accordingly, it prompts using economic, eco-friendly materials and methods in the photograph conservation field. Design/methodology/approach To achieve the aims of this paper, four silver gelatin prints were stained with soot and treated with the (Hs) aqueous extract as a contact method and DBD Ar. plasma combined with the aqueous extract as a noncontact method. The assessment was carried out using digital microscopy, atomic force microscopy and spectrophotometer to study the efficiency of the tested treatments and their impact on the surface of the photographs. FTIR was used to monitor the state of the binder after cleaning. Furthermore, the pH and the mechanical properties were measured. Findings The contact method resulted in lower concentrations of (Hs) extract that efficiently cleaned the surface without causing any stains or damage to the treated photographs. The noncontact method (plasma with an aqueous extract) proved to be less effective in cleaning and made the binder more susceptible to deterioration. Originality/value This paper reveals the success of (Hs) aqueous extract in cleaning soot on vulnerable photographs’ surfaces.