怎样才能破解秸秆收储利用的瓶颈

<正>一、秸秆收储利用存在的问题1.现有的秸秆收储、利用装备技术不成套、不配套、效率低、成本高。主要表现在:秸秆捡拾打捆机效率低,收获、打捆机需要二次作业,尤其是夏季茬口十分紧张,农户难以接受;秸秆成捆后,草捆在田间的搬运乃需人力,缺少田间通行能力强、效率高的草捆搬运车辆;现有秸秆运输车辆主要以拖拉机拖车为主,装载量少,效率低,缺少专用的秸秆运输车辆。2.秸秆还田装备和技术体系不完备、不成熟,秸     

牵引式玉米秸秆切割揉碎方捆打捆机设计与试验

针对我国玉米秸秆收储、利用难及现有秸秆收获机械可靠性低、适应性差等问题,从切割揉碎打捆理论与试验研究角度,探明秸秆切割揉碎打捆作业技术。设计了一种对田间直立、铺放或散状整株玉米秸秆可一次性完成切割、揉碎、输送和打捆作业的牵引式玉米秸秆切割揉碎方捆打捆机。对牵引架、切割揉碎装置、网筛式物料导流装置和压缩打捆装置等关键部件进行了结构设计,并开展了样机试制及试验。试验结果表明,样机破节揉碎率91.3%,成捆率99.0%,秸秆捆密度167 kg/m3,规则秸秆捆率95.6%,秸秆捆抗摔率93.5%,样机作业性能良好,符合相关标准要求。研究成果实现了直立、铺放或散状整株玉米秸秆切割、揉碎和打捆一体化技术融合,可为秸秆打捆机的设计提供参考依据。      

草捆稳定性的影响因素试验研究*

针对玉米秸秆成捆后,收集搬运过程中易散捆的问题,从玉米秸秆草捆受力分析入手,分别研究了草捆静置、移位和变形过程中载荷的变化规律,以及影响草捆稳定性的因素;利用本团队开发的打捆试验台,开展了草捆密度、草捆长度和捆绳数量对草捆抗摔率影响的试验,确定了满足草捆质量稳定性的参数取值范围;通过响应面分析试验,确定了适合草捆收集搬运的最优参数组合为草捆密度为175 kg/m³,草捆长度为88 cm,捆绳数量为3根,草捆抗摔率为93.5%。草捆稳定性完全满足生产要求,为方捆打捆机的研究提供了理论指导。     

自解捆式果园秸秆覆盖机设计与试验

针对果园秸秆覆盖机不适应捆状秸秆、装载量小以及覆土装置易被碎石卡死问题,设计了一种自解捆式果园秸秆覆盖机。该机型由履带底盘、料箱、解捆铺料装置和覆土装置等组成。解捆铺料装置为齿带式结构,安装于料箱后部。为适应多种秸秆捆尺寸,提高抓料解捆能力和铺料均匀性,通过对解捆铺料过程分析确定了解捆铺料装置高度、倾角和齿带转速等关键参数范围;为了实现切绳和破捆过程滑切减阻,设计了三角形拨料刀齿,并基于刀齿对秸秆的扰动区域分析,对刀齿排布进行了设计;设计了一种双向对抛式覆土装置,同步对秸秆层进行薄土盖压。试验结果表明：覆盖机的秸秆装载量提高到原来的3.1倍;当覆盖机车速在0.8~1.4km/h,解捆铺料装置齿带转速在180~240r/min时,秸秆覆盖层厚度为5.1~18.1cm（标准差小于等于3.4cm）,薄土盖压层厚度为2.3~4.0cm,无卡死现象,满足作业要求;建立的秸秆覆盖厚度模型决定系数为0.9672。该机实现了秸秆解捆、行间覆盖与薄土盖压一体化作业。     

秸秆打捆机研究现状及发展趋势

我国农作物秸秆资源丰富,但利用率极低,目前大量秸秆被焚烧或废弃,不仅造成严重的环境污染,而且还浪费了宝贵的可再生资源。本文主要阐述了国内外秸秆打捆机的研究现状,现有秸秆打捆机如圆捆秸秆卷捆机、方捆秸秆打捆机的结构特点及优缺点,并对秸秆打捆机的未来发展前景做了简单浅析,为进一步研究和开发秸秆打捆机具提供参考。     

可变压捆室打捆机结构设计与仿真分析

针对传统秸秆打捆机收获农作物秸秆时形成圆草捆直径单一的问题，设计一种由捡拾机构、喂入机构、压捆机构和草捆卸载装置等组成的可变压捆室圆捆机。在Solidworks中建立可变压捆室圆捆机三维模型，简述其工作原理和关键部件的结构设计，并对整机动力传动系统进行分析；分析草芯在压捆室内累积过程，得出物料在压捆室内运动的规律，并通过计算得出钢辊线速度为2.29 m/s；运用ADAMS软件对打捆机进行运动学仿真，验证打捆机作业时不会发生物料堵塞和堆积现象，得到钢辊线速度为2.3 m/s，与计算结果基本一致；利用ANSYS Workbench软件对打捆机机架进行模态分析，得出打捆机正常作业时机架不会发生共振现象。为后续秸秆打捆机的创新设计和结构改进提供理论支持。     

小方捆秸秆切碎压捆打包机的设计

为提高作物秸秆商品化利用,设计了小方捆秸秆切碎压捆打包机。该机采用单缸柴油机作为动力,液压驱动方式,结构紧凑,通用性好,适应性强,可适用于玉米、高粱等作物秸秆的切碎压捆打包作业。试验结果表明:在机器稳定运行时,捆包密度平均为584.06kg/m3,打包成捆率约为100%,生产率为78包/h,作业质量符合设计要求;机具结构设计合理,为农作物秸秆综合利用提供了技术支持。     

自带传动动力恒频方草捆捡拾压捆机设计与试验

阐述了自带传动动力恒频方草捆捡拾压捆机的基本结构及工作原理,对压捆机的总体结构、捡拾器、输送喂入机构和压缩机构进行了结构设计和参数分析。试验结果表明：本机结构合理、自动化程度高,其成捆率达到了99.1%,规则草捆率为98%,草捆密度达到了130～230kg/m3,可对牧草、农作物秸秆进行捡拾、压缩和打捆联合作业。     

一种秸秆齐捆收集机的研制与推广

本文针对齐捆秸秆人工收集效率低、成本大等问题,研制了一种全自动秸秆齐捆收集机,详细介绍了该秸秆齐捆收集机的结构、工作原理和关键技术。通过试验验证,该秸秆收集机能显著提高齐捆秸秆收集效率,有效解决齐捆秸秆收集难的问题。     

小方捆机制作秸秆微贮饲料工艺

<正>秸秆微贮饲料,就是在农作物秸秆中加入生物高效活性菌种,并将其放入窖中进行厌氧发酵,从而使秸秆变成适口性好,消化率高、具有酸香味的微贮饲料.本文介绍的小方捆机制作微贮饲料工艺,是一种适合大型农牧场和大型饲养专业户采用的工艺.该工艺,经新疆农科院农机化所的科研人员两年的实践,效果良好,并已通过了自治区科委组织的科研鉴定.一、主要工艺路线小方捆机制作微贮饲料工艺路线如下:秸秆夺捆 → 入窖→封窖→发酵→出窖→揉碎→饲喂 ↑苗菌液配制→喷洒菌液二、主要机具的选择1.小方捆压捆机选用内蒙古宝昌牧机厂生产的9KJ—1.4A型小方捆捡拾压捆机,其生产率为3—5吨/小时,压捆密度250公斤/立方米.配套动力,可选用20.6千瓦以上的轮式拖拉机.2.水泵选用0.7立方米/分的小型潜水泵.3.贮水水箱,根据加工用水的情况而定,一般容量为2立方米.     

Temporal persistence of spatial soil-water patterns under trickle irrigation

Summary Trickle irrigation of perennial crops results in local wetting near trees and vines. Methods to measure soil-water content or storage within the root zone generally require intensive instrumentation to characterize spatial patterns of soil water adequately. The goals of this research were to determine if spatial patterns of soil-water storage under trickle irrigation are temporally presistent which may make it feasible to use less intense sampling to characterize total storage. Soil-water storage from the 0 to 1.5 m soil depth was measured at 23 sites on one side of trickle-irrigated almond trees using a neutron probe over three years in the San Joaquin Valley of California. Measurements were made on two trees in each of five different irrigation treatments. The persistence of spatial patterns with time was evaluated using Spearman rank correlation and relative differences from mean values. Spatial patterns were different for each tree and irrigation treatment but remained fairly persistent with time during a season. In many cases, temporal changes in soil-water storage were adequately estimated from a single location. Single sampling locations identified during one year gave estimates of mean storage during the following year with some increase in error. However, use of the same sampling locations for more than two years increased the error in storage estimates. Soil-water content or storage in trickle-irrigated orchards may be monitored by intense sampling during the early part of the irrigation season in order to identify locations giving mean soil-water storage. Only these locations may then be sampled to monitor changes in soil water.     

Do farmers waste fertilizer? A comparison of ex post optimal nitrogen rates and ex ante recommendations by model, site and year

While there appear to be costs to farmers of over-applying nitrogen, there is evidence in many regions that farmers are applying nitrogen at levels that exceed those suggested by government extension services. A major reason why farmers would apparently waste money by applying more fertilizer than a crop can use is a perception that the general recommendations are not appropriate for their individual situations. In this paper we estimate the economically optimal rates for 7 Ontario sites over multiple years using four yield response functional forms to examine whether the profit-maximizing rates as determined at the end of the growing season (ex post optimal rates) are generally higher than recommended rates due to site, year, or yield response functional form differences. There was no statistical or economic basis for selecting one response model over another suggesting functional form choice or perception is not a reason for over-application. However, there was a great deal of variability found between the actual optimal rate for the season and the ex ante recommended rate, which is constant across seasons for a given site. While the recommended rate is higher than the maximum economic rate of nitrogen (MERN) on the majority of sites examined, the distribution is skewed due to a few large differences. When the recommended rate is lower than the ex post MERN in a given year, it tends to occur on less productive sites and is much lower. The pay-off function to alternative nitrogen rates is generally flat as the difference between the MERN and recommended was less than $10/ha on approximately one-third of the trials but there are large differences in the good years on less productive sites. Thus, the decision to apply more than average to take advantage of the good years is appropriate since the cost of over-application is low compared to the cost of under-application. While the pay off to soil testing for nitrogen and consequently variable rate application technology is brought into question, there appears to be significant value to information on the growing conditions for the upcoming season particularly on less productive sites. Another implication of the study is the need to have a sufficient range of application rates in nitrogen field trials for accurate estimation of the underlying response function.     

生物结皮对土壤水气传输特性的影响

为研究生物结皮对土壤气体传输、水力传导特性的影响,在陕北水蚀风蚀交错区,以4种处理土样(无结皮、去结皮、3 a生结皮和7 a生结皮)为研究对象,进行土壤导气率、饱和导水率和入渗速率的测定分析.结果表明:在土壤吸湿和脱湿过程中,相同土壤含水率所对应的土壤导气率值不同,且脱湿过程的导气率值高于吸湿过程;生物结皮导致土壤导气率降低;由于生物结皮的存在,土壤总孔隙度和毛管孔隙度增加,在增强土壤持水性的同时降低了土壤的导水性;生物结皮生长年限越久,土壤水分入渗的能力显著降低;3种入渗模型中Horton模型的决定系数R²的值大于同处理下其他模型,该模型更适合于用来模拟该区域生物结皮覆盖下的土壤入渗特征.     

6 000 t拉伸矫直机拉伸头承载能力的研究

利用大型工程分析软件I-DEAS建立6 000t拉伸矫直机拉伸头--固定夹头和活动夹头实体几何模型,用弹簧单元模拟预紧螺栓,对拉伸头承载能力进行有限元计算,分析了预紧螺栓及其预紧力对设备承载能力的影响,并通过现场测试验证分析计算的结果.结果表明预紧螺栓的存在使设备承载能力提高25%以上,螺栓预紧力每提高1 000 kN,C形板应力值下降约2.5%,当螺栓预紧力控制在5 000 kN时,该拉伸机最大拉伸能力可达55 000 kN.在实际使用过程中,充分发挥和有效控制预紧螺栓的预紧力,防止预紧螺栓在拉伸过程中松动,以保证设备的安全运行.     

蔬菜栽培中连续施用猪粪沼肥的肥效与重金属风险研究

为探究沼肥在蔬菜种植中的肥效,在试验大棚中连续进行3季上海青-茄子轮作试验,设置低(BF-L)、中(BF-M)、高(BF-H)沼肥施用量,从产量、土壤特性和重金属风险的角度探讨沼肥替代化肥的效果以及沼肥高负荷土地消纳的阈值。结果表明,在上海青种植中沼肥组相较化肥组均减产6%左右,其中BF-M组的平均产量为沼肥组中最高(39.7 t/hm²),而在茄子种植中沼肥组的产量均高于化肥组,其中BF-H组的平均产量最高,达到58.3 t/hm²,相较化肥组增产27%。沼肥连续施用2年后,土壤的总氮、总磷含量出现了明显的升高,且升高幅度远高于化肥组,其中BF-M和BF-H组土壤总氮含量较原土壤升高84%和85%,土壤总磷含量升高3.4倍和3.2倍。但是沼肥施用对土壤总钾含量的提升效果并不明显,较原土壤只升高17%左右。另外,连续施用沼肥的土壤pH值更为稳定,能够有效缓解氮肥施用造成的土壤酸化问题,但沼肥施用组与化肥组均会导致设施栽培土壤EC较原土壤的升高,升高幅度均在70%以上,且随沼肥施用量的增加EC上升幅度增大,说明设施栽培中沼肥高负荷施用应关注土壤...     

不同秸秆覆盖量对春玉米冠气温差和叶水势日变化的影响

为了探明不同秸秆覆盖量对春玉米冠气温差(CATD)和叶水势(LWP)日变化的影响,在渭北旱塬设置了3种不同秸秆覆盖量(4 5009、000、13 500 kg/hm2),以不覆盖为对照(CK),研究了孕穗期春玉米冠气温差及叶水势的日变化。结果表明,4 500～13 500 kg/hm2覆盖量处理,较CK均能显著降低CATD、提高LWP(P0.05),尤其中午13:00—15:00效果最为明显。9 000 kg/hm2覆盖量处理综合表现最优,其日平均和14:00的CATD分别为0.79、-0.20℃,较CK依次降低了75.8%、111.4%,差异均显著(P0.05),15:00时LWP为-1.58 MPa,较CK增加7.06%(P0.05);其次为13 500 kg/hm2覆盖量处理,其日平均和14:00的冠气温差与9 000 kg/hm2覆盖量处理无显著差异(P0.05);4 500 kg/hm2覆盖量处理表现最差,与CK无显著差异(P0.05)。各处理冠气温差与秸秆覆盖量、土壤贮水量均呈显著负相关(P0.05)。研究认为,冠气温差可合理反映不同覆盖量条件下作物水分亏缺程度和土壤水分变化状况,且渭北旱塬适宜的秸秆覆盖量以9 000 kg/hm2为宜。     

保护性耕作示范效果监测研究

分析总结了农业部保护性耕作示范效果(10个县)2003年的监测成果。试验表明，保护性耕作的抗旱、保墒、培肥土壤、增产、增收和防治沙尘暴等都初见成效。尤其在旱地的效果更佳。试验未发现保护性耕作比传统耕作的病虫害严重，但免耕的杂草量比传统耕作的要多，经过施用除草剂可以得到控制。在保护性耕作的实施过程中，需要农艺与农机有机结合，不断创新和完善适合不同类型区的保护性耕作技术模式。     

黑土区施加生物炭对土壤综合肥力与大豆生长的影响

为探明黑土区施加生物炭对土壤持水性能、土壤养分以及大豆生长的影响,以东北黑土区3°坡耕地田间径流小区为研究对象,进行为期4年的观测。按照生物炭施加量,2015年共设置C0(0 t/hm~2)、C25(25 t/hm~2)、C50(50 t/hm~2)、C75(75 t/hm~2)、C100(100 t/hm~2) 5个处理,2016—2018年分别连续施加等量的生物炭。结果表明:连续4年,0～60 cm土层土壤储水量随施炭量的增加呈先增大、后减小的趋势,而对60～100 cm土层土壤储水量影响不显著;连续4年,饱和含水率随施炭量的增加呈逐渐增大的趋势; 2015年田间持水率、凋萎系数随施炭量的增加呈逐渐增大趋势,2016—2018年呈先增加、后减小趋势;连续4年,施加生物炭提高了大豆各生育阶段的株高和叶面积,同期相对较优处理分别为C75、C50、C50、C25;连续4年,大豆冠层覆盖度与施炭量呈抛物线变化(R~2均在0. 89以上,P 0. 01),连续施加2年的C50处理各生育期提高量最大,与C0相比提高了81. 4%、36. 7%、31. 5%和39. 6%;连续4年,土壤pH值和有机质、速效钾含量随施炭量的增加呈逐渐升高趋势,碱解氮、有效磷含量呈先升高、后降低趋势,相对较优处理为C50、C50、C25、C25。采用改进的内梅罗指数模型计算的土壤综合肥力指数与产量呈正相关(R~2=0. 861 5,P=0. 001 2,RMSE为0. 75),土壤综合肥力水平最高的生物炭施用模式为连续2年施加50 t/hm~2的生物炭。     

Centrifugation for separating piggery slurry 3. Economic effects on aerobic methods of odour control

The costs of reducing the odours from piggery slurries to an inoffensive level and storing that slurry in an inoffensive state are discussed. Five different combinations of aerobic treatment and separation for slurries containing initially between 1·5 and 8% d.m., from 2000 and 8000 pigs, and with storage for five days or 30 days are considered. The five combinations are aeration of raw slurry; separation then aeration; centrifugation then aeration; aeration of raw slurry then centrifugation; and separation then aeration then removal of more solids by centrifugation. The costs of storing the effluents from these processes are also included.For slurry from the smaller herd and for a short storage period, the cost of aerobic treatment of raw slurry is lower than other treatments when the slurry is less than 4·5% d.m. Using a brushed screen/roller press separator to remove solids before aeration produces the cheapest control of odours for slurries above 4·5% d.m.When 30 days' storage or more is required, separation before aeration is cheaper for slurries with more than 3% d.m. and the costs of using a decanting centrifuge (costing £38 000) before aeration is similar to aerating raw slurry at 6% d.m.With a large (8000 pig) herd, using the centrifuge before aeration to produce slurry that is inoffensive for 30 days is the cheapest method at all dry matter contents. When storage is required for only five days, separation or centrifugation before aeration have similar costs, these costs are similar to the cost of aerating raw slurry when it contains less than 3% dry matter, but as dry matter content of the raw slurry increases the cost rises steeply. Removing solids from slurry by centrifugation after aeration increases the overall costs compared to aerating raw slurry.     

浙江省海宁市同仁养殖场沼气发电综合利用工程及效益分析

养殖业的污染已经成为制约规模化养殖业可持续发展的重要因素。浙江省海宁市同仁养殖园沼气发电综合利用工程,日处理养殖污水60余t,年处理量达2.37×104t,可每年节省开支1.9万元。日产沼气500 m3,用于发电,年可发电32万度,每年可创收12.8万元。太阳能集热装置100.8 m2,每年可节省开支1.26万元。年产有机肥480 t,每年仅有机肥一项的收入就可达到28.8万元。沼液经管道输送,作为附近10 hm2示范桑园及13.3 hm2稻田有机肥,又可为农民节约2.8万元。沼液、沼渣等的使用可提高土壤有机质含量,改良土壤,有利于土地资源的可持续利用。