Air drying system and working method of biomass capable of efficiently recovering waste heat

Abstract

Provided is an air drying system and a working method of biomass capable of efficiently recovering waste heat, pertaining to the field of energy conservation. The system is mostly composed of an air drying subsystem for biomass and an organic-fluid Rankine cycle subsystem for waste heat recovery. The organic-fluid Rankine cycle subsystem for waste heat recovery utilizes a non-azeotropic refrigerant (12) and adopts a sensible heat regenerator (5) and a latent heat regenerator (6) to recycle latent heat and sensible heat of wet and hot air at the outlet of a drying box (4) stepwise. The latent heat and sensible heat are converted into mechanical energy by means of an expansion machine (16). The mechanical energy cannot only satisfy the requirement of low-power consumption of a compressor (8) but also can output a part of useful power outwards. Compared with a conventional independent air drying system for biomass and an independent low-temperature organic-fluid Rankine cycle system, the system can utilize low-grade hot-drying biomass and have higher efficiency of heat-work conversion by means of stepwise recovery of waste heat, which is especially suitable for an improvement on the air drying subsystem for biomass.

Description

technical field [0001] The invention relates to a biomass air drying system and a working method for efficiently recovering waste heat, belonging to the field of energy saving. Background technique [0002] The large amount of moisture contained in biomass is the main reason for its perishability and intolerance to storage. Air drying is one of the common and effective methods to increase the storage life of biomass. However, since the dry air sweeps over the surface of the wet biomass to remove its moisture, a large amount of external heat energy is required to provide the latent heat of moisture evaporation in the wet biomass. Therefore, the energy consumption of the conventional air drying process is high. Therefore, how to reduce the energy consumption of the air drying process is of great significance for reducing the production cost of dry biomass. At present, there are some energy-saving air drying methods. For example, a part of the waste heat energy of the air at t...

AI Technical Summary

Problems solved by technology

At present, there are some energy-saving air drying methods. For example, a part of the waste heat energy of the air at the outlet of the drying box is recovered by a regenerator to preheat the dry air. Heat and latent heat quantities are higher, but of lower grade

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