• Journal of the Korean GEO-environmental Society
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• v.12 no.11
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• pp.59-64
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• 2011

Clogging in drainage pipe is one of the important problems, so it needs a remedy urgently. Recently, scale in drainage pipe is removed by water jet cleaning and other treatment. But these treatments need much cost and regular management. The principal component of scale in drainage pipe is $CaCO_{3}$. It was observed the setting of $CaCO_{3}$ by some kind of analysis such as SEM, XRD, visual and weight measuring analysis to solve these problems and prevent setting formation in drainage pipe. As a result, in case of magnetic, particle shape of $CaCO_{3}$ is changed Aragonite from Calcite. Also in case of Quantum Stick, the amount of scale is reduced by expert inspector's result. As a whole, Magnetic treatment and Quantum Stick have the effect for protecting of scale precipitation.

• Journal of Korean Society on Water Environment
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• v.18 no.3
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• pp.303-312
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• 2002

Polly-pigs technique was developed to remove internal rusts and scales from service pipes in the building by using Polly-pigs that were used as various applications in conventional plant pipelines. Results of cleaning experiments on 15mm GSP(Galvanic Steel Pipe) showed that hydraulic cross sectional area was more increased from 3.5% to 15.4% for straight part or elbow parts of several test pieces. Results of optical analysis also showed that rust and scale removed mostly by KDP series(only consisted of Polyurethane) were outside red colored scale ($Fe_2O_3{\cdot}H_2O$), and there was a limitation to the removal of black colored scale($Fe_2O{\cdot}nH_2O$) that was below red colored scale. But it was evaluated that KDPS series coated fine sand with KDP series could remove not only red colored scale but also black colored scale and more increase hydraulic cross sectional areas of 15mm GSP old service pipes from 13.0% to 17.9%. After KDPS series cleaning, hydraulic cross sectional areas of them were recovered from 95.9% to 99.5%. Turning force of Polly-pigs was largely improved by the effect of Helical guide vane(Cleaning v/v) and Rotating wing(Pigs), and the number of pig rotating also more increased sixteen times compared with conventional cleaning system without Helical guide vane and Rotating wing. After KDPC series cleaning of 100mm GSP old service pipes that hydraulic cross sectional areas were 90%, hydraulic cross sectional areas were almost recovered perfectly like new service pipes. Additionally pressure necessary to run Polly-pigs m 100mm GSP was lower and cleaning efficiency also was higher than 15mm GSP cleaning. Therefore it was thought that as the diameter of pipe was more increased, pressure necessary to clean service pipes was more decreased and cleaning efficiency was more increased in Polly-pigs cleaning.

• Journal of Korea Water Resources Association
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• v.32 no.4
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• pp.469-478
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• 1999

Explicit equations of minimum velocity, energy slope and pipe diameter are developed to ensure the cleaning of sewerage pipes. The equations of power form are employed for the estimation of critical shear stress of sediment particles and the friction factor of commercial pipes. They are all based on the existing laboratory data. Several cases are tested to check the values suggested in the manual, using the equations developed in the present study.

• Journal of Korea Water Resources Association
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• v.53 no.11
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• pp.1015-1024
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• 2020

Recently, water pollution accidents have continued to occur in pipelines such as red water Incheon and Seoul. In order to recognize this water quality problem, it is necessary to install a water quality sensor in an appropriate location and measure it in advance to detect or block the water supply to the water faucet of the shelter. However, there are limitations, such as maintenance costs, to installing multiple water meters in all pipelines. Therefore, this study proposed a methodology for determining and prioritizing the installation location of flow-based water quality sensor for the recognition of water quality problems in pipelines. We applied the proposed procedure to the pipe break scenario. The results of the determination of the location of the water quality sensor were presented by applying it to the pipe network that actually operates the emergency pipe in Korea. The result of the decision showed that in the event of abnormal situation caused by the destruction of individual pipes, the flow rate of the pipes around the aqueduct and the tank may change rapidly, resulting in water quality accidents caused by turbidity. In the future, it is expected that the water quality monitoring point selection method, such as establishing an external pipe operation plan for pipe cleaning, will utilize the procedure for determining the location of the water quality sensor according to the velocity.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.5
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• pp.1-7
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• 2015

Cleaning by injecting dry ice and water is a generally adopted trend these days to clean molds (injection, diecasting foundry, press, rubber mold, etc). This cleaning method is performed manually, or by installing multiple high pressure spray nozzles. We have manufactured a turbine cleaning module device that is able to clean diecasting modules at any position and angle in the space by mounting an articulated robot instead of the existing pipe type injection nozzle, to minimize lead time and enhance working yield of the cleaning process. In this paper, we analyzed process factors that are required to design the turbine module by reviewing number of revolution, and results according to different blade angles and thicknesses of the mold release injection turbine module, using computational fiuid dynamics (CFD).

• Journal of Korean Society of Water and Wastewater
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• v.28 no.4
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• pp.441-451
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• 2014

The flushing is important to maintain good water quality in water main. It is a technique of using water velocity to remove sediments in water distribution system. The variety of water quality problems can occur in a distribution system, so too can a variety of benefits be gained by system flushing. In order to effectively perform the flushing, the contaminants to be removed to set up and it can be solved, it is necessary to ensure the proper flow rate. In this study, the removal of contaminants present in the inner water pipe attached loose deposits such as fine particles of granular activated carbon, sand and iron corrosion product sought to derive flow rates. Thus, the constant observation of using pilot plant scale water distribution plant for the movement of floating characteristics of particles were assessed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.11
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• pp.789-796
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• 2007

It has been noted, in case of the apartments in collective form, the drainage noise from cleaning of toilet causes many problems in the basement and adjacent rooms, mainly hampering the pleasant housing environment. The problems are increasingly raised by civil complaints with the public offices. Therefore, if the drainage noise generates when wash out of toilet bowl is grasped how the characteristics change according to the sorts of drainpipe, it is considered that the establishment of an effective sound insulation countermeasure could be possible when a civil petition against the drainage noise of apartment house is submitted hereafter. On such viewpoint, this study measured and analyzed the characteristics of drainage noise per the type of drainage pipe, according to KS A ISO $1996-1{\sim}3$, with the horizontal branch pipe and riser pipes in the drainage noise experiment chamber which has the characteristics of the anechoic room. In the result, the pipe type with excellent noise reduction function. The result of this study is considered to become available as fundamental data, to take actions on reduction of drainage noise of the ceiling piping method.

• Journal of Korea Water Resources Association
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• v.55 no.spc1
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• pp.1251-1260
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• 2022

Recently, due to the deterioration of watermains and the detachment of scale which is accumulated on the watermain surface, water quality accidents in a water supply network occur frequently. As scale accumulated on watermains is stabilized, it may not cause water quality accidents under the normal operating condition. However, due to water hammer or transient flow caused by the abrupt velocity and/or direction of flow change, it can be detached from the watermain surface resulting in water quality accidents. To prevent these kinds of water quality accidents, it is required to remove scale by watermain cleaning regularly. Many researches about flushing which is the most popular water cleaning method are focused on the desirable velocity criteria and the cleaning condition to accomplish the effect of flushing whereas less amount of research effort is given to develop a method to consider whether the desirable velocity for flushing can be obtained before flushing is performed. During flushing, the major and minor headloss is occurred when flushing water flows through a hydrant or drain valve. These headloss may slow down the velocity of flushing water so that it can reduce the flushing effect. Thus, in this study, we suggest a method to simulate the flow velocity of flushing water using "MinorLoss Coefficient" and "Emitter Coefficient" in EPANET. The suggested method is applied to a sample network and the water supply network of "A" city in Korea to compare the flushing effect between "flushing through a hydrant" and "flushing through a drain valve". In case of "flushing through a hydrant", if the hydraulic condition ocurring from a watermain pipe connecting to the inlet pipe of a hydrant to the outlet of a hydrant is not considered, the actual flowrate and velocity of a flow is less than the simulated flowrate and velocity of a flow. In case of "flushing through a drain valve", the flushing velocity and flowrate can be easily simulated and the difference between the simulated and the actual velocity and flowrate is not significant. Also, "flushing through a drain valve" is very effective to flushing a long-length pipe section because of its efficiency to obtain the flushing velocity. However, the number and location of a drain valve is limited compared to a hydrant so that "flushing through a drain valve" has a limited application in the field. For this reason, the engineer should consider various field conditions to come up with a proper flushing plan.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.465-470
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• 2006

An experimental investigation is carried out to study 2-phase vertically upward hydraulic transport of solid particles by water and non-Newtonian fluids in a slim hole concentric annulus with rotation of the inner cylinder. Rheology of particulate suspensions in viscoelastic fluids is of importance in many applications such as particle removal from surfaces, transport of proppants in fractured reservoir and cleaning of drilling holes, etc. In this study a clear acrylic pipe was used in order to observe the movement of solid particles. Annular fluid velocities varied from 0.2 m/s to 3.0 m/s. Pressure drops and average flow rate and particle rising velocity are measured. For both water and 0.2% CMC solutions, the higher the concentration of the solid particles is, the larger the pressure gradients become.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.369-372
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• 2008

An experimental study is carried out to study two-phase vertically upward hydraulic transport of solid particles by water in a vertical and inclined (0${\sim}$60 degree) concentric annulus with rotation of the inner cylinder. Rheology of particulate suspensions in shear-thinning fluids is of importance in many applications such as particle removal from surfaces, transport of proppants in fractured reservoir and cleaning of drilling holes, and so on. Annular fluid velocities varied from 0.2 m/s to 1.5 m/s for the actual drilling operational condition. Macroscopic behavior of solid particles, averaged flow rate, and particle rising velocity are observed. Main parameters considered in this study were radius ratio, inner-pipe rotary speed, fluid flow regime, and particle injection rate. For both water and CMC solutions, the higher the concentration of the solid particles is, the larger the pressure gradients become