Unidade de produção agrícola irrigada com águas cinzas de lavanderia pública no semiárido paraibano.

Abstract

The semiarid region of northeastern Brazil is composed of 24.6 million people, making it the world's most populous semiarid (IBGE, 2010). This study aimed to deploy eight units of UP AC's agricultural production controlled using the gray waters of a communal laundry in the district of Ribeira de Cabaceiras, PB. The research was conducted in the premises of the public laundry Ribeira district, municipality Cabaceiras, PB, located in one of the driest regions of Brazil in the semi-arid region of Paraiba cariri. The uni^s of agricultural production subsidiaries were divided into four units with two batteries and four drive uninsured coverage which was made with plastic canvas and all units have area of 6m2. The plumbing greywater from the laundry room was designed in batches. The pH of the water sample from the well that supplies the public laundry got value 8.2, (basic) and compared with the values of the water tank (gray water gross) and the lowest of the four readings pH 6 was found, 06 gray water gross (before entering the units or tanks) as characterizing the acid pH. The storage for about 48 h leads to the decay of dissolved oxygen and consequently the aesthetic problems, as in the case of this work was that the water was "stored" within 8 units for 120 days and had to collect about 1 liter every 30 individual days observed that the drain water collected unit had dark color and strong odor, unlike the initial characteristics when entering the system and the values of dissolved oxygen were decreased approximately 55-95%. The percentage of leaves varied significantly (P <0.05), showing a linear trend for growing crops elephant grass and purple velvet bean, has the passion for culture, it is reasonably developed, one of the reasons that may have affected this limitation is due to the high electrical conductivity, thus high salinity and low pH. The waste water from the laundry at the end of the experiment showed the following characteristics: EC = 1.92 dS.m-1, pH = 7.31 and OD = 55.5 mg L - l . Greywater used had limitations on the growth of the culture of passion while the cultures of Mucuna black and purple elephant grass had their good growth and in terms of dry phytomass produced showed the greatest amount. The culture of velvet bean had greater growth in the cover treatment while the treatment without coverage promoted greater growth in the elephant grass than in the treatment without cover. The Agricultural Production Units Subsidiaries for the treatment of greywater resulted in a decrease in EC, pH and DO.