| Abstract [eng] |
In Lithuania, as well as in other European countries one of the main underlying objectives of biodegradable waste (BDW) management is source of all types separation from the generated BDW and its separate treatment. During last years the number of food processing companies, which either treat BDW at (near) the source of generation or produce new surplus value products, experienced a significant growth. The most widely applied BDW treatment methods are biological, which include fermentation and / or aerobic treatment processes and resulting in biogas and compost production. In this paper main attention is allocated to the aerobic food BDW treatment processes. It is really important to select and implement proper treatment technologies, to maintain optimal parameters of a technological process, thus avoiding the increase of the impact to environment and human health due to formation of air emissions, GHG’s, fetid odors and microbiological contamination. The objective of the Master project is to assess possibilities to reduce environmental impact of aerobic treatment BDW in food industry and to offer recommendations relevant to this industry. Object –aerobic treatment processesof BDW at food processing companies, incl. animal by-products (ABPs) This paper presents analysis of the following BDW treatment in food industry: - vegetable origin (food residues of sugar, oil, beer, juices, alcohol, confectionary and etc. processing companies); - animal origin (food residues of meat, fish, milk processing companies) (ABPs); - BDW, generated in catering companies (ABPs); - Degistates produced from different food BDW, incl. ABPs The final project presents an in-depth analysis of the scientific and technical literature. Chemical and physical characteristics of food waste, incl. ABPs, from food processing companies optimal for compost production were defined. Environmental as well as other legal requirements for both food BDW aerobic treatment and high value compost production, widely used and newest technologies for BDW aerobic treatment were analysed. This paper presents the methodology, which can be applied to evaluate the impact on air quality and climate change. Presented methodology integrates 3 methods : - estimation of air pollutants emission factors (kg tonne-1of BDW); - preparation of mass and energy balance - and comparative analysis. The methodology integrates both direct and indirect impact of air emissions (caused by the the additional usage of energy or due to the excess alternative energy production) on air quality, and climate change due to GHG emissions from various stationary and mobile sources within BDW aerobical treatment companies. Emissions’factors (EF) for the evaluation of air pollution and GHGs emissions in all processes were defined using 3 methods presented in EEA/CORINAIR, 2016 [8]; IPCC Guidelines, 2006[9] and obtained using the results measurements made at Lithuanian BDW treatment companies as well as results of analysis of scientific and technical literature. It was evaluated that open aerobic treatment of digestate has the biggest impact on air quality (up to 0.749 kg tonne-1of BDW), meanwhile the lowest impact is observed during BDW treatment in closed intensive systems at (near) the source of generation (for example: usage of Oklin technology) or during centralized composting, where aerated windrow cover systems, tunnels, boxes or containers with bio-filters are used. In this case, the amount of pollutants, which influence the eutrophication and tropospheric ozone formation processes is estimated to be < 0.11 kg tonne-1of BDW and ≤0,07 kg tonne-1of BDW respectively. It was estimated that the biggest impact on climate change due to GHGs emissions have open composting systems ( up to 242.5 kg CO2 eqv.tonne-1of BDW). The lowest impact on a global warming is observed in companies, where the technology of BDW fermentation is applied due to excess alternative energy production (up to 63.5 kg CO2 eqv.tonne-1of BDW), also in companies, where BDW treatment in closed intensive systems is used ( up to 77 kg CO2 ekv. tonne-1of BDW). This paper presents recommendations for food processing companies as well as catering companies how to reduce the environmental impact from air emissions and GHGs during food BDW treatment and production of new surplus value products. Integrated waste management view is applied in recommendations, starting with the elimination of food waste using Cleaner production preventional methods; minimization of BDWs, using proper treatment at (near) the source of generation and production of new higher value-added products, and finishing with proper separation and transfer to waste management companies, which apply the principles of industrial symbiosis in order to transform waste into new products. |
