Enhancing SCP production from wastewater by controlling the CN ratio of the feed

• Main Author: Lim, Wei Xuan
• Other Authors: Stefan Wuertz
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2022
• Subjects: Engineering::Environmental engineering
• Online Access: https://hdl.handle.net/10356/163607
• Institution: Nanyang Technological University

SCP production is one of the methods derived to combat rising food demand in the future by providing alternative sources of amino acids for both human and animal consumption. By utilising community-based approaches to producing SCP, microbial community-cultures are more resilient to disruptions than axenic cultures and can produce protein used in fish food. Previous research indicates that a higher nitrogen content (Lower CN ratio) results in better protein production and yield. In this study, the CN ratio of the feed utilised in two reactors were altered by addition of ammonium sulphate and controlled at a fixed ratio of 10 and 20 for 32 days to find out if increasing the sTN affected SCP growth rate. Samples were taken on alternate days and experiments were conducted for solids and chemical analysis. Solid parameters such as TSS and VSS were tested while chemical parameters such as sCOD, sTN, DNA, amino acid composition and protein content of the solids were tested. Based on the amino acid composition and protein content, the SCP produced contained essential amino acids for animal and human consumption while the protein content was on the higher side at 60% when compared to other instances of SCP production. However, the sTN available was not being completely utilised resulting in large amounts of sTN being discharged thus more studies tested on the optimum CN ratio is recommended to optimise the nutrients utilisation.