2. Furnace temperature of coffee grounds as organic waste-based cementitious material in concrete
Anisah, Maulody Nugroho, Santoso Sri Handoyo, Ririt Aprilin Sumarsono, Sittati Musalamah, Agphin Ramadhan, Kusno Adi Sambowo, Arris Maulana

Universitas Negeri Jakarta

Abstract

Organic waste results as a high impact as inorganic material to our environment which rise the alert to manage them seriously. For several years, the idea of recycling has been effective as the solution prominently in the construction and material field. Accordingly, this paper discusses the significance of organic waste-based material from the coffee powder utilized as the 5% cement replacement in concrete. Ultimately, the temperature variation of the muffle furnace to derive into coffee grounds is investigated chemically and mechanically to the compressive strength of concrete. Furnace temperature variation was set from 600°C up to 750°C for 2 hours which disclosed dominant potassium oxide. Else, some chemical components as found in cement was present except silicon oxide which predominantly appears in cement to increase concrete strength. The higher the temperature applied; the less proportion of chemical components resulted from. However, the chemical reaction between coffee grounds, cement and other matrices in concrete mixture generated better compressive performance in accordance with the furnace temperature climb reaching over 40 MPa which was above the targeted control sample. Even though the reactivity of the mixture was not detail observed, the coffee grounds ash obtained from 750°C furnace process was eligible as cement replacement in the concrete mixture.

Keywords: Furnace temperature, coffee grounds, compressive performance

Topic: Civil Engineering