Manure and litter handling technologies aimed at reducing greenhouse gas emissions (review)

One of the environmental problems associated with the accumulation of manure and litter is the emission of greenhouse gases. During the storage and processing of manure and litter, emissions of three main greenhouse gases occur – carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). In addition, there are also emissions of ammonia (NH3), which is not a greenhouse gas, but belongs to the 4th class of hazardous chemicals. Reducing the amount of their emissions is an important condition for increasing the environmental friendliness of the livestock industry. The aim of the review was to identify technological methods aimed at reducing greenhouse gas and ammonia emissions on the basis of the expert analysis of scientific and technical information sources. It has been noted that at the stage of manure storage it is effective to cover the surface of the manure storage, to separate the manure into solid and liquid fractions with their subsequent separate processing, to acidify the liquid fraction using treatment facilities for the adsorption of ammonia. When analyzing the manure processing technologies, it has been established that the most accessible is its composting with a moisture-absorbing carboncontaining material. In order to reduce the emission of greenhouse gases and ammonia, it is advisable to use active (accelerated) composting technologies carried out in biofermenters of various designs. The most effective from an environmental point of view there should be recognized such processing technologies as anaerobic fermentation and biochar production, which are carried out in closed-type devices. The indirect effect of biochar on greenhouse gas emissions is manifested in a decrease in nitrous oxide emissions from the soil when it is added as an agro-ameliorant and used as an additive in composting. The application of the described technologies in intensive livestock farming will contribute to the fulfillment of the requirements of the Paris Agreement and the relevant legislative acts of the Russian Federation.