JP6167099B2 - Fuel oil supply device for diesel engine - Google Patents

Description

  The present invention relates to a fuel oil supply device for a diesel engine, and more particularly, a diesel that can be used as a fuel oil even in a vegetable oil such as palm stearin that is known to be non-flowable at room temperature among vegetable oils. The present invention relates to an engine fuel oil supply device.

  Palm oil collected from oil palm has the largest production amount among vegetable oils (oils and fats) by removing soybean oil. Crude palm oil is refined (for example, fractionation using a difference in melting point), and RBD (Refined, Bleached and Deodorized) palm olein of the refined liquid part is obtained. RBD palm stearin has been created.

  The stearin and olein mentioned here do not refer to stearic acid and oleic acid, but are fixed as industry-specific terms called stearin for solids and olein for liquids. According to the JAS standard, palm stearin is clear at 60 ° C., and palm olein is clear at 40 ° C.

  Among such vegetable oils, high pour point vegetable oils typified by palm stearin generally have a molecular weight of 3 times higher than that of light oil or heavy oil A, and have a high evaporation temperature. When it is low, the fuel is difficult to burn completely. In addition, there are some in which the pour point temperature changes drastically due to the difference in the mixing ratio of the fatty acid contained depending on the source plant and the production area, and rapidly solidifies even at a high temperature. It is said that the vegetable oil containing a lot of unsaturated fatty acids undergoes rapid oxidative degradation due to heating, and generally the oxidative degradation rate doubles as the oil temperature rises by 10 ° C. Furthermore, the thermal conductivity of vegetable oil is about 1/4 that of water, and it is difficult to heat it uniformly.

  As a fuel supply device for an engine using vegetable oil, the following Patent Document 1 can be cited, and it is mixed and supplied with a high fluidity and heat resistant low pour point fuel selected from A heavy oil, kerosene, and light oil. The high pour point vegetable oil such as palm stearin cannot be supplied alone to the engine.

  High-viscosity diesel fuel oils that are widely used at present include C heavy oil and HPP. As exemplified in the following Patent Documents 2 to 7, many proposals have been made from various technical viewpoints regarding a fuel supply device for a diesel engine that uses a high viscosity fuel oil such as C heavy oil.

  However, these high-viscosity fuel oils such as C heavy oil can be transferred and supplied by heating and keeping the fuel oil to a viscosity that can be easily transferred. Therefore, there is no practical problem with the approximate oil temperature management in the tank with respect to the storage in the tank or the like. C heavy oil is a Newtonian fluid and is easy to handle.

  Therefore, in a conventional diesel engine fuel oil supply apparatus for C heavy oil or HPP, a high pour point vegetable oil such as palm stearin that exhibits the characteristics of a non-Newtonian fluid cannot be supplied to the engine alone.

Japanese Patent No. 4966828 Japanese Patent No. 2710363 Japanese Utility Model Publication No. 58-34280 Japanese Patent Publication No. 60-47470 Japanese Utility Model Publication No.59-126168 Japanese Utility Model Publication No. 58-134671 JP 2002-310027 A

  In the case of refined palm stearin (RBDPS), it solidifies and loses fluidity at a temperature of about 50 to 55 ° C. or less, and the optimum fuel spray temperature is 80 to 85 ° C. (about 12 cSt). Compared to a settling tank temperature of 60 ° C and a fuel spray optimum temperature of 125 ° C (about 12cSt) for common C heavy oil (180cSt at 50 ° C), palm stearin is solidified despite solidifying at a considerably high temperature. The difference between the start temperature and the optimum fuel spray temperature is 30 ° C. That is, the difference in temperature between the settling tank temperature of general C heavy oil and the optimum fuel spray temperature of 65 ° C. is half, and it can be seen that the handling is difficult.

  In addition, if there is a local temperature drop in the fuel oil piping system during engine operation such as in winter when the outside air temperature is low, the viscosity of the vegetable oil will increase and solidification will occur, making it difficult to transfer and supply the fuel, causing the engine to stop. It will end up. In addition, if the engine is stopped urgently while operating with such vegetable oil, the engine will stop with such vegetable oil remaining in the fuel oil piping, and if the temperature of the engine drops to room temperature in this state In order to restart the engine, if the entire fuel oil piping system is not heated to about 60 ° C. or cleaned, the next start is impossible and it takes a long time to restart.

  Furthermore, in order to use vegetable oil having such characteristics as fuel for diesel engines, it is heated uniformly with the minimum necessary heating to suppress oxidative degradation and transfer and supply. Therefore, it is necessary to prevent solidification due to a significant temperature drop, and to prevent oxidative deterioration due to overheating and resinification due to polymerization.

  In the case of an engine that uses DSS (Daily start and stop), the engine will be stopped at night, but the engine will be restarted the next morning. It is necessary to continue to prevent the vegetable oil from solidifying by cooling.

  In summary, in the case of a high pour point vegetable oil represented by palm stearin, the temperature difference between the pour point and the appropriate injection temperature is small, so the temperature control of the vegetable oil in the fuel supply system is delicate, and polymerization solidification due to overheating. In addition, there is a problem due to solidification due to insufficient heating, and it is necessary to try to solve these problems.

  The present invention has been made in view of various problems in the background art described above, and is a diesel engine fuel oil supply device that can be used alone without any problems even if it is a high pour point vegetable oil typified by palm stearin. It is intended to provide.

  Means for solving the problems will be described based on the description of each claim of the present invention. In addition, the definition of each constituent element constituting the means for solving the problem will be described as necessary. These definitions are the same as the definitions of the terms in the “DETAILED DESCRIPTION”. In the description of the means for solving the problems, the reference numerals indicating the respective components are used in the “DETAILED DESCRIPTION OF THE EMBODIMENTS” for convenience, but this limits the technical scope of the present invention to the contents of the embodiments. Does not mean to do. The use of reference signs in the “effects” described later in this section has the same meaning.

A fuel oil supply device for a diesel engine according to claim 1,
From the fuel circulation tank (1) to the fuel injection pump (18) of the diesel engine (3) through the supply pump (2), high pour point vegetable oil that is not fluid at normal temperature is supplied, and the excess high pour point vegetable oil is supplied to the fuel injection pump (18). A diesel engine fuel supply circuit (4) returning to the fuel circulation tank;
A fuel oil drain tank (30) having heating means (31) and communicating with the atmosphere, and a drain path (32) with a downward slope from the fuel circulation tank to the fuel oil drain tank;
A drain path (33) with a downward slope extending from the diesel engine fuel supply circulation path to the fuel oil drain tank;
A return path (36) for feeding high pour point vegetable oil, which is drain, from the fuel oil drain tank to the fuel circulation tank via a pump (34) and a check valve (35);
It is characterized by having.

  The drain of the present invention refers to the fuel oil in the case where the remaining fuel oil is discharged from the tank, equipment, passage or pipeline of the fuel oil supply device of the diesel engine for the stop and maintenance of the diesel engine (3). In other words, it does not include those that are open to the atmosphere and contaminated with dust, or those that cannot be used as fuel oil for diesel engines due to the mixing of steam from steam cleaning.

  The drain path from the diesel engine fuel supply circuit (4) is a drain path branched from the pipe of the diesel engine fuel supply circuit itself, as well as from the equipment interposed in the diesel engine fuel supply circuit Including the drain road. Naturally, a valve for partitioning from the diesel engine fuel supply circulation path and the fuel circulation tank is provided at the base of each drain path.

  The diesel engine fuel supply circuit (4) including the fuel circulation tank (1) is a closed system, whereas the fuel oil drain tank (30) has an intake / exhaust pipe communicating with the outside air. And an open system including the drain path.

  The drain channel (32, 33) with a downward gradient is a gradient formed so that the high pour point vegetable oil, which is a drain, flows by gravity (gravity feed gravity feed). The drain is formed so as to prevent the drain from flowing due to gravity after the upward slope, and the drain where substantially high pour point vegetable oil flows into the fuel oil drain tank (30) by gravity. Say the road.

  It is preferable that steam drains or electric heaters are provided along all drain paths (32, 33) so as to be heated and kept warm.

The fuel oil supply device for a diesel engine according to claim 2 is the fuel oil supply device for a diesel engine according to claim 1,
A set pressure of a return path (36) for feeding high pour point vegetable oil as drain from the fuel oil drain tank (30) to the fuel circulation tank (1) through a pump (34) and a check valve (35). At a pressure lower than the primary set pressure of the first pressure regulating valve (13) provided in the return path (4b) of the diesel engine fuel supply circulation path (4) and is supplied to the fuel circulation tank. It is characterized in that the pressure is higher than the supply pressure of the high pour point vegetable oil and low pour point oil.

The fuel oil supply device for a diesel engine according to claim 3 is the fuel oil supply device for a diesel engine according to claim 1 or 2,
An exhaust path (38) from the head of the fuel circulation tank (1) to the fuel oil drain tank via an automatic exhaust valve (37) is provided.

  The automatic exhaust valve (37) is also referred to as an automatic air vent valve, and is a valve that automatically exhausts a gas body accumulated during operation in a liquid system under an operating pressure, and is often a float type. A product of model VS1C made by the company can be preferably used.

The fuel oil supply device for a diesel engine described in claim 4 is the fuel oil supply device for a diesel engine according to any one of claims 1 to 3,
A static mixer (29) is interposed in the diesel engine fuel supply circuit (4).

According to the diesel engine fuel oil supply apparatus of the first aspect, the following effects can be obtained.
The fuel oil drain from the fuel circulation tank (1) side and the high pour point vegetable oil drain from the diesel engine fuel supply circulation path (4) side both have a downward slope reaching the fuel oil drain tank (30). It is collected in the fuel oil drain tank (30) communicating with the atmosphere provided with the heating means (31) through the attached drain passages (32, 33), and via the pump (34) and the check valve (35). Oil is fed from the return path (36) to the fuel circulation tank (1) and is reused.

According to the diesel engine fuel oil supply apparatus of the second aspect, the following effects can be obtained.
That is, when compared with the set pressure of the return path (36) for feeding the high pour point vegetable oil as drain from the fuel oil drain tank (30) to the fuel circulation tank (1), the diesel engine fuel supply circulation path (4 The primary side of the first pressure regulating valve (13) provided in the return path (4b) is a relatively high pressure region, and new high pour point vegetable oil and low pour point oil are supplied to the fuel circulation tank (1). Since the supply side is a relatively low pressure region, the high pour point vegetable oil, which is a drain, is smoothly supplied from the fuel oil drain tank (30) to the fuel circulation tank (1) through the return path (36). Can be sent.

According to the diesel engine fuel oil supply apparatus of the third aspect, the following effects can be obtained.
The gas accumulated in the fuel circulation tank (1) is discharged out of the system via the automatic exhaust valve (37), but is communicated with the atmosphere via the fuel oil drain tank (30), and thus entrained in the air. Fuel oil does not scatter into the atmosphere. Further, the fuel oil remaining in the tank, equipment, passage or pipe of the fuel oil supply device of the diesel engine (3) via the drain passage (32, 33) for the purpose of stopping and maintaining the diesel engine (3). Is discharged to the fuel oil drain tank (30), the automatic exhaust valve (37) operates as a vacuum break valve, and the fuel oil drain tank (1) is connected to the closed fuel circulation tank (1). 30) and the air through the automatic exhaust valve (37), the fuel oil can be smoothly discharged into the fuel oil drain tank (30).

According to the diesel engine fuel oil supply apparatus of the fourth aspect, the following effects can be obtained.
Since the high pour point vegetable oil flowing through the diesel engine fuel supply circuit (4) is further fluidized and agitated by the static mixer (29), the characteristics of the non-Newtonian fluid whose viscosity is further lowered by making it into a fluid state can be obtained. Since the high pour point vegetable oil shown can be made even lower in viscosity, it is possible to easily obtain the viscosity necessary for supplying to the diesel engine (3).

As described above, the vegetable oil targeted by the present invention is mainly composed of high-molecular weight saturated fatty acids and solidifies at room temperature. When such a vegetable oil is used as a fuel oil for a diesel engine, the ignitability is better than that of A heavy oil or the like, but the burn-out period tends to be longer because the molecular weight is large and the evaporation temperature is high. In order to improve the economy by completely burning such fuel oil to prevent engine contamination and maintaining good engine performance, it is necessary to switch to vegetable oil for operation while the engine is sufficiently warmed up. . Therefore, the engine is started with fuels with low viscosity and good flammability even at room temperature, such as heavy oil A or BDF, and the engine is operated with those fuels up to about 50% load. It is preferable to operate by switching. In the case of vegetable oil that solidifies at room temperature, fuel blockage due to the solidification of the vegetable oil occurs when a low temperature portion is partially generated in the fuel pipe. Furthermore, normally, when the engine is urgently stopped, it is difficult to restart unless the residual vegetable oil in the fuel oil pipe is discharged. However, by adopting the configuration of the present invention as described above, the vegetable oil is contained in the pipe. It is possible to easily cope with solidification so as not to cause clogging, and carbon-free operation with substantially no CO ₂ emission (carbon-free power generation when used for power generation) becomes possible.

It is a figure which shows the half part of the whole block diagram of embodiment of this invention. It is a figure which shows the other half part of the whole block diagram of embodiment of this invention. FIGS. (A) and (b) are views showing an attachment state of bypass pipes used for attachment of various devices for the purpose of maintenance or the like in the embodiment of the present invention, and (a) is a perspective view. Yes, a fraction (b) is a side view thereof. Divided views (c) and (d) are views showing an attachment state of a bypass pipe different from the embodiment of the present invention, divided view (c) is a perspective view, and divided view (d) is a side view thereof. is there. It is a figure which shows the high pressure gas supply connection port etc. which were provided in the fuel oil circulation main pipe end part inside the engine which comprises a part of diesel engine fuel supply circulation path in embodiment of this invention, and fraction (a) is a plane FIG. 2 is a front view, and FIG. 2C is a cross-sectional view taken along a cutting line A in FIG. It is a figure which shows the drain piping system connected to the fuel injection valve in embodiment of this invention. The cross-sectional view which shows that the termination | terminus of the return path to the high pour point vegetable oil tank of the high pour point vegetable oil circulation path in the embodiment of the present invention is branched and opened in the high pour point vegetable oil tank (upper side) 2 is a sectional view) and a longitudinal sectional view (bottom sectional view).

1. Description of Outline of Embodiment An outline of the embodiment will be described with reference to FIGS. 1 and 2.
FIG. 1 and FIG. 2 are combined drawings showing an enlarged single configuration diagram divided into two, and are cases where they appear in either one of the drawings when referred to in the following description. However, it is expressed as “as shown in FIG. 1 and FIG.
In addition, although the name of each structural requirement of embodiment described below may not necessarily correspond with the name of each structural requirement of each invention described in the claims, this is the same structural requirement. It is merely a difference in expression that occurs when viewed as a part of a more abstract technical idea and as a part of a more specific mechanical device, etc., indicating that both names are substantially different. The corresponding constituent elements shall be given the same reference as much as possible.

  In this embodiment, the object is to solve the above-mentioned problem, and even when vegetable oil that does not flow at room temperature is used, a local temperature drop portion does not occur in the fuel oil piping system, and there is no fluidity at room temperature. An object of the present invention is to provide a fuel oil piping system capable of preventing the vegetable oil from coagulating and causing clogging in the fuel oil piping system even when the engine is stopped urgently during operation with the vegetable oil.

  For the reasons described above, the fuel oil piping system of the diesel engine 3 that uses vegetable oil includes a storage tank side fuel oil piping system 9 (high pour point vegetable oil circulation path 9) from the vegetable oil storage tank 7 to the fuel oil switching valve 50. ) And the diesel engine fuel supply circuit 4 (4a, 4b) are separated into two systems, and the entire fuel piping system is kept at a uniform temperature as a complete circulation system in which no fuel oil stays in each piping system. be able to. In particular, with respect to the diesel engine fuel supply circuit 4 (4a, 4b), the diesel engine fuel supply circuit is switched to a low-viscosity oil such as A heavy oil or BDF (biodiesel fuel) before the engine is stopped. 4 (4a, 4b) prevents solidification of fuel oil in the system. Regarding the storage tank side piping system 9, the operation is continued by operating the transfer pump 8 even when the engine is stopped and bypassing the entire amount from the pressure regulating valve 15 installed in the immediate vicinity of the fuel switching valve 50, so that the entire piping system is kept in a uniform temperature state. Can keep.

  In a diesel engine 3 that neatly uses such high pour point vegetable oil (uses it straight without mixing), the engine is started with a low-viscosity oil such as A heavy oil or BDF (biodiesel fuel) with good combustibility. When the engine is fully warmed up (approx. 50% load), it is switched to vegetable oil to operate, and a system that suppresses the generation of combustion residues due to incomplete combustion is adopted. To facilitate starting, switch to low viscosity oil such as A heavy oil or BDF at a constant load (about 50% load), and completely replace the fuel piping system with low viscosity oil to start the next engine. Prepare.

  In the present embodiment, regarding the oil temperature management in the vegetable oil tank 7, in order to prevent the resin from being formed by promoting the oxidative deterioration due to the long-time heat storage of the fuel or by promoting the polymerization due to overheating, and the pour point of the vegetable oil is different. In order to maintain a viscosity that does not hinder the transfer, a method for appropriately controlling the temperature of the vegetable oil by the heating means 12 controlled based on the detection result of the viscosity measuring means 11 and maintaining the minimum necessary heating is provided. In addition, the transfer pump 8 is always operated to improve heat transfer by the stirring effect of the return oil to the tank 7 and to maintain the temperature in the tank more uniformly.

Concerning vegetable oil discharge from the diesel engine fuel supply circuit 4 (4a, 4b) at the time of an emergency stop of the engine, the drain side switching valves a1, a2 in FIGS. Next, the drain switching valves b1 and b2 are opened, and a high pressure gas cylinder (N ₂ or air) hose (high pressure gas supply path 20) is connected to the fuel oil circulation main pipe end 19 of the engine side system. Connected, the vegetable oil remaining in the diesel engine fuel supply circuit 4 (4a, 4b) on the engine side is discharged with high-pressure gas to prevent the vegetable oil from solidifying in the pipe.

  At this time, if the engine can be turned, an automatic discharge valve (air that communicates with the cylinder of the engine) attached to a cylinder head (not shown) is provided so that air running (turning of the engine with compressed air) can be easily performed. A method of allowing the vegetable oil remaining in the fuel injection pump 18 to be discharged by discharging the vegetable oil to the outside of the cylinder while performing air running with the automatic opening / closing control valve provided at the discharge port open. It was adopted. Moreover, regarding the vegetable oil discharge from the diesel engine fuel supply circuit 4 (4a, 4b) on the auxiliary equipment side, by opening the drain on-off valve provided in the diesel engine fuel supply circuit 4 (4a, 4b) The automatic exhaust valve 37 at the upper part of the fuel circulation tank 1 located at the highest position in the equipment-side fuel oil piping of the diesel engine fuel supply circuit 4 (4a, 4b) is operated as a vacuum breaker valve, and is discharged by the head pressure. .

  Concerning the fuel oil drain from the diesel engine fuel supply circuit 4 (4a, 4b), the fuel oil drain that does not mix with the steam other than the fuel oil drain tank 26 mixed with the steam used for cleaning. The fuel is recovered in the tank 30 and reused as fuel by controlling the liquid level of the drain tank 30 upstream of the fuel circulation tank 1 in the diesel engine fuel supply circulation path 4 (4a, 4b) or directly returning to the fuel circulation tank 1. The system was adopted to facilitate handling and reduce waste.

  Vegetable oil that does not flow at room temperature is generally better in ignitability than heavy oil A, etc., but has a high molecular weight and a high evaporation temperature, so the burn-out period is long, so it burns completely to prevent engine contamination. In order to maintain good engine performance and improve economy, the engine is operated with A heavy oil or BDF or the like, and after it is sufficiently warmed up, it is switched to vegetable oil for operation.

When the engine is stopped, it is switched to heavy oil A or BDF (biodiesel fuel) at a load of about 50%, making it easy to start the next engine without leaving any non-fluid vegetable oil or the like in the fuel oil piping at room temperature. .
In addition, this embodiment includes a fuel oil piping system that can effectively drain vegetable oil before the temperature of the vegetable oil is lowered when the engine is stopped in an emergency while operating with a vegetable oil that is not fluid at normal temperature.

2. Detailed Description of Embodiments (First)
Based on the understanding of the outline of the above-described embodiment, the main configuration and main effects of each part of the embodiment will be generally described with reference to FIGS. 1 and 2.

  The fuel oil supply device for a diesel engine according to the embodiment includes a fuel circulation tank 1 as a fuel tank of about 200 to 400 liters that stores fuel oil supplied to the diesel engine 3 and also functions as a fuel mixer. . The diesel engine fuel supply circuit 4 for supplying fuel oil from the fuel circulation tank 1 to the diesel engine 3 via the supply pump 2 and returning the excess fuel oil to the fuel circulation tank 1 is provided for each fuel injection of the diesel engine 3. A fuel oil circulation main pipe for supplying fuel to the pump 18 is included. The fuel circulation tank 1 is also a part of the configuration of the diesel engine fuel supply circulation path 4. That is, the diesel engine fuel supply circulation path 4 is constituted by a supply path (outward path) 4a and a return path (return path) 4b, and the fuel oil stored in the fuel circulation tank 1 is provided in the supply path 4a and in this. The surplus fuel oil that was supplied to the diesel engine 3 by the supply pump 2 and could not be consumed by the diesel engine 3 can be returned to the fuel circulation tank 1 through the return path 4b.

  A fuel heating means 16 is provided in the supply path 4a of the diesel engine fuel supply circuit 4, and the high pour point vegetable oil is heated to a kinematic viscosity suitable for spraying to the diesel engine fuel supply circuit 4. It can be circulated. Specifically, although the steam line heater is illustrated in the embodiment, an electric line heater, an electric heater provided in a low pour point oil tank, or a steam heater may be used.

  In the diesel engine fuel supply circulation path 4, a static mixer 29 is interposed in a suction side pipe line of the fuel supply pump 2. This installation position is an example, and may be provided, for example, in the discharge side pipe line of the pump outlet. This static mixer 29 is a mixer having no driving part and a rotating part, and mixes and mixes by dividing, converting, and reversing the fluid flowing therethrough by an element fixed in the pipe line. Since the agitation can be further added to the high pour point vegetable oil flowing through the diesel engine fuel supply circuit 4, the viscosity of the high pour point vegetable oil, which is a non-Newtonian fluid whose viscosity is further lowered by the fluidized state, is further reduced. In addition, the viscosity necessary for supplying the diesel engine 3 can be further easily obtained. In addition, fuel oils having different kinematic viscosities are mixed and supplied at the time of switching the supplied fuel oil when the engine is started and stopped, and uniform combustion can be ensured by uniformly mixing the mixed oil. .

  In the supply path 4a of the diesel engine fuel supply circuit 4, there is a viscosity measuring means (viscosity sensor) 56 that measures the viscosity of the circulating high pour point vegetable oil in the vicinity of the inlet side of the fuel injection pump 18 of the diesel engine 3. Is provided. A heating unit 16 is provided in the supply passage 4 a of the diesel engine fuel supply circulation passage 4 on the downstream side of the supply pump 2. A viscosity control means (viscosity controller) 57 is connected to the viscosity measuring means 56. The viscosity control means 57 controls the heating means 16 based on the viscosity data of the high pour point vegetable oil detected by the viscosity measuring means 56, and appropriately heats the high pour point vegetable oil in the supply path 4a to maintain a predetermined viscosity. can do.

  In the return path 4b of the diesel engine fuel supply circuit 4, a cooler 55 controlled by a temperature controller is provided. The cooler 55 manages the kinematic viscosity to be constant by cooling the return oil from the diesel engine 3 whose temperature has been raised, and prevents the bearing of the supply pump 2 and the plunger of the fuel injection pump 18 from sticking.

  Thus, in this embodiment, in order to spray the high pour point vegetable oil supplied to the diesel engine 3 without hindrance, the fuel heating unit 16 includes a viscosity measuring unit (viscosity sensor) 56 and a viscosity control unit (viscosity controller). 57, and cooling of the return oil from the engine that has become unnecessarily high due to compression by the fuel injection pump 18 by a cooler 55 controlled by a temperature regulator, thereby controlling the viscosity of the fuel oil appropriately. Realized to keep the kinematic viscosity of the fuel constant. For this reason, the bearing of the supply pump 2 and the plunger of the fuel injection pump 18 are reliably prevented, and the operation of the diesel engine 3 using the high pour point vegetable oil and the low pour point oil can be performed without any trouble.

  The fuel oil supply apparatus includes a low pour point oil tank 5 that stores low pour point oil as a first tank that supplies fuel to the fuel circulation tank 1. The low pour point oil tank 5 is provided at a high place, and the low pour point oil tank 5 and the fuel circulation tank 1 are connected by a low pour point oil supply path 6. By switching the three-way valve 50 provided in the middle of the low pour point oil supply path 6, the low pour point oil can be supplied to the fuel circulation tank 1 by gravity flow as necessary. The low pour point oil supply passage 6 is provided with a fuel heating means 17 for supplying high temperature low pour point oil exceeding the solidification start temperature of the high pour point vegetable oil to the fuel circulation tank 1. In the embodiment, the fuel heating means 17 is provided in the middle of the circulation pipe 6 a connected to the low pour point oil tank 5, but may be provided inside or outside the low pour point oil tank 5, and the low flow point It may be provided in the spot oil supply path 6.

The fuel oil supply apparatus includes a high pour point vegetable oil tank 7 that stores high pour point vegetable oil that does not flow at room temperature as a second tank that supplies fuel to the fuel circulation tank 1. The high pour point vegetable oil tank 7 and the fuel circulation tank 1 are connected by a high pour point vegetable oil circulation path 9 having a supply path 10. That is, the supply path 10 branched from the branch part 14 of the high pour point vegetable oil circulation path 9 is connected to the other port of the three-way valve 50 to which the low pour point oil supply path 6 is connected to one port, By switching the three-way valve 50, a high pour point vegetable oil and the low pour point oil can be alternatively supplied to the fuel circulation tank 1 as required. Therefore, in this embodiment, the pipe line from the three-way valve 50 to the fuel circulation tank 1 serves as the supply path 10 and the low pour point oil supply path 6, and a flow accumulator (integrated flow rate and instantaneous flow rate FQ and a check valve 59 are provided.
When the three-way valve 50 is not used, the supply passage 10 and the low pour point oil supply passage 6 are independently connected to the fuel circulation tank 1, and an opening / closing valve is provided in each of the supply passages 6 and 10. Alternatively, the fuel circulation tank 1 may be selectively switched between open and closed.

  The high pour point vegetable oil circulation path 9 is a high pour point vegetable oil supply path 9b on the upstream side of the branch section 14, and a high pour point vegetable oil return path 9a on the downstream side of the branch section 14. Two circulation pumps 8 are provided in parallel on the upstream side of the supply path 9 b of the high pour point vegetable oil circulation path 9. By this circulation pump 8, high pour point vegetable oil can be sent out from the high pour point vegetable oil tank 7, and at least a part thereof can be supplied to the fuel circulation tank 1 via the three-way valve 50 and the supply path 10, and the rest. The high pour point vegetable oil can be returned to the high pour point vegetable oil tank 7 by the return path 9a.

  The supply path 9 b of the high pour point vegetable oil circulation path 9 is provided with a viscosity measuring means (viscosity sensor) 11 for measuring the viscosity of the circulating high pour point vegetable oil on the downstream side of the circulation pump 8. The high pour point vegetable oil tank 7 is provided with heating means 12. A viscosity control means (viscosity controller) 70 is connected to the viscosity measuring means 11. The viscosity control means 70 controls the heating means 12 based on the viscosity data of the high pour point vegetable oil detected by the viscosity measuring means 11, and appropriately heats the high pour point vegetable oil in the high pour point vegetable oil tank 7 to obtain a predetermined value. The viscosity can be maintained. Although the heating means 12 is provided in the high pour point vegetable oil tank 7, another circulation path may be provided outside the high pour point vegetable oil tank 7 and provided there. Furthermore, you may provide in the pipe line of the said high pour point vegetable oil circulation path 9, etc. FIG.

  In addition to the heating means 12, all the piping and equipment through which the high pour point vegetable oil flows may be provided with other heating and heat retaining means such as a steam trace or an electric heater so that the high pour point vegetable oil can be heated and kept warm. .

  The return path 9a of the high pour point vegetable oil circulation path 9 is led into the high pour point vegetable oil tank 7, and its end is branched into a plurality of openings. Therefore, the high pour point vegetable oil that has returned to the high pour point vegetable oil tank 7 via the return path 9a effectively agitates the high pour point vegetable oil in the tank by the circulation energy, and the high pour point vegetable oil in the tank. Maintain a uniform temperature.

In this embodiment, the end of the return path 9a is branched in the high pour point vegetable oil tank 7, but may be branched before reaching the high pour point vegetable oil tank 7. Further, the plurality of ends of the return path 9a opened in the high pour point vegetable oil tank 7 are directed with a certain regularity so that the high pour point vegetable oil in the high pour point vegetable oil tank 7 can be effectively flowed. It is preferable to make it.
In this way, since the heat transfer coefficient of the vegetable oil is small, the end of the return path 9a to the high pour point vegetable oil tank 7 is branched and opened to agitate the stored oil in the tank using the energy of the circulating oil. By performing effectively, the temperature of the stored oil in the tank can be maintained uniformly, and the high pour point vegetable oil exhibiting the non-Newtonian fluid characteristic tendency that the viscosity is further lowered by making it into a fluid state can be stored at a lower temperature. .

  A first pressure regulating valve 13 is provided in the return path 4 b of the diesel engine fuel supply circulation path 4. As for the set pressure, for example, the primary side pressure (upstream side nearest) is 0.5 MPa. Further, a second pressure regulating valve 15 is provided on the downstream side of the branching portion 14 of the high pour point vegetable oil circulation path 9 for supplying the high pour point vegetable oil to the fuel circulation tank 1. As for the set pressure, for example, the primary pressure (upstream side nearest) is 0.3 MPa, which is smaller than the set pressure of the first pressure regulating valve 13 of the diesel engine fuel supply circuit 4.

  Therefore, very roughly speaking, the region from the discharge side of the supply pump 2 of the diesel engine fuel supply circuit 4 to the upstream side of the first pressure regulating valve 13 is a high pressure region of about 0.5 MPa, and the high pour point vegetable oil circuit 9 From the discharge side of the circulation pump 8 to the upstream side of the second pressure regulating valve 15, the supply path 10 branched from the high pour point vegetable oil circulation path 9, the fuel circulation tank 1, and the first pressure regulation valve 13 of the diesel engine fuel supply circulation path 4. From the downstream side to the suction side of the supply pump 2 is a low pressure region of about 0.3 MPa. Moreover, since the diesel engine fuel supply circuit 4 is a closed system, the high pour point vegetable oil circulated in the high pour point vegetable oil circuit 9 is supplied to the fuel circulation tank 1 via the supply channel 10, and the diesel engine. The high pour point vegetable oil corresponding to the consumed fuel amount is automatically supplied from the high pour point vegetable oil circulation path 9 to the fuel circulation tank 1.

  According to the configuration described above, the high pour point vegetable oil in the high pour point vegetable oil tank 7 is agitated by circulating the high pour point vegetable oil through the circulation pump 8 and the high pour point vegetable oil circulation path 9, thereby the high pour point. Since the heating means 12 is controlled by the viscosity measuring means 11 while the temperature in the vegetable oil tank 7 is quickly made uniform, it is possible to quickly control the temperature with high thermal efficiency, and any pour point high pour point vegetable oil is used. Even in this case, it is possible to reliably maintain the necessary viscosity while suppressing the oxidative deterioration due to warm storage as much as possible with the minimum necessary heating. Further, when a part of the high pour point vegetable oil that is constantly circulating in the high pour point vegetable oil circulation path 9 is supplied to the fuel circulation tank 1, the circulating energy is converted to the high pour point vegetable oil. Therefore, it is not necessary to provide a separate pump for supply.

  Further, when the fuel oil supplied to the diesel engine 3 is switched from the low pour point oil to the high pour point vegetable oil or when the high pour point vegetable oil is switched to the low pour point oil, the fuel heating means 17 converts the low pour point oil to the high pour point. Since it can be heated to a temperature higher than the solidification start temperature of the vegetable oil and supplied to the fuel circulation tank 1, even if this low pour point oil contacts the high pour point vegetable oil, the high pour point vegetable oil is cooled and solidified. The phenomenon does not occur, and the piping and the fuel circulation tank 1 are not blocked.

Next, the fuel oil supply device of the diesel engine according to the present embodiment relates to the treatment of the fuel oil drain, the fuel oil drain tank 26 mixed with the steam used for cleaning, and the fuel oil not mixed with the steam or the like. The drain tank 30 is provided.
A fuel oil drain main pipe 22 having a downward slope toward the drain tank 26 is connected to the fuel oil drain tank 26 mixed with cleaning steam or the like. Also, each fuel injection valve 24 of the diesel engine 3 is connected to one end portion of a fuel drain branch pipe 25 with a downward gradient that causes the fuel drain discharged from each fuel injection valve to flow down. The other end of the fuel drain branch pipe 25 is connected to a fuel oil drain main pipe 22 via an on-off valve 23, and a high pressure gas supply connection port 27 or a high pressure gas supply path 28 is connected to the end of the fuel oil drain main pipe 22. Is provided.

  The drain branch pipe 25 and the fuel oil drain main pipe 22 are provided with heating means such as a steam trace and a tape heater, and during the purge cleaning with the high pressure gas, the high pressure gas is discharged before the temperature of the high pour point vegetable oil is lowered. Can be discharged reliably.

The fuel oil drain tank 30 and the fuel circulation tank 1 that are free of vapor and the like are connected by a drain path 32 that is inclined downward from the fuel circulation tank 1 toward the fuel oil drain tank 30. In addition, the supply path 4 a and the return path 4 b of the diesel engine fuel supply circulation path 4 are connected to the fuel oil drain tank 30 by a plurality of drain paths 33 with a downward gradient reaching the fuel oil drain tank 30. The fuel oil drain tank 30 is configured to communicate with the atmosphere via the intake / exhaust pipe 71, whereas the diesel engine fuel supply circulation path 4 including the fuel circulation tank 1 is a closed system. The fuel oil drain tank 30 is an open system including drain paths 32 and 33.
The fuel oil drain tank 30 is provided with a heating means 31 and a liquid level controller 75. The fuel oil drain tank 30 is connected to the fuel circulation tank 1 by a return path 36 via a pump 34, a check valve 35, etc., and the high pour point vegetable oil collected as drain is sent to the fuel circulation tank 1. can do. When the recovered fuel oil drain is returned, the check valve 59 provided between the flow accumulator FQ and the fuel circulation tank 1 prevents the fuel drain return oil or the like from flowing into the supply paths 6 and 10. To prevent backflow.

  Further, drain switching valves a1 and a2 are respectively provided in the supply path 4a and the return path 4b of the diesel engine fuel supply circulation path, and the drain paths 33 and 33 connected to the supply path 4a and the return path 4b, respectively. Are provided with drain switching valves b1 and b2, respectively. The fuel oil circulation main pipe end 19 of the diesel engine fuel supply circulation path 4 is provided with a high-pressure gas supply connection port 21, and the high-pressure gas supply connection port 21 is connected via the high-pressure gas supply path 20. A nitrogen or air cylinder 51 as a high-pressure gas source for purging can be connected.

  In this embodiment, the drain switching valve is composed of a combination of valves such as switching valves a1 and b1 and switching valves a2 and b2. However, the function of the combination of switching valves a1 and b1 is a single valve. You may provide the three way valve which exhibits in the supply path 4a and the return path 4b of the said diesel engine fuel supply circuit 4, respectively. Note that air, nitrogen gas, or the like can be used as the high-pressure gas.

  Therefore, when purging the high pour point vegetable oil in the pipe, the drain switching valves a1 and a2 are closed, the path to the fuel circulation tank 1 is shut off, the drain switching valves b1 and b2 are opened, and the fuel oil circulation main pipe If the high pressure gas is supplied from the end portion 19, the high pour point vegetable oil can be guided to the drain passage 33 by the pressure of the high pressure gas and can be discharged to the fuel oil drain tank 30 as drain. In this way, the vegetable oil remaining in the engine fuel oil piping system is forcibly discharged, and it is possible to prevent the vegetable oil from coagulating inside the piping due to a decrease in temperature after the engine is stopped.

  In the present embodiment, the drain passages 32 and 33 are connected to the diesel engine fuel supply circulation passage 4. In addition to the drain passage branched from the diesel engine fuel supply circulation passage 4 in this way, the diesel engine fuel supply passage is provided. There may be a drain path from the equipment intervened in the circulation path 4. In that case, a valve that separates from the diesel engine fuel supply circulation path 4 and the fuel circulation tank 1 is provided at the base of each drain path.

  It is preferable that steam drains or electric heaters are provided along all the drain paths 32 and 33 so as to be kept warm.

According to the configuration described above, the drain of the fuel oil from the fuel circulation tank 1 side and the drain of the high pour point vegetable oil from the diesel engine fuel supply circulation path 4 side both descend to the fuel oil drain tank 30. The oil is collected in the fuel oil drain tank 30 through the drain passages 32 and 33 with a gradient. The collected high pour point vegetable oil drain is maintained by the heating means 31 at a predetermined temperature that always maintains fluidity. When the liquid level controller 75 detects that the accumulated drain in the fuel oil drain tank 30 has reached a predetermined level, the pump 34 is activated and the return path 36 is connected to the fuel circulation tank 1 via the check valve 35. The drain is oiled and used again. When the liquid level controller 75 detects that the drain in the fuel oil drain tank 30 has been transported and has reached a predetermined low level, the pump 34 is stopped. The check valve 35 of the return path 36 prevents the fuel of the engine side / auxiliary equipment side fuel oil piping system from flowing back to the drain tank 30 during normal operation so that the fuel on the equipment side of the diesel engine fuel supply circulation paths 4a, 4b. Drain oil is returned to the fuel circulation tank 1 in the piping system and can be used as fuel. Further, the check valve 59 provided between the quantity integrator FQ of the supply passages 6 and 10 and the fuel circulation tank 1 does not prevent drain oil or the like from flowing into the supply passages 6 and 10 when the pump 34 is started. To prevent backflow.
The set pressure of the return path 36 for feeding the drain oil from the fuel oil drain tank 30 to the fuel circulation tank 1 through the pump 34 and the check valve 35 is provided in the return path 4b of the diesel engine fuel supply circulation path 4. The pressure of the new high pour point vegetable oil supplied to the fuel circulation tank 1 at a pressure lower than the primary side set pressure (near the upstream side) of the first pressure regulating valve 13, that is, the high pour point vegetable oil circulation path 9. The pressure is set to be equal to or higher than the primary set pressure of the second pressure regulating valve 15 on the downstream side of the branching section 14 (upstream side nearest) and the supply pressure of the low pour point oil from the low pour point oil tank 5. Preferably, the return pressure of the drain is such that the first pressure regulating valve 13 provided on the return path 4b of the diesel engine fuel supply circuit 4 is set on the primary side (immediately upstream) and the branch part 14 of the high pour point vegetable oil circuit 9. The pressure is set to an intermediate pressure with the primary set pressure (immediately upstream) of the second pressure regulating valve 15 on the downstream side.

  An automatic exhaust valve 37 that discharges gas in the tank is attached to the head of the fuel circulation tank 1, and the discharge side of the automatic exhaust valve 37 exhausts to a drain path 32 that reaches the fuel oil drain tank 30. They are connected via a path 38.

Therefore, the gas that has flowed out of the fuel circulation tank 1 from the automatic exhaust valve 37 is released to the atmosphere through the fuel oil drain tank 30, so that the fuel oil is not scattered into the atmosphere. Further, in order to stop or maintain the diesel engine 3, the fuel oil remaining in the tank, equipment, passage or pipe of the fuel oil supply device of the diesel engine 3 is discharged from the drain passages 32 and 33 to the fuel oil drain tank 30. In this case, the automatic exhaust valve 37 operates as a vacuum break valve. That is, since air flows into the closed system fuel circulation tank 1 through the fuel oil drain tank 30 and the automatic exhaust valve 37, the fuel oil can be smoothly discharged into the fuel oil drain tank 30.
The automatic exhaust valve 37 is also referred to as an automatic air vent valve, and is a valve that automatically exhausts a gas body accumulated during operation in a liquid system under an operating pressure, and is defined by JIS. Most of them are float type, for example, type VS1C manufactured by TLV Co., Ltd. can be preferably used.

  Although not mentioned in the above description, the present fuel oil supply apparatus includes a steam boiler 80, and when the heating means 12, 16, 17, 31 use steam as a heat source, these are used. In addition to being able to supply steam with the steam boiler 80, steam can also be supplied to each device that requires steam in the fuel oil supply apparatus as necessary. The fuel oil supply apparatus has an emergency engine and a generator 81. In addition to supplying necessary electricity to the steam boiler 80, each fuel oil supply apparatus also has various devices that require electricity. Electricity can be supplied as needed.

Although not mentioned in the above description, the reference numerals of the figures shown in FIGS. 1 and 2 have the following meanings.
PI ... Direct indicating pressure gauge PE ... Pressure detection element PC ... Pressure adjustment PA ... Pressure alarm TE ... Temperature detection element LC ... Level adjustment LA ... Level alarm FQ ... Flow accumulator FV ... Fuel injection valve

3. Detailed Description of Embodiment (Second)
Embodiments of the present invention will be described below in more detail with reference to FIGS. 1 to 6, but items corresponding to characteristic configurations such as configurations described in specific claims are appropriately set. explain.
1 and 2 from the vegetable oil storage tank 7 to the three-way valve 50 for switching from low-viscosity fuel oil such as A heavy oil or BDF (biodiesel fuel) to vegetable oil at room temperature. The storage tank side fuel pipe 9b (9) is called, and this pipe system is provided with a return pipe 9a (9) from the immediate vicinity of the three-way valve 50 to the vegetable oil storage tank 7 in which the pressure regulating valve 15 is installed. The vegetable oil storage tank 7 is heated with steam trace, high-temperature water, or a heater 12, and the circulation pump 8 installed in the immediate vicinity of the vegetable oil storage tank 7 is operated. Based on the detection result of the viscosity sensor (viscosity measuring means 11). The vegetable oil storage tank is controlled by heating with the heater 12 controlled by the viscosity controller 70 as viscosity control means. 7 side of the fuel piping 9 to circulate the controlled plant oils constant viscosity to prevent coagulation of vegetable oils by local cold reduction in vegetable oil storage tank fuel pipe 9 system.

In the diesel engine fuel supply circulation paths 4a and 4b in FIG. 1 and FIG. 2, the diesel engine pipes to the drain switching valves a1 and a2 and the drain switching valves b1 and b2 are called engine-side fuel oil pipes. The switching valves b1 and b2 are installed at the lowest position of the entire piping system so that the vegetable oil can be easily discharged from the engine side fuel oil piping and the equipment side fuel oil piping defined below with the head pressure. Further, a compressed gas cylinder (N ₂ gas or the like) having a pressure reducing valve is disposed at the fuel oil circulation main pipe end 19 in the diesel engine 3 for the purpose of effectively discharging the vegetable oil remaining in the engine when the diesel engine 3 is urgently stopped. ) Is installed.

  Viscosity measuring means for controlling the fuel heating means 16 so that the kinematic viscosity of the vegetable oil supplied to the engine becomes a value suitable for spraying in the piping system of the diesel engine fuel supply circulation paths 4a and 4b in FIGS. Viscosity sensor) 56 and viscosity control means (viscosity controller) 57 are installed to appropriately manage the viscosity of the fuel oil. Also, when switching from vegetable oil to low viscosity oil such as A heavy oil or BDF, the return oil from the engine that has become unnecessarily hot due to compression by the fuel injection pump 18 is cooled by the cooler 55, and mixed oil By controlling the engine inlet temperature, the kinematic viscosity is managed to prevent the bearing of the fuel supply pump 2 and the plunger of the fuel injection pump 18 from sticking.

  Also, when switching from low pour point oil such as A heavy oil or BDF to high vegetable oil that is high pour point oil when loading after engine startup, and when switching from vegetable oil to A heavy oil or BDF, etc. when reducing engine stop load In order to prevent the vegetable oil from solidifying due to a decrease in the temperature of the mixed oil in the fuel circulation tank 1, the fuel oil is switched after the A heavy oil is heated to a temperature equal to or higher than the solidification start temperature of the vegetable oil in advance. In particular, when the fuel is switched when the load is lowered before the engine is stopped, if the temperature of the heavy fuel oil A or BDF is increased too much, the kinematic viscosity is excessively decreased, and the bearing of the fuel supply pump 2 and the plunger of the fuel injection pump 18 are fixed. There is concern and it is necessary to manage the temperature rise of A heavy oil or BDF so as not to exceed the upper limit.

  Further, as shown in FIGS. 3A and 3B, the diesel engine fuel supply circulation paths 4a and 4b are in operation with respect to equipment such as filters, flow meters, and fuel supply pumps in the equipment side fuel oil piping system. A bypass pipe 60 is provided to enable maintenance. In order to facilitate the discharge of the remaining plants in this portion when the fuel is discharged using the head pressure, the bypass pipe 60 is connected to each device as shown in FIG. As shown in FIG. 4B, the vacuum valve is broken by the vent valve 58 or the vacuum breaker valve 37 of the bypass pipe.

  The various fuel drain pipes 32 and 33 shown in FIGS. 1 and 2 are always piped so as to have a downward slope on the discharge side in order to facilitate discharge at the head pressure. In addition, the drain tank 30 and various drain pipes are heated and insulated with steam trace, high temperature water, heating wire, etc. so that the low temperature part is not partially made, and the drain transfer is facilitated and the drain discharge failure and the drain tank Prevent drain spills.

  In this embodiment, the fuel oil piping system includes two storage tank side fuel oil pipes 9 from the vegetable oil storage tank 7 to the three-way switching valve 50 and two diesel engine fuel supply circulation paths 4a and 4b that are engine / equipment side fuel oil pipes. The system is separated into systems, and no fuel oil stays in each piping system, so that the entire fuel oil piping system is kept at a uniform temperature to avoid the occurrence of local solidification of vegetable oil.

  Regarding the vegetable oil storage tank side piping system 9, two identical capacity pumps are installed in parallel as the transfer pump 8 and are always operated, and even in the case of an emergency, a sufficient discharge amount is sufficient to satisfy the function as an emergency reserve. Let Further, as shown in FIG. 6, since the heat transfer coefficient of the vegetable oil is small, the return fuel pipe 9a to the tank 7 is branched into a plurality of pipes and is arranged so as to be ejected from the bottom of the tank to the center of the tank. It is characterized in that the temperature of the stored oil in the tank is kept uniform by effectively agitating the stored oil in the tank using the energy of the oil.

  At the time of an emergency engine stop, in response to the fuel oil treatment, the fuel switching valve 50 of the storage tank side fuel piping system 9 is switched to the A heavy oil side to make the vegetable oil side a closed circuit, and based on the outputs of the transfer pump 8 and the viscosity measuring means 11 The operation of the viscosity controller 70 for controlling the heating means 12 is continued to obtain an appropriate heat retaining state.

◎ Storage tank side fuel oil piping etc.
Between the outdoor installed vegetable oil storage tank 7 having heating means 12 such as steam or hot water and the three-way valve 50 for switching from low-viscosity fuel oil to vegetable oil such as A heavy oil or BDF (biodiesel fuel). For the vegetable oil storage tank side fuel oil pipe 9, a return pipe 9a from the position close to the switching three-way valve 50 to the vegetable oil storage tank 7 is provided, and the piping line is heated and insulated by a pressure regulating valve 15 and steam trace or hot water. Switching from the vegetable oil storage tank 7 at a constant pressure by operating the fuel circulation pump 8 installed in the immediate vicinity of the vegetable oil storage tank 7 with the three-way valve 50 closed on the plant piping side closed during the preparatory period before starting the engine Vegetable oil can be circulated through the piping between the three-way valves 50, and the vegetable oil storage unit It is characterized in that the piping system is not part of local temperature drop keeping the whole line of click-side fuel pipe 9 at a uniform temperature.

Since the transfer piping portion of the fuel oil system 9 on the storage tank 7 side tends to cause partial solidification of the vegetable oil due to local cooling when the outside air temperature decreases, such as in winter, the transfer pump 8 A pressure regulating valve 15 having a capacity capable of returning the entire discharge amount is provided so that the vegetable oil circulates through the entire fuel transfer pipe even when the engine 3 is stopped, so that the entire fuel oil system on the storage tank 7 side can always be maintained at a constant required temperature. To.
The set pressure of the pressure regulating valve 15 is lower than the set pressure of the pressure regulating valve 13 of the diesel engine fuel supply circulation paths 4a and 4b so as not to interfere with the pressure regulation valve 13 of the diesel engine fuel supply circulation paths 4a and 4b. It is characterized by being set to.

  According to the embodiment, as shown in FIGS. 1 and 2, the fuel heating means 16 is provided in the diesel engine fuel supply circulation path 4, and the fuel heating means 17 is provided in the low pour point oil supply path 6 to flow at normal temperature. The low-pour point oil having a high temperature exceeding the solidification start temperature of the non-preferable high-pour point vegetable oil can be supplied to the fuel circulation tank 1. The fuel heating means 16 of the diesel engine fuel supply circuit 4 is controlled by the viscosity controller 57 based on the kinematic viscosity measured by the viscosity measuring means 56 (viscosity sensor or viscometer).

  For this reason, when switching the supply fuel oil of the diesel engine 3 from the low pour point oil to the high pour point vegetable oil, or when switching from the high pour point vegetable oil to the low pour point oil, the low pour point oil is used. Since it can be supplied to the fuel circulation tank 1 at a temperature higher than the solidification start temperature of the high pour point vegetable oil, even if the low pour point oil contacts the high pour point vegetable oil, the high pour point vegetable oil is cooled and solidified. Therefore, the pipe and the fuel circulation tank 1 are not blocked.

The operation at the time of switching the fuel oil as described above will be described.
When starting the engine, start with low pour point oil (A heavy oil), increase the load to 50% load, and in that state until the A heavy oil in the diesel engine fuel supply circuit 4 rises from room temperature to 52 ° C to 57 ° C Maintain 50% load (warm up, palm stearin starts to solidify at about 50 ° C). By this operation, the fuel circulation tank is filled with A heavy oil or BDF of 52 ° C. to 57 ° C. through the low pour point oil supply passage 6.

  Then, switch to high pour point vegetable oil. Fuel oil is sprayed by the fuel heating means 16 of the diesel engine fuel supply circuit 4 by switching the fuel switching valve 50 to the high pour point vegetable oil (palm stearin) side while maintaining the 50% load operation. The fuel oil is gradually switched while being heated so as to have a kinematic viscosity suitable for. When the diesel engine fuel supply temperature reaches 77 ° C. to 82 ° C., the load is increased to 100% load (operation with palm stearin).

When the engine is stopped, the engine load is reduced to 50% with high pour point vegetable oil (palm stearin) fuel. Thereafter, the fuel switching valve 50 is switched to the A heavy oil side, and the fuel oil is gradually switched by operating with the A heavy oil heated to 52 ° C. to 57 ° C. instead of the high pour point vegetable oil (palm stearin).
At the beginning of fuel switching, the oil in the diesel engine fuel supply circuit 4 is heated by the temperature control by the viscometer and the kinematic viscosity becomes constant. However, when the amount of heavy fuel oil A increases, the viscosity decreases. As shown in FIGS. 1 and 2, when the kinematic viscosity measured by the viscosity measuring means 56 (viscosity sensor or viscometer) reaches the value of A heavy oil in the diesel engine fuel supply circuit 4, Reduce the load and stop the engine as if it was completely replaced with A heavy oil. The inside of the diesel engine fuel supply circuit 4 is filled with heavy fuel oil A and reaches room temperature, and preparation for the next engine start is completed.

<Explanation of parts related to fuel oil drain system in particular>
Concerning the treatment of fuel oil drain, it is separated into a drain piping system that requires cleaning with steam or the like, and other drain systems, and separate drain tanks 26 and 30 are installed. In connection with the control, the transfer pump 34 is activated when it reaches a certain level under the control of the liquid level controller 75 of the drain tank 30, and a check valve 35 is provided in the transfer pump line. Drain oil is returned to the position immediately upstream of the fuel circulation tank 1 in the equipment side fuel piping system of the diesel engine fuel supply circulation paths 4a and 4b so that the fuel in the side / auxiliary equipment side fuel oil piping system does not flow backward. Make it available.
When returning the drain oil, the check valve 59 provided between the quantity integrator FQ of the supply passages 6 and 10 and the fuel circulation tank 1 causes the fuel oil drain or the like to be supplied to the supply passage 6 when the transfer pump 34 is activated. Thus, backflow is prevented so that it does not flow into 10.
Therefore, the return pressure of the drain is lower than the primary set pressure (immediately upstream) of the first pressure regulating valve 13 provided in the return path 4b of the diesel engine fuel supply circulation path 4, and the fuel circulation tank 1 Pressure of the new high pour point vegetable oil supplied to the pipe, that is, the primary set pressure (closest to the upstream side) of the second pressure regulating valve 15 on the downstream side of the branch portion 14 of the high pour point vegetable oil circulation path 9, and the low pour point oil Set above the supply pressure of the low pour point oil from the tank 5. Preferably, the return pressure of the drain is the first pressure regulating valve 13 set pressure provided in the return path 4b of the diesel engine fuel supply circuit 4 and the second pressure regulating valve on the downstream side of the branch portion 14 of the high pour point vegetable oil circuit 9. It is recommended to return oil at an intermediate pressure of 15 set pressures.

◎ About discharge of residual vegetable oil in equipment side fuel oil piping.
Various devices installed between the three-way valve 50 for switching from fuel oil having a low viscosity at room temperature, such as A heavy oil and BDF, to vegetable oil that solidifies at room temperature, and the drain switching valves b1 and b2 are 2 It is placed at a higher position than the drain switching valves b1 and b2 by installing it at a high place such as on the floor, etc., the drain switching valves a1 and a2 in FIGS. 1 and 2 are opened, and the drain switching valves b1 and b2 are opened. By doing this, the vegetable oil remaining in the device can be easily discharged with a sufficient head pressure.

When the vegetable oil is discharged, an automatic exhaust valve 37 is provided above the fuel circulation tank 1 at the highest position in the equipment-side fuel oil piping of the diesel engine fuel supply circulation paths 4a and 4b so that the vegetable oil can be easily discharged by the head pressure. (With the function of a vacuum breaker valve), the three-way valve 50 is opened on the low pour point oil side, the main valve 61 of the low pour point oil tank 5 is closed, and the drain switching valves b1 and b2 are opened. In this state, the drain switching valves a1 and a2 are opened and the pressure in the fuel oil piping is released, so that the automatic exhaust valve 37 (vacuum break valve) is opened and the vegetable oil remaining in each device can be easily discharged. It is characterized by that.
In the case of fuel oil that does not flow at room temperature, a heating means is required.

◎ Discharge of residual vegetable oil in the bypass pipe 60 for maintenance.
As shown in FIG. 3, with respect to the maintenance bypass piping 60 for various devices in the diesel engine fuel supply circulation paths 4a and 4b, various devices are used as in the example shown for comparison in FIGS. 3 (c) and 3 (d). In order to enable the residual vegetable oil in the bypass pipe 60 to be discharged by the head pressure, rather than being mounted on the same plane as the pipe, as shown in FIGS. 3 (a) and 3 (b), the elevation angle α In addition to the shutoff valve, a vacuum breaker valve (vent valve) is attached to the bypass pipe 60, or a vacuum breaker valve is mounted here as a three-way shutoff valve. It is also possible to replace the exhaust valve 37 (vacuum break valve).

◎ About drain tanks and drain piping.
For all the drain pipes 32 and 33 from which the vegetable oil is discharged and the return pipe 36 from the drain tank 30 to the fuel circulation tank 1, steam trace and hot water trace for the purpose of preventing the solidification of the vegetable oil in the respective pipes. Further, heating and heat insulation and heat insulation such as a heating wire trace are performed, and the drain pipes 32 and 33 are characterized in that piping is performed so that the discharge side has a downward slope so as to facilitate discharge at the head pressure.
All of the above drain circuits are steam traced.

<Particularly explanation of parts related to purge cleaning of fuel supply circuit>
As shown in FIGS. 1, 2, and 4, with respect to the engine side system of the diesel engine fuel supply circulation paths 4a and 4b, the drain switching valves a1 and a2 are closed and disconnected from the auxiliary equipment side system, and then the drain switching valve. Let b1 and b2 be open. Thereafter, a high-pressure cylinder 51 (N ₂ or air) is connected to the fuel oil circulation main pipe end 19 via a high-pressure gas supply path 20, and engine fuel is supplied by supplying high-pressure gas from the fuel oil circulation main pipe end 19 into the pipe. The vegetable oil remaining in the oil piping system can be forcibly discharged to prevent the vegetable oil from coagulating inside the piping due to a temperature drop.

◎ Connection of engine side fuel oil mains.
A fuel inlet / outlet main pipe for supplying fuel to each fuel injection pump of a normal fuel heating type engine has a structure in which the end portion is a bag path and fuel oil is retained. In this method, since the heated fuel oil stays without being replaced, heat is transferred only by heat conduction, so a local temperature drop is likely to occur at that part, and it solidifies at room temperature. If vegetable oil is used, it may cause clogging with fuel oil. For this reason, as shown in FIG. 4, the fuel oil is circulated by connecting the ends of the fuel oil inlet / outlet main pipes.

◎ About discharge of residual vegetable oil from engine side fuel oil piping.
When the engine has stopped due to a serious failure, regarding the drainage of the vegetable oil in the engine-side fuel oil piping, the drain switching valves a1, a2 are closed, and the drain switching valve b1, attached at the lowest position of the engine-side fuel oil piping. By opening b2 and opening the high-pressure cylinder 51 (N ₂ or the like) installed at the fuel oil main pipe end 19 of the engine, the system is configured to discharge the vegetable oil in the engine-side fuel oil pipe with compressed gas.

◎ About discharge of residual vegetable oil in the fuel injection pump 18.
When it is determined that turning of the engine 3 is possible even after a serious failure stop, the automatic opening / closing discharge valve attached to the cylinder head is operated to turn the engine 3 while releasing the compressed air in the combustion chamber. By discharging the vegetable oil in the fuel oil pipe, the vegetable oil remaining in the fuel injection pump 18 can be discharged.

  When performing such an operation, if the engine 3 can be turned by compressed air, a cell motor, an air motor, etc., the fuel handle is stopped so that the residual vegetable oil in the plunger of the fuel injection pump 18 can be discharged simultaneously. By setting the position, the fuel injection pump 18 is returned to the non-injection position, and the remaining vegetable oil in the fuel injection pump 18 is purged with high-pressure gas while turning the engine 3.

  At that time, an automatic opening / closing discharge valve attached to a component constituting the combustion chamber, for example, the opening of the cylinder head, is opened so that the turning of the engine 3 can be performed quickly, and the piston is moved in a decompressed state in the combustion chamber. When the engine is turned in this way, the plunger of the fuel injection pump 18 is moved up and down at the non-injection position, and the fuel intake port and the spill port of the barrel of the fuel injection pump 18 are inevitably moved at the timing when the plunger is lowered. The supply path 4a (forward path) side and the return path 4b (return path) side of the diesel engine fuel supply circulation path 4 of the fuel injection pump 18 are instantaneously and completely communicated with each other. The remaining high pour point vegetable oil (vegetable oil) in the plunger of the fuel injection pump 18 can be easily discharged by purging.

  The control rack of the fuel injection pump 18 is connected to the governor and the fuel handle via a fuel link. The control rack meshes with the control pinion, and there is a notch in the lower part of the sleeve integrated with the control pinion, and a hook in the lower part of the plunger is fitted in the notch. Therefore, the plunger can be rotated inside the barrel by moving the fuel link, and the effective stroke changes depending on the phase of the notch in the plunger head and the fuel oil intake port provided in the barrel. .

  When purging the residual oil in the plunger, set the fuel handle to the stop position, make the effective stroke of the plunger zero, and move the plunger up and down by turning the engine by air running etc. When the fuel injection pump is in the vicinity of the lowest point of the plunger, the intake port and spill port of the barrel are directly connected, and the residual oil can be easily purged.

  As described above, in the present embodiment, the automatic open / close discharge valve that brings the combustion chamber into the communication state and the decompression state in the combustion chamber when the purge cleaning with the high-pressure gas from the fuel oil circulation main pipe end 19 is performed is performed in the diesel engine. Since the components constituting each combustion chamber (cylinder) of the engine 3 were provided, the following effects were obtained. That is, without the automatic opening / closing discharge valve, when the engine is turned to operate the plunger of the fuel injection pump, the compression process is performed in the cylinder, and the turning torque increases. Become. Instead of such a method, in the present embodiment, the automatic open / close discharge valve causes the combustion chambers of the diesel engine to communicate with the external atmosphere so that the combustion chamber is in a decompressed state, and compressed air, a cell motor, an air motor, etc. It was decided to turn. According to such a method, the plunger of the fuel injection pump 18 can be operated very easily during purge cleaning with the high-pressure gas from the fuel oil circulation main pipe end 19. By this operation of the plunger, the supply path 4a (forward path) side and the return path 4b (return path) side of the diesel engine fuel supply circulation path 4 of the fuel pump are instantaneously directly connected. By purging, the remaining high pour point vegetable oil (vegetable oil) in the plunger of the fuel injection pump 18 can be purge-cleaned simultaneously and easily.

  Here, “decompression” means an operation for reducing the cylinder compression force, such as a decompressor, a decompression device, or the like. Decompression means that the pressure of the hydraulic cylinder is gently released by a press or the like to reduce the impact of the circuit causing damage to the machine. There are two types of diesel engines: a compressed air starting diesel engine that starts by cranking with compressed air and a diesel engine starting with a cell motor or the like (cell motor, air motor). .

<Explanation of the parts related to the drain system of the fuel injection valve>
The drain of the fuel injection valve 24 refers to the sliding between the needle valve of the fuel injection valve and the main body (a valve box or casing in which a nozzle that is a fuel injection pore is formed and slidably accommodates the needle valve). A fuel return oil passage that leaks fuel from the surface or a fuel flow oil that leaks from a screwed portion such as an injection pipe, and guides the leaked fuel from the sliding surface of the needle valve and the main body as in the embodiment shown in FIG. May be connected to the fuel drain branch 25.

  When purging with high-pressure gas from the high-pressure gas supply connection port 27 or the high-pressure gas supply path 28 provided at the end of the fuel oil drain main pipe 22 due to an emergency stop or the like during operation, the fuel drain branch pipe 25 is provided. After the on-off valve 23 is closed, purge cleaning with high pressure gas is performed from the end of the fuel oil drain main pipe 22. The fuel drain branch pipe 25 is in the vicinity of the diesel engine 3 and is not blocked by the drain being cooled by the heat of the engine. This is also a fuel oil piping system that can effectively drain vegetable oil before the temperature of the high pour point vegetable oil is lowered.

  In the above drain circuit, an electric heater is provided in the vicinity of the diesel engine 3, and all other drain circuits and fuel supply circuits are subjected to steam tracing.

  In a diesel engine that starts a cell motor or the like (cell motor, air motor), an air tank that can supply compressed air of a predetermined air pressure is provided for each cylinder as air supply means having a structure similar to that of a start valve of a compressed air start engine. The engine may be provided with an air supply valve that supplies air sent from the air tank to each cylinder, and a pilot air valve (starting air distribution valve) that sends control air to each air supply valve. The pilot air valve opening / closing driving method can be selected from any means such as hydraulic pressure, pneumatic pressure, push rod, and the like.

Regarding Claim 1 or 2 4b ... Return path of diesel engine fuel supply circuit 13 ... First pressure regulating valve 30 ... Fuel oil drain tank 31 ... Heating means 32 ... Drain path 33 ... Drain path 34 ... Pump 35 ... Check valve 36 ... return path

Regarding Claim 3 37 ... Automatic exhaust valve 38 ... Exhaust passage

Regarding Claim 4 29... Static mixer

About the agreement except the above about embodiment 1 ... Fuel circulation tank 2 ... Supply pump 3 ... Diesel engine 4, 4a, 4b ... Diesel engine fuel supply circulation path 5 ... Low pour point oil tank 6 ... Low pour point oil supply path 7 ... High pour point vegetable oil tank 8 ... circulation pump 9 ... high pour point vegetable oil circulation path 9a ... return path to high pour point vegetable oil tank 7 in high pour point vegetable oil circulation path 10 ... supply path of high pour point vegetable oil circulation path 11 ... Viscosity measuring means 12 ... heating means 14 ... branch part of high pour point vegetable oil circulation path 15 ... second pressure regulating valve 16 ... fuel heating means in diesel engine fuel supply circulation path 17 ... fuel heating in low pour point oil supply path 6 Means 19 ... End of fuel oil circulation main pipe of diesel engine 20 ... High pressure gas supply path 21 ... High pressure gas supply connection port 22 ... Fuel oil drain main pipe 23 ... Open / close valve 24 ... Fuel injection valve 25 ... Fuel Drain branch pipe 26 ... drain tank 27 ... high-pressure gas supply connection port 28 ... high-pressure gas supply channel 70 ... viscosity control means a1, b1, a2, b2 ... drain switching valve

Claims (4)

A diesel engine fuel supply circuit for supplying high-pour point vegetable oil that is not fluid at normal temperature from a fuel circulation tank to a fuel injection pump of a diesel engine through a supply pump and returning surplus high-pour point vegetable oil to the fuel circulation tank; ,
A fuel oil drain tank having heating means and communicating with the atmosphere; a drain path with a downward slope extending from the fuel circulation tank to the fuel oil drain tank;
A drain path with a downward gradient from the diesel engine fuel supply circuit to the fuel oil drain tank;
A return path for feeding high pour point vegetable oil as drain from the fuel oil drain tank to the fuel circulation tank via a pump and a check valve;
A fuel oil supply device for a diesel engine, comprising:   A set pressure for a return path for feeding high-pour point vegetable oil, which is drainage, from the fuel oil drain tank to the fuel circulation tank via a pump and a check valve is provided on the return path of the diesel engine fuel supply circulation path. The pressure lower than the primary side set pressure of the first pressure regulating valve, and more than the supply pressure of new high pour point vegetable oil and low pour point oil supplied to the fuel circulation tank. The fuel oil supply apparatus of the diesel engine as described.   The fuel oil supply device for a diesel engine according to claim 1 or 2, further comprising an exhaust passage from the head of the fuel circulation tank to the fuel oil drain tank via an automatic exhaust valve.   The diesel engine fuel supply circuit according to any one of claims 1 to 3, wherein a static mixer is interposed in the diesel engine fuel supply circuit.

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