Pump And Classification Of Pump

What is Pump?

         Pump is a very common device useful in all the industries. Pump is device that moves fluids (liquids, gases) or sometimes slurries by mechanical action.

CLASSIFICATION OF PUMP

      Generally pumps are classified by their mechanical configuration and their working principle.
 Pumps are classified mainly in two categories :

1. DYNAMIC PUMPS :

                        Dynamic Pump is a kinetic machine in which energy is continuously imparted to the pumped fluid by means of rotating impeller, propeller or rotor, in contrast to a positive displacement pump in which a fluid is moved by trapping a fixed amount of fluid and forcing the trapped volume into the pump's discharge. Centrifugal Pumps are the most common type of pumps used in industries.


2. POSITIVE DISPLACEMENT PUMPS :

                       Positive displacement pump has an expanding cavity on suction side and a decreasing cavity on the discharge side. In these types of pumps liquid flows into the pump as the cavity on the suction side expands and liquid flows out of the discharge as the cavity collapses. The volume is a constant throughout each cycle of operation. As shown above positive displacement pump can be divided into two types : Reciprocating Type and Rotary Type Pump. Piston pump and Diaphragm Pump are the examples of Reciprocating Type Pump. Gear Pump, Lobe pump, Vane Pump , Screw Pump and Plunger Pump are the examples of Rotary Type Pump.

                   

                       



        

Significance of Wet Crude Oil Separators

*Significance* :

--> In Oil & Gas Separation Units, Separator designates as *Pressure Vessel* Which is used for separating Either Oil & Gas or Oil, Gas & Water. Separator can be used as two phase as well as three phase separation.  

--> Separators may have following internals for effective separations:

A. Vanetype Inlet Device 
B. Demister
C. Vanepack
D. Calming Baffles
E. Coalescing Plate Pack
F. Defoaming Pack 
G. Online Sandjetting System
H. Weir Plate 

--> Typical Separator Sketch:  

           

           A. Vane type Inlet Device 

At the inlet of the vessel, the Vane type Inlet Device  functions as the first step in separating the bulk liquids from the gaseous phase. The Vane type Inlet Device also assures a more even flow distribution at the upstream side of the vessel.

B & C. Wiremesh Demister + Vanepack 

The vane type outlet device (Vane Pack) functions as a coalescer for small droplets carried by the gas. These droplets coalesce on the vanes and are removed from the gaseous phase. The surface area selected for gas/liquid separation has a corresponding K value . A wire mesh demister is installed upstream of the vane pack. This demister will act as an agglomerator during design flow and will take over the separation when the flow is below the turndown range of the vane pack.

D. Calming Baffles

Calming baffles are installed to dampen the liquid movement inside the vessel and to assure an optimal flow distribution across the vessel.

E. Coalescing Plate Pack

The Coalescing Plate Pack is used to enhance the separation of oil and water (and gas). Small droplets or bubbles of the different phases coalesce on the plates, forming larger droplets or bubbles that more easily settle by gravity, thereby enhancing the separation performance of the vessel.

F. Defoaming pack

The Defoaming pack is installed on top of the Coalescing Plate Pack to break down the foam bubbles.

G. Online sand jetting system

The Online sand jetting system is installed on the bottom of the vessel consists of 6 sand jetting sections. Each section consists of a gutter, nozzle banks, an internal discharge pipe, and a water supply pipe. A section should individually be operated to minimize disturbances at the oil/water interface and to minimize the required flow rate of supply water. The spray nozzles are aiming at the places where the sand will settle.

H. Weir Plate 

The Weir Plate is designed to run the full width of the separator. This helps to minimize unwanted surges within the unit that are deleterious to efficient functioning of the separator. This is most important when skim pipes are utilized or if flow rates may change in the future  

Calculation Of MB With Chemical Reaction With Example

 A small scale semibatch reactor unit produces 5000 kg/day of Chloroacetic acid. It uses 4536kg/day of chlorine gas. But 263kg/day of dichloro acetic acid also formed. Here we will find the  percent conversion, percent yield of Chloroacetic acid and selectivity.

Reactions :

   

       CH₃COOH + Cl₂  ------- ClCH₂COOH + HCl

       CH₃COOH + 2Cl₂ ------- Cl₂CHCOOH + 2HCl 

SOLUTION :

 Number of Cl₂ Charged = 4536 / 71

                                           = 63.9 kmol

Number of moles of  Cl2 used for 1st reaction

                                                         = 5000 / 94.5

                                                         = 52.9 kmol

Number of moles of Cl2 used for 2nd reaction
                                                         = (263 / 129) * 2
                                                         = 4.1 kmol

Percent Conversion
                          = Total Cl2 used / Total Cl2 taken
                          = (52.9+4.1) / 63.9 * 100
                          = 89.2 %

Percent Yield = 52.9 / (52.9 + 4.1) * 100
                           = 92.85%

Selectivity = 52.9 / 4.1 * 100
                  = 12.97