Friday 6 June 2014

Direct Drive Wind Turbines.........The Power Generators!!!

Can we use wind to generate power???...Oh yes we can!!....as we all are familiar of wind turbine which generate power(electricity) through their motors and fan motion due to heavy wind.A wind turbine is a device that converts kinetic energy from the wind into electrical power.

TYPES
  • Horizontal Axis Wind Turbine - A horizontal Axis Wind Turbine is the most common wind turbine design. In addition to being parallel to the ground, the axis of blade rotation is
    parallel to the wind flow.
  • Up-Wind Turbines - Some wind turbines are designed to operate in an upwind mode (with the blades upwind of the tower).Large wind turbines use a motor-driven mechanism
    that turns the machine in response to a wind direction. Smaller wind turbines use a tail vane to keep the blades facing into the wind.
  • Down-Wind Turbines - Other wind turbines operate in a downwind mode so that the wind passes the tower before striking the blades.Without a tail vane, the machine rotor naturally tracks the wind in a downwind mode. 
  • Shrouded Wind Turbines - The Savonius turbine is S-shaped if viewed from above. This drag-type VAWT turns relatively slowly, butyields a high torque. It is useful for grinding grains pumping water, and many other tasks, but its slow rotational speeds make it unsuitable for generating electricity on a large-scale.                 
    Source - Google Image
Not all the energy of blowing wind can be harvested, since conservation of mass requires that as much mass of air exits the turbine as enters it. Betz' law gives the maximal achievable extraction of wind power by a wind turbine as 59% of the total kinetic energy of the air flowing through the turbine.

 Further inefficiencies, such as rotor blade friction and drag, gearbox losses, generator and converter losses, reduce the power delivered by a wind turbine. Commercial utility-connected turbines deliver about 75% of the Betz limit of power extractable from the wind, at rated operating speed.
 Efficiency can decrease slightly over time due to wear. Analysis of 3128 wind turbines older than 10 years in Denmark showed that half of the turbines had no decrease, while the other half saw a production decrease of 1.2% per year.

 The direct drive (gearless) wind turbine is the low-speed generator that eliminates the need for a gearbox from the turbine’s drive train. These turbines have advantages such as - these are lighter as compared to conventional turbine, these have significantly lower maintenance costs, and it is not needed to replace gearbox as these are gearless turbines. The most preferred direct drive wind turbine generator is the permanent magnet type generator, as it is lighter in weight and possesses high reliability for offshore applications.

Market Forecast

The global direct drive wind turbine market revenue is estimated to be $11.7 billion in 2011 which is estimated to reach $23 billion by 2017, at a CAGR of 15.2% from 2012 to 2017. In the global direct drive wind turbine, the permanent magnet synchronous generator captures the largest market at present share followed by electrically excited synchronous generator. The category 1 - 3 MW captures the largest market share followed by less than 1 MW and then above 3 MW.




Friday 30 May 2014

CRYOGENIC EQUIPMENTS - THE GASS COOLERS!!!

Cryogenics is the study of materials,about their behavior and production,particularly at low temperature(below −150 °C, −238 °F or 123 K). These temperature are known as cryogenic temperature. Liquified gases are handled using cryogenic equipments to maintain them in liquid state,as normal equipments wont sustain them.
Source - Google images










Types                                       
  • Tanks
  • Valves
  • Vaporizers
  • Pipes
  • Cold traps
  • Containers  
  • Pressure vessels and purifiers 
 In many cases, this equipment holds or assists in the transport of supercooled liquids, such as liquid helium, nitrogen, oxygen and argon. Transfer lines, for example, provide a safe means to transfer liquid cryogens from one location to another without endangering workers or machinery.

Proper insulation is often key to the effectiveness of cryogenic components, as it ensures that temperature levels are maintained within the equipment. Similarly, insulation protects equipment users from dangerous temperatures and materials during handling. Of the liquids regularly used in cryogenic operations, nitrogen and helium are the most common; liquid helium allows for extremely low temperatures. Also important to most cryogenic equipment, especially valves, gages and piping systems, is the pressure rating of the unit; the majority of cryogenic systems have specific pressure requirements in order to retain fixed temperatures.

Some cryogenic equipments are

JEOL JFD-9000 freeze-fracture device
    cryopump/shroud configuration (10-8 torr)
    high resolution metal/carbon coating
    single and double replica methods

REICHERT Cryofract freeze-fracture device
     ion pump/shroud configuration (10-7 torr)
    operates at either liquid N2 or He temperatures
    double replica methods

EMscope SP-2000A cryopreparation station (SEM)
    super-cooled liquid nitrogen freezing chamber
    cryo-sputter chamber, flash carbon evaporation
    sublimation stage, vacuum transfer station
    cryoSEM stage and airlock interface to the ETEC Autoscan

GATAN Cryotransfer microscope stage (to -150° C)
     interface to JEOL JSM-880 and 2000-FX

RMC MF-7200 Propane jet ultrarapid freezing device
    state-of-the-art freezing in 1 millisecond
    suitable for biologicals and emulsions

Cryogenic Equipment Market

The global market revenue is estimated to be $11 billion in 2011. The market will grow by 8.2% in 2012 to $11.9 billion by 2017. Energy and power sector holds the largest share in cryogenic equipment revenue. Chemical industry is the second largest share holder followed by metallurgical industry.Asia-Pacific region is the largest market for cryogenic equipments with 37% market share of global cryogenic equipment revenue. After Asia-Pacific, Europe, and North America regions are the second and third largest market respectively.
 
For more info,visit-

Friday 23 May 2014

Concrete Admixtures - additives to sturdy concrete


Concrete admixtures are additives added to concrete to strengthen,chemically resist,color resist,reduction in water and cement requirement and to enhance working properties of concrete.

Types of admixtures
  •  Shrinkage reducers    
  •  Corrosion inhibitors
  •  Hydration-control admixtures
  • Retarding admixtures
  •  Accelerating admixtures
  • Plasticizers
  • Water-reducing admixtures
  • Air-entraining admixtures
  • Alkali-silica reactivity inhibitors
  • Coloring admixtures  



Source-http://www.admixtures.com/images/Ctrl_BoomImage/boom_uid5192009313442.jpg

WATER-REDUCING ADMIXTURES  

Water-reducing admixtures are used to reduce the quan-tity of mixing water required to produce concrete of a certain slump, reduce water-cement ratio, reduce cement content, or increase slump. Typical   water reducers reduce the water content by approximately 5% to 10%. Adding a water-reducing admixture to concrete without reducing the water content  can produce a mixture with a higherslump.The rate of slump loss, however, is not reduced and in most cases is increased . Rapid slump loss results in reduced workability and less time to place concrete. An increase in strength is generally obtained with water-reducing admixtures as the water-cement ratio is cracks in concrete. Using a water reducer to reduce the cement and water content of a concrete mixture—while maintaining a constant water-cement ratio—can result in equal or reduced compressive strength, and can increase slump loss by a factor of two or more (Whiting and Dziedzic 1992).

 Reasons for using admixtures 
  • To maintain the quality of concrete during the stages of mixing, transporting, placing, and curing in ad-verse weather conditions.
  • To achieve certain properties in concrete more effectively than by other means.
  • To reduce the cost of concrete construction
  • To overcome certain emergencies during concreting operations. 

Concrete Admixtures Market Forecast

The global construction industry was one of the highest booming markets in the 2000 decade. Most of the cement and admixtures companies have grown immensely during this era. However, the industry has been through a huge difficulty in last few years due to global financial crisis observed in the year 2009. Especially, the construction markets from Europe and North America were in deep hindrance. The industry showed a downfall in the Asia Pacific and Middle East region too, however, the effects were not as adverse as observed in other regions. The collapsed construction industry affected cement and admixtures consumption along with production.

for more info , visit -

http://www.marketsandmarkets.com/Market-Reports/concrete-admixtures-additives-market-768.html

 

 
 



    Friday 16 May 2014

    The perfect booster for soil

    Fertilizers, as we all know, are added to soil to boon the growth of plants as they supply vital nutrients for plants growth.Fertilizers may be organic or inorganic yielded naturally or synthetic. Depends on the nature of the soil, such as whether it is acidic or alkaline; sandy, clay or rocky; and weak or rich, the choice is made for the fertilizers to be used for speed growth.

    Types

    Organic


            


    These are natural and includes things such as bat guano, compost, peat moss, wood ash and manure, generaly soil amendments. They don't burn or harm plants, and they can have long-term positive effects on the soil without damaging groundwater.But they generally have lower nutrient concentrations than inorganic  fertilizers 
       
    Source - http://patwelsh.com/wpmu/files/Options-for-Organic-Fertilizers_large-300x270.jpg


    Inorganic




    Typically comes as a powder, pellets, granules or a liquid , which are man-made. Plants absorb nitrogen (N), phosphorus (P) and potassium (K) as chemical additives which are examples of inorganic fertilizers.These three essential elemental nutrients should naturally occur in healthy soil, but some plants require more of them. Other chemicals that might be included in inorganic fertilizers include calcium, sulfur, iron, zinc and magnesium.

    Source -http://www.buzzle.com/img/articleImages/383327-28127-53.jpg

    Demerits of inorganic fertilizers
    •  Soil acidification
    • Water pollution
    • Contamination with impurities
    • Fertilizer dependency
    •  Trace mineral depletion
    • Over fertilization
    • High energy consumption
    • Contribution to climate change
    • Impacts on mycorrhizas
    • Lack of long-term sustainability

     Nitrogenous Fertilizer

    The nitrogen in CAN is made up by the slow ammonium nitrogen and the fast nitrate nitrogen at equal ratio, therefore, it can be applied for both top dressing and basic fertiliza­tion for any kind of soil types and vegetation. The dolomite content with the nitrogen reduces the sourness of the soil, so it is spe­cifically recommended for treating sour soils. Calcium (magnesium) improves the soil structure, as its clay/humin complexes make it crumbly (water, heat and air retaining capacity of the soil will be better due to porosity), and increases its fertility. It increases the absorption and utilization of other nutrients through improving the ion balance.

                                                           Market value

    Nitrogenous Fertilizers Market
    Nitrogenous Fertilizers Market Value, by Geography, 2011-2018 ($Million)

    In 2012, the global nitrogen fertilizers market generated a value of $98,627.9 million and is anticipated to grow at a CAGR of 2.2% by 2018. The market is led by urea by type with the fastest growing CAGR and market share. The market was led by Asia-Pacific by geography in 2012; this trend is expected to continue till 2018.The ammonium nitrate market was led by Europein 2012.