厨余垃圾工业化产沼工艺各阶段固态残余物营养特性研究

Study on Nutrient Characteristic of Solid Residues at Various Stages of Industrialized Biogas Production Process of Kitchen Waste

根据最新的垃圾分类国家标准,厨余垃圾又被细分为家庭厨余垃圾、餐厨垃圾和其他厨余垃圾。厨余垃圾经过分选、粉碎、厌氧发酵等产沼工艺会产生大量的残余物,其中主要包括三相分离固渣、厨余分离机固渣、湿式沼渣和干式沼渣。三相分离固渣和厨余分离机固渣的pH呈酸性,若作为有机肥料或绿化用有机基质,其含水率过高,pH、有机质和总养分基本符合要求。湿式沼渣和干式沼渣的pH呈碱性,若作为有机肥料,其含水率过高,pH、有机质和总养分基本符合要求。厨余垃圾固态残余物的pH、电导率和发芽指数之间的相关性较高。三相分离固渣和厨余分离机固渣建议采用厌氧发酵、好氧发酵、能源化利用技术、制备饲料蛋白技术、制备工业原料、人工饲养昆虫等方法处理后再利用。湿式沼渣和干式沼渣建议采用好氧堆肥、热解气化处理、人工饲养昆虫、能源化利用技术、制备中链脂肪酸技术等方法处理。同时也均可采用多种技术相结合,协同处理。

According to the latest national standard for waste classification,the kitchen waste is subdivided into household kitchen waste,food waste and other kitchen waste.Kitchen waste would produce a large amount of residues after the biogas production process of sorting,crushing and anaerobic fermentation,which mainly included three-phase separation solid residue,kitchen waste separator solid residue,wet biogas and dry biogas.The pH of three-phase separated solid residue and kitchen waste separator solid residue was acidic,if used as organic fertilizer or organic substrate for greening,its water content was too high,while pH,organic matter and total nutrients basically met the requirements.The pH of wet digestate and dry digestate was alkaline,and if used as organic fertilizer,its water content was too high,pH,organic matter and total nutrients basically met the requirements.The correlation between pH,electrical conductivity and germination index of kitchen waste solid residue was high.Three-phase separation solid residue and kitchen waste separator solid residue were recommended to adopt anaerobic fermentation,aerobic fermentation,energy utilization technology,preparation of feed protein technology,preparation of industrial raw materials,artificial feeding insect treatment and other methods to treat first then to use.Wet digestate and dry digestate were recommended to treat by aerobic composting,pyrolysis gasification treatment,artificial breeding insect technology,energy utilization technology and medium-chain fatty acid preparation technology,etc.Meanwhile,it could also use a combination of technologies for synergistic treatment.