Claims:WE CLAIM:

1) An Electrostatic Agglomeration System for particulate emission control, said agglomeration system comprising:
• an inlet for facilitating introduction of a gas stream within said agglomeration system;
• a charging chamber in fluid communication with said inlet to enable said gas stream entering said inlet to flow through said charging chamber, said charging chamber comprising:
? a first grid having a plurality of positive charging cells with each positive charging cell positively charging particulate matter in said gas stream flowing therethrough; and
? a second grid having a plurality of negative charging cells with each negative charging cell negatively charging particulate matter in said gas stream flowing therethrough;
• a mixing zone in fluid communication with said charging chamber to enable mixing and coalescing of positively charged particulate matter in said gas stream exiting said first grid with negatively charged particulate matter in said gas stream exiting said second grid, to form one or more agglomerates; and
• an outlet for facilitating exit of said one or more agglomerates from said agglomeration system.

2) The electrostatic agglomeration system as claimed in claim 1, wherein:
• said plurality of positive charging cells are arranged in a honey comb structure oriented along the length of said charging chamber with said each positive charging cell having an hexagonal cross-section; and
• said plurality of negative charging cells are arranged in a honey comb structure oriented along the length of said charging chamber with said each negative charging cell having an hexagonal cross-section.

3) The electrostatic agglomeration system as claimed in claim 1, wherein:
• said each positive charging cell comprises a positive charging electrode axially disposed along the length thereof to apply a positive electric field corona discharge to said gas stream flowing therethrough for positively charging particulate matter in said gas stream; and
• said each negative charging cell comprises a negative charging electrode axially disposed along the length thereof to apply negative electric field corona discharge to said gas stream flowing therethrough for negatively charging particulate matter in said gas stream.

4) The electrostatic agglomeration system as claimed in claim 3, wherein:
• a first end of said positive charging electrode is connected to a positive power insulator frame installed in a top portion of said charging chamber above said first grid and a second send of said positive charging electrode is connected to a support insulator frame installed in a bottom portion of said charging chamber; and
• a first end of said negative charging electrode is connected to a negative power insulator frame installed in a top portion of said charging chamber above said second grid and a second send of said negative charging electrode is connected to the support insulator frame installed in the bottom portion of said charging chamber.

5) A electrostatic agglomeration system for particulate emission control, said agglomeration system comprising:
• an inlet for facilitating introduction of a gas stream within said agglomeration system;
• a charging chamber in fluid communication with said inlet to enable said gas stream entering said inlet to flow through said charging chamber;
• a plurality of positive charging cells and a plurality of negative charging cells disposed in said charging chamber for positively charging and negatively charging particulate matter in said gas stream flowing there through, respectively, wherein each positive charging cell and each negative charging cell is arranged as a pair to form a plurality of positive-negative charging cell pairs in said charging chamber;
• a mixing zone in fluid communication with said charging chamber to enable mixing and coalescing of positively charged particulate matter with the negatively charged particulate matter in the gas stream exiting said charging chamber, to form one or more agglomerates; and
• an outlet for facilitating exit of said one or more agglomerates from said agglomeration system.

6) The electrostatic agglomeration system as claimed in claim 5, wherein:
• said plurality of positive charging cells are arranged in a honey comb structure oriented along the length of said charging chamber with said each positive charging cell having an hexagonal cross-section; and
• said plurality of negative charging cells are arranged in a honey comb structure oriented along the length of said charging chamber with said each negative charging cell having an hexagonal cross-section.

7) The electrostatic agglomeration system as claimed in claim 5, wherein:
• said each positive charging cell comprises a positive charging electrode axially disposed along the length thereof to apply a positive electric field corona discharge to said gas stream flowing there through for positively charging particulate matter in said gas stream; and
• said each negative charging cell comprises a negative charging electrode axially disposed along the length thereof to apply negative electric field corona discharge to said gas stream flowing there through for negatively charging particulate matter in said gas stream.

8) The electrostatic agglomeration system as claimed in claim 3 or 7, wherein DC voltage corresponding to said positive and negative electric fields is equivalent to corona inception voltage, and is in the range of 20 KV to 25 KV.

9) The electrostatic agglomeration system as claimed in claim 3 or 7, wherein said negative charging electrode and said positive charging electrode is charged through high frequency charging generated by at least one of MOSFET and IBGT based high frequency transformer having output frequency in the range of 20 KHz to 25 KHz.

10) The electrostatic agglomeration system as claimed in claim 3 or 7, wherein said positive charging electrode and said negative charging electrode is a Mobius electrode.

11) The electrostatic agglomeration system as claimed in claim 1 or 5, wherein said charging chamber has a rectangular cross-section.

12) The electrostatic agglomeration system as claimed in claim 1 or 5, wherein said outlet is further connected to a dust collection system, said dust collection system comprises at least one cyclone.
, Description:FIELD OF INVENTION
The present invention is related generally to emission control for pollution abatement.
More particularly, the present invention is related to particulate emission control systems for emission control of particulate matter released by combustion of fuels.

BACKGROUND
Global warming has been recognized as one of the biggest challenges before mankind. To prevent global warming, more and more countries have agreed to stricter emissions standards for curbing global pollution. World over renewable energy is now being encouraged as an alternative to fossil fuels to meet energy demands. World is slowly shifting from fossil fuels to renewable energy to reduce the impact of carbon dioxide (CO2¬) emission on the environment due to burning of fossil fuels. In developing countries biomass fuels such as charcoal, harvest/agricultural residues, wood materials, algae etc. are commonly used as energy resources. In many parts of the world, particularly South East Asia and other such places having tropical/sub-tropical climate, different kinds of palm trees are widely found and palm waste is therefore used as an economic biomass fuel to reduce impact of CO2 emission on the environment. One of the most important advantages attributed to the use of renewable fuels such as biomass is its low cost and widespread distribution. However, burning of biomass fuels is also frequently cited as one of the main reasons for pollutant gases to enter the atmosphere. Burning of biomass fuels typically causes emission of gases containing dust particulate matter of the size of a few microns, which can cause severe health effects such us lung cancer, and chronic lung and heart diseases. The effect of dust particulate matter goes beyond risks to human health to even affect the weather and reduce visibility.

Decentralized systems for heat and power applications such as coal based power plants emit gaseous pollutants having significant particulate matter. Various dust collection systems with different pollution control technologies have been developed for targeted pollutants, the selection of which depends on source conditions and the control efficiency required. Some of the commonly used dust collection systems for particulate emission control include Cyclones (or multi-clones), Electrostatic precipitators (wet and dry types), Wet scrubbers, Fabric filters, etc.
• Cyclones are typically used for removal of large, coarse size particulate matter of 50 microns (µm) or larger. Efficiency of a cyclone is dependent on the particle diameter and increases exponentially with the size of particle diameter and increased pressure drop through the cyclone.
• Electrostatic precipitators are relatively large, low velocity dust collection devices that work on the principle of particle charging the polluted air as it passes through, and are often configured as a series of collecting plates wherein dust resistivity plays a vital role in collection efficiency.
• Wet scrubbers are devices wherein polluted air is passed through a scrubbing solution, typically a mixture of water and other compounds, allowing the particulate matter to attach to the liquid molecules. However wet scrubbers produce a wastewater stream that will likely require treatment before reuse or discharge and also require large foot print area for installation.
• Fabric filters also known as bag houses work on the principle of filtration, wherein dust laden air is passed through a bag shaped fabric filter leaving the particulate matter to collect on the outer surface of the bag and allowing the clean air to pass through. However the size of equipment which employs fabric filters becomes large with the decrease in particle size and density.

There have been several endeavors to develop pollution control technologies for particulate emission control. US Patent nos. 4352681, 4588423 and 5591253 are related to electrostatic separators that use internal corona charging methods for imparting a charge on the particles to enhance the separation process. However, a disadvantage with using internal corona discharge in the cyclone as described in these prior arts is that the corona discharge generates a corona wind that is difficult to be maintained symmetrical and uniform in a dust environment. In addition, the corona discharge adds an undesirable turbulence in situations where a streamlined flow is desired.

Korean publication KR20010068251 is related to a cyclone dust collector of electrostatic centrifugal separation type that uses an electrical repulsive force due to the preliminary charge and the high voltage of fine dust particles. However, the cyclone dust collector consists of extra feedback device that collects the separated dust particles and feeds them back together with the dust particles from the preliminary charge to a centrifugal separation part, thereby adding to the structural and operational complexities of the collector.

US Patent no. 6482253 is related to methods and apparatus for charging powders using either a direct current or an alternating high voltage field along with a corona discharge to produce particles with a desired polarity. The apparatus consists of single or multiple conduits that are divided into an even number of multiple chambers that can operate with each opposing chamber having either a different or similar polarity. Powder entering the conduits is electrically charged or polarized. Upon exiting the separate chambers, the individual polarized particles of the powder combine to form larger particles when the opposing chambers have different polarities, or would continue in a repelled state until they lose their charge by contact, triboelectric conditions or normal charge decay, if the polarities were similar in each chamber. However this prior art mentions an over generalized concept for pre-charging powder particles and fails to provide specific operational modalities for handling combusted biomass particles, and in particular particles generated from processes burning biomass like palm wastes, baggase, ground nut shell, coffee spent and other such fibrous biomass residues that mainly leads to the formation of fine and ultrafine particles with a good amount of particles having diameters below 1 µm in the exhaust. At such particulate sizes, applying the right amount of charge to comply with the environment norms of a particular region, and also at the same time keeping the process energy and cost efficient is a major challenge. This prior art does not mention any specific structural arrangement that can charge the particles in the right amount for efficient combining of the individual polarized particles of the powder exiting the chambers.

To overcome disadvantages of the aforementioned dust collection systems including different pollution control technologies and prior arts, there is a need for a particulate emission control system that employs dry systems that can apply the right amount of charge on the particulate matter in pollutant gases released by combustion of biomass fuels, to enable trapping of ultrafine particulate emissions of fibrous biomass and at the same time adhere to different emission ranges, while having lower footprint area and lower maintenance to enable the system to be deployed in small and medium scale industries.

OBJECTS
Some of the objects of the present invention, which at least one embodiment herein satisfies, are as follows.

An object of the present invention is to provide a system for particulate emission control of pollutant gases released by combustion of biomass fuels.

Another objection of the present invention is to provide a system for particulate emission control that charges particulate matter in the pollutant gases in the right amount to enable effective control of particulate matter.

Another object of the present invention is to provide a system for particulate emission control that can enable trapping of ultrafine particulate emissions of fibrous biomass.

Another object of the present invention is to provide a system for particulate emission control that is compatible to a wide range of fibrous biomass and can adhere to different emission ranges thereof.

Another object of the present invention is to provide a system for particulate emission control that does not generate any effluents in the process of controlling particulate emission.

Another object of the present invention is to provide a system for particulate emission control that has a low footprint area and low maintenance.

Another object of the present invention is to provide a system for particulate emission control that incurs low capital and operating costs, and can easily be retrofitted.

Other objects and advantages of the present invention will be more apparent from the following description which is not intended to limit the scope of the present invention.

SUMMARY
In accordance with an embodiment of the present invention, there is provided an Electrostatic Agglomeration System for particulate emission control. The system comprises an inlet, a charging chamber, a mixing zone and an outlet. The inlet facilitates introduction of a gas stream within the agglomeration system. The charging chamber is in fluid communication with the inlet to enable the gas stream entering the inlet to flow through the charging chamber, wherein the charging chamber comprises a first grid having a plurality of positive charging cells with each positive charging cell positively charging particulate matter in the gas stream flowing therethrough, and a second grid having a plurality of negative charging cells with each negative charging cell negatively charging particulate matter in the gas stream flowing therethrough. The mixing zone is in fluid communication with the charging chamber to enable mixing and coalescing of positively charged particulate matter in the gas stream exiting the first grid with negatively charged particulate matter in the gas stream exiting the second grid, to form one or more agglomerates. The outlet facilitates exit of the one or more agglomerates from the agglomeration system.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
The present invention will now be described with the help of the accompanying drawing, in which:

Figure 1a illustrates a perspective view of an electrostatic agglomeration system in accordance with an embodiment of the present invention;

Figure 1b illustrates a perspective view of a chamber of the electrostatic agglomeration system in accordance with the embodiment of figure 1a;

Figure 1c illustrates a perspective view of an electrode deployed in the electrostatic agglomeration system in accordance with the embodiment of figure 1a;

Figure 2 illustrates a filtration system having the electrostatic agglomeration system coupled with high an efficiency Cyclone in accordance with the present invention;

Figure 3 is a graphical representation illustrating the emission and pressure drop across the filtration system according to figure 2, with respect to varying velocities at Cyclone inlet with and without particle charging;

Figure 4 is a graphical representation showing the emission control achieved by the filtration system according to figure 2, for varying inlet dust loads for palm ash;

Figure 5 is a graphical representation showing the emission control achieved by the filtration system according to figure 2, for different types of ash;

Figure 6 is a graphical representation showing the emission without agglomeration and with agglomeration post Cyclone;
Figure 7 is a graphical representation depicting the effect of input power on overall efficiency in the filtration system according to figure 2.

DETAILED DESCRIPTION
Biomass fuel combustion for heat and power applications typically causes emission of gaseous pollutants having particulate matter of the size of a few microns. Various dust collection systems with different pollution control technologies such as Cyclones, Electrostatic precipitators, Wet scrubbers, Fabric filters, etc., have been developed for particulate emission control. However, cyclones are typically used for removal of large, coarse size particulate matter of 50 µm or larger; electrostatic precipitators are relatively large, low velocity dust collection devices that are configured as a series of collecting plates for particle charging present in the polluted air/gas, where dust resistivity plays a vital role in collection efficiency; wet scrubbers produce a wastewater stream that require treatment before reuse or discharge and also require large foot print area for installation; and fabric filters cause the size of the equipment employing the fabric filters to become large with the decrease in particle size and density.

Prior art systems developed for particulate emission control suffer from various defects such as asymmetrical corona discharge, complex structure, inability to handle particles generated from combustion of biomass fuels, and inability of applying the right amount of charge on the particulate matter in the pollutant gases released from combustion of biomass fuels.

To overcome the aforementioned disadvantages of existing dust collection systems and prior art pollution control technologies, the present invention envisages an electrostatic agglomeration system for particulate emission control that can apply the right amount of charge on the particulate matter in pollutant gases released from combustion of biomass fuels, to enable trapping of ultrafine particulate emissions of fibrous biomass, and at the same time has low footprint area and low maintenance to enable the system to be deployed in small and medium scale industries.

The electrostatic agglomeration system in accordance with the present invention will now be described with reference to the embodiments shown in the accompanying drawings. The embodiments do not limit the scope and ambit of the disclosure. The description relates purely to the examples and preferred embodiments of the disclosed method and its suggested applications.

The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.

Referring to figure 1a, a perspective view of an electrostatic agglomeration system in accordance with an embodiment of the present invention, is illustrated. The electrostatic agglomeration system (1000) comprises an inlet (1011), a charging chamber (1010), a mixing zone (1012), and an outlet (1013). The inlet (1011) facilitates introduction of a gas stream released by the combustion of biomass fuels within the agglomeration system. The charging chamber (1010) is in fluid communication with the inlet (1011) whereby the gas stream entering the inlet (1011) flows through the charging chamber (1010). The gas stream is typically formed by burning fibrous biomass such as palm wastage, baggase, groundnut shell, coffee spent combustion particles and biomass fuels.

Referring to figure 1b, a perspective view of the charging chamber of the electrostatic agglomeration system in accordance with the embodiment of figure 1a, is illustrated. The charging chamber (1010) comprises at least two grids, typically denoted by a first grid (1001) and a second grid (1002). The gas stream entering the charging chamber (1010) gets divided into two streams, a first gas stream (1011a) that flows through the first grid (1001), and a second gas stream (1011b) that flows through the second grid (1002). The first grid (1001) comprises a plurality of positive charging cells (1004) each of which positively charges dust particulate matter in the gas stream i.e. the first gas stream (1011a), flowing therethrough. The second grid (1002) comprises a plurality of negative charging cells (1005) each of which negatively charges dust particulate matter in the gas stream i.e. the second gas stream (1011b), flowing therethrough. Both the positive charging cells (1004) in the first grid (1001) as well as the negative charging cells (1005) in the second grid (1002) are arranged in a honey comb structure packing oriented along the length of the charging chamber (1010), with each positive charging cell (1004) and each negative charging cell (1005) having an hexagonal cross-section.

A positive charging electrode (1007) is axially disposed along the length of each positive charging cell (1004) to apply positive electric field to the gas stream i.e. the first gas stream (1011a) flowing through the cell (1004), whereby the particulate matter in the first gas stream (1011a) are positively charged by the corona discharge from the positive electrode (1007). Similarly, a negative charging electrode (1008) is axially disposed along the length of each negative charging cell (1005) to apply negative electric field to the gas stream i.e. the second gas stream (1011b) flowing through the cell (1005), whereby the particulate matter in the second gas stream (1011b) are negatively charged by the corona discharge from the negative electrode (1008).

One end or a first end of each positive charging electrode (1007) is connected to a positive power insulator connecting frame (1009a) installed in a top portion of the charging chamber (1010) above the first grid (1001) and a second send of the positive charging electrode (1007) is connected to a support insulator frame (not particularly shown) installed in a bottom portion of the charging chamber (1010). Similarly, one end or a first end of each negative charging electrode (1008) is connected to a negative power insulator connecting frame (1009b) installed in a top portion of the charging chamber (1010) above the second grid (1002) and a second send of the negative charging electrode (1008) is connected to the support insulator frame (not particularly shown) installed in a bottom portion of the charging chamber (1010). The support insulator frame is typically provided for mechanical support to the electrodes.

The connection of the electrodes (1007, 1008) to the power insulator frames (1009a, 1009b) and to the support insulator frame ensures that each electrode passes axially through the center portion along the length of each cell (1004, 1005) with a predetermined electric clearance maintained between each electrode (1007, 1008) and the walls of each cell (1004, 1005). This enables each electrode to be activated for a predetermined treatment time to maintain the desired electric field (KV/cm) and the corona inception voltage in each cell, resulting in a precise amount of electric field (KV/cm) being applied to the gas stream passing through the cells, and thereby ensuring that particulate matter in the gas stream are charged in the right amount.

In accordance with an embodiment, each of the positive and negative electrodes (1007, 1008) is a Mobius electrode as shown in Indian Design registration no. 268438 in the name of this Applicant. Referring to figure 1c, a perspective view of the Mobius electrode (1007, 1008) disposed in each positive and negative charging cell (1004, 1005), is illustrated. The DC voltage corresponding to the positive and negative electric fields generated by each Mobius electrode is equivalent to corona inception voltage, and is in the range of 20 KV to 25 KV. Typically the electrodes are charged through high frequency charging generated by, metal oxide semiconductor field effect transistor (MOSFET) or insulated gate bipolar transistor (IBGT), based high frequency transformer having output frequency in the range of 20 KHz to 25 KHz.

The positively charged particulate matter in the first gas stream (1011a) exiting the first grid (1001) and the negatively charged particulate matter in the second gas stream (1011b) exiting the second grid (1002) get mixed with each other in the mixing zone (1012), leading to coalescing of the small positively charged and negatively charged particulate matter and forming of agglomerates which are released from the outlet (1013) of the system (1000). The agglomerates may then be passed through a dust collection system such as a cyclone where they can be easily trapped in the filters deployed therein.

The charging chamber (1010) is constructed typically in rectangular shape. It may be appreciated that the shape of the charging chamber is not intended to be limited to be rectangular, and that charging chamber can be constructed to be of various geometrical shapes and sizes.

In accordance with another embodiment, each positive charging cell (1004) and each negative charging cell (1005) is arranged as a pair to form a plurality of positive-negative charging cell pairs in the charging chamber (1010). The positive-negative charging cell pairs are arranged charging chamber (1010) next to each other in the charging chamber (1010), with each positive charging cell (1004) and each negative charging cell (1005) having an hexagonal cross-section.

In accordance with yet another embodiment, a plurality of positive charging cells (1004) are grouped together to form a positive charging section, and a plurality of negative charging cells (1005) are grouped together to form a negative charging section, such that a plurality of positive charging sections and a plurality of negative charging sections are arranged in the charging chamber (1010). The plurality of positive charging sections and negative charging sections are arranged in a honey comb structure packing oriented along the length of the charging chamber (1010), with each positive charging cell (1004) and each negative charging cell (1005) having an hexagonal cross-section.

Referring to figure 2, a filtration system having the electrostatic agglomeration system in accordance with the present invention, is illustrated. The electrostatic agglomeration system (1000) in accordance with the present invention is deployed prior to filtration of pollutant gases in a dust collection system such as a cyclone (2000). The gas stream formed by burning fibrous biomass such as palm wastage, baggase, groundnut shell, coffee spent combustion particles and biomass fuels enters the agglomeration system (1000) through the inlet and get split into two streams between the first and second grids in the charging chamber (1010). The dust particulate matter in the gas stream entering the first grid get positively charged and the dust particulate matter in the gas stream entering the second grid get negatively charged, whereupon the gas streams with the positively and negatively charged particulate matter exit the charging chamber and get mixed in the mixing zone to form agglomerates which then flow out of the outlet.

The agglomerates flowing out of the outlet are then fed to one or more cyclones (2000), wherein the agglomerates get trapped and drop down in the hopper of the cyclone, thereby cleaning the gas stream before being released from the outlet or chimney (2001) of the cyclone. The cleaned gas stream thus flowing out of the chimney (2001) of the cyclone (2000) will be having emission level below 100 mg/nm3.

Referring to figure 3, a graphical representation of the emission and pressure drop across the filtration system according to figure 2 with respect to varying velocities at cyclone inlet with and without particle charging, is illustrated. The graphical representation shows that there is a significant reduction in the emission from the cyclone with increase in cyclone inlet velocity and particle agglomeration.

Referring to figure 4, a graphical representation of emission control achieved by the filtration system according to figure 2 for varying inlet dust loads for palm ash, is shown. In general, emission levels increase with increase in dust loads.

Referring to figure 5, a graphical representation of the emission control achieved by the filtration system according to figure 2, for different types of ash, is shown. The graphical representation exhibits emission control for particulate matter generated by combustion of different fuels, thereby demonstrating that the electrostatic agglomeration system can be used upstream of a filtration device, in this case the cyclone, for achieving satisfactory results for varying fuel types such as spent wash, palm and coal.

Referring to figure 6, a graphical representation of the emission without agglomeration and with agglomeration, is shown. The emission is significantly improved and is cleaner with the use of the electrostatic agglomeration system in accordance with the present invention.

Referring to figure 7, a graphical representation of the effect of input power in the filtration system according to figure 2, is depicted. The input power includes negative, neutral + negative and negative + positive in the electrostatic agglomeration system. The use of negative and positive input power has the maximum impact on the efficiency of the electrostatic agglomeration system.

The electrostatic agglomeration system in accordance with the present invention applies the right amount of charge on the particulate matter in pollutant gases released by combustion of biomass fuels, leading to trapping of ultrafine particulate matter emissions of fibrous biomass. The electrostatic agglomeration system in accordance with the present invention is a dry system that has a low footprint area and low maintenance whereby the system to be deployed in small and medium scale industries.

Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the invention to achieve one or more of the desired objects or results.

Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the invention as it existed anywhere before the priority date of this application.

The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the invention, unless there is a statement in the specification specific to the contrary.

The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.