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361.
综合利用造纸废渣和污泥的新方法 总被引:1,自引:0,他引:1
造纸废渣和污泥的综合利用是保护环境促进造纸业生产发展的重要课题。以废渣生产墙体材料不仅技术可行,而且获得了显著的经济效益。通过实例介绍,实现了清洁生产、循环经济和可持续发展的目的。 相似文献
362.
在造纸生产中应用助剂,可以把抄纸排水中原本泄漏掉的细小纸浆纤维回收并转化为产品.一方面削减了造纸废水中的污染负荷、减轻了水处理的压力,同时提高了纸品的质量和产量,给企业带来了显著的经济效益.因此,应该大力提倡在造纸生产中使用造纸助剂. 相似文献
363.
在分析了普通混凝剂的基础上,研究了聚合氯化铝(PAC)对造纸废水的处理效果。混凝试验结果表明,聚合氯化铝对造纸废水的处理达到较为理想的效果。 相似文献
364.
A process simulation of a high grade coated paper mill has been developed as part of a process integration study. Data necessary to calibrate and validate the simulation developed with the Cadsim Plus® software were obtained by: measurements, samples analysis and estimations through partial and local mass balances. The simulation was designed in a way that allows grade changes to reproduce the mill operation. The simulation is used to support process studies to optimise water and raw materials consumption and to evaluate results obtained by mathematical optimisation. Different scenarios were studied in order to evaluate the feasibility and the effects of process redesign of the mill's networks. 相似文献
365.
废纸回收的意义及脱墨剂市场前景 总被引:4,自引:0,他引:4
主要阐述了废纸回收的重要意义,介绍了脱墨剂的基本组成及脱墨工艺并对脱墨剂的市场进行了详细调查。 相似文献
366.
367.
Plant vintage, technology, and environmental regulation 总被引:4,自引:0,他引:4
Wayne B. Gray Ronald J. Shadbegian 《Journal of Environmental Economics and Management》2003,46(3):384-402
We use data on productivity and pollution abatement costs at individual pulp and paper mills to test whether the impact of environmental regulation on productivity differs by plant vintage and technology. Plants with higher pollution abatement costs have significantly lower productivity levels. This relationship differs greatly based on a plant's technology, with productivity at integrated mills being greatly affected by abatement costs, while the impact at non-integrated mills is negligible. Plant vintage does not seem to matter, with older and newer plants showing similar impacts. Reported abatement costs appear to substantially understate the true costs of abatement. Accounting for the impact of technology differences makes some difference in the estimated overall impact of environmental regulation. 相似文献
368.
In much of sub-Saharan Africa (SSA), the lack of organic soil amendments constitutes one of the principal causes for declining soil fertility in intensifying farming systems. The challenge, therefore, remains to increase the availability of organic inputs and to develop recommendations for their combination with inorganic fertilizers. An on-farm experiment was conducted in the northern Guinea savanna of Nigeria to evaluate the fertilizer effect of rice (Oryza sativa L.) mill waste (RMW) on a degraded Alfisol. The decomposition and nutrient (N and P) release patterns of RMW were studied using the litterbag technique, and the effect on maize yield and soil properties was determined. The RMW was applied at rates of 0, 5, 10, and 15 Mg DM ha−1 and was applied either unburnt or burnt (farmers’ practice). In both years, compound fertilizer was broadcast during land preparation on all plots at rates of 40 kg N ha−1, 17 kg P ha−1, and 33 kg K ha−1.Results obtained in the litterbag study showed that, at maize harvest, more than 90% of the P had been released from the decomposing RMW. However, around 60% of the organic C and 45% of the N still remained. Compared to the control treatment (0 Mg ha−1 RMW), which yielded 0.55 Mg ha−1, maize (Zea mays L.) grain yields were increased by 95% when 10 Mg ha−1 of unburnt RMW was applied, and by 147% with 15 Mg ha−1 (mean of 2 years). In contrast, burnt RMW did not result in significant yield increases. The cumulative application of 30 Mg ha−1 of unburnt RMW significantly increased the soil organic carbon in the surface soil from 0.7% (0 Mg ha−1 RMW) to 1.3%.The results of this investigation indicate that RMW constitutes a valuable organic input in the Guinea savanna if applied unburnt at rates of 10–15 Mg ha−1 in combination with inorganic fertilizer. The repeated application of unburnt RMW may contribute to the rehabilitation of degraded soils through the buildup of soil organic matter. 相似文献
369.
通过向土壤施加15N标记的莴笋残体(处理R)、废纸浆(处理P)及二者混合物(处理RP),并利用不同的压力使其成为3种不同容重处理的土壤样本,进行密闭培养,定时测定土壤N2O排放量及土壤溶液中NO3-与NH4 的动态变化,以探讨N_2O的产生与调控机制.结果表明,8d N2O释放量为R处理最大,RP处理其次,P处理最小.短期内(8d)R处理N2O释放最大量为空白对照(CK)的15倍,增加了土壤反硝化作用;P处理在同期内不能增加N2O释放量,证明这种废纸浆可少量(<2.5%)施用于农田中.RP与CK、P处理比较,可以刺激微生物活性和增加土壤反硝化作用;与R处理相比较,可以增加氮的固定.增加有机质的添加量使同一容重水平的RP处理N2O释放量高于R处理.70%的土壤样本随容重增加N2O释放量增加.土壤容重的增加同时影响了废纸浆的分解速率和土壤溶液中NO3-与NH4 浓度. 相似文献
370.
电解法处理造纸清黑液的研究 总被引:1,自引:0,他引:1
采用电解法处理造纸清黑液,利用电解氧化去除水中有机物,降低废水的COD.电解槽中电流密度,氯离子含量、pH值、电极板间的距离等是影响电解处理效果的重要因素.采用氢氧化钙对电解处理后的清黑液进行苛化处理,处理后废水可以用于蒸煮. 相似文献