Thermal compensation type superheated steam coal drying system

Abstract

The invention discloses a thermal compensation type superheated steam coal drying system. Fault raw coal is broken and screened through a coal breaker, then passes through a coal bunker and then enters a superheated steam fluidized bed, the heat and mass transfer process is carried out inside, then the fault raw coal flows out of the bottom of the superheated steam fluidized bed, and the fault raw coal becomes upgraded coal after passing through a coal cooler. Superheated steam of the superheated steam fluidized bed is from a superheated steam extraction source. Water in the fault raw coal is heated and evaporated in the superheated steam fluidized bed into secondary steam, then the secondary steam is output out of the top of the superheated steam fluidized bed, the secondary steam passes through a circulating fan and then is introduced into the superheated steam fluidized bed to be subjected to heat exchange with the raw coal again, and the secondary steam becomes precipitated water after being condensed. Cooling feedwater introduced into the coal cooler serves as compensation heat source water to be introduced into a waste-heat heat exchanger and a solar heat exchanger through corresponding valves, wherein the waste-heat heat exchanger and the solar heat exchanger are connected in parallel. The waste-heat heat exchanger and the solar heat exchanger are both connected with an electric superheater through valves, and a superheated steam outlet of the electric superheater is connected with the superheated steam extraction source in parallel through a switching valve and then is connected into the superheated steam fluidized bed.

Description

technical field [0001] The invention belongs to the field of low-rank coal quality improvement technology and waste heat recovery application, and in particular relates to a thermal compensation type superheated steam coal drying system. Background technique [0002] Superheated steam coal drying is a new coal cleaning and upgrading technology. In superheated steam coal drying, the raw coal particles are crushed and screened to a certain extent, and the heat exchange with superheated steam and circulating steam is performed to complete the upgrading function. It has low energy consumption, high thermal efficiency, and no dust pollution. Pulverized coal catches fire and explodes, and the upgraded coal has good porosity and combustion characteristics. Reducing the energy consumption of the coal upgrading system to meet the clean and efficient combustion utilization is the key technology for the clean utilization of low-quality coal, including lignite. The research and applic...

AI Technical Summary

Problems solved by technology

The superheated steam drying system used to use reheating or heat pump system to increase the temperature and pressure parameters of the secondary steam. Although it has merits, it caused the complexity of the system and did not greatly reduce the energy consumption of the system.

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