Composting of Pineapple Residues and Food Waste: A Pilot-Scale Study
Nguyen, Thien M.
Lam, Nghiep C.
Le, Phung Thi Kim
Tran, Viet Tan
Nguyen, Nga T. T.
Hoang, Hoang A.

How to Cite

Nguyen T.M., Lam N.C., Le P.T.K., Tran V.T., Nguyen N.T.T., Hoang H.A., 2021, Composting of Pineapple Residues and Food Waste: A Pilot-Scale Study, Chemical Engineering Transactions, 83, 301-306.


Spraying herbicide, followed by burning, is a common practice for clearing pineapple residues (leaves and stems) and preparing subsequent cultivation crops in the Mekong Delta, Vietnam. This is an unsustainable agricultural practice that causes environmental pollution. In this study, pilot-scale pineapple residue composting was studied at Tan Phuoc district, Tien Giang province. Approximately 5.5 t of pineapple leaves and stems were mixed with 10 wt% food waste and 0.1 % v/w effective microorganisms. Chopped pineapple residues and food waste were distributed in layers in sequence and sprayed with the microorganism solution. Composting was carried out in a pyramid-shaped pile with a bottom diameter of approximately 5 m and a height of about 1.5 m. The composting temperatures were monitored daily using a digital thermometer. The composting mixture was withdrawn, mixed thoroughly and then re-distributed to the composting pile every 3 d. Composting was performed after 45 d when the composting pile temperature almost reached ambient temperature. The compost product was subjected to pH and mesophilic/thermophilic microorganism cell density measurements. Phytotoxicity tests were carried out, and other important parameters such as organic content, useful/harmful microorganisms and heavy metals were determined. Mesophilic and thermophilic microorganism densities were approximately 2 x 108 and 3.8 x 107 CFU/g. The compost pH was 7.3, and the organic matter content reached 32.3 wt%. Heavy metals and harmful microorganisms, such as E. coli and Salmonella, were also within Vietnamese standards. Root length and number of roots were 372.8 % and 22.6 % higher than controls; stem length and diameter were 137.5 mm and 15.1 mm, and were not significantly different from controls (p <0.05). The seed germination index of 141.56 was higher than the minimum value of 80 %, indicating that the compost was phytotoxic free and matured.