JPS59145681A - Diesel tanker performing efficient tank heating - Google Patents

Abstract

PURPOSE:To save energy entirely by providing an auxiliary boiler in a tanker mounting Diesel main machine then leading the produced steam to a back pressure turbine while utilizing turbine exhaust for heating cargo tank. CONSTITUTION:In a tanker where a propeller 8 is driven by Diesel main machine 1, an auxiliary boiler 3 is provided to feed the produced steam to a back pressure type steam turbine 13. The propeller 8 is driven by thrust of main machine 1 through a clutch 21 and gear 12. Exhaust from the turbine 13 is fed through a regulating valve 14 to a a cargo tank heating tube 15 and an inboard heating source 16 then collected through a drain tank 17 and water supply pump 18. Exhaust gas energy from main machine 1 is collected by economizer 7 then fed through a pump 19 to a boiler 3. Exhaust gas from the back pressure turbine is utilized to obtain a heat source for cargo tank while saving energy.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an oil tanker that heats cargo tanks in an energy-saving manner in a diesel-main mechanical oil tanker that transports high viscosity cargo that requires periodic tank heating.

Conventionally, when heating the cargo tanks of an oil tanker, there are two heating methods depending on whether the propulsion engine type is a diesel main machine or a steam turbine main machine.

(1) In the case of a diesel main machine Figure 1 shows a tank heating system diagram when a diesel main machine with low fuel consumption is used for propulsion. In Figure 1, 1 is the diesel main machine, 2 is the cargo tank, 3 is the auxiliary boiler, 4 is the heating pipe, and 5 is the cargo tank. Since the amount of heating steam in tank 2 cannot be covered, a separate auxiliary boiler 3 is used to heat cargo tank 2.
This auxiliary boiler 3
In addition to the fuel needed for propulsion, additional fuel is required.

A normal diesel-powered oil tanker is equipped with an auxiliary boiler with a pressure of about 16 kg/cm' to drive the cargo pump turbine, but the pressure for heating the cargo tank is lower, about 4 to 5 kg/cm'. steam is sufficient.

In addition, the energy recovered from the exhaust gas of the diesel main machine is used to turn the generator 5, in order to save energy.However, in view of the turbine efficiency of the turbo generator 5, a condenser turbine is normally used to reduce the exhaust gas. The heat of condensation is discarded from the condenser 6 into the seawater, which hinders thermal efficiency. That is, the turbine inlet enthalpy is 660 k c a l
/ kg, exhaust enthalpy 615 k cal
/ kg, condensate enthalpy is about 40 kcal/kg, then the amount that can be used as energy is 660-615
=45kca 17kg remaining c7) 615-40
= 575 kcal 7 kg is wasted in seawater, and its thermal efficiency is extremely low.

(2) In the case of a steam turbine main machine As shown in FIG. 2, a main boiler 9 with good thermal efficiency is always operated, and steam for heating cargo tanks can be obtained at any time by branching from there. However, since the main boiler 9 generally generates 79% high pressure and high temperature, a heating device such as a low pressure steam generator stirrup 11 is required to lower the steam conditions to a pressure and temperature suitable for heating the cargo tank, which reduces heat loss. This is large and causes an increase in costs. The main turbine 10 for propulsion requires a condenser 6 for condensing υ1 steam, and a large amount of 'fJM6 heat is disposed of into seawater, so fuel efficiency is higher than that of a diesel main engine.

An object of the present invention is to save energy by improving the conventional cargo tank heating method and utilizing waste energy in the above-mentioned diesel-powered oil tanker with low fuel consumption.

The gist of the present invention is that a diesel-main mechanical oil tanker transports high viscosity cargo that requires constant tank heating, is equipped with a back pressure steam turbine, and uses the turbine exhaust for heating the cargo tank. A generator or a cargo pump is coupled to the steam turbine so that the output of the turbine can be used for a generator or propulsion support, and the cargo tank can be heated even when berthed. This oil tanker has a turbine and a propulsion shaft that are removably connected.

In the present invention, we focused on the fact that fuel consumption does not increase even if the boiler pressure is slightly increased, and we expand high-pressure steam from a high pressure to the J (power required for heating the cargo tank) using a back-pressure steam turbine. This system is characterized by extracting energy for a generator or for boosting propulsion to a propulsion plant, and using the back pressure steam to heat the cargo tank.

In a normal steam turbine, the exhaust gas is condensed in a condenser and the heat of condensation is wastefully discarded into seawater, but in the present invention, a cargo tank is heated instead of the condenser, thereby eliminating wasteful waste. The aim is to save energy by recovering the energy generated by heating the cargo oil.

The present invention will be explained in detail with reference to the following 12 pages.

FIG. 3 shows a system 12 according to an embodiment of the present invention. In FIG. 3, steam generated in the auxiliary boiler 3 is sent via a gear system 12 to a back-pressure steam turbine 13 mechanically connected to the main diesel machine 1. to drive the propeller 8.

The exhaust gas from the turbine 13 is adjusted to an optimal pressure by a back pressure regulating valve 14 and supplied to the cargo tank heating pipe 15 and other inboard heating sources 16.

Cargo tank heating saving 15 and other onboard heating @ 16
The steam supplied to the boiler is condensed in each device, becomes drain, is sent to the drain tank 17, and is returned to the boiler 3 by the water pump 18.

Working steam is generated in the auxiliary boiler, drives the back pressure steam turbine 13, and is supplied to the cargo tank heating at the set pressure of the back pressure regulating valve 14, where it expands until it condenses, becomes drain, and is sent to the boiler. Returned to complete the Rankine cycle.

During normal voyages, the steam generated in the exhaust gas economy 7 installed to recover waste gas energy from the main machinery 1 is collected in the boiler drum by the canned water 2 @ ring pump 19 and is used as a heat source for heating the cargo tank. Waste heat is used as part of the process.

The onboard power requirements are supplied by a shaft-driven generator 20 driven by the propulsion plant via gearing 12.

The back pressure steam turbine is mechanically attached to the
Because the engine is integrated with the engine, it provides additional propulsion and reduces fuel consumption. Of course, it is also possible to drive a generator. The oil tanker of the present invention can further save energy by using a waste heat recovery system from the υ1 waste of the diesel main machine.

FIG. 4 shows another embodiment of the invention. '34
In the embodiment shown in the figure, a generator 20 is connected to the back pressure steam turbine 13, and the steam turbine generator and a connecting shaft are detachably connected by a clutch 21.
Even when the oil tanker is at anchor, the cargo tank can be heated by using the auxiliary turbine 13. A cargo tank 18 may be coupled to the turbine 13 instead of the generator 20. In the embodiment shown in Fig. 4, during normal voyage, Franchise 21
This is the same as the embodiment shown in FIG. In the case of pre-viscosity cargo oil, it is necessary to heat the cargo tank even during unloading, so the clutch 21 is disengaged, the steam turbine 13 is disconnected from the propulsion plant, and the turbine drive generator 20 or the cargo tank 18 is driven by the steam turbine 13. As a result, the same effects as the embodiment shown in FIG. 3 can be obtained.

In the oil tanker of the present invention, for example, the back pressure of the turbine is set to 5 kg/
If c m', the exhaust enthalpy is 650 kc a
l/kg 660-650=10kcal/kg
As a result of the adiabatic heat drop, the amount of steam required for the back pressure turbine will be 4.5 times higher if the output is the same, ignoring internal efficiency, but since a large amount of steam is required to heat the cargo tank, a sufficient amount of steam can be secured. If this 5 kg/cm' of steam is used to heat the cargo tank, the cargo tank heating pipe will produce 150 kg/cm' of steam.
If we ensure a heat transfer area that can expand to a drain of k cal / kg, 650-150 = 500 kcal
/kg+7) Heat can be used, and if the train is returned to the boiler as feed water, the heat loss to seawater is O, totaling 510k.
Cal/kg of heat can be obtained, making it possible to use 11 times more heat than conventional methods.

Additionally, since there is no need for a turbine condenser or sea water for cooling it, construction costs are reduced, and power consumption is also reduced, resulting in significant energy savings.

[Brief explanation of drawings]

Figure 1 is a heat utilization system diagram of an oil tanker that heats the cargo tank of a conventional diesel main machine, Figure 2 is a heat utilization system diagram of a steam turbine main machine, and Figures 3 and 4 are examples of the present invention. This is a system diagram of ■...Diesel main machine, 2...Cargo tank 3...Auxiliary boiler 4...Heating tube 5...Turbo generator 6...Condenser 8...Propeller 9...Main Boiler 10...Turbine main machine 11...Low pressure 7A momme generator 12...Gear device 13...Back pressure type steam turbine 14...Back pressure regulating valve 15...Cargo tank heating pipe 16...・Inboard heating source 17... Drain tank 18... Water supply pump 19... Canned water circulation pump 20... Generator 21... Clutch patent applicant Mitsui Engineering & Shipbuilding Co., Ltd. agent Patent attorney Yoshio Kosugi

Claims (1)

[Scope of Claims]] Hatashi The present invention proposes to install an air turbine in the back pressure port in a diesel-main mechanical oil tanker that transports high viscosity cargo that requires tank heating, and to use the turbine exhaust for heating the cargo tank. Characteristic oil tanker. 2. The oil tanker according to claim 1, wherein the output of the turbine is used for a launcher or a propulsion engine. 3. The oil tanker according to claim 1, wherein a generator or a cargo pump is coupled to the front shear turbine, and the turbine and the propulsion shaft are detachably coupled.