Recycling of manure nutrients: use of algal biomass from dairy manure treatment as a slow release fertilizer

Agricultural nutrient surpluses as potential input sources to grow third generation biomass (microalgae): A review

“…The advantage of 40 biofuels over traditional fuels, include greater energy security, reduced environmental 41 impact, foreign exchange savings and socioeconomic benefits related to the rural 42 sector [4]. 43 …”

“…Algae utilise the N and P present, converting nutrients into biomass [43] The dried algae contained approximately 1.5-2% P and 5-7% N. [55] [106]; [107]) and atthe lower end of the range from research on naturally ventilated slatted sheds by 360 [108]. cattle and pig slurry and 75% of poultry slurry will be anaerobically digested.…”

Lipid Productivity of Algae Grown on Dairy Wastewater as a Possible Feedstock for Biodiesel

“…This use offers advantages over direct application of nutrient-rich wastewater, which may cause indirect runoff or contamination of ground water. Algae biomass degrades slowly thereby releasing nutrients slowly, which can improve plant uptake (Mulbry et al, 2005), although the timing of nutrient release may not be optimal for some crops.…”

Nutrient removal from an anaerobic membrane bioreactor effluent using microalgae. Study and modeling of the process.

“…Study and modeling of the process 6 and CO 2 which can also contain small amounts of H 2 , N 2, and H 2 S. It is a renewable energy source which can be used, for instance, in a gas engine to generate electricity and heat. The generated sludge can be used as slow-release fertilizer (Mulbry et al, 2005).…”

“…Study and modeling of the process 6 and CO 2 which can also contain small amounts of H 2 , N 2, and H 2 S. It is a renewable energy source which can be used, for instance, in a gas engine to generate electricity and heat. The generated sludge can be used as slow-release fertilizer (Mulbry et al, 2005).Apart from a lower energy demand (since no oxygen supply is needed) and biogas generation, anaerobic treatments present the following advantages versus aerobic treatments: i) reduced amount of sludge generation (up to ten times lower than in aerobic treatment according to Jeison, 2007), ii) high capacity to treat slowly degradable substances and iii) the possibility of nutrient recovery. On the other hand, anaerobic processes for wastewater treatment also present some disadvantages, such as i) the need to operate at high solids retention time or high temperatures (due to the slow growth of the anaerobic microorganisms), ii) the high sensitivity of the biomass to process overloads and iii) its low settleability, which involves operating with big reaction volumes.…”