Use of evaporative coolers for close circuiting of the electroplating process

Mapping Intimacies ◽

10.51415/10321/685 ◽

2011 ◽

Author(s):

◽

Megashnee Munsamy

Keyword(s):

Waste Water ◽

Cooling Tower ◽

Ambient Air ◽

Equilibrium Temperature ◽

Closed Circuit ◽

System Model ◽

Water Evaporation ◽

Plating Bath ◽

Electroplating Process ◽

Evaporative Cooling Tower

The South African electroplating industry generates large volumes of hazardous waste water that has to be treated prior to disposal. The main source of this waste water has been the rinse system. Conventional end-ofpipe waste water treatment technologies do not meet municipality standards. The use of technologies such as membranes, reverse osmosis and ion exchange are impractical, mainly due to their cost and technical requirements. This study identified source point reduction technologies, close circuiting of the electroplating process, specific to the rinse system as a key development. Specifically the application of a low flow counter current rinse system for the recovery of the rinse water in the plating bath was selected. However, the recovery of the rinse tank water was impeded by the low rates of evaporation from the plating bath, which was especially prevalent in the low temperature operating plating baths. This master’s study proposes the use of an induced draft evaporative cooling tower for facilitation of evaporation in the plating bath. For total recovery of the rinse tank water, the rate of evaporation from the plating bath has to be equivalent to the rinse tanks make up water requirements. A closed circuit plating system mathematical model was developed for the determination of the mass evaporated from the plating bath and the cooling tower for a specified time and the equilibrium temperature of the plating bath and the cooling tower. The key criteria in the development of the closed circuit plating system model was the requirement of minimum solution specific data as this information is not readily available. The closed circuit plating system model was categorised into the unsteady state and steady state temperature regions and was developed for the condition of water evaporation only. The closed circuit plating system model was programmed into Matlab and verified. The key factors affecting the performance of the closed circuit plating system were identified as the plating solution composition and operational temperature, ambient air temperature, air flow rate and cooling tower iv packing surface area. Each of these factors was individually and simultaneously varied to determine their sensitivity on the rate of water evaporation and the equilibrium temperature of the plating bath and cooling tower. The results indicated that the upper limit plating solution operational temperature, high air flow rates, low ambient air temperature and large packing surface area provided the greatest water evaporation rates and the largest temperature drop across the height of the cooling tower in the unsteady state temperature region. The final equilibrium temperature of the plating bath and the cooling tower is dependent on the ambient air temperature. The only exception is that at low ambient air temperatures the rate of water evaporation from the steady state temperature region is lower than that at higher ambient air temperatures. Thus the model will enable the electroplater to identify the optimum operating conditions for close circuiting of the electroplating process. It is recommended that the model be validated against practical data either by the construction of a laboratory scale induced draft evaporative cooling tower or by the application of the induced draft evaporative cooling tower in an electroplating facility.

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Determination of Volumetric Heat and Mass Transfer Coefficients in Filling Unit of Evaporative Cooling Tower

2020 International Multi-Conference on Industrial Engineering and Modern Technologies (FarEastCon) ◽

10.1109/fareastcon50210.2020.9271292 ◽

2020 ◽

Author(s):

I. Madyshev ◽

A. Dmitriev ◽

V. Kharkov

Keyword(s):

Mass Transfer ◽

Heat And Mass Transfer ◽

Cooling Tower ◽

Evaporative Cooling ◽

Transfer Coefficients ◽

Mass Transfer Coefficients ◽

Evaporative Cooling Tower

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Improving Natural Draft Cooling Tower Performance With Heat Injection

2002 International Joint Power Generation Conference ◽

10.1115/ijpgc2002-26028 ◽

2002 ◽

Cited By ~ 1

Author(s):

Eugene Grindle ◽

John Cooper ◽

Roger Lawson

Keyword(s):

Water Temperature ◽

Computer Model ◽

Cooling Tower ◽

Ambient Air ◽

Combined Cycle ◽

Steam Boiler ◽

Natural Draft ◽

Circulating Water ◽

Vapor Stream ◽

Heat Injection

This paper presents an assessment of heat injection as a means of improving natural draft cooling tower performance. The concept involves injecting heat into the cooling tower exit air/vapor stream immediately above the drift eliminators in order to increase the difference between the density of the exit air/vapor stream and the ambient air. The density difference between the air/vapor in the cooling tower stack and the ambient air is the engine that drives airflow through the cooling tower. The enhancement of the airflow through the cooling tower (the natural draft) results in more evaporation and thus lowers the circulating water temperature. Because the heat is injected above the drift eliminators, it does not heat the circulating water. To evaluate the cooling tower performance improvement as a function of heat injection rate, a thermal/aerodynamic computer model of Entergy’s White Bluff 1 & 2 and Independence 1 & 2 (approximately 840 MW each) natural draft cooling towers was developed. The computer model demonstrated that very substantial reductions in cold water temperature (up to 7°F) are obtainable by the injection of heat. This paper also discusses a number of possible heat sources. Sources of heat covered include extraction steam, auxiliary steam, boiler blow-down, and waste heat from a combustion turbine. The latter source of heat would create a combined cycle unit with the combination taking place in the condensing part of the cycle (bottom of the cycle) instead of the steam portion of the cycle (top of the cycle).

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Controlling water evaporation through self-assembly

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1604134113 ◽

2016 ◽

Vol 113 (37) ◽

pp. 10275-10280 ◽

Cited By ~ 18

Author(s):

Kevin Roger ◽

Marianne Liebi ◽

Jimmy Heimdal ◽

Quoc Dat Pham ◽

Emma Sparr

Keyword(s):

Self Assembly ◽

Feedback Loop ◽

Ambient Air ◽

Underlying Mechanism ◽

Water Evaporation ◽

Air Humidity ◽

X Ray ◽

X Ray Scattering ◽

Composition And Structure ◽

Living Organisms

Water evaporation concerns all land-living organisms, as ambient air is dryer than their corresponding equilibrium humidity. Contrarily to plants, mammals are covered with a skin that not only hinders evaporation but also maintains its rate at a nearly constant value, independently of air humidity. Here, we show that simple amphiphiles/water systems reproduce this behavior, which suggests a common underlying mechanism originating from responding self-assembly structures. The composition and structure gradients arising from the evaporation process were characterized using optical microscopy, infrared microscopy, and small-angle X-ray scattering. We observed a thin and dry outer phase that responds to changes in air humidity by increasing its thickness as the air becomes dryer, which decreases its permeability to water, thus counterbalancing the increase in the evaporation driving force. This thin and dry outer phase therefore shields the systems from humidity variations. Such a feedback loop achieves a homeostatic regulation of water evaporation.

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Experimental analysis of heat and mass transfer phenomena in a direct contact evaporative cooling tower

Energy Conversion and Management ◽

10.1016/j.enconman.2009.02.002 ◽

2009 ◽

Vol 50 (6) ◽

pp. 1610-1617 ◽

Cited By ~ 56

Author(s):

M. Lemouari ◽

M. Boumaza ◽

A. Kaabi

Keyword(s):

Mass Transfer ◽

Heat And Mass Transfer ◽

Experimental Analysis ◽

Direct Contact ◽

Cooling Tower ◽

Evaporative Cooling ◽

Evaporative Cooling Tower

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2-Mercaptobenzimidazole, 2-Mercaptobenzothiazole, and Thioglycolic Acid in an Electroless Nickel-Plating Bath

Journal of Chemistry ◽

10.1155/2015/872516 ◽

2015 ◽

Vol 2015 ◽

pp. 1-11

Author(s):

Ahmet Ozan Gezerman ◽

Burcu Didem Çorbacıoğlu

Keyword(s):

Waste Water ◽

Electroless Plating ◽

Thioglycolic Acid ◽

Electroless Nickel ◽

Optical Microscope ◽

Electroless Nickel Plating ◽

Nickel Plating ◽

Plating Bath ◽

Bath Solution ◽

Microscope Images

The use of three different materials, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, and thioglycolic acid, was investigated to improve the performance of electroless nickel-plating baths. By changing the concentrations of these materials, sample plates were coated. Optical microscope images were obtained by selecting representative coated plates. From the results of the investigations, the effects of these materials on electroless nickel plating were observed, and the most appropriate amounts of these materials for nickel plating were determined. Moreover, the nickel plating speed observed with the bath solution containing 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, and thioglycolic acid is higher than that in the case of traditional electroless plating baths, but the nickel consumption amount in the former case is lower. In order to minimize the waste water generated from electroless nickel-plating baths, we determined the lowest amounts of the chemicals that can be used for the concentrations reported in the literature.

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PHOTOCATALYTIC ACTIVITY UNDER VISIBLE LIGHT REGION OF Ca-MODIFIED TiO2NP FILMS PREPARED BY SPARKING OFF Ca-ELECTROPLATED Ti TIPS

Surface Review and Letters ◽

10.1142/s0218625x18400024 ◽

2018 ◽

Vol 25 (Supp01) ◽

pp. 1840002 ◽

Cited By ~ 2

Author(s):

NIDCHAMON JUMRUS ◽

ARISARA PANTHAWAN ◽

TEWASIN KUMPIKA ◽

WATTIKON SROILA ◽

EKKAPONG KANTARAK ◽

...

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Quartz Substrate ◽

Ambient Air ◽

Visible Light Region ◽

Structural And Optical Properties ◽

Uniform Size ◽

Light Region ◽

Vis Spectroscopy ◽

Electroplating Process

In this work, calcium (Ca)-modified titanium dioxide (TiO2) nanoparticulate (NP) films were successfully prepared using sparking off Ca-electroplated Ti tips. Aqueous solution of calcium carbonate (CaCO3) was used as electrolyte in the electroplating process. The experiment was carried out using electric current of 0.02[Formula: see text]mA applied to titanium electrodes for 10[Formula: see text]min. The NP films with small and uniform size were deposited on quartz substrate using the sparking process with a high DC voltage of 4[Formula: see text]kV in ambient air. The as-deposited NP films were then annealed at 800∘C, 900∘C and 1000∘C for 3[Formula: see text]h under atmospheric pressure to improve their crystallinity. Morphology, structural and optical properties of the NP films were characterized by SEM, XRD, Raman, XPS and UV-Vis spectroscopy. The effects of annealing temperature on the properties of the as-deposited and annealed NP films were reported. Furthermore, photocatalytic activity against 10 [Formula: see text]M of methylene blue (MB) under visible light region will be discussed.

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A novel evaporative cooling tower constructed from an inflatable fabric duct

Science and Technology for the Built Environment ◽

10.1080/23744731.2018.1460146 ◽

2018 ◽

Vol 24 (8) ◽

pp. 908-918 ◽

Cited By ~ 2

Author(s):

Steven Duong ◽

Robert Craven ◽

Steve Garner ◽

Stephen Idem

Keyword(s):

Cooling Tower ◽

Evaporative Cooling ◽

Evaporative Cooling Tower

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Study of Optimum Conditions for Zinc Plating on Mild Steel

International Journal of Engineering Research in Africa ◽

10.4028/www.scientific.net/jera.2.31 ◽

2010 ◽

Vol 2 ◽

pp. 31-39 ◽

Cited By ~ 10

Author(s):

Muhammed Olawale Hakeem Amuda ◽

W. Subair ◽

O.W. Obitayo

Keyword(s):

Mild Steel ◽

Process Parameters ◽

Current Density ◽

Optimum Conditions ◽

Plating Bath ◽

Zinc Plating ◽

Electroplating Process ◽

Deposition Conditions

The effect of some process parameters on the weight of zinc deposited on mild steel in a typical electroplating process is reported. The study indicates that the weight of zinc deposited on mild steel during the process is affected by plating temperature, current density, plating bath pH and plating time. The study established that optimum deposition of zinc is achieved at plating temperature of 320C, plating bath pH of 4.4, current density 40mA/cm2 and plating time of 30 minutes. 8.7mg of zinc was deposited at optimum deposition conditions. The profile of the zinc deposited decreases after optimum deposition is attained.

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Fast Copper Plating Process for Through Silicon Via (TSV) Filling

Volume 11: Nano and Micro Materials, Devices and Systems; Microsystems Integration ◽

10.1115/imece2011-64782 ◽

2011 ◽

Cited By ~ 5

Author(s):

Su Wang ◽

S. W. Ricky Lee

Keyword(s):

Integrated Circuits ◽

Cross Sections ◽

Three Dimensional ◽

Optical Microscope ◽

Copper Plating ◽

Ray Method ◽

Plating Bath ◽

Bottom Up ◽

Electroplating Process ◽

Filling Mechanism

There is an increasing demand for electronic devices with smaller sizes, higher performance and increased functionality. The development of vertical interconnects or through silicon vias (TSV) may be one of the most promising approaches to provide the three-dimensional (3D) integration of integrated circuits (IC). It is possible to improve the system’s performance with shorter RC delay, shorter signal paths and less power consumption. Electroplating process is one of the major contributors to the cost of TSV. Thus, plating time is one of our major concerns in TSV applications. About 80% of the TSVs are filled with copper due to its high conductivity and wide applications in multilayer wiring. Even though the electroplating of copper for interconnections is well established for the copper damascene micro-fabrication process, it has been shown that the filling of TSVs with copper plating is a different situation due to the much larger dimensions of TSVs. Generally the filling mechanism consists of conformal plating and bottom up plating. A 100% bottom up filling is preferred for copper filling in TSV. A seam may exist in via if the majority of filling mechanism is conformal plating. Thus, the bottom up filling profile is one the critical points to achieve void free filling. In this study, the void free copper filling TSVs with diameter from 10–30 m and depth from 50–150 m will be investigated by copper electroplating. A near 100% bottom up plating formula was developed in order to achieve void free and seam free filling. Filling performance of this plating formula was evaluated by examining vertical cross-sections and top-down cross-section of the filled TSVs using optical microscope and X-ray method. Pretreatment process and relationship with diffusion time will be also studied with respect to the TSV plating process. The effect of concentration of copper, acid and additives will be optimized to achieve the desired bottom up plating process. The ultimate goal is to achieve TSV plating with shorter plating time and better consistency. Electroplating experiment was conducted with an industrial electroplating tool. Successful plating results are demonstrated with optimized plating bath and plating mechanism. The void free and seam free copper deposition results are shown with minimized overburden. The time taken for the plating process is also greatly reduced with this near 100% bottom up plating formula. The benefits of this novel plating mechanism will be discussed in detail in this paper.

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