GB2316739A

GB2316739A - Heating transported substances

Info

Publication number: GB2316739A
Application number: GB9618304A
Authority: GB
Inventors: Abdelbaki Hogga
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-09-02
Filing date: 1996-09-02
Publication date: 1998-03-04
Also published as: GB9618304D0

Abstract

A transportation system for substances in containers is proposed which is particularly useful for the transport of substances which have their melting point in the range of environmental temperatures. As these substances may arrive at their destination in a solid condition the exhaust gases of the transport truck are used to keep the transported substance at an elevated temperature level. In order to achieve this, the exhaust pipe (6) of the truck is connected to a pipe system (20) which connects the exhaust to a heat exchanger (9, 18, Fig.4) which permits the exhaust gases to flow through the heat exchanger and transfer a share of their heat energy to the transported substance. The exhaust gasses leave the heat exchanger through evacuation openings (12a, 12b, figure 3). The container (8, figure 4) preferably comprises a parallelepipedical outer housing (19) and a cylindrical inner housing (10).

Description

TRANSPORTATION SYSTEM FOR SUBSTANCES HAVING A MELTING POINT SIMILAR TO THE TEMPERATURE OF THE ENVIRONMENT Background art: The present invention relates to a transportation system for the transport of substances having their melting point essentially similar to the temperature of the environment during transportation, including a container for the substance to be transported, said container including a heat exchange means for the transfer of external heat to the substance within the container, said container being supported by a truck such as e.g. a trailer-truck.

A variety of substances having their melting point in the range of environmental temperatures are traditionally transported in containers for liquids which are typically transported by trailers such as illustrated in Fig. 1, whereby the substance is poored into the containers in liquid condition, transported to their destination and finally removed from the containers either by pumping by means of a hose which is introduced through the filling opening or by gravitational flow through an evacuation opening situated a the lowest point of the container.

Both of these discharge operations require that the substance be kept in liquid condition, either by reheating an eventually solidified substance, e.g. when the temperature at the destination is lower than the melting point of the substance, or by constantly maintaining the temperature above the melting point.

The reheating of a solidified substance takes considerable time regarding the large volume of the contents of the container, whereas the continuous maintenance of the substance above its melting point during long transportation can become quite expensive in conventional systems which apply a heating means such as an oil burner which is integrated in the container.

The present invention has the objective to propose a transportation system which is capable of continuously maintaining the temperature of the transported substance above its melting point, without causing substantial cost, and which, in addition may be retrofitted into conventional transportation systems using a heating gas for the transfer of heat into the transported substance.

Summary of the invention: According to the invention, this objective is attained in a transportation system according to the preamble of claim 1, which is characterized in that it comprises a connection means from the exhaust of the truck to entry openings of the heat exchange means of the container, the warm exhaust gases of said truck being led into said heat exchange means through said entry openings and leaving said heat exchange means through evacuation openings.

Thus, by using the warm exhaust gases of the engine of the transportation truck, the transported substance is maintained continuously at an elevated temperature without any additional cost of heating fuel or electricity. All that is needed is a modest investment for the connection means between the exhaust and the heat exchanger.

According to a possible embodiment of the invention said evacuation openings may include ventilations means for compensating the back pressure of the exhaust gas occasioned by its passage through the heat exchange means and the connecting tubings. These ventilation means may preferably be situated at the proximity of the evacuation openings of the heat exchanger.

Typically, but not restricted thereto, said container may comprise a parallelepipedical outer housing and an essentially cylindrical inner housing, whereby a free space is formed between said inner and outer housings through which the exhaust gas can freely flow.

In order to permit to use the transportation system according to the present invention under varying temperature conditions under which more or less energy of the exhaust gas is needed in order to continuously maintain the temperature of the transported substance above its melting point without, however, running the risk of insufficient heating during cold periods, a removable heat insulating coating is provided for the exhaust of the truck.

Alternatively or additionally, the amount of heat energy required to maintain a certain temperature of the transported substance may be controlled, whereby said connection means comprises an evacuation tube which is controlled by a throttle valve.

The control of the heat energy transferred to the transported substance may be automatically controlled by a system including a heat sensor which is provided at the interior of the inner housing, said sensor being connected to a heat control means, which is connected to said throttle valve.

In order to make the control of the gas volume, which is to enter into the heat exchanger, as efficient as possible, said evacuation tube is connected to the entry side of said connection means, where the gas pressure and temperature are the highest.

In the embodiment using a heat insulating coating on the exhaust and/or the connecting tubing, said heat insulating coating may be comprised of a wrapped web of rock wool surrounded by a wrapped web of metal sheet which is fastened at its ends by means of a hose collar.

The invention also relates to a container for the use in a transportation system according to the invention as described above and which comprises a parallelepipedical outer housing, an essentially cylindrical inner housing, and a free space which is formed between said inner and outer housings, said free space together with the wall of the inner housing forming said heat exchange means. The container comprises also attachment means for the removable fixation of the connection tubings.

Finally, the invention relates to the use of such a container for the transport of petrochemical products, its derivates, for chemical products and for nutritional products.

Short description of the drawings: The invention will now be described in more detail with reference to the drawings, whereof Fig. 1 illustrates a conventional transportation system for substances having their melting point close to or above the environmental temperature; Fig. 2a illustrates a first embodiment of the invention; Fig. 2b illustrates another embodiment of the invention; Fig. 2c ilustrates a third embodiment of the invention; Fig. 3 illustrates a top view of Fig. 2a, and Fig. 4 illustrates a cross sectional view of the container according to the invention.

Detailed description of the invention: A conventional truck-trailer for the transport of containers is depicted in Fig. 1 and comprises a truck 1 and a trailer 2 including a container 8. The truck includes a drivers house 3 and structural beams 16 and 17 which support the connection unit 15 for swiveling connection of the front portion of the trailer on the structural beams of the truck.

The truck further comprises a typically upwards directed exhaust system 7 having a free end 6 on top and being connected to a nonrepresented truck engine by its lower end 4, a silencer 5 being interposed between portions 4 and 6.

The trailer also comprises structural beams 13 and 14 which support the container. The container is comprised of an outer, parallelepipedical housing 19 which lodges, at its interior, an essentially cylindrical inner housing 10, whereby a free space 9 is left primarily in the corners of the outer housing 19. A container of this kind is described in more detail in copending EP application no.

96103920.3 The wall 18 of the inner housing 10 is supported by leg portions 11 which assure safe positioning of the inner housing in a central position within the outer housing, so that the inner housing is entirely surrounded by the free space 9, which is used to circulate heating gas for the transfer of heat energy into the substance which is contained within the inner housing and by which this substance may be reheated and possibly reliquified if solidified after filling.

Traditionally, such containers are transported to their destination and temporarily stored to discharge their contents, before which these contens must, in most cases, be reheated in order to assure a proper discharge operation.

The reheating takes place by connecting a burner or any other supply of hot gas to the attachment means 12c of a tube 12 forming an entry opening for the free space 9, whereby the heating gas is then evacuated through an exit opening which, in Fig. 1 is positioned at the same end of the container behind tube 12.

The inner housing 10 which is supported by leg portions 11 may contain a substance which only requires heating at the bottom area of the cylindrical inner housing. This is illustrated in Fig. 1 and 2b, where the free space between the lower portion of the inner housing and the bottom of the outer housing is limited laterally be leg portions which extend along the entire length of the container, so that, as seen in Fig. 4, the free space 9a into which the heating gas is injected through openings 12 and 12' simultaneously, rest confined within this free space 9a without flowing all around the inner housing.

Alternatively, as shown in Figs. 2a and 2c, the leg portions may be separated into a number of legs lla through 1 led, which permit the heating gas to practically freely flow all around the inner housing 10.

A manhole 50 is illustrated in Fig. 2b, 3 and 4 for the filling of the container as well as for cleaning and maintenance reasons. A similar man hole is also present in the containers according to the other figures, although not shown.

Similarly, not-shown evacuation openings are present at the lowest point of the inner housing for discharging of the transported substance.

According to the invention it is not necessary to supply reheating energy to the container after the transport, but to continuously use waste heat of the exhaust system of the truck to constantly keep the temperature of the transported substance sufficiently above the melting point to guarantee a smooth discharge operation at the destination of the load.

Figs. 2a, 2b, 2c and 3 illustrate a transportation system according to the invention, wherein a connection means 20 is provided between the exit 6 of the exhaust system of the truck and the attachment means 12c of the container in order to guid the hot exhaust gases through the heat exchanger of the container which is formed by the free space 9 between the inner and outer housings 10 and 8.

In Fig. 2a the free end 6 of the exhaust 7 of the truck is connected to the end 21 of a pipe 20 which includes several portions such as portion 22 (visible in Fig 3 only), portion 23, 24 and 25, portion 26 (also visible in Fig. 3 only) which separates the exhaust gases into two portions, as well as portion 27 which is connected to portion 28 of larger diameter in order to fit with the attachment part 1 2c of entry opening tube 12.

The exhaust gases are thus led into the free space 9 of the container, transfer a portion of their heat energy to the wall 19 of the inner housing 10 and leave said free space 9 by means of evacuation openings 12a and 12b (Fig 3).

These evacuation openings are provided with ventilation means 30a and 30b which provide assistance for the discharge of the exhaust gases from the free space 9 in order to reduce or eliminate the back pressure of the exhaust gas occasioned by its passage through the connection tubings 21-27 and the container, so as to maintain the pressure of the exhaust gases at the exit 6 of the conventional exhaust system 7 at the same value which it would assume if there were no connection means 20 and free space 9 to be traversed.

Fig. 2c shows an embodiment of the invention wherein the exhaust system 7 as well as the connection means 20 is entirely wrapped with a heat insulating coating. In cold countries, the temperature of the exhaust gases which leave the end tube 6 and which is typically about 1300C may not be sufficient to maintain the temperature of the transported substance at a level above its melting temperature.

Here it may be advisable to apply a heat insulating coating around the entire or a part of the exhaust system and/or the connection tubings 21-27 in order to raise the temperture of the exhaust gases at the exit point of tube portion 6 to as much as 4000C.

In non-illustrated manner, the inner and/or outer housings may of course also be provided with a heat insulating coating.

Such heat insulating coatings 60 may easily be applied around round structures such as the considered tubings by wrapping a web of rock wool around the tubes and covering the rock wool with a wrapped web of metal sheet, whereby the end portions of these wrapping may be secured by means of hose collars 61.

In another embodiment as shown in Fig. 2b, an automatic control is provided for the maintenance of the temperature of the transported substance at the desired level.

In this embodiment a temperature sensor 42 is located at the interior of the inner housing so that it is embedded in the transported substance. A cable leads from this sensor 42 to a nonshown sealed wall connector which permits to lead the signal of the sensor 42 through the wall of the inner housing 10 to the exterior thereof to a temperature control unit 43, whereby the connection from the sealed wall connector to the unit 43 leads through the wall of the outer housing which, however, does not require a sealed passage. The temperature control unit 43 is electrically connected to the magnet coil 40 of a throttle valve 41.

The operation of this automatic control is the following: When the temperature of the transported substance is too low, the sensor 42 produces a signal representing this status and the unit 43 produces a control signal to close the throttle valve.

Since the position of the throttle valve governs the amounts of exhaust gas which may escape into the environment and the amount thereof which is led into the container, the closing of the throttle valve produces a raise of the amount of exhaust gas which enters the container, and the temperature of the substance in the inner housing therefore raises. Alternatively, if the temperature of the substance in the inner housing becomes too high, the throttle valve opens and the amount of exhaust gas which is led into the container, decreases.

The invention has been described in detail hereinabove with reference to examples of embodiments which should not be construed as limiting the scope of the invention. Numerous modifications as to the form and shape of any of the illustrated or described structural or functional elements may be made without departing from the spirit of the invention which is defind as the use of readily available waste energy for heating a transported substance.

Claims

Claims:

1. Transportation system for the transport of substances having their melting point essentially similar to the temperature of the environment during transportation, including a container (8) for the substance to be transported, said container including a heat exchange means (9, 9a, 18) for the transfer of external heat to the substance within the container (8), said container being supported by a truck such as e.g. a trailer-truck (1, 2), characterized in that said system comprises a connection means (20) from the exhaust (7) of the truck to entry openings (12, 12') of the heat exchange means of the container, the warm exhaust gases of said truck being led into said heat exchange means through said entry openings (12, 12') and leaving said heat exchange means through evacuation openings (12a, 12b).

2. The transportation system of claim 1, wherein said evacuation openings (12a, 12b) include ventilations means (30a, 30b).

3. The transportation system of claim 1 or 2, wherein said container (8) comprises a parallelepipedical outer housing (19) and an essentially cylindrical inner housing (10), a free space (9, 9a) being formed between said inner and outer housings.

4. The transportation system of any one of the preceding claims, wherein a removable heat insulating coating (60) is provided for the exhaust (7) of the truck (1).

5. The transportation system of any one of the preceding claims, wherein said connection means (20) comprises an evacuation tube (21') which is controlled by a throttle valve (40, 41).

6. The transportation system of caim 5, wherein a heat sensor (42) is provided at the interior of the inner housing (10), said sensor being connected to a heat control means (43), which is connected to said throttle valve (40, 41).

7. The transportation system of claim 5 or 6, wherein said evacuation tube (21') is connected to the entry side of said connection means (20).

8. The transportation system of any one of claims 4 to 7, wherein said heat insulating coating (60) comprises a wrapped web of rock wool surrounded by a wrapped web of metal sheet which is fastened at its ends by means of a hose collar (61).

9. Container for the use in a transportation system according to any one of claims 1 to 8, characterized in that it comprises a parallelepipedical outer housing (19) and an essentially cylindrical inner housing (10), a free space (9, 9a) being formed between said inner and outer housings, said free space (9, 9a) together with the wall (19) of the inner housing (19) forming said heat exchange means (9, 9a, 18), said container further comprising attachment means (12c) for the attachment of the connection means (20).

10. Use of the container of claim 9 for the transport of petrochemical products and its derivates, for chemical products and for nutritional products.