WO2009059102A2

WO2009059102A2 - Diesel engine

Info

Publication number: WO2009059102A2
Application number: PCT/US2008/081950
Authority: WO
Inventors: Michael D. Clausen
Original assignee: Parker Hannifin Corp
Current assignee: Parker Hannifin Corp
Priority date: 2007-11-01
Filing date: 2008-10-31
Publication date: 2009-05-07
Anticipated expiration: 2010-05-01
Also published as: US20090113880A1; WO2009059102A3

Abstract

An engine (10) comprising a drain system (80) for removing the fuel-filter-separated water into the engine's exhaust line (61). The fuel-filter-removed water can be directly introduced into the exhaust line (61), and/or it can be directly introduced into a hydrocarbon-dosing line (71) that later merges with the exhaust line (61). A control system (90) can control the fuel-filter-removed-water introduction, such as by adjustment of a valve (84) in the drain line (83), the system (90) and can time such introduction so as to not disturb (and/or to enhance) engine operation.

Description

DIESEL ENGINE

A diesel engine can comprise a fuel system wherein a fuel line extends from a fuel tank to an injection rail adjacent or within the combustion chamber. A fuel filter is usually provided somewhere in the fuel line to remove water from the fuel upstream of the combustion chamber. (See e.g., US7147110.) The fuel- filter-removed water can collect in a sump situated below the filter, and the engine can be provided with a drain system for draining the water from the sump.

SUMMARY

A drain system is provided for introducing fuel-filter-removed water into an exhaust line, whereby it exits an engine through the exhaust pipe. The fuel-filter- removed water can be directly introduced into the exhaust line, and/or it can be directly introduced into a hydrocarbon-dosing line that connects downstream of the exhaust line. In either or any case, the fuel-filter-removed water does not have to be manually drained by an operator, the fuel-filter-removed water is not drained onto the ground, and the fuel-filter-removed water is not returned to the fuel tank.

DRAWINGS

Figures 1 - 4 are each a schematic diagram of an engine wherein a hydrocarbon dosing system receives fuel from a location upstream of fuel injection.

Figure 5 is a schematic diagram of an engine wherein a hydrocarbon dosing system receives fuel from a location downstream of fuel injection.

Figures 6A - 6C are schematic diagrams of fuel-filter-removed water being directly introduced into the exhaust line.

Figures 6D - 6F are schematic diagrams of some pumping devices to aid introduction of the fuel-filter-removed water into the exhaust line. Figures 7A - 7B are schematic diagrams of fuel-filter-removed water being indirectly introduced into the exhaust line via a hydrocarbon-dosing line. Figure 8 is a schematic diagram of an engine control system.

DESCRIPTION

An engine 10, such as the diesel engine schematically shown in Figure 1 , can comprise a combustion system (or chamber) 20, a fuel system 40, an air system 50, and an exhaust system 60.

The combustion chamber 20 can comprise an engine block 21 having multiple (e.g., four) cylinders 22 and pistons 23 mounted for linear motion relative thereto. During operation of the engine 10, each piston 23 repeatedly travels through an intake stroke, a compression stroke, a power stroke, and an exhaust stroke. Each cylinder 22 has an associated air-intake valve 24 that remains closed except during the intake stroke, and an associated exhaust valve 25 that remains closed except during the exhaust stroke. The pistons 23 are connected to a crankshaft 26 that translates the linear motion produced during a power stroke into rotational movement.

The fuel system 40 can comprise a fuel line 41 extending from a fuel tank 42, through a fuel pump 43, through a fuel filter 44, and to a fuel rail 45 within the combustion chamber 20 that feeds fuel injectors 47. A primary role of the fuel filter 44 can be removing water and contaminants from the fuel upstream of the fuel rail 45 and/or combustion chamber 44. The fuel rail 45 holds the pump- pressurized fuel so that the fuel injectors 47 can inject of fuel into each cylinder 22 at the appropriate point in the corresponding piston's stroke cycle (e.g., at the beginning of each power stroke). The fuel pump 43, or another high pressure fuel pump, can instead or alternatively be positioned between the fuel filter 44 and the fuel rail 45.

The air system 50 comprises an air line 51 extending from an intake pipe 52 to an entrance manifold 53 into the combustion chamber 20. The pipe 52 typically intakes ambient (or near ambient) air at atmospheric pressure and weather-dependent temperature. The air line 51 can include a filter 54, a compressor 55, and a throttle 56. A flow meter 57 can be installed in the air line 51 (e.g., near the inlet pipe 52) to measure air intake. The exhaust system 60 can comprise an exhaust line 61 extending from an exit manifold 62 (that communicates with the combustion chamber 20 when an exhaust valve 25 is open) to an exhaust pipe 63. The illustrated engine 10 has a turbocharger design, with a turbine 64 in the exhaust line 61 that lowers exhaust pressure and simultaneously turns the air compressor 55. The exhaust system 60 can further comprise a recirculation line 65 back to the air line 51 and a valve 66 therein to adjust recirculation flow.

The exhaust pipe 63 typically exhausts to the environment, whereby the line 61 can include a pretreatment and/or anti-pollution device. This device can include, for example, an oxidation catalyst 67 and a particulate filter 68. The catalyst 67 converts carbon monoxide pollutants into carbon dioxide, and the filter 68 captures carbon particles still suspended in the catalyst-converted exhaust gas.

The engine 10 can further comprise a hydrocarbon-dosing system 70 for introducing fuel (i.e., hydrocarbon) to the exhaust line 61. Hydrocarbon-dosing can be done, for example, to regenerate the filter 68, by raising the exhaust temperature above the incineration temperature of potentially-clogging carbon particles. Additionally or alternatively, hydrocarbon-dosing can be done to enhance the performance of the catalyst 67 (or other pretreatment or pollution- preventing device), when the engine 10 is running lean.

The hydrocarbon-dosing system 70 can receive fuel from a location upstream of fuel injection (and thus prior to the fuel leaving the fuel line 41 and entering the combustion chamber 20). For example, in Figure 1 , the system 70 comprises a dosing line 71 extending from the fuel tank 42. In Figure 2, the dosing line 71 extends from the fuel line 41 at the discharge side of the fuel pump 44. In Figure 3, the dosing line 71 extends from the fuel line 41 downstream of the filter 44. In Figure 4, the dosing line 71 extends from the fuel rail 45 (prior to it being injected by the switches 47). When the system 70 includes a dosing line 71 , it can also include a valve 72 to control flow therethrough. The hydrocarbon-dosing system 70 can additionally or alternatively receive fuel from a location downstream of fuel injection. Specifically, for example, the fuel injectors 47 can be used to also inject hydrocarbons into the exhaust gas prior to it exiting into the manifold 62. With in-cylinder dosing, for example, fuel is injected into the cylinder 22 during the exhaust stroke of the piston 23. As shown schematically in Figure 5, this results in the fuel system 40 and the hydrocarbon-dosing system 70 using the same equipment and components, without the need for a separate dosing line 71 or valve 72.

The engine 10 can further comprise a drain system 80 for draining fuel- filter-removed water from a sump 81 associated with (e.g., positioned below) the fuel filter 44 in the fuel line 44. A level indicator 82 (or other water-quantity sensor) can be used to monitor the amount of water within the sump 81.

The drain system 80 can include a drain line 83 extending from the sump

81 and a valve 84 for opening/closing this drain line 83. The drain line 83 is routed so that the fuel-filter-removed water eventually enters the exhaust line 61 and joins with the exhaust gas traveling therethrough. To this end, the drain line

82 can be directly plumbed to the exhaust line (61), and/or it can be routed through a dosing line 72.

The drain line 82 is schematically shown connected to the exhaust line 61 in Figures 6A - 6C, whereby drain water is introduced directly to the exhaust gas. The drain water can, for example, be introduced downstream of the filter 68 (Figure 6A), downstream of the turbine 63 and upstream of the catalyst 67 (Figure 6B), and/or upstream of the turbine 63 (Figure 6C). In the first scenario (Figure 6A), the drain water may desirably lower the final exhaust temperature of the engine 10, but it will not pass through the catalyst 67 or filter 68. In the latter two scenarios (Figures 6B and 6C), the drain water passes through the anti- pollution devices 6B/6C, but it may lower catalyst inlet temperature which may not be desirable during regeneration efforts. With post-turbine introduction of the drain water (Figures 6A and 6B), the exhaust gas is at a significantly lower pressure than with pre-turbine introduction (Figure 6C). The pressure of the drain water will probably be less than the pressure of the exhaust line 61 along its various stages. Accordingly, the drain system 80 may comprise a pumping device or means for encouraging the introduction of the fuel-filter-removed water into the exhaust line 61. For example, the drain system 80 can include a dedicated pump 85 for this purpose, as shown schematically in Figure 6D. Additionally or alternatively, if fuel-filter-removed- water introduction occurs downstream of the turbine 63, it may be possible to take advantage of the exhaust pressure to aid in water induction into the line 61. For example, as shown in Figure 6E, water-pumping vanes 86 can be turned by the turbocharger drive train (e.g., the turbine 63), and/or, as shown in Figure 6F, exhaust bleed can be use as the motive fluid in a venturi device 87.

The drain line 82 can additionally or alternatively be plumbed to the hydrocarbon dosing line 71 upstream of its connection to the exhaust line 61 , as shown schematically in Figures 7A and 7B. In most instances, the hydrocarbon dosing line 71 will be connected to the exhaust line 61 upstream of the catalyst 67, whereby the fuel-filter-removed water will be introduced upstream of the catalyst. In other words, the drain line 82 could essentially be the hydrocarbon dosing line 71 , with the water being expelled during normal dosing cycles. This could be accomplished by, for example, the hydrocarbon dosing line 71 being supplied from the bottom of the fuel filter 44, so that any collected water is automatically expelled into the exhaust gas.

The engine 10 can further comprise a system 90 for controlling the operation of the engine 10. The control 90 can comprise, for example, a microcomputer (or a plurality of microcomputers having an input interface 91 , a processor 92, and an output interface 93. The input interface 91 can receive engine-operating information through input lines 100, the processor 92 can process this input to determine optimum operating conditions, and the output interface 93 can provide engine-operating instructions through output lines 200. As shown schematically in Figure 8, the control system 90 can receive input information regarding crankshaft rotation (input line 125), fuel tank level (input line 142), air intake flow (input line 157), exhaust manifold temperature (input line 162), final exhaust temperature (input line 163), post-turbine exhaust temperature (input line 164), post-catalyst temperature (input line 167), filter pressure drop (input line 168), and/or sump water level (input line 182). Based on some or all of these inputs, the control system 90 can provide operating instructions to the air-intake valves 24 (output line 224), the exhaust valves 25 (output line 225), the fuel pump 43 (output line 243), fuel injectors 47 (output line 247), air throttle 56 (output line 256), recirculation valve 66 (output line 266), dosing valve 72 (output line 272), drain valve 84 (output line 284), drain pump 86 (output line 285), and/or drain venture device 87 (output line 287). The control system 90 can be used to initiate introduction of fuel-filter- removed water from the sump 81 into the exhaust line 61. The system 90 can, for example, determine that drainage is necessary based on the water level in the sump 81 (via input line 182). The drain valve 72 can be opened via the output line 272 and, if applicable, the drain pump 85 activated and/or the venturi- device valves 87 adjusted via output lines 285 /287.

The control system 90 can time introduction of the fuel-filter-removed water so as to not disturb, and perhaps to enhance, engine operation. For example, if water introduction will have a cooling effect, it can be initiated upon sensing (via input line 163) that final exhaust temperature is above a desirable range. Water introduction could be used to enhance catalyst conversion when deemed appropriate by temperature inputs through line 164 and/or line 167. Additionally or alternatively, water introduction could be coordinated with hydrocarbon dosing and correlated with the opening of dosing valve 72 (via output line 272) or fuel dosing fuel injection (via output line 247). That being said, such elaborate system-control coordination of the drain system 80 with the rest of the engine systems may not be necessary. The control of the drain system 80 could be as simple as metering the sump water into the exhaust line 61 at a predetermined rate and/or preset intervals. Check valves and mechanical thermostats could be used to prevent engine-interrupting issues. Such a simpler incorporation might be desirable if the engine 10 is to be retrofitted with the drain system 80, as it will not require replacement and/or reprogramming of the existing engine control system 90.

If the drain line 82 is also the hydrocarbon dosing line 71 (or vice-a- versa), the draining of fuel-filter-removed water can be controlled by the hydrocarbon-dosing logic of the system 90. For example, if hydrocarbon dosing is needed (e.g., a high pressure drop is sensed across the exhaust filter 68), the drain valve 84 can be opened. As the fuel-filter-removed water is draining through the line 71/82, regeneration may not occur. But the process can be repeated until the drain water is gone (e.g., as measured by sensor 82). The dosing valve 72 can remain closed until water draining is complete (or the fuel injections 47 can delay injecting fuel into the exhaust gas), and thereafter the dosing fuel supplied to cause regeneration of the exhaust filter 68.

One may now appreciate that with the engine 10 and/or the drain system 80, fuel-filter-removed water does not have to be drained manually from the sump 81, the water is not drained onto the ground, and the water is not returned to the fuel tank 42. Although the engine 10, the systems 20, 40, 50, 60, 70, 80, 90, and/or related components, methods, or steps have been shown and described with respect to certain embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In regard to the various functions performed by the above described elements (e.g., components, assemblies, systems, devices, compositions, etc.), the terms (including a reference to a "means") used to describe such elements are intended to correspond, unless otherwise indicated, to any element which performs the specified function of the described element (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function. In addition, while a particular feature of the invention may have been described above with respect to only one or more of several illustrated embodiments, such feature may be combined with one or more other features of the other embodiments, as may be desired and advantageous for any given or particular application.

Claims

1. A drain system (80) for use in an engine (10) comprising a combustion chamber (20), a fuel system (40) comprising a fuel line (41) for supplying fuel to the combustion chamber (20) and having a fuel filter (44) for separating water from fuel upstream of the combustion chamber (20), and an exhaust line (61) for exhausting the combustion chamber (20); wherein the drain system (80) introduces water separated by the fuel filter (44) into the exhaust line (61).

2. A drain system (80) as set forth in the preceding claim, comprising a drain line (82) and a valve (83) for adjusting flow through the drain line (82).

3. A drain system (80) as set forth in either of the two preceding claims, wherein the fuel-filter-separated water is collected in a sump (81) adjacent the fuel filter (44).

4. A drain system (80) as set forth in the preceding claim, wherein the sump (81) is positioned below the fuel filter (44).

5. A drain system (80) as set forth in either of the two preceding claims, comprising a sensor (84) for sensing the amount of water in the sump (81).

6. A drain system (80) as set forth in the preceding claim, wherein the sensor (84) is a level indicator.

7. A drain system (80) as set forth in any of the preceding claims, wherein a/the drain line (82) extends from a/the sump (81).

8. A drain system (80) as set forth in any of the preceding claims, comprising pump means (85, 86, 87) to aid introduction of the fuel-filter-removed water to the exhaust line (61).

9. A drain system (80) as set forth in claim 8, wherein the pump means comprises a dedicated pump (85).

10. A drain system (80) as set forth in claim 8, wherein the pump means comprises pumping vanes (96) turned by turbocharger components.

11. A drain system (80) as set forth in claim 8, wherein the pump means comprises a venturi device using bleed from the exhaust line (61) as motive fluid.

12. A drain system (80) as set forth in claim 1 , wherein the fuel-filter- separated water is introduced directly into the exhaust line (61).

13. A drain system (80) as set forth in the preceding claim, wherein the fuel-filter-separated water is introduced into the exhaust line (61) upstream of an exhaust pipe (63) through which the exhaust line (61) exhausts to the environment.

14. A drain system (80) as set forth in either of the two preceding claims, wherein the fuel-filter-separated water is introduced into the exhaust line (61) downstream of an outlet manifold (62) from the combustion chamber (20).

15. A drain system (80) as set forth in any of claims 12 - 14, wherein the fuel-filter-separated water is introduced into the exhaust line (61) upstream of a turbine (64) in the exhaust line (61).

16. A drain system (80) as set forth in any of claims 12 - 14, wherein the fuel-filter-separated water is introduced into the exhaust line (61) downstream of a turbine (64) in the exhaust line (61).

17. A drain system (80) as set forth in any of claims 12 - 14, wherein the fuel-filter-separated water is introduced into the exhaust line (61) upstream of a recirculation line (65) extending from the exhaust line (61) to an air line (51).

18. A drain system (80) as set forth in the preceding claim, wherein the recirculation line (65) is closed during introduction of the fuel-filter-separated water into the exhaust line (61) to prevent the water from migrating to the air line (51).

19. A drain system (80) as set forth in the preceding claim, wherein a valve (66) in the recirculation line (65) is closed during introduction of the fuel- filter-separated water into the exhaust line (61).

20. A drain system (80) as set forth in any of claims 12 - 14, wherein the fuel-filter-separated water is introduced into the exhaust line (61) downstream of a recirculation line (65) extending from the exhaust line (61) to an air line (51).

21. A drain system (80) as set forth in any of claims 12 - 14, wherein the fuel-filter-separated water is introduced into the exhaust line (61) downstream of a pollution device (67,68) in the exhaust line (61).

22. A drain system (80) as set forth in any of claims 12 - 14, wherein the fuel-filter-separated water is introduced into the exhaust line (61) upstream of a pollution device (67,68) in the exhaust line (61).

23. A drain system (80) as set forth in either of the two preceding claims, wherein the pollution-preventing device includes an oxidation catalyst (67).

24. A drain system (80) as set forth in any of the three preceding claims, wherein the pollution-preventing device includes a particulate filter (68).

25. A drain system (80) as set forth in the preceding claim, wherein the filter (68) is positioned downstream of a/the catalyst (67).

26. A drain system (80) as set forth in claim 1 , wherein the fuel-filter- separated water is introduced into a line (71) connected to the exhaust line (61) whereby the fuel-filter-separated water is introduced indirectly into the exhaust line (61).

27. An drain system (80) as set forth in the preceding claim, wherein the line (71) is a part of a hydrocarbon-dosing system (70) that introduces fuel to the exhaust line (61).

28. A drain system (80) as set forth in claim 1 , wherein the engine (10) includes a hydrocarbon-dosing system (70) that doses fuel into the exhaust line (61), and wherein the introduction of the fuel-filter-removed water to the exhaust line (61) is correlated with the dosing of fuel into the exhaust line (61).

29. An engine (10) comprising: a combustion chamber (20); a fuel system (40) comprising a fuel line (41) for supplying fuel to the combustion chamber (20) and having a fuel filter (44) for separating water from fuel upstream of the combustion chamber (20); an exhaust line (61) for exhausting the combustion chamber (20); and a drain system (80) as set forth in any of claims 1 - 28.

30. A diesel engine (10) comprising: a combustion chamber (20); a fuel system (40) comprising a fuel line (41) for supplying fuel to the combustion chamber (20) and having a fuel filter (44) for separating water from fuel upstream of the combustion chamber (20); an exhaust line (61) for exhausting the combustion chamber (20); and a drain system (80) as set forth in any of claims 1 - 28.

31. An engine (10) as set forth in either claim 29 or claim 30, wherein the combustion chamber (20) comprises a cylinder (22) and a piston (23) mounted for linear motion relative thereto.

32. An engine (10) as set forth in the preceding claim, wherein the combustion chamber (20) comprises multiple cylinders (22) and a piston (23) mounted for linear motion relative to each cylinder (22).

33. An engine (10) as set forth in the preceding claim, wherein the combustion chamber (20) comprises four cylinders (22) and four pistons (23).

34. An engine (10) as set forth in any of claims 31 - 33, wherein the combustion chamber (20) comprises an engine block (21) in which each cylinder (22) is formed.

35. An engine (10) as set forth in any of claims 31 - 33, wherein each piston (23) repeatedly travels through an air-intake stroke, an air-compression- stroke, a power stroke, and an exhaust stroke.

36. An engine (10) as set forth in the preceding claim, wherein each cylinder (22) has an air-intake valve (24) that remains closed except during the intake stroke.

37. An engine (10) as set forth in either of the two preceding claims, wherein each cylinder (22) has an exhaust valve (25) that remains closed except during the exhaust stroke.

38. An engine (10) as set forth in any of the claims 31 - 37, wherein each piston (23) is connected to crankshaft (26) that translates linear motion into rotational motion during power strokes.

39. An engine (10) as set forth in any of claims 31 - 38, wherein the fuel system (40) comprises a fuel tank (42) and wherein the fuel line (41) extends from the fuel tank (42).

40. An engine (10) as set forth in the preceding claim, wherein the fuel system (40) comprises an injection rail (45) within the combustion chamber (20) and wherein the fuel line (41) extends from the fuel tank (42) to the injection rail (45).

41. An engine (10) as set forth in the preceding claim, wherein the fuel system (40) comprises fuel injectors (47) fed by the injection rail (45).

42. An engine (10) as set forth in any of claims 39 - 41 , wherein the fuel system (40) comprises a fuel pump (43) downstream of the fuel tank (42).

43. An engine (10) as set forth in the preceding claim, wherein the fuel pump (43) is positioned upstream of the fuel filter (44).

44. An engine (10) as set forth in any of claims 29 - 43, wherein the exhaust system (60) comprises an exhaust manifold (62) that receives exhaust gas from the combustion chamber (20) and wherein the exhaust line (61) extends from the exhaust manifold (62) to an/the exhaust pipe (63).

45. An engine (10) as set forth in the preceding claim, wherein the exhaust pipe (63) exhausts to the environment.

46. An engine (10) as set forth in any of claims 29 - 44, wherein the exhaust system (60) comprises a turbine (64) in the exhaust line (61).

47. An engine (10) as set forth in the preceding claim, wherein the turbine (64) turns an air compressor (54).

48. An engine (10) as set forth in any of claims 29- 47, wherein the exhaust system (60) comprises a recirculation line (65) extending from the exhaust line (61) to an air line (51 ).

49. An engine (10) as set forth in the preceding claim, wherein the exhaust system (60) includes a valve (66) for adjusting the flow through the recirculation line (65).

50. An engine (10) as set forth in any of claims 29 - 49, wherein the exhaust system (60) includes a pollution device (67,68) in the exhaust line (61).

51. An engine (10) as set forth in the preceding claim, wherein the pollution-preventing device includes an oxidation catalyst (67).

52. An engine (10) as set forth in either of the two preceding claims, wherein the pollution-preventing device includes a particulate filter (68).

53. An engine (10) as set forth in the preceding claim, wherein the filter (68) is positioned downstream of a/the catalyst (67).

54. An engine (10) as set forth in any of claims 29 - 53, further comprising an air system (50) for supplying air to the combustion chamber (20).

55. An engine (10) as set forth in the preceding claim, wherein the air system (50) comprises an air line (51) extending from an air intake pipe (51) to an inlet manifold (53) to the combustion chamber (20).

56. An engine (10) as set forth in the preceding claim, wherein the air system (50) comprises a throttle (56) for adjusting flow through the air line (51).

57. An engine (10) as set forth in either of the two preceding claims, wherein the air system (50) comprises a filter (55) in the air line (51) upstream of the inlet manifold (53).

58. An engine (10) as set forth in any of the three preceding claims, wherein the air system (50) comprises a compressor (54) in the air line (51) upstream of the inlet manifold (53).

59. An engine (10) as set forth in any of claims 54 - 58, wherein the air system (50) comprises a meter (57) for measuring flow through the air line (51).

60. An engine (10) as set forth in any of claims 29 - 59, further comprising a hydrocarbon-dosing system (70) that introduces fuel to the exhaust line (61).

61. An engine (10) as set forth in claim 60, wherein the hydrocarbon- dosing system (70) comprises a dosing line (71) receiving fuel from a location upstream of the combustion chamber (20).

62. An engine (10) as set forth in the preceding claim, wherein the dosing system (70) comprises a valve (72) for adjusting flow through the dosing line (71).

63. An engine (10) as set forth in claim 61 or claim 62, wherein the dosing line (71) extends from a/the fuel tank (42) to the exhaust line (61).

64. An engine (10) as set forth in claim 61 or claim 62, wherein fuel system (40) comprises a fuel pump (43) and wherein the dosing line (71) extends from the discharge side of a/the fuel pump (43) to the exhaust line (61).

65. An engine (10) as set forth in claim 61 or claim 62, wherein the dosing line (71) extends from the fuel line (41) downstream of the fuel filter (44), to the exhaust line (61).

66. An engine (10) as set forth in claim 61 or claim 62, wherein the dosing line (71) extends from an/the injection rail (45) to the exhaust line (61).

67. An engine (10) as set forth in any of claims 62 - 66, wherein the dosing line (71) connects to the exhaust line (61) upstream of a/the pollution- preventing device (67,68).

68. An engine (10) as set forth in claim 60, wherein the hydrocarbon- dosing system (70) receives fuel from a location downstream of the fuel line (41).

69. An engine (10) as set forth in the preceding claim, wherein fuel injectors (47) inject hydrocarbons into the exhaust gas prior to it exiting a/the exhaust manifold (62).

70. An engine (10) as set forth in any of claims 29 - 69, further comprising a control system (90) for controlling engine operation.

71. An engine (10) as set forth in the preceding claim, wherein the control system (90) comprises an input interface (91) for receipt of engine- operating information, a processor (92) for processing the input engine-operating information and determining optimum operating conditions, and an output interface (93) for providing engine-operating instructions.

72. An engine (10) as set forth in either of the two preceding claims, wherein the control system (90) receives input information regarding crankshaft rotation, fuel tank level, air intake flow, exhaust manifold temperature, final exhaust temperature, post-turbine temperature, post-catalyst temperature, filter pressure drop, and/or sump water level.

73. An engine (10) as set forth in any of the three preceding claims, wherein the control system (90) provides output instructions to air-intake valves (24), exhaust valves (25), a/the fuel pump (43), a/the air throttle (56), a/the recirculation valve (66), a/the dosing valve (72), a/the drain valve (84), a/the drain pump (86), and/or a/the drain venturi device (87).

74. An engine (10) as set forth in any of claims 70 - 73, wherein the control system (90) is programmed to initiate introduction of the fuel-filter- removed water into the exhaust line (61).

75. An engine (10) as set forth in any of claims 70 - 74, wherein the control system (90) is programmed to determine whether drainage of fuel-filter- removed water is necessary based on water level in a/the sump (81).

76. An engine (10) as set forth in any of claims 70 - 75, wherein the control system (90) is programmed to adjusts a/the drain valve (72) to control introduction of fuel-filter-removed water into the exhaust line (61).

77. An engine (10) as set forth in any of claims 70 - 76, wherein control system (90) is programmed to activate pump means (84, 86, 87) to aid introduction of the fuel-filter-removed water to the exhaust line (61).

78. An engine (10) as set forth in any of claims 70 - 77, wherein the control system (90) is programmed to time introduction of the fuel-filter-removed water into the exhaust line (61) so as to not disturb engine operation.

79. An engine (10) as set forth in any of claims 70 - 78, wherein the control system (90) is programmed to time introduction of the fuel-filter-removed water into the exhaust line (61) so as to enhance engine operation.

80. An engine (10) as set forth in any of claims 70 - 79, wherein the control system (90) is programmed to initiate introduction of the fuel-filter- removed water into the exhaust line (61) when final exhaust temperature is above a desirable range.

81. An engine (10) as set forth in any of claims 70 -80, wherein the control system (90) is programmed to initiate introduction of the fuel-filter- removed water into the exhaust line (61) to improve catalyst reactions.

82. An engine (10) as set forth in any of claims 70 - 81 , wherein the control system (90) is programmed to coordinate introduction of the fuel-filter- removed water with hydrocarbon dosing.

83. An engine (10) as set forth in any of claims 29 - 73, wherein control of the drain system (80) is independent of control of the combustion chamber (20), the fuel system (40), and/or the exhaust system (60).

84. A drain system (80) for introducing water to an exhaust line (61).

85. An engine (10) wherein filter-separated water is introduced to an exhaust line (61).

86. A drain system (80) for introducing filter-separated water into a line

(61 ,71) of another system (60,70) of an engine (10).

87. A drain system (80) for introducing water into a hydrocarbon- dosing line (71).

88. An engine (10) wherein water is introduced into a hydrocarbon- dosing line (71).

89. An engine (10) as set forth in the preceding claim, wherein the hydrocarbon dosing line (71) is also the drain line (82) from a fuel filter (44), whereby fuel-filter-removed water is automatically removed during hydrocarbon dosing.