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11.
利用固体废弃物生产商品砂浆   总被引:1,自引:0,他引:1  
陈海红 《北京农业》2011,(9):177-178
砂浆是一类重要的建筑材料,砂浆的商品化是建筑业实施节能减排的重要方面。发展商品砂浆可以实现节约资源、减少污染。  相似文献   
12.
李宏燕  续京 《安徽农业科学》2011,39(13):7692+7827-7692,7827
介绍MCGS工控组态软件的系统结构和功能,并结合宁夏南部山区马铃薯淀粉生产废水处理工艺,构建了其上位机监控系统,扩展了MCGS的应用领域。  相似文献   
13.
通过对该黑龙江省集贤县农村生活垃圾处理情况的调查,深切感到解决农村生活垃圾问题的重要性,对此提出了对策建议  相似文献   
14.
玉米秸秆炭和典型农业废弃物混合成型与燃烧特性试验   总被引:1,自引:2,他引:1  
以玉米秸秆炭和玉米秸秆、苹果枝、沼渣、菌渣为原料,在成型压力为6 MPa的条件下,研究了不同混配比例混合燃料的成型特性,并在此基础上探讨了特定混配比例下的混合样品燃烧特性。研究结果表明:农业废弃物质量分数、种类对混合成型燃料稳定性均有影响,农业废弃物占70%比例时混合成型燃料的抗跌碎强度均大于99.50%;玉米秸秆对成型燃料的稳定性影响最为明显,其质量分数大于30%时,成型燃料抗跌碎强度达到99.68%以上,而沼渣和菌渣质量分数大于50%时,其成型燃料的抗跌碎强度分别超过99.11%和99.71%;苹果枝质量分数大于60%,其成型燃料抗跌碎强度超过99.34%;4种成型燃料的能量密度与原料相比分别提高14.93、11.36、11.74、14.53 GJ/m3;堆积密度分别提高792.99、596.92、605.63、820.12 kg/m3。该研究为农业废弃物新型成型燃料的开发提供了基础支撑。  相似文献   
15.
保定市工业废水农灌的研究   总被引:1,自引:0,他引:1  
本文论述了保定市工业废水经农灌土地处理,对土壤、地下水和农作物品质的影响。结果表明:以造纸、食品、轻纺和化工为主的工业废水在重金属常年不超出农灌标准下,宜于在非盐化土壤灌溉;废水中硫化物超标,通过土壤生物区系,能降低毒性;废水中常规有机物,农灌后利大于害;只要在土壤容量允许内,可具有二级污水处理工艺不能完成的效果。  相似文献   
16.
A pot experiment was conducted to investigate the mobilization of sparingly soluble inorganic and organic sources of phosphorus (P) by red clover (Trifolium pratense L.) whose roots were colonized by the arbuscular mycorrhizal (AM) fungus Glomus mosseae and in association with the phosphate-solubilizing (PS) bacterium Bacillus megaterium ACCC10010. Phosphate-solubilizing bacteria and rock phosphate had a synergistic effect on the colonization of plant roots by the AM fungus. There was a positive interaction between the PS bacterium and the AM fungus in mobilization of rock phosphate, leading to improved plant P nutrition. In dual inoculation with the AM fungus and the PS bacterium, the main contribution to plant P nutrition was made by the AM fungus. Application of P to the low P soil increased phosphatase activity in the rhizosphere. Alkaline phosphatase activity was significantly promoted by inoculation with either the PS bacterium or the AM fungus.  相似文献   
17.
杨凌示范区城市生活垃圾的理化性质及处理对策研究   总被引:2,自引:0,他引:2  
为了确定合适的垃圾处理对策,依据城市生活垃圾采样和物理分析方法标准和相关的行业标准对杨凌示范区城市生活垃圾的理化性质进行了为期1年的分析研究。结果表明,垃圾各组分中可腐物占36.88%~55.32%,筛下混合物为15.76%~25.60%,无机物6.75%~35.36%,塑料6.9%~26.00%,垃圾的容重为215.4~429 kg.m-3,含水率为38.87%~53.21%,高位热值为10 082~24 467.6kJ.kg-1,低位热值为4 946~13 929.4 kJ.kg-1;可腐物和筛下混合物中总N为0.592%~2.046%,总P(P2O5)为0.192%~0.820%,总K(K2O)为0.796%~1.686%,重金属Cr为18.72~46.35 mg.kg-1,Cu为67.33~180.04 mg.kg-1,Pb为17.74~72.43 mg.kg-1,Zn为116.71~337.05mg.kg-1,As为9.05~24.14 mg.kg-1。在此基础上,提出堆肥加填埋是当前杨凌示范区生活垃圾最恰当的处理方案。  相似文献   
18.
为探讨抗旱保水袋在废弃采石场造林中的应用效果,通过室内试验和室外盆栽试验研究了抗旱保水袋性能及对容器苗生长的影响。结果表明:大袋保水袋的吸水速率和吸水倍数比小袋保水袋分别增加1.4倍、1.9倍,在蒸馏水溶液下的吸水速率和吸水倍数比自来水分别增加0.6倍、0.1倍;大袋保水袋的保水率大于小袋保水袋;保水袋能显著增加渣土土壤体积含水量,比对照高1.29倍,苗高平均比对照增加2.36cm,成活率平均比对照增加69.5%,出现死亡天数平均比对照推迟12d。结论得出,抗旱保水袋是干旱、半干旱及半湿润地区废弃采石场困难立地提高造林成活率并促进植被恢复的一种有效方法。  相似文献   
19.
Field trials were conducted at the Institute of Agricultural Research and Training Ibadan in 2000 and 2001 cropping seasons to evaluate the efficiency of some phosphorus (P) sources, rates, and frequency of application on grain yields of maize and cowpea grown sequentially. The experiment was laid out in a split–split plot arrangement using randomized complete block design, with three replications. The main plot was frequency of fertilizer application (seasonal and annual). Source of P [single superphosphate (SSP: 18% P2O5)]; Ogun rock phosphate (OPR: 20.21% P2O5), and crystallizer super (CS: 31.4% P2O5) constituted the subplots. The P rates (0, 20, 40, and 60 kg P ha?1) were the sub-subplots. An early maize cropping followed by a late-season cowpea was the sequential cropping, while an early maize followed by a late-season maize was the continuous cropping. The croppings were repeated the second year. Frequency of P application and source of P were significantly different while rates of application were not. Maize and cowpea grain yields from the control treatment were significantly less than yields from P-treated plots. Maize grain yields were slightly greater in plots alternated with cowpea, compared to continuous maize. Relative agronomic efficiency (RAE) values of OPR and CS were 67% and 75%, respectively, in annual application and 140% and 134% in seasonal applications, respectively, in 2000. In 2001, the trend was almost similar to 2000 except that there was a decline in RAE values of cowpea. Each Naira invested in the annual application returned about ?3.12 while about ?2.13 was returned with the seasonal application (?125.00 is the equivalent of USD$1.00). The OPR and CS can serve as alternatives to water-soluble sources such as SSP.  相似文献   
20.
ABSTRACT

Biochar, compost and their combination are important organic amendment materials for improving the hydro-physical properties of sandy soils. Series of soil columns experiments were conducted for investigating the application effects of date palm biochar and compost on evaporation, moisture distribution, infiltration, sorptivity (Sp), saturated hydraulic conductivity (Ksat) and water holding capacity (WHC) at application rates of 1%, 2%, 3% and 4% (10, 20, 30 and 40 g kg?1). The columns were filled manually with air-dried soil with 35 cm depth and the thickness of surface amended layer was 10 cm (T10) and 20 cm (T20) from soil surface at bulk density of 1400 kg m?3. The results showed that the behavior of soil moisture distribution was influenced by application of biochar, compost and biochar-compost mixture. Moreover, in the amended layer T10, applying biochar at rate of 1%, 2%, 3% and 4% reduced significantly cumulative evaporation by 5.8%, 10.8%, 12.8% and 16.1%, respectively. Meanwhile, the reduction for the biochar-compost mixture at application rates of 1%, 2%, 3% and 4% was 10%, 12.2%, 14.5% and 20%, respectively. In layer T20, applying biochar at rate of 1%, 2%, 3% and 4% reduced cumulative evaporation by 10.24%, 13.0%, 18.3% and 21.5% but this reduction amounted to 18.2%, 21%, 23% and 24% for the biochar-compost mixture, respectively. It was generally observed that the highest application rate (4%) for applied amendments was the most effective impact on Sp, Ksat and WHC compared with other rates.  相似文献   
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