Swro Design and Energy Recovery Part 3: Major Component Selection

The sand screens and micron filters were selected because of the durable and corrosion resistant fiberglass and PVC construction. The specific model of Eden micron filters was chosen to maintain the filter element flux at approximately 3.3 gpm/per 10″ equivalent.

Due to the relative remoteness of the installation site, multistage-centrifugal, high-pressure pumps have been selected for their reliability, availability of parts, economics of operation and easy maintenance. Centrifugal pumps in general are smoother, quieter, and require less ancillary equipment (i.e. pulsation dampeners) than positive displacement pumps. Hydropro has found that positive displacement pumps are much more prone to failure and lengthily downtimes than high-quality centrifugal pumps.

The Grundfos Booster Modules were chosen for several reasons. The inline style helped conserve space and provided ease of installation, allowing everything to be mounted on the same skid (with the exception of cleaning/flush tanks, raw water booster pumps, and chemical feeds). These submersible, multi-stage centrifugal pumps were also chosen because they are very efficient and quiet, and are constructed of corrosion resistant, 904L super austenitic stainless steel.

The high pressure feed and concentrate headers were made of 2205 duplex stainless steel for superior corrosion resistance, and the structural skid was constructed of FRP for low weight and zero maintenance. ERI´s Pressure Exchanger was chosen because of its high energy efficiency, dependability, and corrosion resistant materials.

Performance
Values for the projected power consumption rates that were presented in the proposal were based on a 27ºC feed stream of 45,000 mg/l TDS and a permeate flow rate of 100,000 gpd. The membrane manufactures projection software was used to determine the system parameters at a recovery of 35%, and these parameters were subsequently used to determine the projected power consumption. The result was an anticipated feed pressure of 900 psi and a specific power consumption rate of 3.02 kWh/m³.

Once the system was installed and operating, the specific power consumption was calculated based on actual system parameters and the result was a much lower value of 2.65 kWh/m³. There were several reasons the actual value was lower, the main reason however, was the conservative design. Because of some uncertainty in the feed water quality, the SWRO system was designed with a relatively low flux (approximately 8 gpm/ft2), and a somewhat large hydraulic envelope. As it turned out, the feed water TDS was closer to 36,000 ppm and fairly stable. The lower feed TDS enabled the system to operate at a lower membrane feed pressure of 790 psi and a higher permeate flow rate of 120,000 gpd, consequently using less energy than originally projected and making higher quality permeate.

Conclusion
With most of the system assembled, the installation was fairly straightforward and went smoothly. The two units were installed, started up, tested and operator training was completed in less than three weeks. There was, however, a problem with the feed water quality and the pretreatment system, which was discovered after only 24 hours of operation. It immediately became apparent that the raw water was loaded with particulate that was quickly fouling the sand screens and the micron filters. Fortunately, the feed system could be modified to flow into an existing 250,000 gallon seawater tank from the wells, and the SWRO feed was then drawn out of this tank. This settling tank solution worked quite well and provided a feed water with a pre-filter SDI of 1.25.

There was also one other performance issue that needed to be resolved. Initially, the permeate quality was less than what was projected, and it was not clear why. The system was extensively checked ant tested for leaks, and the possibility that seawater was somehow mixing with the permeate was eventually eliminated. It was finally determined that the membranes did not meet the design rejection required to produce the projected permeate TDS. Once the membranes were replaced, the system was making plenty of high quality permeate that was well below the maximum acceptable permeate TDS.

KAJUR and the residents of Ebye have since been enjoying low-cost, high-quality water for over a year now without any noteworthy system failures. They are so pleased, in fact, that KAJUR has recently awarded Hydropro another SWRO job utilizing work exchanger energy recovery.

by roplant

Ocean Thermal Energy

Thermal energy is renewable and is generated without an impact on the environment. In layman’s terms, thermal energy can be transferred to other objects, heating them, causing the molecules to move faster. Ocean thermal energy is a popular form of solar energy. The United States took a strong interest in ocean thermal energy plants in 1974 and has since expanded their use.

Ocean thermal energy generates electricity by using the temperature difference between deep and shallow waters. Typically, this energy is used to run a heat engine. The greatest amount of energy is generated by the largest differences between temperatures. For this reason, ocean thermal energy is most easily generated near the equator and in the tropics.

Oceans cover over 70% of the Earth, which the sun has time to heat on a daily basis. If made cost-effective, ocean thermal energy could solve the world’s energy needs. Currently, the efficiency of ocean thermal energy is a mere one to three percent.

Ocean thermal energy technology uses a heat engine, which is technology that is used through the majority of energy generation today. The heat engine is placed between a high temperature reservoir and a low temperature reservoir. The heat flows from one reservoir to the other, and is then converted into energy. This technology is extremely popular and is used in common engines. The reverse concept is used in refrigerators.

Ocean thermal energy has benefits other than power. Air conditioning can be produced nearby thermal energy plants. The cold seawater used for the plants can be used in water coils. This thermal energy can provide enough air conditioning for a large building, saving 0,000-0,000 annually in energy bills.

This technology also produces chilled water for agriculture. Chilled-soil agriculture requires cold sea water to flow through underground pipes, thus chilling the surrounding soil. This temperature difference between the soil and the plant leaves allows the plants to feel as if they are grown in the subtropics.

Desalinated water can also be produced with the use of ocean thermal energy. This can be produced in open- or hybrid- cycle plants using surface condensers. This is done by condensing steam by indirect contact with cold sea water. This creates relatively low levels of impurities in seawater and allows for drinking.

This is the extended version. Part 1 of a 4 part series boiling 5 gallons of water. This is a very hard task and while I could have easily boiled 1 gallon, I wanted to test the limit of the lenses. Watch all the videos, there is a lot of info. www.greenpowerscience.com

Video Rating: 4 / 5

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by iliveisl

Ashley Montgomery, energy, ERII, NASDAQ, Water Conversion, Wolrd Market Media Stocks: ERII

Humanity faces a global water supply crisis. Less than 1% of all fresh water is readily accessible for human use and more than 1.8 billion people lack adequate access to drinking water. As water extraction levels from rivers, lakes, and aquifers approach historically maximum levels, water scarcity remains a serious concern across the globe. Entire regions in North Africa, as well as Australia and the Indian subcontinent, are unable to meet the water demands of urban areas and local farmers. Dwindling water supply is also an issue here in the United States.

To help mitigate this mounting scarcity, the process of converting seawater into freshwater emerged as a potential source of new and abundant supply. However, older methods of desalinating seawater consumed significant amounts of energy, and historically desalination has been an unaffordable, impractical solution for most regions. Energy Recovery, Inc. (NASDAQ: ERII) has designed and developed an innovative technology that dramatically reduces the energy required for seawater desalination.

ERI’s Pressure Exchanger™ (PX™) device recycles much of the energy used in seawater desalination by continually reclaiming the otherwise lost pressure energy from the reject or brine water with to up to 98% efficiency. This improves the energy efficiency of seawater reverse osmosis (SWRO) by up to 60%, making desalination an affordable, sustainable option to address the world’s water crisis. This is significant because in a typical desalination plant the large electric motors driving the pumps consume dozens of megawatts of energy. Every percent of improvement in efficiency, therefore, means millions of dollars in energy savings over the life of the plant; thus enabling large desalination plants to affordably supply much of the demand for fresh-water to cities around the world.

ERI’s PX devices currently save more than 750 megawatts of energy and are reducing CO2 emissions by more than 4.6 million tons per year. More than 7,000 PX devices are in the market, supporting the production of drinking water for an estimated 25 million people globally. The sapphire-like material makes the PX device a very reliable, low-maintenance solution, which has captured 70% of global market share in newly constructed large desalination plants worldwide.

Today, Energy Recovery Inc. topped the list of Biggest Percentage Price Gainers among common stocks on the Nasdaq Stock Market. The company is currently trading at .42, up .62 or 16.32%.

On Wednesday, June 16th, it released press that President and CEO G.G. Pique would deliver a presentation at the Clean Technology Conference and Expo (June 21-24, 2010 at the Anaheim Convention Center in Anaheim, California). “Global water shortages have reached crisis levels: As many as one in eight people lack safe water supplies, and the United Nations estimates that a child dies from water-related diseases every 15 seconds. Developing and industrialized nations alike face major decisions about how to address a looming — and inevitable — global water deficiency,” said Pique. “For years, Energy Recovery has been at the forefront of helping to advance desalination as a long-term, economically viable solution. I look forward to speaking at the Clean Technology Conference & Expo to demonstrate how our Pressure Exchanger™ (PX™) isobaric energy recovery device makes desalination a far less energy-intensive process and plays a key role in sustainably addressing global (and domestic) water scarcity.”

To view this article at World Market Media click on the link below: http://www.worldmarketmedia.com/779/section.aspx/1964/post/energy-recovery-inc-nasdaq-erii-230m-marketcap-16

Disclosure: no positions

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Automatic Stretch Pet Blowing Machine

Automatic Stretch Pet Blowing Machine

All the qualities of PET :

The PET bottle is a great success in many countries. And no wonder, producted by
the biaxially oriented blow moulding process, PET or Polyethylene Terephtalate –
bottles combine outstanding performance and aesthetic qualities. These give you
the superb crystal clarity needed to show any product to advantage. They have
excellent carbonation retention properties and good barrier to oxygen. Extremely
resistant to breakage, light to handle and transport and safe to health and
environment.

With Canadian clear system flexibility:
To the advantage of PET itself, the extraordinary characteristics of the SSB 10 to
SSB60 are added: simplicity, compactness, reliability and flexibility.
Quickly installed, the machine is ready for producing bottles of various shapes and
contents as the changes of the moulds are rapid. Renowned for these advantages,
it is the small “two step” machine which is the most sold in the world and gives
satisfaction to hundreds of producers for very different applications:mineral
water, carbonated drinks, edible oil, detergents…

This is the ideal system for the economical production, in small series, of quality
bottles.

The Quartz Oven :

Eight vertically, horizontally and angularly adjustable double lamps can be
returned to all a more uniform heating of any type of preforms before
blowing. Preheating is achieved by recirculating hot air exhausted by lamps
and the system automatically adjusts to changes in the ambient
temperature.

An oven with ten lamps (optional) permits the heating of thicker preforms.

The Control Cabinet :

The control cabinet is equipped with a programmable microprocessor with Error
Status indicator. Setting and adjusting of the controls can be performed manually.
For special climates the cabinet can be air conditioned.

Easy Access:
The pneumatic, hydraulic and electrical equipments, as well as the cooling system,
are easily accessible.
Minimum replacement time is required when one type of bottle mould is changed
for another one. No special tools are needed.

The Bi-Axial Orientation:
PET is certainly the ideal material, but to retain that title, it also needs the full
benefits of bi-axial orientation.
Bi-axial orientation requires two stage production. The preform is first produced
and then, within a precise temperature range, it is simultaneously stretched both
axially, (thanks to stretching rods), and radially by blowing. It is this process
which gives the container its strength.

These two phases can be carried out on one double acting machine (one stage) or
separately on two different machines (two stages).
But the new generation of application is covering a still more extensive range :
detergents and cleaning products., wine and other alcoholic – drinks, fruit juices,
certain conserves, sauces, ketchup and mustard, cosmetic and pharmaceutical
products, industrial paints and oils, chemical products etc.,

A range of new markets with a promising potential.
Specialized in the manufacture of bi-oriented stretch blow moulding machines for
PET containers (starting from preforms), Canadian Clear is offering today a
completely upgraded range of small and medium capacity blow moulding units.
They combine the proven simplicity and reliability of the linear machine concept
with the most recent developments in the field of PET process technology. A state
of the art, user friendly operator machine interface (graphic display) allows easy
programming of all relevant production parameters, ensuring at the same time
extremely fast product change-over. Special equipment packages are available for
the production of refillable or hot fit PET bottles, PEN/PET bottles and bi-oriented
PP-bottles.

Advantages of a flexible system :
A system of small modular units has many advantages over one large machine.
You can begin small with the minimum investment.
As business grows, additional units can be acquired.
Production volume can easily and economically be adjusted to market fluctuations.
Bottles of different sizes and weights can be produced simultaneously on different units.
Change over from one production to another can be rapidly effected.
The equipment design is simple and, as a result, the tooling costs are low.
The Canadian Clear system is well known for its solidity and reliability according to world standards.
A simple system to operate means short training for operators.
As the machine requires very little maintenance, cost related to non operating machines are negligible.

www.canadianclear.com

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by roplant

Mouli Cohen on Saudi Arabia as a New Energy Reserve

In his regularly maintained blog, MouliCohen.Net, Mouli Cohen talked about how the discovery of oil in Saudi Arabia over 70 years ago has completely changed its reputation and image to the rest of the modern world. Cohen, who has ventured into his many technological and biotechnological interests, said that Saudi Arabia has turned into one of the biggest Arab nation in the Middle East. He also put emphasis on how this bold move completely changes and revitalized the Kingdom’s economy and industry.

However, in the present, the Kingdom has been aiming to achieve a better reputation by effectively harnessing the sun’s power as an energy source. The Royal Embassy of Saudi Arabia has started to adapt a three-part program that aims to introduce the use of solar energy for the rest of the kingdom. The country has also begun the process f desalinating the power from the sun to boost its efficiency and effectiveness.

Desalinization, which has become a crucial process to maintain the world supply of water, needs a big amount of energy to carry out. Instead of relying on its big reserve of energy from oil, Saudi Arabia has begun to explore the possibilities of using a greener source of energy. Through this, they can allot the extracted oil to other needs and concerns.

Mouli Cohen highlighted the fact that the largest exporter or oil has started to utilize a more ecofriendly energy source. On this note, he also urged other big countries and business entities to start adapting similar undertakings.

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