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Flow Meters for the Environment

Water desalination is the process of removing soluble salts from water to render it suitable for drinking, irrigation, or industrial uses. The principal methods used for desalination include distillation, electrodialysis, freezing, ion exchange, and reverse osmosis. Reverse osmosis desalination plants require substantially less energy than do thermal desalination processes, such as multi-stage flash, making them substantially more cost-effective.

Water desalination is an alternative for water supply enhancement. Dam construction will reduce the annual flow of rivers thus reducing our water supply. Flow meters are used in the process to control the flow of water in reverse osmosis during the desalination industry: Desalination of water is possible through reverse osmosis and the system plays a key role in advancing water reuse and purification. Small reverse osmosis units using PV systems for water purification can be used in rural places and businesses to transform seawater and brackish water into fresh water for drinking, irrigation, and industrial applications.

This particular ecomagination breakthrough couldn't come at a better time. Water scarcity affects 1 in 5 people and that number will climb to 3 in 5 in 20 years. Currently, more than one billion people do not have access to safe water to meet their daily needs. Forty percent of the world's population currently lives in areas with moderate-to-high water stress. By 2025, it is estimated that about two-thirds of the world's population, about 5.5 billion people, will live in areas facing such water stress.

The Earth's surface may well be 70 percent water, yet less than one percent of it is usable and not always located where it's needed most. Each year, 22 percent of the world's water supply is used for industrial purposes. Much of that water is not reused. Reverse osmosis desalination plants require 25 percent less land area than competing desalination platforms, reducing their environmental footprints. They are capable of producing water reliably and affordably from almost any salt or brackish water source.

If all existing multi-stage flash desalination plants switched to energy-efficient reverse osmosis, the overall reduction in greenhouse gas emissions annually would equal more than the emissions given off by 73 million cars. It would be like taking half of all automobiles off the U.S. roads.

Brackish Water and Seawater Desalination supply Reliable fresh water supplies from challenging water sources

Brackish Water and Seawater can be economically treated with reverse osmosis and electrodialysis reversal systems. Effective mineral and salt removal converts previously unusable water to high-purity resources for drinking, irrigation, or industrial processes.

The world's water consumption rate is doubling every 20 years. It is projected that by the year 2025 water demand will exceed water supply by 56%. This is caused by persistent regional droughts, shifts in population in coastal cities, and water needs to support industrial growth. Water demand for food, industry, and people continues to rise as the supply of fresh water decreases.

Flow meters reduce environmental taxation by reducing energy usage.

Flow meters are used as a method for improving thermal efficiency of fossil fueled power plants. They regulate the boiler cycle by controlling the amount of fossil fuel used. The flow meter adjusts the flow rate to maximize combustion, which is the means by which a working fluid is heated. The combustion of the fuel produces effluents in an exhaust and a turbine cycle in which the working fluid does its work.

The current of an electric source of supply feeds two rheostats of a flue gas flow and a stream flow meter to run a steam boiler efficiently. The flow meter provides accurate fuel distribution and enables lower excess air to increase boiler efficiency. A flow meter is connected to a pipe in each flue-gas to the leading to the boiler to heat the conduit. The flow meter properly adjusts the air supply to maintain a consistent flow, thus optimizing operation of the boiler. Flow meters allow for boiler optimization for multiple boiler heating plants. They are the best method for optimizing the performance of a multi-unit power plant.

Energy use and our environment coupled human activities are inexorably impacting our global climate. It has also been estimated that more than 85% of our influence on climate is a direct result of energy use more energy use equals more greenhouse gas emissions.

It is well known that adding hydrogen, using a flow meter to monitor amounts, to natural gas extends the lean limit of combustion and that in this way extremely low emission levels can be obtained, even the equivalent zero emission vehicle requirements can be reached. The emissions reduction is especially important at light engine loads.

Natural gas, pure hydrogen, and different blends of these two fuels have been tested. The fuel supply system used provides a natural gas/hydrogen mixture in variable proportions, regulated by flow meters independent of the engine operating condition. The influence of the fuel composition on the engine operating characteristics and exhaust emissions has been examined. It has been discovered that at least a 10 percent hydrogen addition is necessary for significant improvement in efficiency. The mixture composition should be varied with respect to engine load.

Flow meters are used in the current apparatus and method for determining evaporative emissions relates to motor vehicle emissions testing and for automatically testing motor vehicle evaporative emissions. In addition to commonly known tailpipe exhaust emissions produced during engine operation, there are also evaporative emissions, which are generated while the vehicle is simply sitting parked.

Modern regulations require measuring evaporative emissions produced by a vehicle over the course of several days and in response to changing temperature conditions. This presents a problem in that changes in air temperature cause corresponding changes in the volume and hence changes in the pressure of the ambient air structure.

In addition, pressure differences between the interior and the ambient air and the outside environment encourage migration of air either into or out of the testing structure through leaks. This affects the accuracy of the test results. Therefore, it is necessary to control the pressure changes to maintain a pressure difference between the interior of the structure and the surrounding outside atmosphere. This is where a flow meter is absolutely necessary to maintain steady pressure, nearest zero.

Measurement by a direct mass flow meter is accurate and cost effective. Volumetric flow metering is proportional to mass flow rate only if the density of the fluid or gas is constant. If the fluid or gas contains any irregularities, the volume flow rate is not an accurate measure.

In fluid dynamics, the volumetric flow rate is the volume of fluid or gas passing through a given volume in a given time frame. Given an area (A) and a fluid flowing through it with uniform velocity (v) the flux is:

Q = A \cdot v \cdot \cos \theta.

If the velocity of the fluid or gas through the area is non-planar, the rate of fluid flow can be calculated by means of a surface integral, but is not completely accurate. In a mass flow meter the fluid or gas is contained in a smooth tube, with no moving parts that would need to be cleaned and maintained, and that would impede the flow.

Mass flow meters provide immunity to process changes and supply very repeatable measurements. In Gases, density is highly variable. This makes volumetric gas flow very sensitive to changes in pressure and temperature. Mass flow meters are used in emissions testing because they are more accurate.

There are two types of Emissions tests in use. All official test procedures also call for a physical inspection to determine that all of a vehicle’s emission control equipment is still in place. This is enforced to varying degrees, but should be considered when thinking about removing equipment, such as the fuel injection, camshafts, and compression ratios to save repair costs or looking for more performance.

Both tests are looking for the same gasses:

• Carbon Monoxide
• Hydrocarbons
• Carbon Dioxide
• Oxygen

The most common test is one that measures the exhaust gas content with the engine idling. The test equipment is based on what is known as a four gas analyzer. The machine is equipped with a flow meter to record the amount of Carbon Dioxide, Carbon Monoxide, Oxygen content, and unburned Hydrocarbons. This test is usually combined with a computer to set test parameters such as vehicle year, test limits etc. This machine also uses another device to monitor engine speed during the test. This insures that the engine is at a proper speed to run the test. This type of test will eventually be required everywhere in an effort to reduce emissions.

The other test is more complex and requires much more complicated flow meters, including a Chassis Dynamometer. This test actually simulates driving the vehicle in real world conditions for four minutes. As the vehicle undergoes changing speeds and loads, the test can accurately determine the performance of a vehicles emission control systems. This test measures the actual volume of certain pollutants being produced. It can also measure the oxides of nitrogen, a component of smog, as the engine will be operated under load. This test system will be used for state centralized emissions testing programs and will be required in many areas as it enables more accurate readings.

The greenhouse effect, first discovered by Joseph Fourier in 1824, and investigated quantitatively by Svante Arrhenius in 1896, is the process by which the emission of infrared radiation in an atmosphere warms a planet's surface. In the case of the Earth, without these greenhouse gases its surface would be up to 30°C cooler. The name comes from an incorrect analogy with the way in which greenhouses are heated by the sun in order to facilitate plant growth. In addition to the Earth, Mars and Venus have greenhouse effects.

Hydrocarbons, carbon monoxide and oxides of nitrogen are created during the combustion process in a automobile and are emitted into the atmosphere from the tail pipe. There are also hydrocarbons emitted as a result of vaporization of gasoline and from the crankcase of the automobile. The clean air act of 1977 set limits as to the amount of these pollutants that can be emitted from an automobile. The manufacturers answer was the addition of certain pollution control flow meters and the creation of a self adjusting engine. In 1981 the first of these self adjusting engines was produced to study the effects of emissions on the atmosphere and flow meters became widely used in an effort to keep high emission vehicles off the road.

By using accuracy instruments, such as flow meters, waste can be reduced greatly. Flow meters are used as a method for increasing the cross-flow microfiltration fluxes of waste waters systems of a nuclear power plant. They regulate the flow of dry compressed air and are used in treating paint wastes. They are used as an apparatus for pollution control of industrial waste systems and in allocation of the cost of natural gas, emission of nitrous oxide and other trace gases during composting of grass and green waste, processing acidification for biomethanation of vegetable market waste, and as a method of handling radioactive alkali metal waste from recycling of cadmium from battery waste by regulating the chlorination. Flow meters also regulate flue gases related to waste incineration conditions. The use of flow meters raises awareness by forcing everyone from corporation to physical plant to individual to monitor their waste. They are a small device serving a huge cause.

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