本文關鍵詞： 廢紙 液化 包膜控釋肥 油菜盆栽 降解　出處：《山東農(nóng)業(yè)大學》2017年碩士論文　論文類型：學位論文

【摘要】：相對于傳統(tǒng)水溶性化學肥料,包膜控釋肥能夠顯著提高肥料的利用率,降低肥料淋溶帶來的環(huán)境問題。但控釋肥的高成本以及包膜材料的難降解是阻礙控釋肥應用推廣的重要因素。因此,針對上述兩大重要問題,降低包膜控釋肥的成本、選擇可生物降解的包膜材料成為新型肥料研制的熱點。利用生活中廣泛存在的天然高分子如廢紙、秸稈等制備生物基可降解高分子包膜材料,包膜后的控釋肥具有優(yōu)異的控釋性能,且包膜材料具有低成本、生態(tài)環(huán)保等優(yōu)點。因此,本文選用廢紙作為主要原料,對液化方案進行優(yōu)化,制備了液化廢紙包膜材料,并通過轉鼓包膜工藝制得了液化廢紙包膜控釋肥。通過紅外光譜、熱重分析、掃描電鏡對液化物、膜材料的性能及微觀結構進行了研究,通過靜水浸提實驗研究了控釋肥料的養(yǎng)分釋放性能及機理;采用盆栽試驗觀察了控釋肥的施入以及殘膜殘留對油菜的生長發(fā)育和土壤的影響并研究了殘膜的降解機理。主要研究結果如下:(1)單因素優(yōu)化試驗得出液化條件:液固比為10:1(溶劑:廢紙,w/w)、溶劑比為2:8(EG:EC,w/w)、液化時間為1.5 h、液化溫度為160℃、催化劑用量為液化劑的3%(w/w),在此條件下,廢紙的液化率最高。同時在25℃靜水浸提方式下評價了包膜控釋肥的養(yǎng)分釋放性能。研究發(fā)現(xiàn),在最優(yōu)條件下得到的包膜控釋肥的控釋效果最好,且養(yǎng)分釋放期為84天。(2)通過廢紙、液化物、聚多異氰酸酯、聚氨酯的FTIR分析可知,廢紙在液化過程中發(fā)生了分解,并與液化劑發(fā)生反應生成了廢紙多元醇。聚氨酯上NCO基團的消失表明廢紙液化物上的OH和聚多異氰酸酯上的NCO發(fā)生反應合成了聚氨酯。(3)對控釋肥包膜材料進行表征,研究了廢紙液化物中羥基值與異氰酸酯基的不同摩爾比對膜材料性能的影響。研究發(fā)現(xiàn),當[OH]/[NCO]摩爾比為1.05:1時,所得包膜材料性能最佳。從PCU的SEM電鏡照片可以看出膜殼與尿素接觸緊密,包膜材料表面均勻光滑、結構致密,膜斷面幾乎看不見任何微孔和裂紋。(4)通過包膜厚度對控釋肥的養(yǎng)分釋放性能的影響研究發(fā)現(xiàn),當包膜率為3%時,控釋肥的養(yǎng)分釋放曲線呈倒“L”型,養(yǎng)分釋放較快,釋放期較短。當包膜率達到7%時,肥料的養(yǎng)分釋放期為84天,養(yǎng)分釋放曲線呈“S”型,與植物的生長曲線相一致。(5)通過土埋降解試驗分別對土埋6和12個月的殘膜降解情況進行了研究。發(fā)現(xiàn)土埋后的包膜材料發(fā)生了降解,且隨著時間的延長降解趨勢更加明顯。(6)采用油菜盆栽試驗,研究了控釋肥的施入以及殘膜殘留對油菜生長及品質和土壤的影響。通過試驗對比可以看出,控釋肥與殘膜的施入不僅提高了油菜的產(chǎn)量、改善了油菜的品質,還對改善土壤性質有一定的促進作用。
[Abstract]:Compared with the traditional water-soluble chemical fertilizer, coated controlled-release fertilizer can significantly improve the fertilizer efficiency. Reducing the environmental problems caused by fertilizer leaching, but the high cost of controlled-release fertilizer and the difficult degradation of coated material are the important factors that hinder the application and popularization of CRF. Reducing the cost of coated controlled-release fertilizer and selecting biodegradable coated material has become a hot spot in the development of new fertilizer. Biodegradable polymeric coating materials were prepared by straw. The coated controlled release fertilizer has excellent controlled-release properties, and the coating material has the advantages of low cost, ecological environmental protection and so on. In this paper, waste paper was selected as the main raw material, the liquefaction scheme was optimized, the liquid waste paper coating material was prepared, and the liquid waste paper coated controlled-release fertilizer was prepared by the rotary drum coating process. The infrared spectrum and thermogravimetric analysis were used to prepare the liquid waste paper coating controlled release fertilizer. The properties and microstructure of liquefaction and membrane materials were studied by SEM. The nutrient release performance and mechanism of controlled-release fertilizer were studied by hydrostatic extraction. Pot experiment was conducted to observe the effects of controlled release fertilizer application and residual film residues on the growth and development of rape and the degradation mechanism of residual film. The main results were as follows: 1). Single factor optimization test obtained liquefaction conditions: liquid-solid ratio is 10: 1 (solvent: waste paper). W / w, the solvent ratio is 2: 8 EGW / w / w, the liquefaction time is 1.5 h, the liquefaction temperature is 160 鈩，

本文編號：1473296