| The research is linked with the Provincial Department of Science and Technology Research Project "Research of Key Technology ofBiomass Enqueuing and Relative Equipment Industrialization Technology". Through the systematic study of "volvement of biomass briquetting press (hereinafter refers to BBP)", "major design parameter of hydraulic straw briquetting press", "kinetic characteristics of straw and briquettes combustion", "improvement design of hydraulic BBP", "technology of biomass briquette combustion equipment and its application", data related to biomass briquetting have been achieved, and the rules concluded.The major achievements are:1 After reading a large amount of technical materials, the author made a comprehensive study on the following fields: (1) compression theories; (2) factors that have impact to biomass briquetting process; (3) mechanism of biomass briquetting; (4) technical processes of biomass briquetting; (5) existing technology of biomass briquetting and current situation of research; (6) problems occurred in existing biomass briquetting technologies. Through comparison of various compression equipment, the author believes that the design thought of bi-direction hydraulic compression of the HPB-1 BBP made by Henan Agricultural University is feasible.2 Using HPB-1 BBP model as experimental device and purposely changing some parameters of the components, the author has found the factors that influence the productivity and energv consumption rate. By regression of experimental data, therules of the linkage between these factors, which will provide a theoretical basis for designing BBP with different scales.3 Using thermal analysis technology and dynamic thermogravimetry, the paper studies combustion kinetic characteristics of 3 types of agricultural crops at different rate of temperature rise, and thus, achieved dynamic parameters of these fuels at different rate of temperature, established dynamic model of straw combustion, which reflects the dynamic process in the fast combustion area.4 Characteristics of straw briquette combustion was experimented, focusing on the impact of straw type, temperature, air supply, and density, diameter, and weight of briquette on the combustion speed, and the following conclusions were drawn: (1) combustion of straw briquette fuel is static permeation diffusion combustion; (2) temperature has a larger impact on the speed of straw briquette combustion than air supply; the higher the combustion temperature is, the faster volatilizable component separates out, and the less steady the combustion is; (3) density of briquette fuel has impact on the speed of volatilizable component separation and therefore the combustion speed; (4) increase of diameter and weight of briquette fuel increases the average combustion speed in the initial stage, and that in the later stages is comparatively steady; (5) the proportion of volatilizable component in straw briquette fuel is high, therefore, the temperature control during combustion under the rational ventilation condition is essential to ensure its safe combustion.5 Using the above-mentioned results of experiments and theoretical analysis, and based on thought of hydraulic driven and bi-direction compression, the hydraulic system and compression parts of the HBP BBP are re-designed in terms of industrialization. By adopting double-level pre-compression mechanism, the productivity reaches 500 kg.h"1, energy consumption rate reduces to 60 kwh.t",repairing period of wearing parts is around 300 hours. Thus, the technical problem that obstructs the dissemination of biomass briquetting technology in China is basically resolved.6 After the experiment and analysis of combustion characteristics of straw briquette fuel, the author designed a new small water boiler and has experimented the combustion performance with briquette fuel of different diameters. The study of relation of fueldiameter, chamber size, and combustion performance provided the scientific and practical basis to the identification of ration...
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