ENERGY POTENTIAL AND FEATURES OF GRAIN DUST BIODEGRADATION DURING ITS PROCESSING INTO BIOGAS

Abstract

The composition of the dust that is generated during the collection, transportation, processing and storage of grain is different and complex. The amount of grain dust can reach 26% by weight of the raw material. Due to the ability to ignite spontaneously, it is classified as a hazard class 3, and if it enters the human body, it can cause harm to health, therefore, grain processing enterprises take measures to reduce the concentration of grain dust in the air. On the other hand, the dust generated during grain processing is, due to its chemical composition, a valua- ble raw material, the loss of which is undesirable. The world literature describes such methods for processing aspiration grain dust as hydrolysis and the preparation of nutrient media for microorganisms, briquetting and combustion, use in composting, as well as conversion into biogas. The purpose of this work is to study the features of processing aspiration grain dusts of various agricultural crops into biogas and determine their energy potential and biodegradability. As a result of our laboratory studies, it was established that the specific biogas and methane yield from soybean grain dust was 186.37±58.89 – 230.30±21.90 and 95.54±36.95 – 122.17±15.39 ml/g VS respectively; from barley grain dust – 165.06±9.37 – 191.41±5.65 and 86.45±6.37 – 100.18±6.65 ml/g VS respectively. The concentration of methane in biogas in different variants ranged from 46.75±7.14 to 52.75±1.60%. When recycling 1 ton of these grain dusts at a biogas station, you can get from 278.70 to 382.25 kW of electrical energy and from 285.50 to 391.57 kW of thermal energy. The degree of decomposition of organic matter of substrates in our study is generally low – from 5.61±0.08 to 5.91±0.37%. Thus, it has been established that the grain dusts studied in this work can be considered as a promising cosubstrats for existing or planned biogas stations. The recommended processing time is no more than 35 days.