Fuel coal and fuel gas united heat supply method

Abstract

The invention relates to a coal-gas combined heating supply method, belonging to HVAC area. The first step of said method is that small peak-shaving boiler with burning gas, as peak-shaving thermal source, running with the parallel of central heat network, is set in each thermal station of civil thermal network with the heat source, which is the boiler in the huge heat supply or coal-burning region. Said secondary backwater is that first heat exchanger obtains quantity of heat generated by the boiler of coal-burning thermal power station or huge coal-burning region and transmitted by the first pipe network, and then it is heated furthermore by small gas-burning peak-shaving boiler so that independent adjusting in time on each heat supply region is accomplished. Thermal resource only bears the basic load of heat supply and the lack of heat is compensated by small gas-burning peak-shaving boiler in each thermal power station. The heat value is changed as the relation of climate and requirement changes. Said first network also bears adjusting action.

Description

technical field [0001] The invention relates to a coal-fired gas combined heating method, which belongs to the field of heating, ventilating and air-conditioning. Background technique [0002] In order to improve energy utilization efficiency, many cities have vigorously developed central heating systems using cogeneration and large coal-fired boilers as heat sources. At the same time, in order to protect the environment, cities with conditions began to develop gas heating. However, at present, there are cities with two different energy sources of gas and coal for heating at the same time in China. The operation mode is either that the gas and coal-fired heating systems are independent systems and are not connected with each other, or the gas-fired boilers are installed in the large heating network once. side, as a peaking heat source. In this way, the following problems exist: [0003] (1) For large-scale central heating networks without peak-shaving boilers or with smal...

AI Technical Summary

Problems solved by technology

[0003] (1) For large-scale central heating networks without peak-shaving boilers or with small peak-shaving capacity, the operating efficiency is low in the early and late cold seasons

During this heating period, due to the small heating demand and the excess heating capacity of the thermal power plant, steam extraction from steam turbines has been replaced by condensing gas for power generation. The energy efficiency has dropped significantly, and under some working conditions it is even lower than that of boiler heating.

At the same time, the transmission capacity of the heating network is excessive, and the pump consumption of the quality adjustment system increases;

[0004] (2) For the gas and coal-fired independent heating system, the coal consumption of the coal-fired heating system changes with the weather, which will cause concentrated emission of pollution during the severe cold period, and the number of days when the air pollution exceeds the standard will increase;

[0005] (3) High heating cost

Under the same environmental effect, the current heating method consumes a large amount of natural gas and the cost of heating is high

[0006] (4) The safety of heating supply is poor. Once there is an accident in the centralized heat source or the main network, the entire heating system will be affected

[0007] (5) For the heating system where the peak-shaving boilers are centrally installed in the primary network for peak-shaving, it is difficult to adjust the heating network

For large-scale heating networks, general boiler start-stop switching is very difficult for hydraulic scheduling. At the same time, due to the large thermal inertia, it is not easy to achieve rapid adjustment at the end, and it increases the energy consumption of heating network transmission, and it is even difficult to achieve the required operating conditions;

[0008] (6) For gas and coal-fired independent heating systems, heat users charged for gas heating are much higher than those for coal-fired or combined heat and power generation, which is not conducive to social fairness

At present, the fuel cost of coal and gas is several times different, and consumers of gas heating are completely required to pay the cost of improving the atmospheric environment, which is not in line with the principle of social fairness and is not conducive to the promotion of "coal to gas"

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