WO2006083251A1

WO2006083251A1 - Method for performing chemical reactions in a continuous segmented plug flow reactor

Info

Publication number: WO2006083251A1
Application number: PCT/US2005/003373
Authority: WO
Inventors: Donald E. Oulman; Randal J. Bernhardt
Original assignee: Stepan Company
Priority date: 2005-02-03
Filing date: 2005-02-03
Publication date: 2006-08-10

Abstract

A process for performing chemical reactions and producing chemical compounds in a continuous segmented reactor vessel (01) with internal heat transfer elements (50), which exhibits a reaction profile approximating a number of continuous stirred tank reactors in series, but which exhibits very high heat transfer, high reaction throughput, high reactant conversion rates, the ability to be used in a variety of different chemical reactions, and low operating costs.

Description

METHOD FOR PERFORMING CHEMICAL REACTIONS IN A CONTINUOUS SEGMENTED PLUG FLOW REACTOR

FIELD OF THE INVENTION [0001] The invention relates to a method for continuously reacting chemical compounds, more specifically, a method for reacting chemical compounds in a continuous segmented tubular or plug flow type reactor preferably containing multiple segmented reaction chambers and internal heat transfer.

BACKGROUND OF THE INVENTION [0002] Industrial scale production of most chemicals is limited by the reaction kinetics of the particular reaction and, significantly, the attendant reaction environment. Yield, rate of production, and reaction .efficiency will depend on a number of variables, including, for example, the concentrations of the reactant(s), product(s), and by-ρroduct(s); time; temperature; and pressure. Chemical reactor designs have evolved, therefore, in attempts to optimize industrial chemical production, and to pursue new products and uses, reduce fixed and operating costs, increase safety, minimize waste and emissions, and increase yield and efficiency. [0003 ] For example, one type of chemical reactor is a single batch reactor. Batch reactors can exhibit high reactant conversion ratios, but suffer from inefficiencies such as equipment downtime, lengthy product removal, cleaning, maintenance, and input of raw materials. Fig. 2 shows a reaction profile of a single batch reactor. Generally, batch reactors are preferred for small-scale production of high priced products such as multiple low volume products produced in the same equipment, or when continuous flow processing is difficult, as can be the case with highly viscous or sticky materials. Because product quality generally varies from batch to batch, a batch reactor is often unsuitable for many industrial applications. Batch reactors are also generally recognized in the chemical processing industry as involving greater operating costs and larger physical equipment requirements than continuous or tubular reactors.

[0004] A second type of chemical reactor is a continuous stirred tank reactor ("CSTR"). A CSTR typically exhibits higher throughput and lower overhead costs, but may suffer from low reactant conversion ratios. A CSTR often takes the form of a tank, usually associated with a mechanism for vigorous agitation into which the reactants and other ingredients are fed on a continuous basis. The resultant product is continuously withdrawn at the same rate that the reactants are added into the reactor. In this type of processing system, however, all of the reactants may not be completely consumed. Further, because the system is often turbulently agitated, fresh reactants introduced into the system may exit the reactor with the final product, rather than be incorporated into that final product. Such a production outcome is undesirable. [0005] A third type of reactor is a "plug flow" reactor. In a plug flow reactor, reactants are continuously introduced, and products continuously removed, similar to a CSTR. However, rather than randomly intermixing the reactants, as in a CSTR, a plug flow reactor may exhibit a substantially even concentration gradient with respect to residence time or distance in the reactor, after the reactants have been introduced. In an idealized plug flow reactor, the starting components are pushed through a tubular vessel, while reacting with each other as they travel, acting as a "plug" or "piston" that travels the length of the tube. Fig. 3 shows a reaction profile of an idealized plug flow reactor. A distinct advantage of such a plug flow reaction is that the reaction kinetics result in a fast, yet highly efficient, conversion of reactant to end product.

[0006] A conventional plug flow reaction comprises an extremely long, narrow tube. U.S. Patent No. 5,779,994 discloses some typical tubular plug flow reactors. The reactor residence times are dictated by the length and radius of the tube and the flow rate of the reactants disposed therein. However, such tubular plug flow reactors suffer from a number of disadvantages which make it difficult for industrial application in many cases. For example, the tube may need to be extremely long, often on the order of hundreds of meters long, to provide sufficient residence time to achieve a desired conversion for a given chemical reaction. Such a device could take up valuable space in a manufacturing facility resulting in a significant increase in overhead costs. Alternatively, if the tube is curved to optimize space, uniform heating, mid- process monitoring or regulating, and mixing become difficult. In any case, because the length of the tube is dictated by the requirements of a specific reaction, a long-tube reactor is incapable of performing as a "one-size-fits-all" reactor for numerous chemical reactions. Furthermore, it is difficult to adjust or fine tune temperature, residence time, or concentration gradients in any tubular reactor, and difficult to obtain uniform mixing of the reactants during reaction processing. U.S. Patent No. 5,409,672 discusses some of the deficiencies of conventional long-tube plug flow reactors.

[0007 ] Some other conventional reactors approximate plug flow characteristics by using either a number of cascading CSTR' s in series (see Kirk-Other, Encvcloυedia of Chemical Tech., vol. 20, p. 1008 (4th Ed. 1996)), or a segmented tubular reactor (see, e.g., U.S. Patent Nos. 4,737,349; 6,451,268; 6,673,243; 5,945,529; and 4,313,680). A reaction profile for either such arrangement is shown in Fig. 4, where each chamber of an idealized segmented tubular reactor acts like a single tank in a series of CSTR' s. As more CSTR' s are added in series, or more segments are added, the reactor begins to approximate plug flow. A distinct disadvantage with the use of CSTR' s in series, however, is the costly overhead of maintaining multiple CSTR' s, each of which may have separate heating and mixing systems, as well as the extra space requirements of multiple reactors. Additionally, multiple CSTR' s require numerous process and utility connections, which make installation complicated and costly.

[0008] Prior segmented tubular reactors also suffer from many drawbacks. Segmented tubular reactors are often difficult to construct. Conventional segmented tubular reactors may have partitions welded or bonded into place within an external shell, and are difficult to clean and maintain. Segmented tubular reactors which utilize a shorter length and wider radius are difficult to uniformly heat with heating jackets or external heating coils. Reactors with narrower radii generally remain extremely long, suffering from the same drawbacks as a normal tubular reactor. Additionally, in order to optimize reaction kinetics, each segment is usually mixed or stirred independently. However, it is difficult to fit mechanical mixing or stirring means in a tubular reactor, and if the moving parts for mechanical mixing break or clog, it is difficult to take apart the segmented reactor for maintenance or repair. Internal mechanical mixers/stirrers may also get in the way of the other internal components of the device, making internal heating difficult or impossible. Furthermore, conventional segmented tubular reactors do not provide a mechanism for mid-process removal of by-products, mid-process regulation or monitoring, or mid-process addition of additives, catalyst, or reactants. Conventional segmented reactors are also typically designed for, and may only be appropriate for, a single reaction. They are incapable, without significant and costly design modifications in size and/or shape, of processing a variety of chemical reactions.

[0009 ] Added to the foregoing shortcomings of conventional segmented tubular/plug flow reactors is that very little may be known as to which chemical reactions are suitable for such a reactor or what necessary processing variables might be required. Many reactions are simply incompatible with a segmented plug flow-type reactor, or otherwise commercially impracticable or undesirable for such a reactor. Conventional long-tube or segmented tubular/plug flow reactors must often be specifically constructed to satisfy the processing requirements of a given singular chemical reaction. Input flow rates, reactant concentrations, reaction times, temperatures, and pressures, as well as cost and productivity concerns, all vary depending on the desired chemical process.

[0010] For example, little or no development has been done utilizing a segmented plug flow type reactor for the production of TEA esteramine, biodiesel, betaines, C₁₈ fatty acid from methyl esters, phthalic acid polyol, methyl esters, hydrotropes, amides, and the like.

[0011] Therefore, there is presently a need for a segmented chemical reactor capable of approximating plug flow, with a highly efficient conversion of reactants to intermediary or final product; uniform internal heating; simple non-intrusive stirring/mixing; monitoring and regulating flexibility; easy construction and maintenance; and the ability to function as an installed modular unit that is capable of being utilized for numerous different reactions in a cost-effective and efficient manner.

BRIEF SUMMARY OF THE INVENTION [0012] One embodiment of the present technology is a reactor vessel for efficiently performing chemical reactions, characterized by high reactant to intermediary or final product conversion ratios, substantially continuous production, high throughput rates, and low operating, maintenance, and construction costs. The reactor is preferably suitable for multiple different chemical reactions and need not be custom-made for a particular reaction. Preferred embodiments of the reactor may include, for example, features which enable a reaction environment to be varied without changing the basic design of the reactor. Furthermore, preferred embodiments of the reactor are easily capable of simplified assembly, modification, repair, cleaning, and routine maintenance. [ 0013 ] The present technology preferably achieves efficient intermediary or final chemical product production by approximating a plug flow reaction profile and/or the reaction profile of a series of CSTR' s. The reactor can preferably exhibit very high heat transfer, turbulent flow within each section or segment, and flexibility for varying reaction parameters as desired. [ 0014 ] Embodiments of the reactor may comprise, for example, an outer reactor shell with a reactant inlet at one end and an intermediary or final product outlet at the opposite end, optional additional outlets for vapor and/or byproduct removal, and optional ports for monitoring, sampling, mixing, or varying the reaction. Within the reactor, a series of two or more segmented reaction chambers are defined by partitions, preferably alternating upper and lower partitions. The partitions can be configured such that a fluid flowing into the reactant inlet will flow in a path from one reaction chamber to the next, with turbulent flow within each reaction chamber, but minimal backflow from one chamber to a previous one. Preferably, lower partitions are in sealed communication with an inner wall of the reactor shell while upper partitions provide a space along the top for by-product vapor to travel to a vapor removal

outlet.

[0015] The reactor may further comprise one or more heat transfer elements, preferably fluid or steam filled tubes, which may extend into or through each reaction chamber. One particularly preferred embodiment utilizes U-shaped steam filled heating tubes which enter the reactor at the inlet end, travel through each reaction chamber, reverse direction, and traverse through the chambers again to the inlet end. Most preferably, the U-shaped tubes extend through each alternating partition. Although not wanting to be bound by any particular theory, it is believed that by having heat transfer elements which extend internally into and/or through each reaction chamber, substantially uniform and efficient heating or cooling of the reactants can be achieved. Moreover, it is also believed that the internal heat transfer elements promote desirable mixing and turbulent flow within each reaction chamber. [0016] One advantage of the preferred embodiments of the present technology is that the internal partitions may be built into a bundle of heat transfer elements, and this bundle may be configured for easy removability for cleaning, repair, or maintenance purposes. Additionally, construction of the reactor vessel is greatly simplified. Preferably, edges of the partitions requiring sealed communication with the inner wall of the reactor contain rubber or Teflon^® seals, gaskets, or other suitable type of sealing elastomer. Such partitions requiring sealed communication with the inner wall of the reactor may also be made from a metal, such as metal sheeting.

[0017] In order to reduce the number of necessary connections to the reactor, in some embodiments of the present technology, U-shaped heat transfer elements may flow into a heating media router head which distributes fresh heating media and removes circulated, used media. For example, a heating router head may comprise of a steam inlet which leads to U-tube inlets, and a condensate outlet which accepts condensate and/or steam which has completed a cycle within a particular heat transfer element.

[0018] Furthermore, preferred embodiments of the present technology comprise one or more non-mechanical fluid mixers contained in each of the reaction chambers. The non-mechanical fluid mixers are preferably gas inlets/sparges and/or any other means for mixing a fluid which does not involve moving spinners, propellers, blades, and the like. Again, not wanting to be bound by any particular theory, it is believed that mixing the reactants within each reaction chamber may generally enhance the reaction rate and overall reaction kinetics.

[0019 ] Additional embodiments may also include one or more ports or inlets for intermediary or final product sampling or for the addition of further reaction materials (i.e., additives, catalysts, buffers, or additional amounts of starting reactants). For example, some preferred embodiments of the reactor include a series of one or more ports in each reaction chamber. These ports may be multi-functional. The ports are preferably capable of accepting an additive, catalyst, buffer, or additional reactant. The ports may also comprise monitoring devices such as thermocouples, thermometers, flow meters, pH analyzers, viscosity analyzers, pressures gauges or the like.

[ 0020] In the most preferred embodiments, where possible, ports and inlets are consolidated to reduce the number of necessary external connections to the reactor. For example, gas sparges may be connected to a single gas input line, a U-tube heat transfer head may be utilized, and/or any other means may be used to minimize connections. Preferably, the reactor is capable of being utilized as a modular or "drop-in" reactor which may be easily shipped, assembled, and incorporated into a variety of established chemical production processes within a chemical production facility.

[0021] It is also preferred that the presently described reactor be capable of performing two or more different types of chemical reactions, overcoming the general limitation of prior reaction-specific tubular reactors or segmented reactors. Preferably, only residence times, temperatures, flow rates, and/or pressure need be varied to accommodate a particular reaction. Some embodiments may also provide for variable mid-process product or reactant removal, or alternatively, addition of reactant materials, additives, buffers, etc.

BRIEF DESCRIPTION OF THE DRAWINGS [0022 ] Fig. 1 is a cross-sectional view showing an internal construction of a segmented reactor in accordance with at least one embodiment of the

present invention.

[0023 ] Fig. 2 is a graph of a hypothetical single batch reaction profile, showing reactant concentration as a function of reaction time. [0024] Fig. 3 is a graph of a hypothetical tubular or plug flow reaction profile, showing reaction concentration as a function of distance along the length of the reactor.

[0025] Fig. 4 is a graph of a hypothetical segmented tubular or plug flow reaction profile with three segments, showing concentration as a function of distance along the length of the reactor.

[ 0026] Fig. 5 is an angled cut-away view showing an internal construction of a segmented reactor in accordance with at least one embodiment of the present technology. [0027] Fig. 6 A is a side view of the exterior of a segmented reactor with removable heat transfer element bundles and partitions, in accordance with at least one embodiment of the present technology.

[0028 ] Fig. 6B is a stand-alone side view of a removable U-shaped heat transfer element bundle and secured alternating partitions, in accordance with at least one embodiment of the present technology.

[ 0029 ] Fig. 6C is an end view of one upper partition in a segmented reactor, showing the cross sections of multiple heat transfer elements passing through the partition.

[0030] Fig. 6D is an end view of one lower partition in a segmented reactor, showing the cross sections of multiple heat transfer elements passing through the partition.

[0031] Fig. 7 is a side view of two removable heat transfer bundles, showing secured alternating partitions and heat transfer router heads, for insertion into both ends of a reactor. [0032] . Fig. 8 is a side view of a removable continuous heat transfer bundle, showing secured alternating partitions and opposing heat transfer router

heads.

[0033] Fig. 9 is a side view of the exterior of a segmented reactor, with by-product removal outlets and a series of multi-purpose ports.

[ 0034 ] Fig. 10 is a side view of the exterior of a segmented reactor, with by-product removal outlets and a series of multi-purpose ports.

[ 0035 ] Fig. HA is a side view of a heating medium router cap for a segmented reactor with multiple U-shaped heating tubes, according to at least one embodiment of the present technology.

[ 0036] Fig. HB is an end view of a heating medium router cap for a segmented reactor with multiple U-shaped heating tubes, according to at least one embodiment of the present technology.

[ 0037] Fig. IIC is a side view of a heating medium router cap, illustrating the relationship between the heating medium router cap and the U- shaped heating tubes.

[0038] Fig. HD is an end view of a heating medium router cap, illustrating the relationship between the heating medium router cap and the U- shaped heating tubes.

DETAILED DESCRIPTION OF THE INVENTION

[0039] The present technology provides a superior reactor vessel for performing a variety of chemical reactions. The reactor is preferably suited for pilot plant, laboratory, and/or industrial scale processing of chemical compounds. The reactor preferably exhibits a reaction profile approximating plug flow or a series of continuous stirred tank reactors. [0040 ] In one embodiment of the present technology, a continuous segmented chemical reactor is provided. The reactor may be a single modular unit, but preferably comprises separable or removable components. One preferred advantage of some embodiments of the technology is that the reactor requires relatively few external connections, which is desirable in a modern industrial plant. The reactor is preferably modular and capable of easy storage, maintenance, repair, transport, and installation, and is preferably easily configured and adjusted to pre-determined parameters for a given chemical reaction. Apparatus Exterior:

[0041] Fig. 1 shows one embodiment of the reactor 01 of the present technology. The reactor 01 preferably comprises a reactor shell 10, which may be cylindrical, rectangular, or any other suitable shape. Preferably, the reactor shell 10 is elongated in one dimension, most preferably in a length/width ratio of greater than about 3:1, more preferably, greater than about 5:1. The reactor shell 10 may be of any dimensions suitable for desired intermediary or final product volume output and/or desired reaction residence times. Preferably, the reactor shell 10 is between about 0.2 meters to about 1.0 meter in length for laboratory use, and between about 1.0 meter to about 50 meters in length for industrial use. Most preferably, the reactor shell 10 is between about 2.0 meters to about 10.0 meters in length, and between about 0.10 meters to about 3.0 meters in diameter.

[0042 ] The reactor shell 10 may be made of any material suitable for desired volume, pressure, temperature, and reaction conditions. The reactor shell 10 may also be made of a corrosion resistant or non-reactive material capable of withstanding desired temperatures, pressures, and/or other reaction conditions. Some preferred materials include stainless steel, titanium, glass, ceramic, coated metal, or composites. The reactor may alternatively be made of any suitable material and lined with a corrosion resistant, non-reactive material, such as glass or ceramic. In some instances it may not be necessary that the reactor be built of a non-corrosive material, and accordingly, it may also be constructed of materials such as copper, brass, iron, carbon steel, aluminum, and the like.

[ 0043 ] The reactor is preferably capable of withstanding temperatures of less than about minus 100 degrees Celsius, and temperatures of greater than about 400 degrees Celsius. It is also preferable that the reactor is capable of withstanding internal pressures of greater than about 250 psig, or maintaining a vacuum of less than about 0.1 psia. [0044] The reactor 01 preferably has a first (input) end 12 and a second (output) end 11. An inlet 20 is provided approximate to the first end 12, and an outlet 21 approximate to the second end 11. The inlet and outlets may be in any form of valve, stop-cock, connection port, or other opening or fluid regulator. Most preferably, the inlet 20 and outlet 21 are tubes extending from the reactor shell 10, which are capable of connection to valves, pumps, flow gauges, or pressure gauges, and which are capable of connection to an input flow of fluid, or a fluid output accepting tank. The inlet 20 is suitable for accepting one or more input compounds, and the outlet 21 is suitable for dispensing one or more final end products. The input materials may be reactants, catalysts, buffers, diluents, emulsifiers, or any other desirable materials. The term "fluid" is defined to mean any substance capable of flowing, including, but not limited to a liquid, gas, vapor, solid suspended in liquid or gas, liquid suspended in gas, solution, emulsion, or slurry.

[0045] One or more embodiments of the present technology may also include two or more inlets 20 for introduction of separate chemical compounds. For example, separate inlets 20 may be utilized for the introduction of separate chemical reactants, catalysts, and the like, or the reactants and/or other materials may be combined just prior to insertion into the reactor 01. The one or more inlets 20 and one or more outlets 21 may be equipped with automatic or manual valves, flow gauges, pressure gauges, or the like, and may be connected to any suitable pumps, containers, reactant sources, additional reactors, etc. Apparatus Interior:

[0046] The interior of the reactor 01 comprises two or more partitions

31 and 32, which define two or more reaction chambers 30. Preferably, the partitions 31 and 32 are alternating partitions, such that a fluid must pass over/around one and under/around the next partition, or vice-versa, in a general winding, alternating, serpentine, or repeating path. By "alternating partitions" is meant any pattern of upper/lower partitions, inner/outer partitions, left/right partitions, or the like. This definition may encompass one or more additional interstitial partitions without departing from the alternating pattern and the spirit and scope of the invention. The partitions 31 and 32 also preferably result in a sectional flow path for a fluid traveling from the input 12 to the output 11, meaning that the fluid flows from one chamber to the next, with little or no back-flow. [0047] The partitions 31 and 32 preferably define alternating gaps between the inner surface of the reactor shell 10 and any individual partition. The gaps may be of any width to allow desirable fluid volume rate, but are preferably between about 5 mm to about 5 meters. More preferably, the gap is between about 2 cm to about 100 cm, and most preferably, between about 5 cm and about 50 cm. [0048 ] The partitions 31 and 32 may be removable or non-removable.

In preferred embodiments, however, the partitions 31 and 32 are part of a unitary, removable inner unit, as shown in Fig. 6B. The partitions may be built into a unit or bundle comprising one or more heat transfer elements 50 which may be removed from the reactor shell 10 for cleaning, maintenance, or repair. "Heat transfer" is defined herein to mean heating, cooling, or temperature circulation by conduction, convention, or radiation.

[ 0049 ] The edges of each partition 31 or partition 32 which may contact with the inner surface of the reactor shell 10 preferably comprise seals or gaskets 33 which prevent fluid from passing through, as shown in Fig. 5. These seals or gaskets 33 may be made of any suitable material which substantially reduces fluid flow at the contact point between the partition edge and the inner wall of the reactor shell 10. Preferably, the seals or gaskets 33 are made of an elastomer such as Teflon^®, or plastic, or metal sheeting.

[0050] In some preferred embodiments of the present technology, a section of the upper partition(s) 31 do not contact the inner surface of the reactor shell 10. Instead, a vapor gap 35 may be provided along the top of the reactor, between the upper partitions 31 and the reactor shell 10 inner surface, as shown in Fig. 1. This gap is sufficient to allow vapor to pass along the top of the interior of the reactor 01. In this embodiment, therefore, the reactor is not entirely filled with fluid, but rather, fluid is inputted and removed such that a fluid level is preferably maintained at a level under the vapor gap 35 (as shown in Fig. 1). The reactor 01 may also comprise one or more fluid level indicators 24 for regulating fluid level.

[0051] In those embodiments utilizing a vapor gap 35, there is also provided a vapor by-product removal outlet 23. This outlet may be of any type sufficient to remove a vapor from the reactor 01, such as a simple outlet, valve, suction pump, gas pump, or the like. Preferably, this vapor by-product removal outlet 23 is located approximate to the first (input) end 12 of the reactor 01, such that a vapor current flows opposite the direction of reactant/intermediary or final product fluid flow. Although not intending to be bound by any theory, it is believed that this vapor cross current prevents contamination of downstream intermediary or end product with by-products from upstream, which is a further advantage of the presently described reactor technology.

Heat Transfer Elements:

[0052 ] The reactor may also comprise one or more internal heat transfer elements 50. "Heat transfer" is herein defined to mean heating, cooling, or temperature circulation by convention, conduction, or radiation. These heat transfer elements 50 may be of any type or form suitable for heating or cooling a fluid, such as heat transfer media filled tubes, electrical elements, refrigeration elements, or the like. The reactor may also be heated by additional external heating means such as heating jackets, heating baths, microwave energy, or the like. Alternatively, the reactor may be cooled by external cooling means such as refrigeration jackets, coolant baths, or the like. Again, not intending to be bound by any theory, it is believed, however, that internal heat transfer elements 50 promote very high heat transfer and additionally aid in turbulent flow within each internal reaction chamber 30. It is believed that fluid flowing from one chamber to the next, in addition to passing over or under a partition, must also pass around the heat transfer elements 50, thus promoting turbulent flow and uniform mixing.

[0053 ] Preferably, the internal heat transfer elements 50 are fluid filled heat-exchange tubes (i.e., heat exchange tubes which transfer heat from within the tube to the surrounding fluid, or vice-versa (i.e., heating or cooling the surrounding fluid). These tubular transfer elements 50 may enter the reactor 01 from one or both ends, exit the reactor at the same or opposite end, or enter and exit the reactor from its sides, as shown in Figs. 7-8. Preferably, the tubes are U-shaped tubes which enter the reactor at one end, pass through the length of the reactor, curve around, and exit at the same end, as shown in Fig. 1. The U- shaped heat transfer elements 50 may alternatively enter the reactor at both ends and continue part of the way through the reactor, as shown in Fig. 7, or enter the reactor at one end and exit the opposite end, as shown in Fig. 8. Most preferably, each heating tube passes through each internal reaction chamber 30, and through each partition 31 and 32. [0054] The heat transfer elements 50 are also preferably a bundle secured to, attached to, or passing through the alternating partitions 31 and 32, as shown in Fig. 6. "Secured to" is herein defined as meaning that the partitions may be removed from the apparatus as one piece, i.e., the partitions remain in relative position to each other when removed. The partitions may be adhered or press fit into place, or merely secured by virtue of heat transfer elements passing through them. The bundle of heat transfer elements 50 and alternating partitions 31 and 32 are preferably adapted to be removable. It is believed that a removable bundle or unit of heat transfer tubes 50 and partitions 31 and 32 enables simple assembly of the reactor 01, easy maintenance and cleaning of internal components, and simple repair. [0055 ] A bundle of heat transfer elements 50 and partitions 31 and 32 may be removable/insertable through one or both ends of a reactor 01. For example, as shown in Fig. 6, the bundle or unit may be a bundle of heat transfer elements 50, 51, 52, and so on, inserted at one end of the reactor shell 10, and extending the length of the reactor. Alternatively, as shown in Fig. 7, the bundle or unit may extend part of the way through the reactor shell 10, and one or more bundles may be inserted at both ends of reaction 01. A third alternative, shown in Fig. 8, involves the tubes 50 passing entirely through the reactor shell 10 from one end to the other end of reaction 01. Thus, it should be understood by those skilled in the art that a variety of configurations are contemplated, which are within the spirit and scope of the described present technology and claims.

[0056] The heat transfer elements 50 are preferably made of a thermally-conductive material appropriate for containing a cooled or heated fluid or gas. Suitable materials include, but are not limited to stainless steel, steel, cast or wrought iron, aluminum, copper, brass, titanium, coated metal, glass, ceramic, or plastic. Preferably, the heat transfer elements 50 are tubes are made of a metal with good thermal conductivity. By thermal conductivity is meant the ability of a material to transfer, rather than absorb, heat, and thus efficiently heat or cool a surrounding fluid. [0057 ] The heat transfer elements 50 are preferably straight, cylindrical tubes that are parallel to the longitudinal axis of the reactor shell 10. However, the heat transfer elements may also be curved, spiral, rectangular, or any other shape or direction or form capable of acting as a heat transfer element. The terms "tubes" and "tubular", in the claims and specification, are defined to mean any hollow, elongated shape, including, but not limited to shapes with circular, elliptical, square, rectangular, octagonal or other shaped cross-sections. The tubes may be of any suitable diameter and thickness to operate as heat transfer elements. Preferably, the tubes are between about 5 mm to about 50 cm in diameter, more preferably, between about 2 cm to about 20 cm in diameter, and most preferably, between about 5 cm to about 15 cm. The heat transfer element tube thickness may be between about 0.1 mm to about 30 mm, more preferably, between 2 mm to about 20 mm, and most preferably, between 1 mm to about 2 mm. f [ 0058 ] The heat transfer elements 50 may be filled with any suitable fluid, including, but not limited to water, steam, oil, refrigerant, liquid nitrogen, liquid oxygen, saline solution, or any other gas or liquid that results in a sufficient overall heat transfer coefficient. [ 0059 ] In preferred embodiments that utilize heat transfer elements 50 in the form of tubes, a suitable heat exchange router, supplier, pump, or the like may be used to supply heat transfer media to the tubes. For example, a heat transfer router 90 may be used, as shown in Figs. 1 IA-I ID. An example of a suitable heat transfer router may include a head, as shown in Fig. 1 IA-I IB, which attaches to an end of the reactor shell 10. The head 90 preferably has a heat transfer fluid input 91 and a heat transfer fluid output 92. It may further be internally divided into two zones: a fluid input zone 93 which routes input fluid to the input ends 51 of heat transfer elements 50, and a fluid output zone 94, which accepts fluid flowing out of the output ends 52 of the heat transfer tubes 50. The fluid input zone 93 and fluid output zone 94 are preferably divided unequally, as shown in Figs. HA and HB, to account for a vapor gap 35. In those embodiments that utilize a vapor gap 35, the horizontal midpoint of the bundle of heat transfer tubes will be closer to the bottom of the reactor shell 10, than the top. Mixing/Agitation: [0060] In order to achieve a reaction profile similar to a series of

CSTR' s, or to approximate plug flow, it is preferable that the reactor 01 exhibit turbulent flow or mixing within each internal reaction chamber 30. Although not wanting to be bound by any particular theory, it is believed that in some embodiments of the present technology, internal heat transfer elements 50 alone (through a "Pachinko effect") or by-product gas production may provide sufficient agitation within each internal reaction chamber 30. However, some embodiments of the present technology may also utilize one or more mixers 40 to further agitate the reactants. [0061] Preferably, the mixer 40 is non-mechanical, i.e., the mixer does not have moving parts such as mixing blades, propellers, stirrers, or the like. Non-mechanical mixers are preferred, as they can easily be accommodated within or into the reactor shell 10, along with the heat transfer elements 50. Furthermore, in those embodiments where the heat transfer elements 50 and partitions 31 and 32 are a removable bundle (e.g., Fig. 6), mixers 40 (preferably non-mechanical) can be designed so that they do not interfere with removing the bundle, or are first easily removable themselves.

[0062] It should be understood by those skilled in the art that some embodiments of the present technology may utilize only one mixer 40, or a series of mixers 40 along the length of the reactor 01. Preferably, one or more mixers 40 is provided for each internal reaction chamber 30, as shown in Fig. 1. The mixers 40 may be connected to the reactor 01 individually, or may be themselves connected in series or in parallel configuration. The mixers 40 may also be of constant or adjustable power, and may be individually adjusted accordingly. For example, it is believed that internal reaction chambers 30 nearer the first end 12 of the reactor 01 {i.e., "upstream") may have a higher production of by-product gas that may sufficiently agitate those particular chambers, while chambers 30 nearer the second end 11 of the reactor 01 {i.e., "downstream") may have less gas by-product production. Accordingly, the reactor 01 may be equipped with more vigorous mixers 40 for downstream chambers 30 than compared to upstream chambers 30, or may provide mixers 40 only into downstream chambers 30.

[ 0063 ] The mixers 40 are also preferably automatically or manually adjustable. It is envisioned that the mixers 40 may be set to different levels for different chemical reactions, or different viscosities or specific gravities of materials.

[0064] One example of a preferred mixer 40 is a gas input. A gas input may jet, bubble, or sparge a gas into a reaction chamber 30 to agitate a fluid within that chamber. Preferably, the mixer 40 (e.g., as a gas input) is perforated to promote bubbling and extends from the exterior of the reactor shell 10, into or flush with a reaction chamber 30. From the exterior of the reactor shell 10, mixer 40 may be connected directly to a gas source, or connected first in parallel or series with other gas inputs and then to a gas source. Suitable gases for use with the present technology may be any inert or non-reactive gas, including, but not limited to nitrogen, argon, helium, or the like. Alternatively, a reactive gas such as oxygen, hydrogen, methane, ethane, propane, butane, ammonia, carbon dioxide, or the like may also be utilized in certain reactions where a gas is a desirable reactant. Preferably, the mixing intensity of the mixers 40 may be adjusted by varying the flow rate or pressure of the gas. Preferred embodiments may also utilize gas input pressure or flow measurement gauges or monitoring devices without departing from the spirit and scope of the invention.

Apparatus By-Product Removal: [0065] In some reactions, it is desirable that by-products be removed during the reaction, as the presence of by-products may impede reaction kinetics. Some embodiments of the presently described technology may therefore also utilize one or more outlets for the removal of reaction byproducts. One type of preferred by-product removal outlet is a vapor removal outlet 23 on the top of the reactor shell 10. For example, in those embodiments which utilize a vapor gap 35, a vapor removal outlet 23 may be provided to remove by-product gases or other vapors from the reactor 01. Preferably, vapor removal outlet 23 is positioned approximate to the first end 12 of the reactor shell 10, so that the vapor by-products flow in a counter-current manner away from the chambers 30 containing lower concentrations of reactants and higher concentrations of product. The vapor removal outlet 23 may be a simple outlet, or may be connected to a vacuum or suction to promote vapor removal. If the reactor 10 itself is maintained under pressure, the pressure differential may also promote vapor removal. The vapor outlet 23 may lead to any form of device for vapor or gas storage, disposal, or removal. [ 0066] A second type of by-product removal may be heavy by-product removal, in the form of by-product solids or liquids. For example, one or more heavy by-product removal outlets 60 may be provided, as shown in Figs. 9 and 10. Heavy by-product outlets 60 are preferably equipped with manual or automatic gravity separation valves, interface valves, sight-glasses, or other apparatuses well known to those of ordinary skill in the art as being capable of removing a liquid or solid by-product without significant removal of the reactant or intermediary and/or final product. These outlets are preferably positioned on the bottom of the reactor shell 10 {See Figs. 9, 10). Additional Apparatus Components:

[0067 ] Some embodiments of the reactor 01 may also contain additional ports, inlets, outlets, or measurement devices. Preferably, the reactor 01 comprises one or more multi-purpose ports 70 in the reactor shell 10, which may introduce a variety of regulating or monitoring components into the reactor shell 10. For example, a multi-purpose port 70 may be configured to accept additional material input including, but not limited to a catalyst, an additive, a reactant, and a buffer. Alternatively, the multi-purpose port 70 may be configured to accept a sampling device for removing an amount of reactant/product mixture from a given reaction chamber 30. The multi-purpose port 70 may also be configured to accept one or more measurement devices such as thermocouples, thermometers, pressure gauges, pH analyzers, flow gauges, and viscosity gauges. In some embodiments of the present technology, the multipurpose port 70 may also be used to accommodate mixers 40 (preferably non-mechanical). In this manner, a single reactor 01 may accommodate a variety of different reaction variables or monitoring requirements without significant structural or design changes.

[0068] Preferably, the reactor comprises a series of multi-purpose ports

70. Each internal reaction chamber 30 may contain one multi-purpose port 70, as shown in Fig. 9, or each internal reaction chamber 30 may contain two or more multi-purpose ports 70 and 71, as shown in Fig. 10. These multi-purpose ports may be in addition to any number of by-product removal ports 60. In some embodiments, one set of multi-purpose ports 70 may be used for gas inputs, while a second set of multi-purpose ports 71 may be used for monitoring or further material addition. A series of multi-purpose ports 70 or 71 need not be uniform, and some ports may be used to monitor temperature, some for materials sampling, and some for materials addition, as desired for a given reaction.

Methods for Using the Apparatus:

[ 0069 ] The presently described technology also contemplates methods of performing chemical reactions in the described reactor. The reactor 01 is preferably capable of performing a broad variety of different types of chemical reactions without substantial modification to its size, shape, volume, or overall design. Preferably, reaction variables such as overall reaction time, residence time of reactants in each chamber 30, temperature, pressure, additive or catalyst inputted, and uniformity or mixing may be adjusted. For example, input rate of reactants or output rate of an intermediary or final product may be adjusted, the temperature of the heating elements may be adjusted, non-mechanical mixers may or may not be utilized, or be used at varying mixing capacities, and additives or catalysts may be inputted into one or more multi-purpose ports 70

or 71. [ 0070] The reactor described herein preferably may be utilized for any reaction in which matter needs to be removed, either by volatilization or gravity separation. Some reactions which may be performed in the present reactor include, but are not limited to esterification (methyl ester formation, triethanolamine ester formation), interesterification, transesterification (biodiesel, soy methyl ester, fatty methyl esters from triglycerides and methanol), hydrolysis (fatty acid from methyl esters, fatty acids from triglycerides, and other forms of fat splitting), alkoxylation (ethoxylation), polyesterification (phthalic anhydride or dimethyl phthalate and diethylene glycol), polyamidation (phthalic anhydride and diaminoethylene) oxidization (amineoxide formation), halogenation (formation of a dihalide), nitration, sulfonation (formation of a sulfonic acid or a sulfuric acid ester), amidation (ammonalysis, formation of monoethanolamides from organic acids or methyl esters or triglycerides, formation of diethanolamides from organic acids or methyl esters or triglycerides, and dimethlyamides of organic acids), saponification (of triglycerides or esters), dehydrogenation (formation of unsaturated organic chains), dehydration (formation of unsaturated organic chains), dehydrohalogenation, hydrogenalysis (formation of alcohols from esters or acids), ozonation, etherification (formation of ethers by the elimination of H₂O), quaternization (MeCl quaternization of an amine), imidazoline formation and the like. [0071] Preferably, one or more chemical reactants and any optional additives, catalysts, or buffers are inputted approximate to the first end 12 of the reactor 01, into one or more inputs 20, and form a mixture in a first internal reaction chamber 30. As more reactants are inputted, the previously inputted reactants preferably flow over or around a first partition 31 or 32, and into a second internal reaction chamber 30, over or around the next partition 31 or 32 and into the next internal reaction chamber 30 and so forth. Preferably, the partitions are alternating lower partitions 32 and upper partitions 31, although they need not be. Preferably, the flow within each internal reaction chamber 30 is turbulent, so that reactants which flow over or under a partition 31 or 32 are substantially uniformly and immediately mixed with the other reactants in the chamber. This turbulent flow may be induced by internal barriers, the internal heat transfer elements 50, or by mixers 40 which are preferably non- mechanical. [0072] The flow from the first end 12 to the second end 11 of reactor 01 preferably approximates a number of CSTR' s in series, or approximates plug _r flow. Preferably, reactants flow significantly from upstream reaction chambers 30 (i.e., approximate to the first end 12) to downstream reaction chambers 30 (i.e., approximate to the second end 11), with minimal backflow. The concentration of product in any downstream reaction chamber 30 is preferably greater than the concentration in any upstream reaction chamber 30, and the concentration of reactant in any downstream reaction chamber 30 is preferably less than the concentration in any upstream reaction chamber 30. Additional reactant, however, may be added at any downstream reaction chamber 30 as desired. [0073 ] Optionally, the heat transfer elements 50 may maintain a substantially uniform fluid temperature within each internal reaction chamber 30. The temperature may be the same in each internal reaction chamber 30, or may be different from chamber to chamber, however. For example, the temperature in each chamber may be uniform to within about 10 degrees Celsius, more preferably, to within about 5 degrees Celsius, and most preferably, to within about 3 degrees Celsius (depending upon the specific reactions desired). [ 0074 ] The temperature of a fluid within each reaction chamber 30 may be varied according to the desired parameters for a given chemical reaction. Preferably, the temperature of the fluid is between about minus 100 degrees Celsius to about 400 degrees Celsius. More preferably, the temperature is between about 50 degrees Celsius to about 200 degrees Celsius, or between about 100 degrees Celsius to about 200 degrees Celsius (depending upon the specific reaction(s) desired). Furthermore, the reactants may optionally be maintained under pressure or vacuum. The interior of the reactor shell 10 is preferably maintained at between about 0.1 psia to about 600 psig, more preferably between about 14.7 psia to about 100 psig. Given the nature of the reaction, however, and the design of the equipment, the reactor 01 may also be capable of pressures up to about 4000 psig.

[0075] A further variable that may be adjusted for different chemical reactions is residence time of a fluid stream within the reactor 01. By overall residence time is meant the average time that it would take a single particle to flow with the reactant/product mixture from the input 20 to output 21 of the reactor 01. Chamber residence time means the average time a single particle flowing with the mixture would spend within an individual reaction chamber. Preferably, either overall residence time or chamber residence time may be adjusted. Overall residence time is preferably adjusted by varying input and/or output flow rate. It is contemplated that some chemical reactions may require longer overall or chamber 30 residence times, while other reactions do not. Preferably, the overall residence time is between about 1 minute to about 30 hours. More preferably, the overall residence time is between about 5 minutes to about 16 hours (subject to the specific reaction desired). Most preferably, the residence times are between about 10 minutes to about 4 hours (subject to the specific reaction(s) desired).

[0076] The invention has now been described in such full, clear, concise and exact terms as to enable any person skilled in the art to which it pertains, to practice the same. It is to be understood that the foregoing describes preferred embodiments and examples of the invention and that modifications may be made therein without departing from the spirit or scope of the invention as set forth in the claims.

Claims

What is Claimed:

Claim 1 : A method for performing a chemical reaction comprising:

(a) substantially continuously inputting one or more chemical reactants into a first end of a reactor such that the one or more chemical reactants proceed from the first end of the reactor to a second end of the reactor, sequentially through two or more internal reaction chambers defined by two or more partitions;

(b) reacting or splitting the one or more chemical reactants in the internal reaction chambers such that the concentration of one or more products in a downstream chamber is greater than the concentration of one or more products in an upstream chamber;

(c) inducing turbulent flow within the internal reaction chambers;

(d) heating or cooling the internal reaction chambers with at least one heating or cooling element extending therein; and

(e) removing an intermediary or a final product from a product outlet proximate to the second end of the reactor.

Claim 2: The apparatus of claim 1, wherein the reactor is substantially horizontally oriented, and the partitions therein are substantially vertically oriented. Claim 3: The method of claim 2, wherein the two or more partitions are at least one upper partition and at least one lower partition in an alternating relationship.

Claim 4: The method of claim 1, wherein each of the internal reaction chambers is heated or cooled by at least one heat transfer element.

Claim 5: The method of claim 4, wherein each of the internal reaction chambers is heated by at least one of the heat transfer elements, each extending through each of the two or more partitions.

Claim 6: The method of claim 1, wherein the temperature of a fluid within an individual internal reaction chamber is maintained uniformly to within about 5 degrees Celsius.

Claim 7: The method of claim 1, wherein the turbulent flow is induced by imparting fluid flow around each of the heat transfer elements.

Claim 8: The method of claim 1, wherein the turbulent flow is induced by one or more non-mechanical mixers.

Claim 9: The method of claim 8, wherein the non-mechanical mixer bubbles, streams, or jets an inert gas into each of the internal reaction chambers. Claim 10: The method of claim 1, wherein the chemical reaction is selected from the group consisting of esterification, interesterification, transesterification, hydrolysis, alkoxylation, polyesterification, polyamidation, oxidization, halogenation, nitration, sulfonation, amidation, saponification, dehydrogenation, dehydration, dehydrohalogenation, hydrogenalysis, ozonation, etherification, quaternization, and imidazoline formation.

Claim 11: The method of claim 1, wherein the intermediary or the final product is selected from the group consisting of methyl ester, triethanolamine ester, biodiesel, soy methyl ester, fatty methyl esters from triglycerides and methanol, fatty acid from methyl esters, fatty acids from triglycerides, phthalic anhydride or dimethyl phthalate and diethylene glycol, amineoxide, dihalide, sulfonic acid, sulfuric acid ester, monoethanolamide, diethanolamides, dimethlyamides of i organic acids, alcohols, ethers, quaternized ammonium compounds, and imidazoline.

Claim 12: The method of claim 1, wherein the one or more chemical reactants are heated to a temperature between about 20 degrees Celsius to about 400 degrees Celsius.

Claim 13: The method of claim 12, wherein the one or more chemical reactants are heated to a temperature between about 50 degrees Celsius to about 150 degrees Celsius. Claim 14: The method of claim 1, wherein the interior of the reactor is maintained at a pressure of greater than about 100 psia..

Claim 15: The method of claim 1, further comprising the step of removing vapor from an outlet proximate to the first end of the reactor.

Claim 16: The method of claim 1, further comprising monitoring one or more of the following properties of the chemical reaction: temperature, pressure, flow rate, reactant concentration, or product concentration.

Claim 17: The method of claim 16, further comprising monitoring one or more of the properties in each of the internal reaction chambers.

Claim 18: The method of claim 1, further comprising adding to one or more of the internal reaction chambers a member selected from the group consisting of an additive, a catalyst, a reactant, and a buffer.

Claim 19: The method of claim 1, wherein the profile of the chemical reaction approximates plug flow or a series of continuous stirred tank reactors.

Claim 20: The method of claim 1, wherein the residence time of a fluid within the reactor, from input to output, is between about 5 minutes to about 16 hours. Claim 21: The method of claim 20, wherein the residence time for the fluid within the reaction chamber is between about 10 hours to about 4 hours.

Claim 22: A method for performing a chemical reaction comprising: (a) substantially continuously inputting one or more chemical reactants into a first end of a reactor such that the one or more reactants proceed from the first end of the reactor to a second end of the reactor, sequentially through two or more internal reaction chambers defined by two or more alternating upper and lower partitions, with minimal back- flow of the chemical reactants;

(b) reacting or splitting the one or more chemical reactants in each of the internal reaction chambers;

(c) bubbling, streaming, or jetting inert gas into each internal reaction chamber to induce turbulent flow of the chemical reactants therein;

(d) substantially uniformly heating the chemical reactants with heat-media filled tubes that each extend through each of the internal reaction chambers; (e) removing vapor from one or more vapor outlets; and

(f) removing an intermediary or a final product from a product outlet proximate to the second end of the reactor. Claim 23: The method of claim 22, wherein the temperature of a fluid within an individual internal reaction chamber is uniform to within about 5 degrees Celsius.

Claim 24: The method of claim 23, wherein the temperature of a fluid within an individual internal reaction chamber is between about 50 degrees

Celsius to about 200 degrees Celsius.

Claim 25: The method of claim 22, wherein the intermediary or the final product is selected from the group consisting of esteramine, biodiesel, betaine, fatty acid, polyol, amine oxide, methyl ester, hydrotrope, and amide.

Claim 26: The method of claim 22, wherein the chemical reaction is selected from the group consisting of esterification, interesterification, transesterification, hydrolysis, alkoxylation, polyesterification, polyamidation, oxidization, halogenation, nitration, sulfonation, amidation, saponification, dehydrogenation, dehydration, dehydrohalogenation, hydrogenalysis, ozonation, etherification, quaternization, and imidazoline formation.

Claim 27: The method of claim 22, wherein the residence time, from input to output, for the fluid is between about 5 minutes to about 10 hours.