Management of small pig waste/wastewater in the tropics is considered as a rather difficult problem, especially in the land limited and populated areas. In order to eliminate the problem or difficulty in technology transfer, two bio-treatment processes, namely, modified hybrid anaerobic treatment (MHAT) and combined bio-fixed film and aquatic plant (CBFFAP), were investigated for the potential of developing a pre-fabricated package treatment plant for the application of a small pig wastewater. It was found that the MHAT process provides an effective treatment for high concentrated pig waste/wastewater. At a loading rate of 2.7-3.5 g TVS/L/day, a TVS removal efficiency of 59-80% and methane yield of 0.23-0.34 L/g TVS added can be achieved. Also, smaller amounts of digested effluent are discharged.
For the CBFFAP process, more than 90% of TCOD, 95% of TKN, and 99% of TSS can be removed in the pond in series system. Because it is simple in design and operation and low in maintenance, the two bio-treatment processes can be developed into a pre-fabricated plant for treating the small wastewater in the moderate land limited and tropical areas.