王煌平, 张青, 章赞德, 罗涛, 翁伯琦, 钟少杰. 不同热解温度限氧制备的畜禽粪便生物炭养分特征[J]. 农业工程学报, 2018, 34(20): 233-239. DOI: 10.11975/j.issn.1002-6819.2018.20.030
    引用本文: 王煌平, 张青, 章赞德, 罗涛, 翁伯琦, 钟少杰. 不同热解温度限氧制备的畜禽粪便生物炭养分特征[J]. 农业工程学报, 2018, 34(20): 233-239. DOI: 10.11975/j.issn.1002-6819.2018.20.030
    Wang Huangping, Zhang Qing, Zhang Zande, Luo Tao, Weng Boqi, Zhong Shaojie. Nutrient characteristics of biochar prepared from animal manures at different temperature with limited oxygen[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2018, 34(20): 233-239. DOI: 10.11975/j.issn.1002-6819.2018.20.030
    Citation: Wang Huangping, Zhang Qing, Zhang Zande, Luo Tao, Weng Boqi, Zhong Shaojie. Nutrient characteristics of biochar prepared from animal manures at different temperature with limited oxygen[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2018, 34(20): 233-239. DOI: 10.11975/j.issn.1002-6819.2018.20.030

    不同热解温度限氧制备的畜禽粪便生物炭养分特征

    Nutrient characteristics of biochar prepared from animal manures at different temperature with limited oxygen

    • 摘要: 为了分析畜禽粪便生物炭中的养分特征变化,以鸡粪、猪粪渣和牛粪为原料,采用限氧控温法制备生物炭,研究了不同热解温度(350、450、550、650和750 ℃)的畜禽粪便生物炭灰分含量,C含量、大量和中微量元素养分含量及其残留率的变化,并分析了C/N比值,原材料与炭化产品养分含量、及热解温度和生物炭养分特征的相关性。结果表明,随着热解温度的升高,畜禽粪便生物炭C、N含量逐渐下降,灰分含量和P、K、Ca、Mg、Fe、Mn养分含量逐渐增加。高温热解虽增加畜禽粪便生物炭的养分总量和C/N比值,但也降低了各养分残留率。综合分析表明,畜禽粪便生物炭养分含量及其残留率与原材料中的养分含量、热解温度密切相关,其中与热解温度相关性显著。因此,选择高C和高养分含量的畜禽粪便原材料是提升生物炭养分含量的基础,而适宜温度是保留生物炭较高养分残留率的关键。该研究中畜禽粪便适宜热解温度为450 ℃,该温度下各生物炭的养分残留率整体表现为牛粪>猪粪渣>鸡粪。

       

      Abstract: Compared with traditional manure composting, the pyrolysis of livestock manures is one of the thermochemical technologies for converting biomass into nutrient-rich biochars with potential agronomic uses, and reduces the environmental problems caused by fecal accumulation. Studies are needed to clarify biochar nutrients properties across manure varieties under similar controlled conditions. Of all parameters affected the biomass pyrolysis process, temperature is one of the most important factors. In this study, three types of biochars derived from chicken manure (CM), solid-liquid separated pig manure (PR) and dairy manure (DM), were prepared by pyrolyzing at different temperatures (350, 450, 550, 650 and 750 ℃), under an oxygen-limited condition in muffle furnace. The effects of temperature on the ash content, total carbon content, macro to micro nutrients contents and their remaining rate of biochars were analyzed. Meanwhile, the C/N ratio, the correlation of nutrient contents between raw materials and carbonized products, and the relationship between pyrolysis temperature and nutrient characteristics of biochars were also discussed. The results showed, as pyrolysis temperature increased, the biochar carbon (C) and nitrogen (N) contents decreased, while the contents of ash, phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn) in biochars gradually increased. When pyrolysis temperature reached 750 ℃, the C and N contents decreased by 8.25%-19.86% and 59.62%-70.71%, respectively. Due to the decrease of volatile matter contents, the increased ash contents ranged from 43.28% to 57.65% at this temperature. The contents of P, K, Ca, Mg, Fe, Mn in biochars increased by 85.84%-128.54%, 85.03%-123.26%, 68.66%-169.03%, 33.02%-123.30%, 63.92%-103.62% and 56.92%-75.19% at 750 ℃, respectively. All nutrient differences reached a significant level (P<0.05). Although high temperature pyrolysis increased the total nutrient content and C/N ratio of manure-derived biochars, it also reduced the remaining rate of nutrients. When the pyrolysis temperature increased from 350 to 750 ℃, the residue rates of C, N, P and K in biochars decreased significantly by 58.25%-76.07%, 85.01%-88.23%, 33.31%-69.54% and 40.27%-71.29% (P<0.05), respectively. Those of Ca, Mg, Fe and Mn also reduced significantly by 45.18%-71.21%, 47.22%-73.52%, 40.84%-70.91% and 39.19%-68.11% (P<0.05). In general, the nutrient contents and their remaining rates in biochars were closely related to material source and pyrolysis temperature, and the correlation between nutrient characteristics and pyrolysis temperature was significant (P<0.05). Therefore, the selection of high C and high nutrient contents of animal manure, was the basis for improving the biochar nutrient contents, and suitable temperature was the key to retain the high nutrient residue rates of biochars. When the temperature increased from 450 to 550 ℃, the nutrients loss rates ranged from 20.12% to 71.23%, and the decrease was most obvious, indicating that the suitable temperature for manure pyrolysis was 450 ℃. Overall characteristics of biochar nutrients at this temperature, the selection of livestock manures for nutrient-rich biochars production was in order of DM > PR > CM in this study. Future studies focusing on other factors and the persistence of biochar fertility in the field must explicitly take into account additional factors to transfer this technology.

       

    /

    返回文章
    返回