Optimising the environmental benefits of emission reductions from UK coal- and oil-fired power stations: a critical loads approach

This paper describes a method for determining reductions of SO₂ emissions from coal- and oil-fired power stations, oil refineries and large industrial units in the UK taking into account their pollution potential. The method is based on the use of two gridded data sets: critical loads, which represent the sensitivity of the environment to acid deposition and modelled estimates of total (wet + dry) sulphur deposition for 646 point sources within the UK. An iterative method is used to identify and subsequently reduce emissions from point sources that contribute most to areas of critical loads exceedance. This paper demonstrates how the method may be used to determine an optimal allocation of emissions across the UK which yields the maximum amount of environmental protection per unit of emission.The paper then goes on to consider the changes that will have to take place within the UK power generation industry in order to meet the revised EC Large Combustion Plant Directive which comes into force on 1 January 2008. Particular emphasis is placed upon proposed emissions trading schemes and the environmental implications of allowing trading between stations with high and low pollution potentials. The paper concludes by suggesting that the emissions trading process should take into account the pollution potential of each source, irrespective of whether the proposed emission is within the plant's agreed emission limit. An approach based entirely on minimizing environmental damage rather than one which takes cost into account, as in current integrated assessment modelling, could provide an interesting approach across the rest of Europe.     

New eco-friendly proposal for the crystallization of beet raw juice

In the past years we evaluated different strategies with the aim of eliminating completely from the beet sugar factory, the traditional calco-carbonic purification process taking into account the well-known problems related to the utilization of lime and the production of carbonation sludge.To complete the picture of the possible solutions to be adopted for the elimination of the traditional purification process, we tested and evaluated in laboratory and in pilot plants a new eco-friendly proposal.The results obtained, as well as the proposed flow-sheet and some economic evaluations, are presented and discussed.     

The market-incentive recycling system for waste packaging containers in Taiwan

This paper presents a new market-incentive (MI) system to recycle waste-packaging containers in Taiwan. Since most used packaging containers have no or insufficient market value, the government imposes a combined product charge and subsidy policy to provide enough economic incentive for recycling various kinds of packaging containers, such as iron, aluminum, paper, glass and plastic. Empirical results show that the new MI approach has stimulated and established the recycling market for waste-packaging containers. The new recycling system has provided 18,356 employment opportunities and generated NT$ 6.97 billion in real-production value and NT$ 3.18 billion in real GDP during the 1998 survey year. Cost-effectiveness analysis constitutes the theoretical foundation of the new scheme, whereas data used to compute empirical product charge are from two sources: marketing surveys of internal conventional costs of solid-waste collection, disposal and recycling in Taiwan, and benefit transfer of external environmental costs in the United States. The new recycling policy designed by the authors provides a reasonable solution for solid-waste management in a country with limited land resources such as Taiwan.     

Ecological modelling Internet resources

Internet resources are grouped into registers and sources of ecological models (6 addresses), sources of documents (7), sources of data (5), initiatives (5), societies (4), journals (4) frequently asked questions (7), extensive list of links to Web pages (4), search engines (5) and Usenet groups (10). At present, Internet resources are not replacing classical libraries but should be considered as complementary sources of information.     

The classification of lands managed for conservation: existing and proposed frameworks, with particular reference to Australia

Comprehensive classification systems to accurately account for lands managed for biodiversity conservation, are an essential component of conservation planning and policy. The current international classification systems for lands managed for nature conservation are reviewed, with a particular emphasis on Australia. The need for a broader, all-encompassing, categorisation of lands managed for conservation is presented and a proposed broader categorisation system is developed—the Conservation Lands Classification. This classification system has the advantage of incorporating data on both tenure and protection mechanisms and has been applied in this paper using conservation lands in three Australian jurisdictions as examples. It is envisaged that this method of classification has the potential to significantly improve the ability to measure current and future trends in nature conservation across all land types at a variety of scales and hence is put forward in order to stimulate discussion on this important topic.     

Simulation and optimisation of a high grade coated paper mill

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.