Friday, October 5, 2012

Definition of NPSHr (required)

It is the energy in the liquid required to overcome the friction losses from the suction nozzle to the eye of the impeller without causing vaporization. It is a characteristic of the pump and is indicated on the pump's curve. It varies by design, size, and the operating conditions. It is determined by a lift test, producing a negative pressure in inches of mercury and converted into feet of required NPSH.

An easy way to understand NPSHr is to call it the minimum suction pressure I necessary to keep the pumped fluid in a liquid state.

According to the Standards of the Hydraulic Institute, a suction lift test is performed on the pump and the pressure in the suction vessel is lowered to the point where the pump suffers a 3% loss in total head. This point is called the NPSHr of the pump. Some pump manufacturers perform a similar test by closing a suction valve on a test pump and other manufacturers lower the suction elevation. Know and Understand Centrifugal Pumps

Wednesday, October 3, 2012

Basic Pump Principles (Part 2)

Pressure measurement

Force (F) is equal to Pressure (P) multiplied by the Area (A):

F = P x A.

Pressure is equal to the Force divided by the Area:

P = F/A

If we apply pressure to the surface of a liquid, the pressure is transmitted uniformly in all directions across the surface and even through the liquid to the walls and bottom of the vessel containing the liquid (Pascal’s Law). This is expressed as pounds per square inch (lbs/in2, or psi), or kilograms per square centimeter (k/cm2).

Atmospheric pressure (ATM)

Atmospheric pressure (ATM) is the force exerted by the weight of the atmosphere on a unit of area. ATM = 14.7 psia at sea level. As elevation rises above sea level, the atmospheric pressure is less.

Absolute pressure (psia)

Absolute pressure is the pressure measured from a zero pressure reference. Absolute pressure is 14.7 psia at sea level. Compound pressure gauges record absolute pressure.

Monday, October 1, 2012

Basic Pump Principles

Pumps are used to transfer liquids from low-pressure zones to highpressure zones:

Without a pump in this system, the liquid would move in the opposite direction because of the pressure differential. Pumps are also used to move liquids from a low elevation into a higher elevation, and to move liquids from one place to another. Pumps are also used to accelerate liquids through pipes.

Sunday, September 30, 2012

Approach to Heat-Exchanger Design

The proper use of basic heat-transfer knowledge in the design of practical heat-transfer equipment is an art. Designers must be constantly aware of the differences between the idealized conditions for and under which the basic knowledge was obtained and the real conditions of the mechanical expression of their design and its environment. The result must satisfy process and operational requirements (such as availability, flexibility, and maintainability) and do so economically. An important part of any design process is to consider and offset the consequences of error in the basic knowledge, in its subsequent incorporation into a design method, in the translation of design into equipment, or in the operation of the equipment and the process. Heat-exchanger design is not a highly accurate art under the best of conditions.

Thursday, September 27, 2012

Water Treatment in General

Water must have eye appeal and taste appeal before we will drink it with much relish. Instinctively we draw back from the idea of drinking dirty, smelly water. Actually far more important to our well-being is whether or not a water is safe to drink. If it holds &sease bacteria, regardless of its clarity and sparkle, we should avoid it. Let's consider these two highly important aspects of water: potability and palatability.

Regardless of any other factors, water piped into the home must be potable. To be potable, it should be completely free of disease organisms. Water is the breeding ground for an almost unbelievably large variety of organisms. Water does not produce these organisms. It merely is an ideal medium in whch they can grow. These organisms gain entry into water through a variety of sources. They enter from natural causes, surface drainage and sewage. Many of the organisms in water are harmless. In fact, they are extremely beneficial to man. Others have a wide nuisance value and still others are the source of disease. In general, we are primarily concerned here with organisms which are potential disease-producers. These are of five types: bacteria, protozoa, worms, viruses, fungi. The presence of certain organisms of these various types can lead to such infectious diseases as typhoid fever, dysentery, cholera, jaundice, hepatitis, undulant fever and tularaemia.

There are other diseases as well, which spread through d r i i g unsafe water. Tremendous strides have been made in the control of these diseases within recent years. Much of the credit must go to sanitary engineers for their careful, consistent control of public water supplies. Biologically, there are two major classifications for our purposes. We can classify water organisms either as members of the plant or animal kingdoms.The following ways are the natural ways, in which water is purified: Bacteria and algae consume organic waste; Micro-organisms devour bacteria and algae; Oxidation renders organic matter harmless; Ultra-violet rays of
sun have germicidal effects. 

Under the broad heading of plant forms, we can classify the following:

Tuesday, September 25, 2012

Energy Intensive Treatment Technologies

Ozone is used extensively in Europe to purify water. Ozone, a molecule composed of 3 atoms of oxygen rather than two, is formed by exposing air or oxygen to a high voltage electric arc. Ozone is much more effective as a disinfectant than chlorine, but no residual levels of disinfectant exist after ozone turns back into O2. (One source quotes a half life of only 120 minutes in distilled water at 20 "C). Ozone is expected to see increased use in the U.S. as a way to avoid the production and formation of trihalomethanes, and while ozone does break down organic molecules, sometimes this can be a disadvantage as ozone treatment can produce higher levels of smaller molecules that provide an energy source for microorganisms. If no residual disinfectant is present (as would happen if ozone were used as the only treatment method), these microorganisms will cause the water quality to deteriorate in storage. Ozone also changes the surface charges of dissolved organics and colloidially suspended particles. This causes microflocculation of the dissolved organics and coagulation of the colloidal particles.

Thursday, September 20, 2012

Introducing Chemical Treatment

Chlorine is familiar to most people as it is used to treat virtually all municipal water systems in the United States. Chlorine has a number of problems when used for field treatment of water. When chlorine reacts with organic material, it attaches itself to nitrogen containing compounds (ammonium ions and amino acids), leaving less free chlorine to continue disinfection. Carcinogenic trihalomethanes are also produced, though this is only a problem with long-term exposure. Trihalomethanes can also be filtered out with a charcoal filter, though it is more efficient to use the same filter to remove organics before the water is chlorinated. Unless free chlorine is measured, disinfection can not be guaranteed with moderate doses of chlorine. One solution is superchlorination, the addition of far more chlorine than is needed. This must again be filtered through activated charcoal to remove the large amounts of chlorine, or hydrogen peroxide can be added to drive the chlorine off. Either way there is no residual chlorine left to prevent recontamination. This isn't a problem, if the water is to be used at once.

Chlorine is sensitive to both the pH and temperature of the treated water. Temperature slows the reaction for any chemical treatment, but chlorine treatment is particularly susceptible to variations in the pH as at lower pHs, hypochlorous acid is formed, while at higher pHs, it will tend to dissociate into hydrogen and chlorite ions, which are less effective as a disinfectant. As a result, chlorine effectiveness drops off when the pH is greater than 8.Ordinary household bleach (such as Clorox) in the U.S. contains 5.25 % sodium hypochlorite (NaOCL) and can be used to purify water if it contains no other active ingredients, scents, or colorings. Some small treatment plants in Africa produce their own sodium hypochlorite on site from the electrolysis of brine. Power demands range from 1.7 to 4 kwh per lb. of NaOCL. 2 to 3.5 lbs. of salt are needed for each pound of NaOCL. These units are fairly simple and are made in both the U.S. and the U.K. Another system, designed for China, where the suitable raw materials were mined or manufactured locally, used a reaction between salt, manganese dioxide, and sulfuric acid to produce chlorine gas. The gas was then allowed to react with slaked lime to produce a bleaching powder that could then be used to treat water. A heat source is required to speed the reaction up. Bleaching Powder (or Chlorinated Lime) is sometimes used at the industrial scale. Bleaching powder is 33-37% chlorine when produced, but losses its chlorine rapidly, particularly when exposed to air, light or moisture.

Saturday, September 15, 2012

Introducing The Physical Treatment Methods

The following technologies are among the most commonly used physical methods of purifying water:

Heat Treatment - Boiling is one way to purify water of all pathogens. Most experts feel that if the water reaches a rolling boil it is safe. A few still hold out for maintaining the boiling for some length of time, commonly 5 or 10 minutes, plus an extra minute for every l000 feet of elevation. One reason for the long period of boiling is to inactivate bacterial spores (which can survive boiling), but these spore are unlikely to be waterborne pathogens. Water can also be treated at below boiling temperatures, if contact time is increased. Commercial units are available for residential use, which treat 500 gals of water per day at an estimated cost of $1/1000 gallons for the energy. The process is similar to milk pasteurization, and holds the water at 161" F for 15 seconds. Heat exchangers recover most of the energy used to warm the water. Solar pasteurizers have also been built that can heat three gallons of water to 65 " C and hold the temperature for an hour. A higher temperature could be reached, if the device was rotated east to west during the day to follow the sunlight. Regardless of the method, heat treatment does not leave any form of residual to keep the water free of pathogens in storage.

Reverse Osmosis - Reverse osmosis forces water, under pressure, through a membrane that is impermeable to most contaminants. The membrane is somewhat better at rejecting salts than it is at rejecting non-ionized weak acids and bases and smaller organic molecules (molecular weight below 200). In the latter category are undissociated weak organic acids, amines, phenols, chlorinated hydrocarbons, some pesticides and low molecular weight alcohols. Larger organic molecules and all pathogens are rejected. Of course, it is possible to have a imperfection in the membrane that could allow molecules or whole pathogens to pass through. Using reverse osmosis to desalinate seawater requires considerable pressure (1000 psi) to operate. Reverse osmosis filters are available that will use normal municipal or private water pressure to remove contaminates from water. The water produced by reverse osmosis, like distilled water, will be close to pure H,O. Therefore mineral intake may need to be increased to compensate for the normal mineral content of water in much of the world.

Tuesday, September 11, 2012

The Clean Water Act

Drinking water standards are not the only regulations we need to comply with in the U.S. Today's Clean Water Act has its origins from the late 1940s. The original 1948 statute (Chapter 758; PL 845), the Water Pollution Control Act, authorized the Surgeon General of the Public Health Service, in cooperation with other federal, state, and local entities, to prepare comprehensive programs for eliminating or reducing the pollution of interstate waters and tributaries and improving the sanitary condition of surface and underground waters. Since 1948, the original statute has been amended extensively to authorize additional water quality programs, standards and procedures to govern allowable discharges, and funding for construction grants or general programs. Amendments in other years provided for continued authority to conduct program activities or administrative changes to related activities. This legislation was originally enacted as the Federal Water Pollution Control Act of 1972, and was amended in 1977 and renamed the Clean Water Act. It was
reauthorized in 1991.

The Clean Water Act strives to restore and maintain the chemical, physical, and biological integrity of the nation's water. The act sets up a system of water quality standards, discharge limitations, and permits. If a project may result in the placement of material into waters, a Corps of Engineers' Dredge and Fill Permit (Section 404) may be required. The permit also pertains to activities in wetlands and riparian areas. Certain Federal projects may be exempt from the requirements of Section 404, if the conditions set forth in section 404(r) are met. Before either a National Pollutant Discharge Elimination System (NPDES) (Section 402) or Section 404 permit can be issued, the applicant must obtain a Section 401 certification. This declaration states that any discharge complies with all applicable effluent limitations and water quality standards.

Saturday, September 8, 2012

The Drinking Water Standards (Part 2)

In spite of the multitudinous regulations and standards that an existing public water system must comply with, the principles of conventional water treatment process have not changed significantly over half a century. Whether a filter contains sand, anthracite, or both, slow or rapid rate, constant or declining rate, filtration is still filtration, sedimentation is still sedimentation, and disinfection is still disinfection. What has changed, however, are many tools that we now have in our engineering arsenal. For example, , a supervisory control and data acquisition (SCADA) system can provide operators and managers with accurate process controI variables and operation and maintenance records. In addition to being able to look at the various options on the computer screen, engineers can conduct pilot plant studies of the multiple variables inherent in water treatment plant design. Likewise, operators and managers can utilize an ongoing pilot plant facility to optimize chemical feed and develop important information needed for future expansion and upgrading.

Technology and ultimately equipment selection depends on the standards set by the regulations. Drinking water standards are regulations that EPA sets to control the level of contaminants in the nation's drinking water. These standards are part of the Safe Drinking Water Act's "multiple barrier" approach to drinking water protection, which includes assessing and protecting drinking water sources; protecting wells and collection systems; making sure water is treated by qualified operators; ensuring the integrity of distribution systems; and making information available to the public on the quality of their drinking water. With the involvement of EPA, states, tribes, drinking water utilities, communities and citizens, these multiple barriers ensure that tap water in the U.S. and territories is safe to drink. In most cases, EPA delegates responsibility for implementing drinking water standards to states and tribes. There are two categories of drinking water standards:

Wednesday, September 5, 2012

The Drinking Water Standards (Part 1)

When the objective of water treatment is to provide drinking water, then we need to select technologies that are not only the best available, but those that will meet local and national quality standards. The primary goals of a water treatment plant for over a century have remained practically the same: namely to produce water that is biologically and chemically safe, is appealing to the consumer, and is noncorrosive and nonscaling. Today, plant design has become very complex from discovery of seemingly innumerable chemical substances, the multiplying of regulations, and trying to satisfy more discriminating palates. In addition to the basics, designers must now keep in mind all manner of legal mandates, as well as public concerns and environmental considerations, to provide an initial prospective of water works engineering planning, design, and operation.

The growth of community water supply systems in the United States started in the early 1800s. By 1860, over 400, and by the turn of the century over 3000 major water systems had been built to serve major cities and towns. Many older plants were equipped with slow sand filters. In the mid 1890s, the Louisville Water Company introduced the technologies of coagulation with rapid sand filtration. 

The first application of chlorine in potable water was introduced in the 1830s for taste and odor control, at that time diseases were thought to be spread by odors. It was not until the 1890s and the advent of the germ theory of disease that the importance of disinfection in potable water was understood. Chlorination was first introduced on a practical scale in 1908 and then became a common practice.

Tuesday, September 4, 2012

What We Mean by Water Purification

When we refer to water purification, it makes little sense to discuss the subject without first identifying the contaminants that we wish to remove from water. Also, the source of the water is of importance. Our discussion at this point focuses on drinking water. Groundwater sources are of a particular concern, because there are many communities throughout the U.S. that rely on this form. The following are some of the major contaminants that are of concern in water purification applications, as applied to drinking water sources, derived from groundwater.

Heavy Metals - Heavy metals represent problems in terms of groundwater pollution. The best way to identify their presence is by a lab test of the water or by contacting county health departments. There are concerns of chronic exposure to low levels of heavy metals in drinking water.

Monday, September 3, 2012

An Overview of Water And Waste-Water Treatment

We may organize water treatment technologies into three general areas: Physical Methods, Chemical Methods, and Energy Intensive Methods. Physical methods of wastewater treatment represent a body of technologies that we refer largely to as solid-liquid separations techniques, of which filtration plays a dominant role. Filtration technology can be broken into two general categories - conventional and non-conventional. This technology is an integral component of drinking water and wastewater treatment applications. It is, however, but one unit process within a modern water treatment plant scheme, whereby there are a multitude of equipment and technology options to select from depending upon the ultimate goals of treatment. To understand the role of filtration, it is important to make distinctions not only with the other technologies employed in the cleaning and purification of industrial and municipal waters, but also with the objectives of different unit processes.

Chemical methods of treatment rely upon the chemical interactions of the contaminants we wish to remove from water, and the application of chemicals that either aid in the separation of contaminants from water, or assist in the destruction or neutralization of harmful effects associated with contaminants. Chemical treatment methods are applied both as stand-alone technologies, and as an integral part of the treatment process with physical methods. 

Among the energy intensive technologies, thermal methods have a dual role in water treatment applications. They can be applied as a means of sterilization, thus providing high quality drinking water, and/or these technologies can be applied to the processing of the solid wastes or sludge, generated from water treatment applications. In the latter cases, thermal methods can be applied in essentially the same manner as they are applied to conditioning water, namely to sterilize sludge contaminated with organic contaminants, and/or these technologies can be applied to volume reduction. Volume reduction is a key step in water treatment operations, because ultimately there is a tradeoff between polluted water and hazardous solid waste.

Sunday, September 2, 2012

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Lucky Luke Comic

Lucky Luke is a Franco-Belgian comics series created by Belgian cartoonist Maurice De Bevere, better known as Morris, and for one period written by René Goscinny. Set in the American Old West, it stars the titular character, Lucky Luke, the cowboy known to "shoot faster than his shadow". Along with The Adventures of Tintin and Asterix, Lucky Luke is one of the most popular and best-selling comic- ook series in continental Europe.[1] About half of the series' adventures have been translated into English. Lucky Luke comics have been translated into 23 languages, including many European languages, some African and Asian languages.

Both a tribute to the mythic Old West and an affectionate parody, the comics were created by the Belgian artist Morris who drew Lucky Luke from 1946 until his death in 2001. The first Lucky Luke adventure named Arizona 1880 appeared in the Almanach issue of the comics magazine Le Journal de Spirou on December 7, 1946.[2] After several years of solitary work on the strip, Morris began a collaboration with René Goscinny who became the series' writer for a period that is considered the golden age of the series. This started with the story Des rails sur la Prairie published on August 25, 1955 in Spirou.[3] Ending a long run of serial publications in Spirou, the series shifted to Goscinny's magazine Pilote in 1967 with the story La Diligence, subsequently leaving publisher Dupuis for Dargaud.

Friday, August 31, 2012

Gas Chromatography/Mass Spectroscopy (2)


Material Identification - The first result from the compiled data is a total-ion chromatogram (TIC), which is a plot of the total mass eluting from the GC and detected by MS as a function of time. Each
peak or band in the chromatogram represents a discrete chemical compound, or a mixture of compounds with identical retention times. The retention times in the chromatogram provide the first
indication of the sample constituents. More specific identification of the compound(s) for each band can then be made from the mass spectrum corresponding to the band. Compounds are identified from the mass spectrum by their unique ion fragmentation patterns. This compound identification analysis is performed by a computerized comparison of the mass spectra for the sample with spectra library for known compounds.

Quantitation - The analysis results can be quantified using the data from the chromatogram. The area under each peak in the chromatogram is proportional to the concentration of the compounds represented by that peak. The concentration for each compound in the sample is calculated from a standard curve of known concentrations established for that compound. The analysis sensitivity can be as low as a few nanograms.

Gas Chromatography/Mass Spectroscopy (1)


Gas chromatography / mass spectrometry (GC/MS) is the marriage of two analytical methods into a versatile technique for the identification of complex volatile materials. Gas chromatography (GC) effectively separates the different constituents of the sample for subsequent analysis and identification by mass spectrometry (MS).

The chromatographic separation relies on the interaction of the sample with a mobile phase and a stationary phase within the GC instrument column. The sample is carried through the column by the mobile phase, typically an inert gas. However, the sample is slowed in its travel through the column as the sample molecules repeatedly adsorb and desorb from the stationary phase in the column. The affinity of a particular molecule for the stationary phase determines the retention time of that constituent in the column. The molecules for each component of the sample will travel through the column at nearly the same rate and exit (elute) from the column within a narrow time band that is specific to that component. Thus, compounds with different retention times in the column are physically separated for presentation to a detector and analyzer.

The typical GC capillary column consists of a smalldiameter tube with a thin film of a high-molecularweight polymer coated on the inside. The polymer is the stationary phase for the chromatographic process. The mobile phase can be any inert gas, but is typically helium. The instrument also includes a heated injection port to vaporize all volatile constituents of the sample and an oven to keep the constituents in gas form as they pass through the column.

WinRar 4.20

WinRAR is a powerful archive manager. It can backup your data and reduce the size of email attachments, decompress RAR, ZIP and other files downloaded from Internet and create new archives in RAR and ZIP file format.

Version 4.20

1. Changes in RAR compression:

a) RAR general compression algorithm is optimized for better utilization of several processor cores. While some speed gain is possible even in single processor mode, best results are achieved in multi-core environment.
Speed gain depends on data type and average file size. Several cores are utilized more efficiently when compressing large files.

b) we had to increase memory requirements to achieve higher compression speed. General RAR compression algorithm allocates about 120 MB comparing to 40 MB in WinRAR 4.11;

c) RAR text compression algorithm cannot utilize several CPU cores efficiently, so its performance in multiprocessor environment is much lower than for general algorithm. Also its decompression speed is much lower than in general algorithm regardless of CPU number. So we decided to disable the text algorithm by default.

If you need maximum possible compression ratio for plain text data regardless of speed, you can enable the text compression in "Advanced compression parameter" dialog. Press "Compression..." button on "Advanced" page of archiving dialog to access it. You can also change this option permanently in default compression profile; In the command line mode the text compression can be enabled with -mct switch;

d) "Fastest" (-m1) compression mode also supports several processor cores now. In 4.11 it could use only a single processor core.

Thursday, August 9, 2012

Ion Chromatography


Ion chromatography (IC) is the separation and quantitative analysis of anions and cations in an ionic solution using the ion exchange method of liquid chromatography (LC). The chromatographic process separates the different ions within the sample. The amount of an anion/cation is measured by the change in conductivity as the species passes through the detector. The ions in the sample solution are carried through the system by an ionic solution, or eluent (mobile phase). The different ions in the eluent are separated in a column packed with an ion exchange resin (stationary phase). The resin has a thin surface layer of active material with limited ion exchange sites. If anions are to be analyzed, the active sites will have a fixed positive charge to attract the anions. Resins for cation analysis will have a negative charge. Individual ions attach and detach from the resins at a rate depending on the affinity of the specific ion to the active sites. Ions with greater affinity for the stationary phase are retained in the column for a longer time than those with less affinity for the stationary phase. Thus, the ions of particular chemical species in the solution exit or elute from the column within a narrow time band specific to that ion. The detector at the end of the column continuously measures the conductivity of the eluent to determine the quantity of the eluting ions as a function of time. The data from the detector are compiled into a plot of ion abundance versus time, referred to as a chromatogram. The position of a peak in the chromatogram is characteristic of a specific ion. The peak size is a function of the concentration for the ion represented by that peak.

Wednesday, July 18, 2012


Power Plants

Battelle has provided a well-written report that discusses power plant coal utilization in great detail. It gives
a thermal efficiency of 80-83% for steam generation plants and 37-38% thermal efficiency for power generating plants at base load (about 70%). A base load plant designed for about 400 MW and up will run at steam pressures of 2,400 or 3.600psi and 1,000”F with reheat to 1.000”F and regenerative heating of feedwater by steam extracted from the turbine. A thermal efficiency of 40% can be had from such a plant at full load and 38% at high annual load factor. The 3,600psi case is supercritical and is called a once-through boiler, because it has no steam drum. Plants designed folr about 100-350MW run around 1,800 psi and 1,000”F with reheat to 1,000”F. Below 100 MW a typical condition would be about 1,350psi and 950°F with no reheat. Below 60% load factor, efficiency falls off rapidly. The average efficiency for all steam power plants on an annual basis is about 33%.

Monday, July 16, 2012


Affinity laws

Dynamic type pumps obey the affinity laws:

  1. Capacity varies directly with impeller diameter and speed. 
  2. Head varies directly with the square of impeller diameter and speed.
  3. Horsepower varies directly with the cube of impellerdiameter and speed.


The handiest pump horsepower formula for a process  engineer is: 

HP = GPM(AP)/1715(Eff)


HP = Pump horsepower
GPM = Gallons per minute
AP = Delivered pressure (discharge minus suction), psi
Eff = Pump efficiency, fraction

Friday, July 13, 2012


Standard pipe is made in a discrete number of sizes that are designated by nominal diameters in inches, as “inches IPS (iron pipe size).” Table A5 lists some of these sizes with dimensions in inches. Depending on the size, up to 14 different wall thicknesses are made With the same outside diameter. They are identified by schedule numbers, of which the most common is Schedule 40. Approximately,

Schedule number = 1000 PIS,

P = internal pressure, psig
S = allowable working stress in psi.

Wednesday, July 11, 2012

Ultrasonic Cleaning

The material presented in this section features models of ultrasonic cleaners that are unique to this manufacturer. Other sources’ equivalent models’ features should be considered for relevant applications.

Theory of Ultrasonic Cleaning

Everything that makes a sound vibrates, and everything that vibrates makes a sound; however, not all sounds are audible. Ultrasound literally means beyond sound—sound beyond the audible spectrum. Considering 18,000 Hz (cycles per second) as an approximate limit of human hearing, ultrasonics refers to sound above
18,000 Hz.
The ultrasonic power supply (generator) converts 50/60 Hz voltage to high frequency 20 or 40 kHz (20,000/40,000 cycles per second) electrical energy. This electrical energy is transmitted to the piezoelectric transducer within the converter, where it is changed to high-frequency mechanical vibration. The vibrations from the converter are amplified by the probe (horn), creating pressure waves in the liquid. This action forms millions of microscopic bubbles (cavities) that expand during the negative pressure excursion and implode violently during the positive excursion. It is this phenomenon, referred to as cavitation, that produces the powerful shearing action at the probe tip, and causes the molecules in the liquid to become intensely agitated.

Monday, July 9, 2012

How Desalination Works

There are many different techniques for desalination. Among the main ones are the multistage flash (MSF) process and reverse osmosis. Countries that do not have anabundance of fresh water are prime candidates for the use of this technology. Quatar’s installations include the Ras Abu Fontas B power and desalination plant, which cost $1 billion to build. Dubai in the United Arab Emirates (UAE) has a 60- million-gal/day desalination plant at Jebel Ali. The plant’s eight MSF units are part of a cogeneration power facility. The fresh water would have been at least as much incentive in the Middle East as the increased total thermal efficiency. The desalination equipment in both cases was supplied by Weir Westgarth (WW).

WW designed the MSF process. The principle of the system is simple: Water and steam in a closed system can be made to boil at temperatures lower than at standard temperature and pressure by reduction of the system pressure. MSF plants contain a series of closed chambers—as many as 20—each held at a lower pressure than the preceding one.

Saturday, July 7, 2012

(Job Vacancy) Chevron

Chevron is a major partner in Indonesia's economy and an active member of the community. Through our wholly owned subsidiary PT Chevron Pacific Indonesia, we are the largest producer of Indonesia's crude oil. We are searching for new oil and gas reserves from central Sumatra to offshore East Kalimantan. We have begun design work on our deepwater natural gas project off East Kalimantan through Chevron Indonesia Company Our geothermal operations in Indonesia help make Chevron the largest producer of geothermal energy in the world. Chevron sells lubricants in Indonesia through our subsidiary PT Chevron Oil Products Indonesia.

Mooring Master
Kalimantan Timur, Riau

  • Experience at least 4 years as Master Ocean Going in tanker gas and tanker crude.
  • Holding 'Sertifikat Pandu' and STCW '95.
  • Holding ISPS / PFSO Certificate(s).
  • Member of IMO and hold international pilot license to berth and un-berthing Oil and Gas tanker.
  • Familiar with Production Operation.
  • Familiar with Ship, Rig, Tanker and Vessels System and Marine Facilities equipment operation.
  • Physically fit.
  • Willing to relocate to one of Chevron operations locations (East Kalimantan/Riau).
  • Desiring to work in a multicultural and diverse organization.

(Job Vacancy) Chevron

Chevron is a major partner in Indonesia's economy and an active member of the community. Through our wholly owned subsidiary PT Chevron Pacific Indonesia, we are the largest producer of Indonesia's crude oil. We are searching for new oil and gas reserves from central Sumatra to offshore East Kalimantan. We have begun design work on our deepwater natural gas project off East Kalimantan through Chevron Indonesia Company Our geothermal operations in Indonesia help make Chevron the largest producer of geothermal energy in the world. Chevron sells lubricants in Indonesia through our subsidiary PT Chevron Oil Products Indonesia.

Land Officer
Riau - Rumbai

  • Minimum GPA : 2.75
  • Minimum degree : S1 (S2/master degree will be an advantage).
  • Understand of Indonesian laws and regulation on land and forestry.
  • Minimum 3 years in handling land acquisition/land dispute resolution, permitting and other related activities.
  • Has excellent negotiation skills, strong integrity, good personality/ behavior.
  • Willing to relocate to one of Chevron operations locations (East Kalimantan/Riau).
  • Having a good leadership and communication, both in Bahasa or English.
  • Desiring to work in a multicultural and diverse organization.
  • Strong in seeking learning activities.
  • Able to establish effective relationships with people of other culture and backgrounds.


PT. IRAWAN PRIMA UTAMA a well known Contractor, invites qualified and experienced candidates to fulfill the position of:

HSE Engineer
Jawa Barat
  • Male
  • Minimum age 30 years old
  • Candidate must posses at least min D3 or S1 a Bachelor's Degree in Occupational Health and Safety
  • Good Degree from reputable university (min GPA 3,00)
  • Preferably Staffs specializing in HSE Inspector in well known Contractor
  • Responsible and resolute to task
  • At least 1 year(s) of working experience in the related field is required for this position/Fresh Graduate are welcome
  • Willing to be located all over Indonesia
  • Computer literate and good Commad of written & spoke English

If you have the commitment to grow with PT. IRAWAN PRIMA UTAMA, please send your detail CV in English, and must attach health report from doctor with the most recent photograph & indicate your position within 2 weeks to:
Jl. Pahlawan 99 Citeureup – Sentul,
Bogor 16810, Indonesia
Fax (021) 87950735

PT Yamaha Electronics Manufacturing Indonesia

As one of multinational company which has famous brand in the world, we are seeking for talented and high caliber candidate who are looking for more challenges to join as part our growth for the following position :

Production Control ( PC )
Jawa Timur - Pasuruan

  • Male, max 28 years old
  • Single
  • D3/S1 degree majoring Industrial Engineering
  • Min. 1 years experience in PPIC
  • Computer Literate
  • Proficient in English both oral & written
  • Willing to be stationed in Pasuruan

PT. Yamaha Electronics Manufacturing Indonesia
Jl. Rembang Industri II/9-11 PIER Pasuruan Jawa Timur

Email Address :
( email subject : Possition Code_Your name )

(Job Vacancy) PT Prima Energytama

PT. Prima Energytama adalah perusahaan tambang batu bara yang sedang berkembang dan berekspansi besar di wilayah Kalimantan dan Sumatera. Kami mengundang Anda yang berintegritas, dinamis dan bermotivasi tinggi untuk menempati posisi sebagai :

Kalimantan Timur

  • Pria, usia maksimum 30 tahun
  • Lulusan D3 dari segala jurusan 
  • Pengalaman pada posisi yang sama selama 3 tahun atau 1 tahun pada bagian administrasi/mekanik
  • Diutamakan dari perusahaan tambang atau rental alat berat
  • Menguasai Ms. Office & internet
  • Siap ditempatkan di lokasi tambang wilayah Kalimantan

(Job Vacancy) PT Nissan Motor Indonesia

Calling all passionate people in automotive industry!! As an exciting company, NISSAN seek talented people who are not only excited with the roar of cars but also passionate about customer needs, want to improve through continuous learning, and has drive for excellent performance

Engineer Staff
  • Bachelor degree from reputable university, major in Industrial / Electrical / Mechanical Engineering, with GPA min 3.00 out of 4.00.
  • Preferably maximal have1 year experience in manufacturing (fresh graduate are welcome to apply).
  • Single, 22-25 years old.
  • Willing to be placed in Purwakarta.
  • Understand automotive parts and can read technical drawing.
  • Fluent in English is a must, both oral and written.
  • Have high analysis skill, good negotiation & interpersonal skill, communicative, can work under pressure.

Please submit your complete application letter
Before July 31st, 2012to:
(Subject: Engineer Staff)
Only short listed candidates who meet requirement and sent application by email will be notified.

(Job Vacancy) PT Katexindo Citramandiri

PT Katexindo Citramandiri (PMA garment factory) located at KBN Cakung, is a member of TAL Group - world leader in producing innovative clothes that combine style, comfort and function. Our group specializes in the manufacture of quality men’s and women’s garment for the world’s leading brands.

We are looking for highly motivated people to be developed in our dynamic yet challenging environment to fill the post of:

Industrial Engineering
Jakarta Raya - KBN Cakung

Requirements: (please only apply when you really meet the criteria below)
  • Holding S1 Engineering Degree
  • Minimum GPA of 2.75, Male – Female
  • Maximum 24 years old
  • Fresh Graduates
  • Interest in Production Working area
  • Fluent in English is needed (Oral and Written)
  • Will be developed to support plant on concepts, tools, and processes of Production System conversion.
  • Will be developed to do preparation before conversion such as Operator Loading, Layout, Training Plan, improvement of HT – Handling Time
  • Will be developed to perform continuous improvement after conversion with Andon and Kanban concept
  • Willing to work in Cakung Cilincing - Jakarta Utara location
  • Lunch and Shuttle Bus transport provided for particular routes
  • Full Time Permanent Position Offered

(Job Vacancy) PT Nakajima All Indonesia

We are an electronic private company located in East Karawang, need URGENTLY,2 ( two ) Engineering Staff  with qualifications :

Engineering Staff
Jawa Barat

  • Male
  • D3 /S1  Fresh graduated welcome, have experience will be adventage
  • D3 /S1 degree majoring in Electronic and majoring in computer
  • Fluent English
  • For Computer, has knowledge of Linux and PHP

(Job Vacancy) PT Graha Kerindo Utama

We are a fast growing company, have achieved TOP BRAND and also one of business unit of KOMPAS GRAMEDIA that produced TISSUE TESSA, MULTI, and DYNASTY. In order to do a BIG PROJECT, this strategic position is solely intended for those of you who meet the qualifications for this position:

Jawa Barat - Cibitung (Bekasi) or Dawuan (Cikampek)

  • Male with age <29.
  • Bachelor in Industrial from reputable university with minimum GPA 3.00.
  • Minimum 2 years experience in Manufacturing Industry.
  • Understanding the basis of plant management, management of industrial processes; have good planning, monitoring, analysis, and evaluation; and able to calculate estimates.
  • Computer literate (Microsoft Office).
  • Willing to be placed in Cibitung (Bekasi) or Dawuan (Cikampek).

(Job Vacancy) PT Herman Industries


Currently we are looking for highly qualified, self starter, hard working and strong leadership professional qualification to fill up the following position as :

Jakarta Raya
  • Candidate must possess at least a Diploma, Engineering (Electrical/Electronic) or equivalent.
  • At least 3 year(s) of working experience in the related field is required for this position.
  • Preferably Supervisor / Coordinators specializing in Engineering - Electrical or equivalent.
  • Full-Time position(s) available.

Lamaran dan CV lengkap dikirim ke: atau

Jl. KH. Zainul Arifin No. 3B, Jakarta Pusat

Friday, July 6, 2012

Fans, Centrifugal

Besides being used in process plants, centrifugal fans are common in building heating and air-conditioning systems. Vendors for these systems should be consulted for required options

Types of Fans

Three types of centrifugal fans are available: (1) forward curved blade fans, (2) radial blade fans, and (3) backward curved blade fans. The characteristics of the forward curved blade fan make it the most appropriate type of cooling tower service. By virtue of the direction and velocity of the air leaving the fan wheel, the fan can be equipped with a comparatively small size housing, which is desirable from a structural standpoint. Also, because the required velocity is generated at a comparatively low speed, forward curved blade fans tend to operate quieter than other centrifugal types. Note the relatively small rpm and head values. The envelopes on the head versus volume curves each indicate a separate fan model is available. Centrifugal fans are usually of sheet metal construction, with the most popular protective coating being hot-dip galvanization. Damper mechanisms are also available to facilitate capacity control of the cooling tower.


All propeller-type fans operate in accordance with common laws. For a given fan
and cooling tower system, the following is true:
1. The capacity (cfm) varies directly as the speed (rpm) ratio, and directly as the
pitch angle of the blades relative to the plane of rotation.
2. The static pressure (hs) varies as the square of the capacity ratio.
3. The fan horsepower varies as the cube of the capacity ratio.
4. At constant cfm, the fan horsepower and static pressure vary directly with the
air density.
If, for example, the capacity (cfm) of a given fan were decreased by 50 percent
(either by a reduction to half of design rpm, or by a reduction in blade pitch angle
at constant speed), the capacity ratio would be 0.5. Concurrently, the static pressure
would become 25 percent of before, and the fan horsepower would become 12.5
percent of before. These characteristics afford unique opportunities to combine cold
water temperature control with significant energy savings.

Wednesday, July 4, 2012

Cooling Towers: Design and Operation Considerations

Cooling towers are a very important part of many chemical plants.  They represent a relatively inexpensive and dependable means of removing low grade heat from cooling water.
Closed Loop Cooling Tower System

The make-up water source is used to replenish water lost to evaporation.  Hot water from heat exchangers is sent to the cooling tower.   The water exits the cooling tower and is sent back to the exchangers or to other units for further cooling.



Natural gas and crude distillates such as naphtha from petroleum refigare used as feedstocks to manufacture a wide range of petrochemicals that are in turn used in the manufacture of consumer goods. Basic petrochemicals are manufactured by cracking, reforming, and other processes, and include olefins (such as ethylene, propylene, butylenes, and butadiene) and aromatics (such as benzene, toluene, and xylenes). The capacity of naphtha crackers is generally of the order of 250,000 to 750,000 metric tons per year (tpy) of ethylene production. Some petrochemical plants also have alcohol and oxo-compound manufacturing units on site. The base petrochemicals or products derived from them, along with other raw materials, are converted to a wide range of products.

Thursday, June 7, 2012

Detective Conan Manga

Categories: adventure, anime, comedy, live action, mystery, shounen
Author: Aoyama Gosho
Artist: Aoyama Gosho
Original Publisher: Shogakukan
US Publisher: Viz Media
Start Date: 2000
Chapters: 721 - ongoing - weekly

When ace high school detective Kudou Shinichi is fed a mysterious substance by a pair of nefarious men in black--poof! He is physically tranformed into a first grader. Until he can find a cure for his miniature malady, he takes on the pseudonym Conan Edogawa and continues to solve all the cases that come his way.


Volume 1-5 = Maknyos

Volume 6-10 = Mediafire

Volume 11-20 = Mediafire

Volume 21-30 = Mediafire

Volume 31-40 = Mediafire

Volume 41-45 = Mediafire

Volume 46-50 = Mediafire

Volume 51-55 = Mediafire

Volume 56-60 = Mediafire

Monday, June 4, 2012

Sweet Home 3D

Sweet Home 3D is a free interior design application that helps you place your furniture on a house 2D plan, with a 3D preview

You may download Sweet Home 3D to install it on your computer and/or use it online within your browser:

Download Sweet Home 3D


Use Sweet Home 3D Online

Sweet Home 3D is available in English, French, and 19 other languages. It may run under Windows, Mac OS X 10.4 to 10.7, Linux and Solaris.