Concrete is a composite material composed of aggregate bonded together with a fluid cement that cures over time. Concrete is the second-most-used substance in the world after water, and is the most widely used building material. Its usage worldwide, ton for ton, is twice that of steel, wood, plastics, and aluminium combined.
Recycling is the process of converting waste materials into new materials and objects. This concept often includes the recovery of energy from waste materials. The recyclability of a material depends on its ability to reacquire the properties it had in its original state. It is an alternative to "conventional" waste disposal that can save material and help lower greenhouse gas emissions. It can also prevent the waste of potentially useful materials and reduce the consumption of fresh raw materials, reducing energy use, air pollution and water pollution.
Industrial ecology (IE) is the study of material and energy flows through industrial systems. The global industrial economy can be modelled as a network of industrial processes that extract resources from the Earth and transform those resources into by-products, products and services which can be bought and sold to meet the needs of humanity. Industrial ecology seeks to quantify the material flows and document the industrial processes that make modern society function. Industrial ecologists are often concerned with the impacts that industrial activities have on the environment, with use of the planet's supply of natural resources, and with problems of waste disposal. Industrial ecology is a young but growing multidisciplinary field of research which combines aspects of engineering, economics, sociology, toxicology and the natural sciences.
Permeable paving surfaces are made of either a porous material that enables stormwater to flow through it or nonporous blocks spaced so that water can flow between the gaps. Permeable paving can also include a variety of surfacing techniques for roads, parking lots, and pedestrian walkways. Permeable pavement surfaces may be composed of; pervious concrete, porous asphalt, paving stones, or interlocking pavers. Unlike traditional impervious paving materials such as concrete and asphalt, permeable paving systems allow stormwater to percolate and infiltrate through the pavement and into the aggregate layers and/or soil below. In addition to reducing surface runoff, permeable paving systems can trap suspended solids, thereby filtering pollutants from stormwater.
Plastic recycling is the processing of plastic waste into other products. Recycling can reduce dependence on landfill, conserve resources and protect the environment from plastic pollution and greenhouse gas emissions. Recycling rates lag those of other recoverable materials, such as aluminium, glass and paper. Through 2015, the world produced some 6.3 billion tonnes of plastic waste, only 9% of which has been recycled, and only ~1% has been recycled more than once. Additionally, 12% was incinerated and the remaining 79% sent to landfill or to the environment including the ocean.
Concrete recycling is the use of rubble from demolished concrete structures. Recycling is cheaper and more ecological than trucking rubble to a landfill. Crushed rubble can be used for road gravel, revetments, retaining walls, landscaping gravel, or raw material for new concrete. Large pieces can be used as bricks or slabs, or incorporated with new concrete into structures, a material called urbanite.
Reuse is the action or practice of using an item, whether for its original purpose or to fulfill a different function. It should be distinguished from recycling, which is the breaking down of used items to make raw materials for the manufacture of new products. Reuse – by taking, but not reprocessing, previously used items – helps save time, money, energy and resources. In broader economic terms, it can make quality products available to people and organizations with limited means, while generating jobs and business activity that contribute to the economy.
Waste sorting is the process by which waste is separated into different elements. Waste sorting can occur manually at the household and collected through curbside collection schemes, or automatically separated in materials recovery facilities or mechanical biological treatment systems. Hand sorting was the first method used in the history of waste sorting. Until now this method is still used.
Upcycling, also known as creative reuse, is the process of transforming by-products, waste materials, useless, or unwanted products into new materials or products perceived to be of greater quality, such as artistic value or environmental value.
Sustainable packaging is the development and use of packaging which results in improved sustainability. This involves increased use of life cycle inventory (LCI) and life cycle assessment (LCA) to help guide the use of packaging which reduces the environmental impact and ecological footprint. It includes a look at the whole of the supply chain: from basic function, to marketing, and then through to end of life (LCA) and rebirth. Additionally, an eco-cost to value ratio can be useful The goals are to improve the long term viability and quality of life for humans and the longevity of natural ecosystems. Sustainable packaging must meet the functional and economic needs of the present without compromising the ability of future generations to meet their own needs. Sustainability is not necessarily an end state but is a continuing process of improvement.
Waste management in Japan today emphasizes not just the efficient and sanitary collection of waste, but also reduction in waste produced and recycling of waste when possible. This has been influenced by its history, particularly periods of significant economic expansion, as well as its geography as a mountainous country with limited space for landfills. Important forms of waste disposal include incineration, recycling and, to a smaller extent, landfills and land reclamation. Although Japan has made progress since the 1990s in reducing waste produced and encouraging recycling, there is still further progress to be made in reducing reliance on incinerators and the garbage sent to landfills. Challenges also exist in the processing of electronic waste and debris left after natural disasters.
Demolition waste is waste debris from destruction of buildings, roads, bridges, or other structures. Debris varies in composition, but the major components, by weight, in the US include concrete, wood products, asphalt shingles, brick and clay tile, steel, and drywall. There is the potential to recycle many elements of demolition waste.
Recycling can be carried out on various raw materials. Recycling is an important part of creating more sustainable economies, reducing the cost and environmental impact of raw materials. Not all materials are easily recycled, and processing recyclable into the correct waste stream requires considerable energy. Some particular manufactured goods are not easily separated, unless specially process therefore have unique product-based recycling processes.
Products made from a variety of materials can be recycled using a number of processes.
Hima Cement Limited (HCL) is a cement manufacturer in Uganda. It is a subsidiary of the Holcim Group, a building materials manufacturer headquartered in Switzerland, with subsidiaries in over 80 countries.
Veena Sahajwalla is an inventor and Professor of Materials Science in the Faculty of Science at UNSW Australia. She is the Director of the UNSW SM@RT Centre for Sustainable Materials Research and Technology and an Australian Research Council Laureate Fellow.
Globally, women are largely under-represented in STEM-related fields; this under-representation is especially prevalent in Africa where women represent less than 20% of the workforce in these fields. African women in engineering and STEM related fields are more susceptible to discrimination and to be devalued in African countries.Regardless of this lack of representation in STEM-related work, there are many important female engineers from across the continent. Furthermore, a number of organizations within and out of Africa are working towards minimizing the disparity within the workforce.
Packaging waste, the part of the waste that consists of packaging and packaging material, is a major part of the total global waste, and the major part of the packaging waste consists of single-use plastic food packaging, a hallmark of throwaway culture. Notable examples for which the need for regulation was recognized early, are "containers of liquids for human consumption", i.e. plastic bottles and the like. In Europe, the Germans top the list of packaging waste producers with more than 220 kilos of packaging per capita.
Waste light concrete (WLC) is a type of light weight concrete where the traditional construction aggregates are replaced by a mix of shredded waste materials and a special group of additives. Used in infrastructure and building construction.
Plastic sequestration is a means of plastic waste management that secures used plastic out of industry and out of the environment into reusable building blocks made by manual compaction. Plastic sequestration is motivated by environmental protection and modeled on the Earth's process of carbon sequestration. Emerging out of the struggle of towns and communities in the Global South to deal with plastic pollution, plastic sequestration compaction methods are characterized by being locally based, non-capital, non-industrial and low-tech. Plastic sequestration is defined by the goals of securing plastic out of the environment and out of high energy/carbon industrial systems. Based on eliminating the chemical and physical and abiotic and biotic degradation pathways, plastic sequestration aims to achieve these goals, by terminally reducing the net surface area of thin film plastics. The building blocks that emerge from plastic sequestration are used in applications that further protect from degradation and permanently keep plastic out of industrial processes, thereby preventing their carbon emissions.
