In general, to date, the majority of cultivated, dried biomass of Kappaphycus spp. has been used for the manufacture of refined (RC) or semi-refined carrageenan (SRC) on a commercial scale. However, the present study was focused on the production of SRC using wet fibrous residue left over after an agricultural bio-stimulant was extracted from the fresh biomass of Kappaphycus alvarezii in the manner of a biorefinery operation. The investigation examined the recovery ratio and quality of both bio-stimulant and SRC from the fresh biomass of K. alvarezii farmed on the Tamil coast of India for two consecutive seasons. This study was conducted on a large, pre-commercialization pilot-scale, i.e. 10.0 t of fresh biomass of K. alvarezii was crushed in each batch and a total 10 batches were made, each month during 2012 and 2013. The total recovery of the agricultural bio-stimulant and SRC from 1.0 t of fresh material processed at different seasons ranged from 19.58–23.69 dry kg (average 21.09 ± 1.35 kg) and 24.27–41.61 dry kg (average 31.75 ± 6.99 kg) respectively with a moisture content of 934.70–956.15 kg (average 947 ± 6.17 kg). The economics of conversion of fresh seaweed into agricultural bio-stimulant and SRC through MUZE (multi-stream, zero-effluent) process was far better as compared to conversion of dry weed into SRC alone through conventional methods, i.e. 1.0 t FS (Fresh seaweed) yielded a net profit of 224.14 US$ through multi- stream processing, whereas its dry-weed equivalent produced only 118.34 US$. The present investigation concluded that the fresh biomass of K. alvarezii can be used to co-produce agricultural bio-stimulants with a good efficacy and provide a relatively low yield of SRC with medium gel strength.