Patent Publication Number: US-2017369791-A1

Title: Crude Quality Enhancement by Simultaneous Crude Stabilization, Sweetening, and Desalting Via Microwave Assisted Heating

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority from U.S. Provisional Application No. 62/355,683 filed Jun. 28, 2016, and titled “CRUDE QUALITY ENHANCEMENT BY SIMULTANEOUS CRUDE STABILIZATION, SWEETENING, AND DESALTING VIA MICROWAVE ASSISTED HEATING.” For purposes of United States patent practice, this application incorporates the contents of the Provisional Application by reference in its entirety. 
    
    
     BACKGROUND 
     Field of the Disclosure 
     The present disclosure generally relates to the processing of crude oil. More specifically, embodiments of the disclosure relate to crude quality enhancement using microwaves. 
     Description of the Related Art 
     Elemental sulfur and sulfur compounds are naturally present in many petroleum crude oils. The amount of sulfur varies over a wide range; for example, crude oil from Texas contains about 0.1 weight percent sulfur, whereas crude oil from Saudi Arabia and Kuwait contains about 3 weight percent sulfur to 5 weight percent sulfur. Crude oil may also include a wide variety of sulfur-containing compounds. Such sulfur-containing compounds range from hydrogen sulfide, which is a gas at room temperature, to organosulfur compounds that vaporize at over 1000° F. 
     Sulfur compounds are undesirable because of their odors and because sulfur compounds such as hydrogen sulfide are corrosive. The corrosive nature of sulfur compounds contributes significantly to the costs of construction, operation and maintenance of a petroleum refinery. Additionally, sulfur compounds may cause problems in gasoline engines and can contribute to environmental pollution. Sulfur in crude oil can generate hydrogen sulfide and other sulfur containing gases during transportation and, consequently, increase the difficulty of such operations. 
     SUMMARY 
     When crude petroleum is processed in an oil refinery, one of the steps is the separation of the crude into various products based on boiling points. The unit typically used for this separation is a distillation column operated at atmospheric pressure and is commonly referred to as the crude still. Such oil refinery processes may yield a variety of useful fuels and desirable petroleum products, such as lower-boiling gasoline, middle distillate fuels such as kerosene and diesel oil, to fuel oil for heating, and higher-boiling waxes and heavy oils such as lubricating oil and asphalt products. The separation of the hydrocarbons also separates the sulfur compounds so that the lower boiling hydrocarbons contain lower-boiling sulfur compounds and higher-boiling hydrocarbons contain higher-boiling sulfur compounds. 
     Many technologies have been developed relating to sweetening and desulfurizing gasolines and other petroleum stocks depending upon the particular type of sulfur compound to be removed. Some technologies for sweetening, desulfurizing, or both include: oxidation reactions, solvent extraction, adsorption, metal catalysis, and hydrodesulphurization. However, most of these technologies are based on conventional refining techniques and have a relatively high cost. Furthermore, these technologies fail to sufficiently address the problem of removing sulfur and resulting formed sulfur compounds such as H 2 S. 
     In some embodiments, a method of processing crude oil is provided. The method includes irradiating water at a first temperature with microwaves to produce heated water at a second temperature such that the second temperature is greater than the first temperature. The method further includes providing the heated water to a crude oil stream. The crude oil stream includes a gas phase, an oil phase, and a water phase. The method also includes providing the crude oil stream to a downstream crude oil processing unit. 
     In some embodiments, providing the heated water to the crude oil stream includes directing the heated water at a gas-oil interphase of the crude oil stream. In some embodiments, providing the heated water to the crude oil stream includes directing a first portion of the heated water at a gas-oil interphase of the crude oil stream and directing a second portion of the heated water at an oil-water interphase of the crude oil stream. In some embodiments, the method also includes disrupting an oil-water emulsion using the second portion of the heated water. In some embodiments, the method further includes obtaining the water at the first temperature from the crude oil stream. In some embodiments, the method also includes separating solids from the water before irradiating the water with microwaves to produce the heated water at the second temperature. In some embodiments, the water includes treated water from a water treatment unit of a crude oil processing plant. In some embodiments, the crude oil processing unit includes a high pressure production trap (HPPT), a low pressure production trap (LPPT), a stabilization unit, a desalter, or a dehydrator. In some embodiments, the method includes producing a gas stream and a separated crude oil stream from the crude oil processing unit. Additionally, in some embodiments, the method includes boiling an H 2 S component of the crude oil stream using the heated water and, in some embodiments, boiling light end components of the crude oil stream using the heated water. In some embodiments, the microwaves have a frequency of 915 MHz. In some embodiments, the second temperature is 194° F. to 250° F. 
     In some embodiments, a system is provided that includes a pipe configured to transport a crude oil stream to a crude oil processing unit and a microwave unit upstream from the crude oil processing unit and coupled to the pipe. The microwave unit is configured to receive water at a first temperature from the crude oil stream and irradiate the water to produce heated water at a second temperature, wherein the second temperature is greater than the first temperature. The outlet of the microwave unit is coupled to an inlet of the pipe such that the inlet is configured to direct the heated water at an oil-gas interphase of the crude oil stream. In some embodiments, the system further includes a solids separator coupled to the microwave unit, the solids separator configured to separate solids from the water before the microwave unit receives the water. In some embodiments, the crude oil processing unit includes a high pressure production trap (HPPT), a low pressure production trap (LPPT), or a stabilization unit. In some embodiments, the crude oil stream is a first crude oil stream having a first composition and the crude oil processing unit is configured to output a second crude oil stream having a second composition. In some embodiments, the system includes a crude oil analyzer configured to determine at least one parameter of the second crude oil stream and a controller. The controller is configured to receive the at least one parameter from the crude oil analyzer, compare the at least one parameter to a respective at least one threshold value and modify a power of the microwaves based on the comparison. In some embodiments, the at least one parameter includes H 2 S content, salt content, or Reid vapor pressure. 
     In some embodiments, a system is provided that includes a pipe configured to provide a crude oil stream to a crude oil processing unit and a microwave unit upstream of the crude oil processing unit and coupled to the pipe. The microwave unit is configured to irradiate water at a first temperature to produce heated water at a second temperature, wherein the second temperature is greater than the first temperature. An outlet of the microwave unit is coupled to a first inlet of the pipe such that the first inlet is configured to direct a first portion of the heated water at an oil-gas interphase of the crude oil stream. The outlet of the microwave unit is further coupled to a second inlet of the pipe such that the second inlet configured to direct a second portion of the heated water at an oil-water interphase of the crude oil stream. In some embodiments, the water includes treated water from a water treatment unit. In some embodiments, the crude oil processing unit includes a desalter or a dehydrator. In some embodiments, the crude oil stream is a first crude oil stream having a first composition and the crude oil processing unit is configured to output a second crude oil stream having a second composition such that the crude oil processing unit is configured to output a second crude oil stream having a second composition. In some embodiments, the system includes a crude oil analyzer configured to determine at least one parameter of the second crude oil stream and a controller configured to receive the at least one parameter from the crude oil analyzer, compare the at least one parameter to a respective at least one threshold value, and modify a power of the microwaves based on the comparison. In some embodiments, the at least one parameter includes H 2 S content, salt content, or Reid vapor pressure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram of a prior art crude oil stripping operation; 
         FIG. 2  is a schematic diagram of a crude oil processing operation using microwave heating in accordance with an example embodiment of the disclosure; 
         FIG. 3  is a schematic diagram of a first configuration with a microwave unit in accordance with an example embodiment of the disclosure; 
         FIG. 4  is a schematic diagram of a second configuration with a microwave unit in accordance with another example embodiment of the disclosure; 
         FIG. 5  is a schematic diagram of a crude oil processing operation using microwave heating and a control system in accordance with an example embodiment of the disclosure; 
         FIG. 6  is a schematic diagram of a crude oil processing operation using microwave heating and a control system in accordance with another example embodiment of the disclosure; 
         FIG. 7  is a block diagram of a gas-oil separation process having one or more microwave units in accordance with an example embodiment of the disclosure; 
         FIG. 8  is a flowchart of a process for processing crude oil using microwaves in accordance with an embodiment of the disclosure; and 
         FIG. 9  is a flowchart of a process for processing crude oil using microwaves in accordance with another embodiment of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure will now be described more fully with reference to the accompanying drawings, which illustrate embodiments of the disclosure. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the illustrated embodiments. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. 
     Embodiments of the disclosure include the use of microwave heating to promote the separation of components of crude oil, such as performed in a crude oil processing plant. In some embodiments, microwaves may be used to heat a crude oil stream to promote the separation of sulfur (for example, H 2 S) and light end components from the crude oil stream. In such embodiments, the microwaves may be used to provide interphase heating between the gas phase and the oil phase of the crude oil stream. In some embodiments, microwaves may be used to heat a crude oil stream to promote the separation of water, salt, or both from the crude oil stream. In such embodiments, the microwaves may be used to provide interphase heating between the oil phase and the water phase of the crude oil stream. 
     In some embodiments, microwave heating may be used to heat the interphase between the gas phase and the oil phase of the crude oil. In some embodiments, microwave heated water may be directed at the gas-oil interphase of a crude oil stream to promote the separation of sulfur components and light end components. In such embodiments, the gas-oil interphase heating may promote the separation of sulfur (for example, H 2 S) and light end components, as the composition of the crude oil at the gas-oil interphase includes such components having lower-boiling components than other components of the crude oil. In some embodiments, the gas-oil interphase heating may provide sufficient heating to boil the sulfur components (for example, H 2 S) and light end components while heavier components remain in the liquid phase. In some embodiments, the gas-oil interphase heating may provide heating to promote the separation of sulfur (for example, H 2 S) and light end components in a downstream processing unit (for example, a stabilization unit). 
     In some embodiments, microwave heating may be used to heat the interphase between the oil phase and the water phase of the crude oil. In some embodiments, microwave heated water may be directed at the oil-water interphase of a crude oil stream to promote the separation of water and salt. In such instances, the oil-water interphase heating may disrupt the emulsion present in the oil-water interphase. The disruption of the emulsion may promote the coalescence of larger water droplets that settle to the bottom of the crude oil stream via gravity. The gravity separation of the larger water droplets facilitates the separation of salt dissolved in the water phase of the crude oil. In some embodiments, the oil-water interphase heating may provide heating to promote the separation of water, salt, or both in a downstream processing unit (for example, a desalter). 
     Advantageously, crude oil processing using the microwave heating techniques described in the disclosure may result in improved economics and operability of a crude oil processing plant, such as by reducing energy costs, maintenance costs, and capital costs. For example, as described herein, crude oil processing using microwave heating in the manner described in the disclosure may reduce or eliminate the energy requirements of a separation unit (for example, a stabilization unit) of a crude oil processing plant. In another example, crude oil processing using microwave heating may eliminate the use of a stabilization unit if the separation achieved by the microwave heating meets or exceeds a crude oil specification. 
       FIG. 1  depicts a prior art crude oil stabilization operation  100  (also referred to as a crude oil “stripping operation”) of a crude oil processing plant that has associated operational and capital costs as described infra. As shown in  FIG. 1 , a stabilizer tower  102  may receive a crude oil feed stream  104  and output a gas stream  106  and a stabilized crude oil stream  108 . The feed stream  104  may be heated via a heated stream  110  produced by a heat source  112  (for example, steam or a furnace). The heated stream may be or include a portion of the stabilized crude oil stream  108 . 
     The stabilizer tower  102  includes multiple trays  114  which, in combination with the heat from the heated stream  110 , provide for separation of vapor and liquid from the feed stream  104 . The heated stream  110  may be used to generate vaporized crude, depicted as vapor flow  116 , from the feed stream  104 . As shown in  FIG. 1 , the vapor flow  116  is in a countercurrent flow with a downward flowing liquid flow  118  from the feed stream  104  and condensed crude vapors. As the heating occurs at the bottom of the stabilizer tower  102 , the temperature profile in the stabilizer tower  102  is greatest at the bottom of the tower  102  (at around 175° F.) to lowest at the top of the tower  102  (at around 150° F.). The temperature profile promotes the separation of H 2 S and light end components from the crude oil feed stream  104 . Each of the trays  114  enables separation of the feed stream  104  to occur via vaporization and condensation between the vapor flow  116  and liquid flow  118 . As the vapor flow  116  flows to the top of the stabilizer tower  102 , the vapor composition includes increasing concentrations of H 2 S and light end components. The stabilizer tower  102  may be operated at a lesser pressure (for example, in the range of 3 pounds-per-square inch gauge (psig) to 5 psig) to promote the separation of the vapor and liquid. 
     The fuel cost to operate the stabilizer tower  102  using steam as the heat source  112  or a furnace as the heat source  112  may vary according to the capability of the crude oil processing facility. For example, assuming a fuel gas tariff of about $2.5/million British Thermal Units (MMBtu), the annual fuel gas cost to run the prior art crude oil stabilization operation  100  may be in the range of $2M/year to over $20M/year, depending on production rates. Increasing energy efficiency of a crude oil stripping operation may thus reduce fuel gas consumption and operating costs. The prior art crude oil stripping operation  100  may, in addition to having an energy intensive operation, have a high capital cost, a high risk of losing desired product due to unselective separation, and a high cost of maintenance. 
     Other crude oil processing operations, such as desalting, of a crude oil processing plant also have associated operational and capital costs. A crude oil desalting operation may use water (for example, freshwater or wash water) to first mix with the remnant water. The mixing dilutes the salt concentration in the remnant water and results in the formation of an oil-water emulsion. The oil-water emulsion may be disrupted by chemical treatment (for example, a demulsifier), and an electrical treatment (for example, an electrostatic field). For example, the electrostatic field generated in a dehydrator and desalter unit promotes coalescence of small water droplets resulting from the mixing between the remnant water and added water. The formation and subsequent coalescence of the water droplets assists in the settling and thus, separation, of water from the oil using gravity. This separation may be modeled according to Stoke&#39;s law, shown in Equation 1: 
     
       
         
           
             
               
                 
                   Vt 
                   = 
                   
                     
                       1.78 
                       × 
                       
                         10 
                         
                           - 
                           6 
                         
                       
                        
                       
                         ( 
                         
                           Δ 
                            
                           
                               
                           
                            
                           SG 
                         
                         ) 
                       
                        
                       
                         d 
                         2 
                       
                     
                     μ 
                   
                 
               
               
                 
                   ( 
                   1 
                   ) 
                 
               
             
           
         
       
     
     Where Vt is the droplet settling velocity of water, ΔSG is the difference in specific gravity relative to water, d is the droplet diameter in microns, and μ is the viscosity of the continuous phase (that is, the viscosity of the oil). Equation 1 illustrates that heating affects both the specific gravity and viscosity and, consequently, increases the droplet settling velocity Vt. However, although heating decreases the viscosity, oil viscosity is significantly greater than the water viscosity. Thus, heating the crude oil phase may increase the speed of separation of water from the crude oil and, consequently, may increase the separation of salt from the crude oil. 
     With the foregoing in mind,  FIG. 2  depicts crude oil processing operation  200  of a crude oil processing plant using microwave heating in accordance with an example embodiment of the disclosure.  FIG. 2  depicts a microwave unit  202  having a microwave source  204 , a control unit  206 , and a pressure vessel  208 . For example, the crude oil processing operation  200  may be representative of a crude oil stabilization operation. 
     The microwave unit  202  receives a crude oil feed stream  210 . In some embodiments, the feed stream  210  may be dewatered crude oil. As will be appreciated raw crude oil may be a relatively homogenous 3-phase stream of water, oil and gas. In some embodiments, waste water may be separated from the raw crude oil, such as at an upstream facility, before the crude oil is provided to the crude oil stripping operation  200 . 
     The crude oil feed stream  210  may be directly or indirectly heated by microwaves provided by the microwave source  204  of the microwave unit  202 . In some embodiments, the microwave source  204  may provide microwaves having a frequency in the range of about 890 MHz to about 940 MHz or a frequency in the range of about 2400 MHz to about 2500 MHz. In some embodiments, the microwave source  204  may provide microwaves having a frequency of about 915 MHz or about 2450 MHz. In other embodiments, the microwave source  204  may provide microwaves at different frequencies. In some embodiments, the microwave source  204  may be manufactured by Industrial Microwave Systems, LLC, of New Orleans, La., USA. In some embodiments, as described further herein, the microwave source  204  may be used to heat water, and the heated water may be provided to the crude oil feed stream to heat the crude oil. 
     After heating by the microwave unit  202 , the heated crude oil stream  212  may be provided to the pressure vessel  208  for processing. For example, the pressure vessel  208  may be a stabilization unit that operates in a similar manner to the stabilizer tower  102  described supra. Separated gas  214  and stabilized crude oil  216  may exit the pressure vessel  208  and be provided to downstream facilities for further processing. 
     The microwaves from the microwave source  204  may, by directly or indirectly heating the crude oil feed stream  210 , selectively target sulfur-containing components and light end components in the crude oil feed stream  210 . In some embodiments, the microwave unit  202  may be coupled to a pipe transporting the crude oil feed stream and may be positioned relatively close to the pressure vessel  208  so that the separated ELS and light end components may be more effectively removed from the vessel  208 . In other embodiments, as described further in the disclosure, microwave heating of a crude oil stream may be used to promote dehydration, desalting, and other operations of crude oil processing. 
     Some embodiments may include the retrofit or modification of existing microwave systems to provide microwave heating of a crude oil stream. For example, in some embodiments a microwave water cut meter used to measure the water content in crude oil may be retrofitted or modified for use as the microwave unit  202  for microwave heating of the crude oil feed stream  210 . In some embodiments, the microwave unit  202  may be a spool microwave unit that connects via flanges and does not require any vessel for mounting to existing pipe. 
     The control unit  206  may control the amount of microwaves emitted to achieve a desired crude oil specification via a feedback loop. For example, the amount of H 2 S and light end components in the stabilized crude oil  216  may be measured at a sample point  220 , and a signal  222  indicative of the amount of H 2 S and light end components may be provided to the control unit  206  via an electrical circuit. The control unit  206  may provide a control signal  224  to the microwave source  204  to control the power of microwaves irradiating the crude oil feed stream  210 . For example, the control unit  206  may provide a controls signal  224  to increase the power of the microwaves of the microwave source  204  or decrease the power of the microwaves of the microwave source  204 . 
     As shown in  FIGS. 3 and 4  and as described infra, embodiments of the disclosure further include a configurations of the microwave unit and the heated water output from the microwave unit to promote the separation of components (for example, H 2 S and light end components) from the crude oil.  FIG. 3  depicts a first configuration  300  of a microwave unit  301  in accordance with an example embodiment of the disclosure.  FIG. 3  depicts a cross-sectional view of a pipe  302  transporting crude oil composed of gas, oil, and water, as shown by gas phase  304 , oil phase  306 , and water phase  308 . It should be appreciated that the gas phase  304 , oil phase  306 , and water phase  308  are merely illustrative and may not reflect the actual location or distribution of the phases of the crude oil in the pipe  302 . 
     In the example embodiment depicted in  FIG. 3 , a side-stream  310  of the water phase  308  may be drawn from the pipe  302  and provided to a solids separator  312 . In some embodiments, the side stream  310  may constitute in the range of about 1% by volume to about 5% by volume of the crude oil flowing in the pipe  302 . The solids separator  312  may remove particulate solids or other solid contaminants  314  from the water to prevent such solids from interfering with the flow to the microwave unit  301 . The solids separator  312  may also prevent solid contaminants from flowing into the microwave unit  301  and impairing the heating efficiency of the microwave unit  301 . 
     The separated water  316  output from the solids separator  312  may be provided to the microwave unit  301  for irradiation by microwaves to produce heated water  318 . The heated water  318  may then be provided to the crude oil pipe  302 . In some embodiments, the heated water  318  may be heated to a temperature in the range of about 194° F. to about 250° F. In other embodiments, the heated water  318  may be heated to a temperature in the range of about 194° F. to about 250° F. In some embodiments, the temperature of the heated water  318  may be based on the pressure capability of a downstream vessel receiving the crude oil in the crude oil pipe  302 . It should be appreciated that such heating may be localized to the heated water  318  and may be sufficient to heat and, in some instances, boil some components (for example, H 2 S and light end components) of the crude oil. In some embodiments, the microwave unit  301  may have flow chambers having a microwave waveguide that forms a double-ended resonant chamber with multiple radiofrequency (RF) energy reflections. 
     In some embodiments, the heated water  318  may be provided via a non-metallic pipe that couples the outlet of the microwave unit  301  to an inlet  320  of the crude oil pipe  302 . In some embodiments, the inlet  320  of the heated water may be targeted at the oil and gas interphase between the oil phase  306  and the gas phase  304  to direct the heated water  318  at the oil-gas interphase. For example, in such embodiments, the inlet  320  may be located at a level of about 50% to about 60% from the top of the pipe  302 . 
     In some embodiments, the microwave unit  301  may provide microwaves having a frequency in the range of about 890 MHz to about 940 MHz or a frequency in the range of about 2400 MHz to about 2500 MHz. In some embodiments, the microwave unit  301  may provide microwaves having a frequency of about 915 MHz or about 2450 MHz. In other embodiments, the microwave unit  301  may provide microwaves at different frequencies. In some embodiments, the microwave unit  301  may be manufactured by Industrial Microwave Systems, LLC, of New Orleans, La., USA. In some embodiments, the microwave unit  301  may be a retrofit or modification of an existing microwave system. In some embodiments, the microwave unit  301  may be a spool microwave unit that connects via flanges and does not require any vessel for mounting to existing pipe. In some embodiments, the microwave unit  301  may be placed directly in crude oil pipe  302  (in such embodiments, for example, the microwave unit  301  may have an electromagnetic-transparent housing). 
     The configuration  300  illustrated in  FIG. 3  and described supra may provide heating to the top of the oil layer  306  where specific components (for example, H 2 S and light end components) are predominant. In some embodiments, the heat provided by the heated water  318  may be sufficient to boil the some components (for example, H 2 S and light end components) while retaining the heavy ends components in the liquid phases of the crude oil, such that sensible heat exists and no vaporization occurs. In contrast to the embodiment shown in  FIG. 3 , heating via a top position of the pipe  302  may be less effective, as the microwave-heated water must travel from the top of the pipe  302  and through the gas layer  302 , and is farther from the water layer  308  where heating occurs. Advantageously, the configuration  300  shown in  FIG. 3  also leverages the presence of remaining water in the water phase  308  of the crude oil. 
     In some embodiments, for example, the configuration  300  shown in  FIG. 3  may be used to heat a crude oil stream to promote separation of components (for example, H 2 S and light end components) from the crude oil. For example, the configuration shown in  FIG. 3  may be used upstream of a separation unit (for example, a high pressure production trap, a low pressure production trap, a stabilization unit, and the like). In some embodiments, for example, the configuration shown in  FIG. 3  may be used to place a microwave unit at the entrance of a separation unit to heat a crude oil feed stream and promote separation of components from the crude oil. 
       FIG. 4  depicts a second configuration  400  of a microwave unit  401  in accordance with another example embodiment of the disclosure.  FIG. 4  also depicts a cross-sectional view of a pipe  402  transporting crude oil composed of gas, oil, and water, as shown by gas phase  404 , oil phase  406 , and water phase  408 . It should be appreciated that the gas phase  404 , oil phase  406 , and water phase  408  are merely illustrative and may not reflect the actual location or distribution of the phases of the crude oil in the pipe  402 . 
     In contrast to the embodiment depicted in  FIG. 3  and described supra, the embodiment shown in  FIG. 4  includes the use of treated water  410  from a treated water source. For example, a crude oil processing plant may include sources of treated water for different uses, such as for oil processing and as a source for potable water. Consequently, the embodiment shown in  FIG. 4  may be used without a separator and an additional side-stream of water drawn from the crude oil. It should be appreciated that the available of treated water and the distance to the source of treated water may be considerations for use of the configuration depicted in  FIG. 4  as opposed to the configuration depicted in  FIG. 3 . 
     As shown in  FIG. 4 , treated water  410  may be provided to the microwave unit  401  for irradiation by microwaves to produce heated water  412 . The heated water  412  output from the microwave unit  401  may be provided to the crude oil pipe  402 . In some embodiments, the heated water  412  may be heated to a temperature in the range of about 194° F. to about 250° F. In other embodiments, the heated water  318  may be heated to a temperature in the range of about 194° F. to about 250° F. In some embodiments, the temperature of the heated water  318  may be based on the pressure capability of a downstream vessel receiving the crude oil in the crude oil pipe  302 . It should be appreciated that such heating may be localized to the heated water  412  and may be sufficient to heat and, in some instances, boil some components (for example, H 2 S and light end components) of the crude oil. In some embodiments, the microwave unit  401  may have flow chambers having a microwave waveguide that forms a double-ended resonant chamber with multiple radiofrequency (RF) energy reflections. 
     In some embodiments, the heated water  412  may be provided via a non-metallic pipe that couples the outlet of the microwave unit  401  to a first inlet  414  of the pipe  402 . In some embodiments, the first inlet  414  may be targeted at the oil and gas interphase between the oil phase  406  and the gas phase  404 , such that a first portion  416  of the heated water is directed at the oil and gas interphase of the crude oil. For example, in such embodiments, the first inlet  414  may be located at a level of about 50% to about 60% from the top of the pipe  402 . As previously discussed, providing the microwave-heated water at the oil-gas interphase provides localized heating that at the interphase to boil or improve the boiling of those components having lesser boiling points (for example, H 2 S and light end component). 
     Additionally, the outlet of the microwave unit  401  may be coupled to a second inlet  418  of the pipe  402 . In some embodiments, the second inlet  418  may be located at the oil and water interphase between the oil phase  406  and the water phase  408 , such that a second portion  420  of the heated water  412  is directed at the oil and water interphase of the crude oil. The second portion  420  of the heated water  412  may be directed at the oil-water interphase to heat the water phase  408  and promote oil-water separation in subsequent processing units, such as a dehydrator or a desalter. As previously discussed, providing the microwave-heated water  412  at the oil-water interphase promotes the break-up of the emulsion present in the oil-water interphase and formation of larger water droplets that settle to the bottom via gravity, thus further promoting the separation of salt from the oil phase. In some embodiments, the use of the second portion  420  of the heated water  412  may depend on the pipe length, such as the pipe length between the inlet  418  and a subsequent processing unit. 
     In some embodiments, the microwave unit  401  may provide microwaves having a frequency in the range of about 890 MHz to about 940 MHz or a frequency in the range of about 2400 MHz to about 2500 MHz. In some embodiments, the microwave unit  401  may provide microwaves having a frequency of about 915 MHz or about 2450 MHz. In other embodiments, the microwave unit  401  may provide microwaves at different frequencies. In some embodiments, the microwave unit  401  may be manufactured by Industrial Microwave Systems, LLC, of New Orleans, La., USA. In some embodiments, the microwave unit  401  may be a retrofit or modification of an existing microwave system. In some embodiments, the microwave unit  401  may be a spool microwave unit that connects via flanges and does not require any vessel for mounting to existing pipe. 
     The configuration  400  illustrated in  FIG. 4  and described supra may provide heating to the top of the oil phase  406  where specific components (for example, H 2 S and light end components) are predominant. In some embodiments, the heat provided by the heated water  416  may be sufficient to boil the some components (for example, H 2 S and light end components) while retaining the heavy ends components in the liquid phases of the crude oil, such that sensible heat predominantly exists and no vaporization of heavy end components occurs. Additionally, the configuration  400  shown in  FIG. 4  may promote separation of components (for example, water and salt) between the oil phase  406  and the water phase  408 . Here again, the placement of the heated water portions  416  and  420  may be more effective than heating via a top position of the pipe  402 . Further, the configuration  400  shown in  FIG. 4  also leverages the presence of remaining water in the water phase  408  of the crude oil. 
     In some embodiments, for example, the configuration shown in  FIG. 4  may be used to heat a crude oil stream to promote separation of components (for example, H 2 S and light end components) from the crude oil. For example, the configuration shown in  FIG. 4  may be used upstream of a separation unit (for example, a high pressure production trap, a low pressure production trap, a stabilization unit, and the like). Additionally, the configuration shown in  FIG. 4  may be further used to promote separation between the oil phase and water phase of crude oil. For example, in some embodiments, the configuration shown in  FIG. 4  may be used to position a microwave unit at the entrance of a separation unit such as a dehydrator or desalter to promote separation of water, salt, or both from the crude oil. 
     As shown in  FIGS. 5 and 6  and as described infra, embodiments of the disclosure may further include a control system to monitor the crude oil parameters and adjust a microwave unit in response to the monitored crude oil parameters.  FIG. 5  depicts a crude oil processing operation  500  using microwave heating and a control system  502  in accordance with an example embodiment of the disclosure.  FIG. 5  also depicts a crude oil pipe  504 , a mixer  506 , a microwave unit  508 , a pressure vessel  510 , and a solids separator  512 . 
     The crude oil pipe  504  may provide a crude oil stream to the mixer  506 . The mixer  506  may be used, in some embodiments, to promote mixing of the crude oil steam. In some embodiments, the mixer  506  may be eliminated and the operation  500  may not include the mixer  506 . 
     The microwave unit  508  and solids separator  512  may operate in a manner similar to the microwave source and solids separator described supra and illustrated in  FIG. 3 . For example, a side-stream  516  of the water may be drawn from the crude oil pipe  504  and provided to the solids separator  512  for removal of solid contaminants  518  from the water. The solids separator  512  may also prevent solid contaminants from flowing into the microwave unit  508  and impairing the heating efficiency of the microwave unit  508 . The solids separator  512  may output filter water  520 . 
     The filtered water  520  output from the solids separator  512  may be provided to the microwave unit  508  for heating by microwaves. The microwave unit  508  (which, in some embodiments, includes the microwave source) may output heated water  522  which is then provided to the crude oil feed stream via an inlet  524  of the pipe  504 . In some embodiments, the heated water  522  may be provided via a non-metallic pipe that couples the outlet of the microwave unit  508  to the inlet  524 . In some embodiments, the inlet  524  of the crude oil pipe  504  may be located such that the heated water  522  is directed at the oil and gas interphase of the crude oil feed stream. For example, in such embodiments, the inlet  524  to the crude oil pipe  504  may be located at a level of about 50% to about 60% from the top of the pipe  504 . 
     In some embodiments, the microwave unit  508  may provide microwaves having a frequency in the range of about 890 MHz to about 940 MHz or a frequency in the range of about 2400 MHz to about 2500 MHz. In some embodiments, the microwave unit  508  may provide microwaves at a frequency of about 915 MHz or about 2450 MHz. In other embodiments, the microwave unit  508  may provide microwaves at different frequencies. In some embodiments, the microwave unit  508  may be manufactured by Industrial Microwave Systems, LLC, of New Orleans, La., USA. In some embodiments, the microwave unit  508  may be coupled to the pipe  504  transporting the crude oil feed stream and positioned relatively close to the pressure vessel  510  so that the separated H 2 S and light end components may be more effectively removed from the vessel  508 . As previously noted, some embodiments may include the retrofit or modification of existing microwave systems to provide heating for crude oil stripping. 
     After heating by the microwave unit  508 , the heated crude oil stream may be provided to the pressure vessel  510  for separation. For example, separated gas  526  and separated crude oil  528  may exit the pressure vessel  510  and be provided to downstream facilities for further processing. Additionally, produced water  530  from the crude oil may exit the pressure vessel  510 . 
     The control system  502  includes a controller  532  and an analyzer  534 . The analyzer  534  may detect the properties of the separated crude oil  528  to determine parameters (for example, properties and composition) of the separated crude oil  528 . For example, in some embodiments, the analyzer  534  may analyze the separated crude oil  528  to determine the amount of H 2 S present in the separated crude oil  528 , the amount of light end components present in the crude oil  528 , and the Reid vapor pressure (RVP) of the separated crude oil  528 . The analyzer  534  may output a signal  536  indicative of the determined parameters of the separated crude oil  528  to the controller  532 . 
     The controller  532  receives the signal  536  and may determine whether the crude oil parameters deviate from a crude oil specification for the separated crude oil  528 . Based on the determination, the controller  532  may provide a control signal  538  to the microwave unit  508 . The control signal  538  may modify the power of microwaves used to irradiate the treated water  522  and, consequently, the temperature of the heated water  522  provided to the crude oil feed stream via the inlet  524 . In some embodiments, the controller  532  may compare the crude oil parameter to a stored value, such as a value obtained from the crude oil specification. In some embodiments, the comparison may determine whether the crude oil parameter deviates from the stored value by a threshold amount or threshold percentage. In some embodiments, the controller  532  may compare the crude oil parameter to a threshold value to determine whether crude oil parameter is less than or exceeds the threshold value. In some embodiments, the control system  502  may monitor and control the microwave unit  508  based on one parameter or multiple parameters. In other embodiments, the control system  502  may monitor and control the microwave unit  508  based on a parameter (for example, temperature of the heated water  522 ). 
     For example, in some embodiments, the amount of H 2 S in the separated crude oil  528  may be compared to a threshold value for stabilized crude oil that meets or exceeds a crude oil specification. If the controller  532  determines that the amount of H 2 S in the separated crude oil  528  exceeds the threshold value, the controller  532  may increase the power of the microwave unit  508  via the control signal  538 . To promote removal of H 2 S, for example, the controller  532  may increase the power of the microwave unit  508  to raise the temperature of the heated water  522 , thus providing more heating at the oil-gas interphase of the crude oil. 
     In some embodiments, the controller  532  may include a processor and memory to enable processing of crude oil parameters received from the analyzer. For example, the controller  532  may include one or more processors. In some embodiments, the controller  532  may include an application-specific integrated circuit (AISC). Additionally, in some embodiments the controller  532  may include a single-core processors and multicore processors. The controller  532  may further include a memory (which may include one or more tangible non-transitory computer readable storage mediums) such as volatile memory, such as random access memory (RAM), and non-volatile memory, such as ROM, flash memory, a hard drive, any other suitable optical, magnetic, or solid-state storage medium, or a combination thereof. The memory may store executable computer code having computer program instructions for implementing one or more techniques described in the disclosure, For example, the executable computer code may include instructions for processing parameters of crude oil and controlling a microwave unit in accordance with embodiments of the present disclosure. 
     In some embodiments, the control system  502  may include or implement aspects of the performance monitoring described in U.S. Pat. No. 9,092,124 entitled “System and method for effective plant performance monitoring in gas oil separation plant (GOSP)” and issued Jul. 28, 2015, a copy of which is incorporated by reference. 
       FIG. 6  depicts an operation unit  600  of a crude oil processing plant using microwave heating and a control system  602  in accordance with an example embodiment of the disclosure.  FIG. 6  also depicts a crude oil pipe  604 , a mixer  606 , a microwave unit  608 , and a pressure vessel  610 . 
     The crude oil pipe  604  may provide a crude oil stream to the mixer  606 . The mixer  606  may be used, in some embodiments, to promote mixing of the crude oil steam. In some embodiments, the mixer  606  may be eliminated and the operation  600  may not include the mixer  606 . 
     The microwave unit  608  (which may include a microwave source) may operate in a manner similar to the microwave source and separator illustrated supra and described in  FIG. 4 . For example, treated water  612  may be provided to the microwave unit  608  for heating by microwaves. The microwave unit  608  may output heated water  614  which may be provided to the crude oil feed stream via an inlet  616  of the pipe  604 . In some embodiments, the heated water  614  may be provided via a non-metallic pipe that couples the outlet of the microwave unit  608  to the inlet  616 . In some embodiments, the inlet  616  of the crude oil pipe  604  may be located such that the heated water  614  is directed at the oil and gas interphase of the crude oil feed stream. For example, in such embodiments, the inlet  616  to the crude oil pipe  604  may be located at a level of about 50% to about 60% from the top of the pipe  604 . In some embodiments, a first portion of the heated water  614  may be directed at the oil-gas interphase of the crude oil feed stream via the inlet  616 , and a second portion of the heated water  614  may be directed at the oil-water interphase of the crude oil feed stream via a second inlet. 
     In some embodiments, the microwave unit  608  may provide microwaves having a frequency in the range of about 890 MHz to about 940 MHz or a frequency in the range of about 2400 MHz to about 2500 MHz. In some embodiments, the microwave unit  608  may provide microwaves at a frequency of about 915 MHz or about 2450 MHz. In other embodiments, the microwave unit  608  may provide microwaves at different frequencies. In some embodiments, the microwave unit  608  may be manufactured by Industrial Microwave Systems, LLC, of New Orleans, La., USA. In some embodiments, the microwave unit  608  may be positioned relatively close to the pressure vessel  610  so that the separated H 2 S and light end components may be more effectively removed from the vessel  610 . 
     After heating by the microwave unit  608 , the heated crude oil stream may be provided to the pressure vessel  610  for gas and liquid separation. Separated gas  618  and separated crude oil  620  may exit the pressure vessel  610  and be provided to downstream facilities for further processing. As also shown in  FIG. 6 , produced water  622  from the crude oil may exit the pressure vessel  610 . 
     Some embodiments may include the retrofit or modification of existing microwave systems to provide heating for crude oil stripping. For example, in some embodiments a microwave water cut meter used to measure the water content in crude oil may be retrofitted or modified for use as the microwave unit  608  for heating for separation of H 2 S and light end components in the crude oil stripping operation  600 . 
     The control system  602  may operate in a manner similar to the control system  502  depicted in  FIG. 5  and discussed supra. For example, the control system  602  shown in  FIG. 6  includes a controller  624  and an analyzer  626 . The analyzer  626  may analyze the separated crude oil  620  to determine parameters (for example, properties and composition) of the stabilized crude  620 . For example, in some embodiments, the analyzer  626  may analyze the separated crude oil  620  to determine the amount of H 2 S present in the separated crude oil  620 , the amount of light end components present in the separated crude oil  620 , and the Reid vapor pressure (RVP) of the separated crude oil  620 . The analyzer  626  may output a signal  628  indicative of determined parameters of the separated crude oil  620  to the controller  624 . 
     The controller  624  receives the signal  628  and may determine whether the crude oil parameters deviate from a crude oil specification for the separated crude oil  620 . Based on the determination, the controller  624  may provide a control signal  630  to the microwave unit  608 . The control signal  630  may modify the amount of microwaves used to heat the treated water  612  and, consequently, the temperature of the heated water  614  provided to the crude oil feed stream via the inlet  616 . In some embodiments, the controller  624  may compare the crude oil parameter to a stored value, such as a value obtained from the crude oil specification. In some embodiments, the comparison may determine whether the crude oil parameter deviates from the stored value by a threshold amount or threshold percentage. In some embodiments, the controller  624  may compare the crude oil parameter to a threshold value to determine whether crude oil parameter is less than or exceeds the threshold value. In some embodiments, the control system  602  may monitor and control the microwave unit  608  based on one parameter or multiple parameters. In other embodiments, the control system  602  may monitor and control the microwave unit  608  based on a parameter (for example, temperature of the heated water  614 ). 
     For example, in some embodiments, the amount of H 2 S in the separated crude oil  620  may be compared to a threshold value for stabilized crude oil that meets or exceeds a crude oil specification. If the controller  624  determines that the amount of H 2 S in the separated crude oil  620  exceeds the threshold value, the controller  624  may modify the operation of the microwave unit  608  via the control signal  630 . To promote removal of H 2 S, for example, the controller  624  may increase the power of the microwave unit  608  to raise the temperature of the heated water  614 , thus providing more heating at the oil-gas interphase of the crude oil. 
     In another example, the amount of salt in the separated crude oil  620  may be compared to a threshold salt value for stabilized crude oil that meets or exceeds a crude oil specification. If the controller  624  determines that the amount of salt in the separated crude oil  620  exceeds the threshold value, the controller  624  may modify the operation of the microwave unit  608  via the control signal  630 . To promote removal of salt, for example, the controller  624  may increase the power of the microwave unit  608  to raise the temperature of the heated water  614  and provide more heating at the oil-water interphase of the crude oil. 
     In some embodiments, the controller  624  may include a processor and memory to enable processing of crude oil parameters received from the analyzer. For example, the controller  624  may include one or more processors. In some embodiments, the controller  624  may include an application-specific integrated circuit (AISC). Additionally, in some embodiments the controller  624  may include a single-core processors and multicore processors. The controller  624  may further include a memory (which may include one or more tangible non-transitory computer readable storage mediums) such as volatile memory, such as random access memory (RAM), and non-volatile memory, such as ROM, flash memory, a hard drive, any other suitable optical, magnetic, or solid-state storage medium, or a combination thereof. The memory may store executable computer code having computer program instructions for implementing one or more techniques described in the disclosure, For example, the executable computer code may include instructions for processing parameters of crude oil and controlling a microwave unit in accordance with embodiments of the present disclosure. 
     In some embodiments, the control system  602  may include or implement aspects of the performance monitoring described in U.S. Pat. No. 9,092,124 entitled “System and method for effective plant performance monitoring in gas oil separation plant (GOSP)” and issued Jul. 28, 2015, a copy of which is incorporated by reference. 
     In some embodiments, a microwave source may be placed upstream of one or more units of a gas oil separation plant (GOSP).  FIG. 7  depicts a gas oil separation process  700  of a gas oil separation plant and having one or more microwave units in accordance with an example embodiment of the disclosure. The gas oil separation process  700  includes a high pressure production trap (HPPT)  702 , a low pressure production trap (LPPT)  704 , a dehydrator  706 , a desalter  708 , a stabilization unit  710 , and a compression train  712 . 
     As shown in  FIG. 7 , a wet crude feed  714  may be provided to the HPPT  702  to separate oil, gas, and water in the wet crude feed  714 . Separated water  716  and separated oil  718  exits the HPPT  702 , and the separated gas  720  may be provided to the compression train  712  for gas processing. The crude oil output from the HPPT  702  is provided to the LPPT  704  for further separation of oil, gas, and water at a low pressure. Separated gas  722  exits the LPPT  704  and may be combined with the separated gas  720  from the HPPT  702  and provided to the compression train  712  for gas processing. The crude oil  724  output from the LPPT  702  is provided to the dehydrator  706  for removal of formation water from the crude oil. Separated water  726  exits the dehydrator  706 , and the crude oil  728  output from the dehydrator  706  is provided to the desalter  708 . 
     Wash water  730  may also be provided to the desalter  708  for removal of salt from the crude oil to meet or exceed salt content specifications for the crude oil. Separated water  732  exits the desalter  708 , and the crude oil  734  output from the desalter  708  is provided to the stabilization unit  710 . The crude stabilization unit  710  may also include or be referred to as a stripper unit and may separate H 2 S and light end components  736  from the crude oil to meet H 2 S and vapor pressure specifications for the crude oil. The stabilization unit  710  outputs stabilized crude  738  having, for example, salt content, H 2 S, and light end components within a desired crude oil specification. 
     In some embodiments, a microwave unit  740  may be placed upstream of the HPPT  702  (for example, at an entrance to the HPPT  702 ) to improve separation of oil, gas, and water in the crude oil in the HPPT  702 . As shown in  FIG. 7 , in some embodiments, a microwave unit  742  may be placed downstream of the HPPT  702  and upstream of the LPPT  704  (for example, at an entrance to the LPPT  704 ) to improve separation of oil, gas, and water in the crude oil in the LPPT  704 . In some embodiments, a microwave unit  744  may be placed downstream of the LPPT  704  and upstream of the dehydrator  706  (for example, at an entrance to the dehydrator  706 ) to improve dehydration of the crude oil. In some embodiments, a microwave unit  746  may be placed downstream of the dehydrator  706  and upstream of the desalter  708  (for example, at an entrance to the desalter  708 ) to improve desalting of the crude oil. In some embodiments, a microwave unit  748  may be placed downstream of the desalter  708  and upstream of the stabilization unit  710  (for example, at an entrance to the stabilization unit  710 ). For example, in such embodiments, the microwave unit  748  may promote the removal of H 2 S and light end components by heating at the oil-gas interphase of the crude oil before the crude oil is processed in the stabilization unit  710 . 
     In some embodiments, a gas oil separation plant having the units depicted in  FIG. 7  may have one of or any combination of the microwave units  740 ,  742 ,  744 ,  746 , and  748 . For example, in some embodiments, a gas oil separation plant may only have the microwave unit  742  for improving separation in the HPPT  702  and the microwave unit  724  for improving separation in the LPPT  704 . In another example, if effective oil, gas, and water separation is not achieved in the upstream units of a gas oil separation plant, the microwave unit  748  may be used to improve separation in the stabilization unit  710 . In some embodiments, any of the microwave units  740 ,  742 ,  744 ,  746 , and  748  may be implemented in the configuration  300  described supra and depicted in  FIG. 3 . In some embodiments, any of the microwave units  740 ,  742 ,  744 ,  746 , and  748  may be implemented in the configuration  400  described supra and depicted in  FIG. 4 . It should be appreciated that the implementation of the microwave units  740 ,  742 ,  744 ,  746 , and  748  in the configuration  400  described supra and depicted in  FIG. 4  may depend on the availability of treated water and the distance to a source of treated water. 
     In some embodiments, one or more of the microwave units  740 ,  742 ,  744 ,  746 , and  748  may each be controlled via control system similar to the control systems  502  and  602  discussed supra. For example, if the amount of salt in the stabilized crude oil  738  exceeds a threshold salt value, the microwave unit  746  may be controlled to increase the temperature of the crude oil provided to the desalter  708 . Similarly, other microwave units may be controlled via a control system in response to monitored crude oil parameters in the crude oil  738 . 
       FIG. 8  depicts a process  800  for processing crude oil using microwave heating in accordance with an example embodiment of the disclosure. Initially, water may be obtained from a crude oil stream (block  802 ). For example, as previously discussed, water from a water phase of a crude oil stream may be obtained as a side-stream from a pipe transporting crude oil. Solids may be separated from the water using a solids separator to produce filtered water (block  804 ). For example, a solids separator may remove particulate solids and other solid contaminants from the water obtained from the crude oil stream. 
     The filtered water may be irradiated with microwaves in a microwave to produce heated water (block  806 ). For example, the filtered water from the solids separator may be at a first temperature and the filtered water may be heated to a second temperature by irradiation with microwaves. The heated water from the microwave unit may be directed at a gas-oil interphase of the crude oil stream (block  808 ). For example, the heated water may be directed from an outlet of the microwave unit to an inlet at a crude oil pipe that directs the heated water to the gas-oil interphase of the crude oil stream. The crude oil stream may then be provided to a crude oil processing unit (such as a high pressure production trap (HPPT), low pressure production trap (LPPT), or stabilization unit) for processing (block  810 ). As discussed supra, the heating of the gas-oil interphase via the heated water may promote separation of components (for example, H 2 S and light end components) of crude oil stream in the crude processing unit. 
       FIG. 9  depicts a process  900  for processing crude oil using microwave heating in accordance with an example embodiment of the disclosure. Initially, treated water may be obtained from a water treatment unit (block  902 ), such as a water treatment unit if a crude oil processing plant (for example, a gas-oil separation plant). The treated water may be irradiated with microwaves in a microwave to produce heated water (block  904 ). For example, the treated water from may be at a first temperature and the treated water may be heated to a second temperature by irradiation with microwaves. A first portion of the heated water from the microwave unit may be directed at a gas-oil interphase of the crude oil stream (block  906 ). For example, the heated water may be directed from an outlet of the microwave unit to a first inlet at a crude oil pipe that directs the heated water to the gas-oil interphase of the crude oil stream in the pipe. 
     A second portion of the heated water from the microwave unit may be directed at an oil-water interphase of the crude oil stream (block  908 ). For example, the heated water may be directed from an outlet of the microwave unit to a second inlet at a crude oil pipe that directs the heated water to the oil-water interphase of the crude oil stream in the pipe. The crude oil stream may then be provided to a crude oil processing unit (such as a dehydrator or desalter) for processing (block  910 ). As previously discussed, the heating of the gas-oil interphase via the heated water may promote separation of components (for example, H 2 S and light end components) of crude oil stream. Additionally, the heating of the oil-water interphase via the heated water may promote separation of water and salt of the crude oil stream via, in some embodiments, gravity separation. 
     Ranges may be expressed in the disclosure as from about one particular value, to about another particular value, or both. When such a range is expressed, it is to be understood that another embodiment is from the one particular value, to the other particular value, or both, along with all combinations within said range. 
     Further modifications and alternative embodiments of various aspects of the disclosure will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the embodiments described in the disclosure. It is to be understood that the forms shown and described in the disclosure are to be taken as examples of embodiments. Elements and materials may be substituted for those illustrated and described in the disclosure, parts and processes may be reversed or omitted, and certain features may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description. Changes may be made in the elements described in the disclosure without departing from the spirit and scope of the disclosure as described in the following claims. Headings used described in the disclosure are for organizational purposes only and are not meant to be used to limit the scope of the description.