Sustainability and Efficiency

The fossil load factor is an important issue and its origin so evident and often unavoidable that we asked ourselves the question what the consequences are when this factor is reduced to zero. Whenever, in a biomass conversion process, a fossil fuel contribution was spotted, we replaced this contribution by one from biomass origin. For example, the process may require electricity, which is supplied by a nearby coal-fed power station. Then this amount of electricity was thought to be generated by a power station fed by biomass. Or the process may require heat or chemicals and again biomass is the raw material from which these requirements were met. Dr. Feng Wei made such an analysis for a process where a diesel-type product was obtained from wood chips as a feedstock. His work has been discussed as an example at the end of Chapter 13. 

Feng Wei is a professor at Beijing University of Chemical Technology. He performed this work during an extended research period at the Delft University of Technology as guest of one of the authors (JdSA). 

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In both the materials used and the construction process, sustainability and efficiency will become standard. Improvements mjob site management and building design will reduce waste and cost of construction. Materials such as engineered wood, recycled carpeting, and cellulose insulation, which have lower environmental impact, will become cheaper and more widely available. Not only are buildings constructed with such material friendlier to the environment, they also provide higher-quality, lower-cost solutions. 

Tilman D. Global environmental impacts of agricultural expansion The need for sustainable and efficient practices. P Natl Acad Sci USA. 1999 96 5995-6000. DOI 10.1073/pnas.96.11.5995... 

This chapter describes a number of industrialized case studies, illustrating how conhnuous processing methods have been used to sustainably and efficiently manufacture a broad range of pharmaceutical intermediates and two achve pharmaceutical ingredients (APIs). 

Thus, it would appear that at present the organic standards have been introduced before all of the scientific data required to make a successful change to sustainable and efficient organic production are available. Currently the relevant data have to be extrapolated from conventional poultry production practices until all of the required data are available. 

Today, 50 years since their discovery, the triazine herbicides continue to be critical tools for sustainable and efficient agricultural technology throughout the world. 

In process engineering, we need to be much more precise. What do we mean by green chemistry, green plastics, or green fuels In this chapter, we present a scientifically based method to make a proper assessment to what extent a process is "green," that is, sustainable and efficient. Some examples will be given for illustration. 

In this chapter, we will focus on the sustainability and efficiency of processes, and show that what seems or is meant to be green not always turns out to be green, sometimes against our intuition. As is common in this book, thermodynamics and some of its most relevant concepts will be used to analyze claims on the achievements of a process or route. The claim will be made that a product or process can only be called "green" after a proper assessment has been made. Often, such an assessment has necessarily a multidisciplinary character with contributions from disciplines with which we may be less familiar. 

In exploring what elements make a network sustainable and efficient, it might be worthwhile to look across to one of the most successful networks in the modern world, the Internet. Crucial elements of the Internet such as the digital packet switching are based on the research of Paul Baran conducted in the early sixties. In the era of the Cold War, the RAND (research and development) project was set up to define an information system that would resist a military attack. Within this project Baran deducted that from all constellations investigated,... 

The problems associated with the environmentally safe, sustainable and efficient disposal of waste continue to grow. In many areas, existing landfills are beginning to fill up, and the cost of disposal continues to increase while the types of wastes accepted at municipal solid waste landfills is becoming more and more restricted. One answer to all of these problems lies in the abihty of society to develop beneficial uses for these waste products. 

It is generally accepted that cyanobacterial TCA cycle is not very active under phototrophic conditions. A recent study further proved that it operates in a bifurcated way [112]. However, the bifurcated pattern switches to a dominantly cyclic pattern by introducing an ethylene-forming enzyme from Pseudomonas. Ethylene can be sustainably and efficiently produced from 2-oxoglutarate while also activating the TCA cycle metabolism. The enhanced flux via the remodeled TCA is 37% of the total fixed carbon which is higher than the 13% found in wild type. This result indicates that the metabolic malleability of the cyanobacterial TCA cycle depends on what it produces. 

Clearly, the energy demands of society need to be satisfied in a more appropriate, sustainable, and efficient way. Gleaner devices for energy conversion are batteries and fuel cells. They operate more efficiently, produce less pollution, are modular, and are less likely to fail mechanically since they have fewer moving parts than energy conversion based on combustion. 

Cheng S, Logan BE (2007) Sustainable and efficient biohydrogen production via electrohydrogenesis. Proc Natl Acad Sci 104(47) 18871-18873. doi 10.1073/pnas.0706379104... 

BuUd Back Better signifies an ideal reconstruction and recovery process that delivers resilient, sustainable, and efficient recovery solutions to disaster-affected communities. The motivation behind the Build Back Better concept is to make commimities stronger and more resilient following a disaster event. Statistics from the United Nations Enviromnent Programme in 2008 show an increase in the number of natural disasters over time attributing to growing populations. 

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