Utilização de cinza de algaroba como matéria-prima alternativa para uso em blocos de solo-cal.

Abstract

The agreste region of Pernambuco state has the third largest clothing pole in Brazil, where one of the industrial stages uses the algaroba wood (prosopis juliflora) as an energy matrix for the production of hot water and steam, thus generating a high volume of waste in the form of ash. The objective of this work was to evaluate the incorporation of algaraba wood botton ash in blocks of soil-lime, because it is a constructive system that has simplicity in its production, and can be an alternative for the construction of social interest. The ashes were collected in a representative laundry of the clothing pole of Pernambuco state. The algaroba ashes were incorporated into the soil-lime blocks with proportion of 1:10 (lime / soil) in partial or total substitution of the commercial lime, in the proportions of 3, 5 and 7% per algarroba bottom ash (CBLA ) only sieved in ABNT No. 200 mesh (0.074mm) and in the proportions of 50%, 75% and 100% by lime of CBLA. After analyzing the results, it was verified that commercial lime substitution by up to 7% of CBLA and up to 100% CBLA lime is feasible, since blocks with substitution presented results similar to those obtained by standard blocks (without substitution) and according to the ABNT requirement. Afterwards, a beneficiation process was developed in which the ashes were sieved in ABNT mesh No. 200 (0.074mm), washed, calcined and hydrated, and produced lime from algaroba ash (CBLA lime). A process for the use of controlled temperature in the cure of soil-lime blocks was also developed in order to avoid that the average variations of 5°C at the ambient temperature of the place where the research was carried out compromised the accuracy of the results of mechanical resistance and water absorption of cured blocks at different times of the year.