泥浆对造纸废水的混凝沉降作用

以泥浆为吸附主剂、明矾为混凝剂 ,通过混凝沉降试验探索消除造纸工业废水中的污染物的途径和方法 .研究表明 ,每5 0 0 m L造纸废水加入 3 0 m L 红土泥浆 ,充分搅拌 ,静置 2 h后 ,移出 45 0 m L上层液 ,再加入 4m L明矾饱和溶液 ,充分搅拌 ,静置 2 h后 ,水体 p H值为 6左右、SS低于 14 0 mg·L- 1、CODCr低于 80 mg· L- 1、浊度低于 2 ,均可达到第二类污染物最高允许排放浓度标准 .     

Policy issues in agroforestry: technology adoption and regional integration in the western Brazilian Amazon

Agroforestry systems (AFS) have received much attention from policymakers and others for their perceived ability to contribute significantly to economic growth, poverty alleviation, and environmental sustainability. Yet in many areas of the developing world where AFS have proven their agronomic potential, they have yet to be widely adopted. This paper approaches the issue with a focus on one such area – the western Brazilian Amazon, an area where economic integration within the region itself, across national boundaries, and between the region and the rest of Brazil (’regional integration‘) may soon vastly shift incentives to natural resource users. The paper addresses AFS adoption via a conceptual framework that argues for scrutinizing agronomic and socioeconomic characteristics of AFS and their potential adopters. This framework facilitates a priori assessment of whether specific AFS will be adopted, and if so, by whom and with what likely impact on the development objectives at hand. It highlights characteristics that lend socioeconomic and agronomic ’agility‘ – connoting flexibility to easily shift production systems and accompanying marketing strategies in response to unforeseen or rapid change (due to qualities of the AFS itself, or the producer). Financial performance indicators (net present value of AFS during establishment and for the life of a project, and years to positive cash flow) are presented for selected AFS, and juxtaposed to a livestock production system that is already gaining wide adoption in the area. This juxtaposition illustrates the practical effects of socio-economic and agronomic characteristics posited as influential. Against this backdrop, trends in ’regional integration' are discussed, along with implications this integration process has for AFS adoption. The paper ends with a discussion of the roles and limitations of policy in promoting AFS adoption. This revised version was published online in June 2006 with corrections to the Cover Date.     

硫酸盐草浆黑液制粉状活性炭的研究

本文探讨硫酸盐草浆纸厂黑液的治理和利用,提出用酸化法从黑液中沉析木素制取粉状活性炭。大约生产10t草浆可制取1t优质粉状活性炭。同时还含有占总碱量24%的Na_2S可回收。排出的废液即使不再经过处理,其污染程度也已大大降低。     

宜兴市官林污水处理厂工艺设计

介绍了宜兴市官林污水处理厂的工艺设计过程，该污水厂针对处理对象的水量和水质采用了循环式活性污泥法。     

Agroforestry systems in North America

Agroforestry systems in North America vary widely in terms of components (tree, forb, graminoid, and shrub species) and outputs. Most of the agroforestry systems used in North America have emphasized wood and livestock production. The objective of each system has been to produce annual and long term economic returns and sustainable yields. Inputs such as fossil fuels, fertilizers, herbicides and pesticides are relatively low compared to those used in conventional agriculture.Major agroforestry system types in each of eight North American regions are described. The major species used as vegetational components in each system are enumerated by region. The numerous variations in how these components are mixed have created an almost endless number of actual systems. Management problems and solutions, economic concerns, and system comparisons have also been addressed for each region.     

竹活性炭处理六价铬废水的试验研究

用竹子加工的下脚料制得的竹活性炭,对六价铬废水进行净化处理。结果表明,竹活性炭对六价铬废水处理效果良好,实验探讨了竹活性炭处理六价铬废水的一般规律及影响因素。     

The Chagga homegardens: a multistoried agroforestry cropping system on Mt. Kilimanjaro (Northern Tanzania)

The homegardens are characterised by an intensive integration of numerous multipurpose trees and shrubs with food crops and animals, simultaneously on the same unit of land.The Chagga are skilled farmers with an intimate knowledge of the crops and their ecological requirements. They have a good idea of functions/uses of the plant species on their farms. The large species diversity provides both subsistence and cash crops. It enables the farmer to keep his management options open and provides insurance against drought, pest and economic risks.     

连续辊压中密度纤维板废水处理系统工艺设计

针对黑龙江兴隆中密度纤维板有限公司年产5万m3连续辊压中密度纤维板生产线废水的水质特点,采用混凝-厌氧-好氧相结合的废水处理工艺。运行结果表明,该废水处理系统运行稳定,最终出水指标达到了GB 8978-2002《污水综合排放标准》中的二级标准,净化后的水不仅能在厂内循环利用,而且产生的活性污泥还可以作为企业副产品销售,具有良好的环境效益和经济效益。     

德国畜禽产业发展及屠宰管理概述

德国畜牧业发达,在保障本国,甚至欧盟的畜禽产品供应上发挥了重要作用。本文介绍了德国畜禽产业发展的基本情况,总结了德国在畜禽屠宰管理方面的基本原则和成功做法,以期对我国畜禽产业发展和屠宰管理提供参考和借鉴。     

Mitigation of nitrous oxide (N2O) emission from swine wastewater treatment in an aerobic bioreactor packed with carbon fibers

Mitigation of nitrous oxide (N₂O) emission from swine wastewater treatment was demonstrated in an aerobic bioreactor packed with carbon fibers (CF reactor). The CF reactor had a demonstrated advantage in mitigating N₂O emission and avoiding NOx (NO₃ + NO₂) accumulation. The N₂O emission factor was 0.0003 g N₂O‐N/gTN‐load in the CF bioreactor compared to 0.03 gN₂O‐N/gTN‐load in an activated sludge reactor (AS reactor). N₂O and CH₄ emissions from the CF reactor were 42 g‐CO₂ eq/m³/day, while those from the AS reactor were 725 g‐CO₂ eq/m³/day. The dissolved inorganic nitrogen (DIN) in the CF reactor removed an average of 156 mg/L of the NH₄‐N, and accumulated an average of 14 mg/L of the NO₃‐N. In contrast, the DIN in the AS reactor removed an average 144 mg/L of the NH₄‐N and accumulated an average 183 mg/L of the NO₃‐N. NO₂‐N was almost undetectable in both reactors.