Valorization of agro-industry residues in the building and environmental sector: A review

Abstract

Environmental pollution has become a relevant issue as the population rises and resources decrease. Reuse and recycling still have the greatest potential as they turn the waste into a new resource, representing the ‘closed-loop’ step of a circular economy (CE). Looking for new applications for agro-industry waste represents both an environmental issue, as its incorrect disposal is a cause of pollution, and a chance to exploit zero-cost natural wastes. The present review, with around 200 articles examined, focuses on possible reuses of these residues in (a) building construction, as additives to produce thermal and acoustic insulation panels, and (b) in water treatments, exploited for removal of pollutants. The selected materials (coconut, coffee, corn, cotton and rice) have industry production wastes with suitable applications in both sectors and huge worldwide availability; their reuse may thus represent a new resource, with an impact based on the production rate and the possible replacement of current inorganic materials. Along with possible implementation of the selected materials in the building industry and environmental engineering, a brief description of the production and supply chain are provided.

Horizontal Flow Constructed Wetland for Greywater Treatment and Reuse: An Experimental Case

“…The EU adopted an ambitious Waste Circular Economy Package [24][25][26] in order to promote the reuse, recycling and recovery of raw materials to minimize the consumption of new resources [27,28]. WW can be considered a valuable resource that can help to overcome the water scarcity problem, especially in arid and semiarid climatic zones [29][30][31].…”

Extraction and Purification of Phosphorus from the Ashes of Incinerated Biological Sewage Sludge

“…This is essential for the development of crops [9] and is extremely important, especially in territories such as the Mediterranean area (e.g., Spain, Portugal, and Italy), where soil organic matter and nutrient depletion has reached worrying levels [10,11]. Other forms of material recovery, currently a minority in Europe, concern reuse in the construction sector (e.g., bricks and cement production and road construction) [12][13][14] and as adsorbent materials [15].…”

The Production of Sustainable Concrete with the Use of Alternative Aggregates: A Review

“…The integration of alternative materials help both saving natural resources and reducing waste disposal by incorporating urban and industrial wastes into concrete, according to the concept of circular economy [14]. The evaluation of the environmental benefits led by the use of recycled materials in common building elements is usually carried out by a Life Cycle Assessment in terms of primary embodied energy and greenhouse gas emissions, considering a "cradle-to-gate" approach [15].…”