The Enhancement of Pre-Storage Filtration Efficiency for the Rainwater Harvesting System in Malaysia

A conventional design of rainwater harvesting system collects and directs the rainwater through water piping from roof of building to the water storage. The filtration system which locates before the water tank storage and first flush bypass system is the main focus of the research. A filtration system consists of a control volume of filter compartment, filter screen (stainless steel mesh) and water piping that direct the water flow. The filtration efficiency of an existing filter “3P Volume Filter VF1” by industrial company is enhanced. A full scale filter design prototype with filter screen of 1000 μm stainless steel metal mesh is tested to compare with the original filter system design. Three types of water inlet setups are tested. Among the proposed water inlet setups, the 90° inlet setup with extension provides the best filtration rate per unit time, following by the 45° inlet setup. The 45° and 90° inlet setup has similar filtration efficiency at low to medium flow rate while 45° inlet setup has better efficiency at high flow rate. The filtration efficiency with the 90° inlet setup with extension is observed to maintain at highest value at medium to high flow rate. The overall filtration performance achieved by the 90° inlet setup with extension at low to high flow rate is between 34.1 to 35.7%.

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Effects of Water Flow Rate on Fatigue Life of Structural Steels Under Simulated BWR Environment

Volume 1: Codes and Standards ◽

10.1115/pvp2007-26423 ◽

2007 ◽

Cited By ~ 3

Author(s):

Akihiko Hirano ◽

Katsumi Sakaguchi ◽

Tetsuo Shoji

Keyword(s):

Stainless Steel ◽

Fatigue Life ◽

Water Flow ◽

Flow Rate ◽

Environmental Effect ◽

Water Flow Rate ◽

High Flow ◽

High Flow Rate ◽

Sulfur Concentration ◽

Type 304

Fatigue tests in simulated LWR environment of carbon and stainless steels were performed under high water flow rates between 7 to 10 m/s. For carbon steel, high flow rate of water clearly mitigated the environmental effect on the fatigue life at the high sulfur concentration of 0.016% which caused high environmental effect on a fatigue life. On the contrary, high flow rate of water slightly enhanced the environmental effect at the low sulfur concentration at or less than 0.008% which caused very low environmental effect. These results suggested that the environmental fatigue life under various flow rate conditions should be determined by the combination between the mitigating effect caused by flushing of the severe local environment and the enhancing effect caused by increase in corrosion potential. Low alloy steel showed the similar behavior as carbon steel. For stainless steel, flow rate had little effect on the fatigue life of type 316NG stainless steel. It suggested that there was no role of water flushing. For type 304 and 304L stainless steel, fatigue life has a tendency to decrease with increase in water flow rate. Fatigue lives of type 304 stainless steel under high flow rate of 7 to 10 m/s were shorter than those predicted by proposed fatigue life prediction equation by the Japanese EFT committee. This effect should be considered in an evaluation of environmental fatigue. No water flow effect was found in cast stainless steel.

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Experiment Study of High-Temperature and High-Flow Rate Naphthenic Acid Corrosion

ASME 2011 Pressure Vessels and Piping Conference: Volume 6, Parts A and B ◽

10.1115/pvp2011-57640 ◽

2011 ◽

Cited By ~ 1

Author(s):

Ke Jiang ◽

Xuedong Chen ◽

Tiecheng Yang ◽

Zongchuan Qin

Keyword(s):

Stainless Steel ◽

High Temperature ◽

Corrosion Rate ◽

Flow Rate ◽

Acid Corrosion ◽

Naphthenic Acid ◽

High Flow ◽

High Flow Rate ◽

Experimental Results ◽

Wall Turbulence

The corrosion behaviors of 321 and 316L austenitic stainless steel in high-temperature and high-flow rate naphthenic acid medium were investigated by pipe-flow and jet-impingement method. The influence of temperature and erosion angle on naphthenic acid corrosion resistance for stainless steel was analyzed. The results indicate that the naphthenic acid corrosion rate increased with increasing temperature and velocity. At the same temperature, the corrosion rate at 90° erosion angle is greater than that at 0°. The present experimental results are very close to those in API 581. Simulation results indicate that, where the mutation of flow direction occurs around the specimen, the near-wall turbulence intensities are very large by both experimental methods. Moreover, by comparing both the simulation and experimental results, it can be found that the naphthenic acid corrosion is very severe in areas of high turbulence.

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Effects of Water Flow Rate on Fatigue Life of Carbon and Stainless Steels in Simulated LWR Environment

Pressure Vessel and Piping Codes and Standards ◽

10.1115/pvp2004-2680 ◽

2004 ◽

Cited By ~ 2

Author(s):

Akihiko Hirano ◽

Michiyoshi Yamamoto ◽

Katsumi Sakaguchi ◽

Tetsuo Shoji

Keyword(s):

Stainless Steel ◽

Fatigue Life ◽

Water Flow ◽

Flow Rate ◽

Environmental Effect ◽

Corrosion Potential ◽

High Flow ◽

High Flow Rate ◽

Sulfur Concentration ◽

Rate Condition

Fatigue tests in simulated LWR environment of carbon and stainless steels were performed under high water flow rates between 7 to 10 m/s. For carbon steel, high flow rate of water clearly mitigated the environmental effect on a fatigue life at the high sulfur concentration of 0.016 wt% which caused high environmental effect on a fatigue life. On the contrary, high flow rate of water slightly enhanced the environmental effect at the low sulfur concentration at or less than 0.008 wt% which caused very low environmental effect. These results suggested that the environmental fatigue life under various flow rate conditions should be determined by the combination between the mitigating effect caused by flushing of locally severe environment and the enhancing effect caused by increase in corrosion potential. To understand those effects, effects of sulfur concentration on fatigue life for various DO condition were formulated. And corrosion potential under low and high flow rate condition was measured during the fatigue test. Environmental correction factor, Fen, which is the ratio of fatigue lives derived from the fatigue life at room temperature in air divided by that in water to be used for the fatigue life prediction at high flow rate condition was assumed based on the MITI guideline equation and considering the hypothetical fatigue life under sulfur free condition and high corrosion potential condition. This assumption was agreed very well with the test data. For stainless steel, flow rate had little effect on a fatigue life of type 316 stainless steel. It suggested that there was no role of water flushing. For type 304 stainless steel, fatigue life has a tendency to decrease with increase in water flow rate. Fatigue lives of type 304 stainless steel under high flow rate of 7 to 10 m/s were shorter than those predicted by MITI guideline equation. This effect should be considered in an evaluation of environmental fatigue.

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