The recycling of waste sludge generated from plants for pig
wastewater treatment begins by reducing the water content. This
process is carried out either by solar drying ( Fig. 1) or by
using a pressing machine ( Fig. 2). The latter method uses less
labor and space than the former. During this process, the water
content falls from about 80 % to 10 %. The dried sludge is
further processed in a chamber for fermentation or composting
for 50 days ( Fig. 3). The final sludge product has the
following characteristics and nutrient content; pH 6.42;
electric conductivity (EC) 2.91 mS/cm; total nitrogen 4.19; P2O5
9.61; CaO 10.28; MgO 1.88; Zn 0.4; Cu 0.076; organic matter
content 65.9 %. As a Culture Medium: Pot tests for vegetables
showed that compost made from sludge could be used as a culture
medium instead of peat. The compost could also be used mixed
with bark and vermiculite. As an organic fertilizer In a trial
for Chinese cabbage, the application of composted sludge at a
rate of 40 mt/ha gave the same yield as