**1. Introduction**

*Spirulina* (*Arthrospira*) is a 3.6-billion-year-old cyanobacterium and inhabits alkaline aquatic ecosystems from freshwater to seawater [1, 2]. As sustainable primary producers, the cyanobacteria have been studied on various aspects centered by bio-industry and environmental

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

bioremediation [3–6]. *Spirulina* that highly contains various functional materials has been focused as an important nutrition source for the future of humans and animal feeds, so that related industry has been gradually growing [2, 7, 8, 12]. In addition, the biomass plays an important role in broad ranges of industries [9, 10] and functional foods using proteins [3, 11]. In particular, *S. platensis* has been mostly studied for industrial production, in which the most important factors for an increase of production could be nutrient concentration, light intensity, and optimal water temperature [12]. *Spirulina* sp. including other microalgae are cultured on a large scale worldwide for industrial use [13–17]. Proteins and phytopigments (phycocyanin and β-carotene) along with polyunsaturated fatty acids from *Spirulina* are one of the high value-added materials that bring health to humans [2, 13, 18].

From 2008, small-scale (laboratory to 1.5 ton) experiments have been conducted to investigate the biomass production combined with culture conditions and low-cost medium of *S. platensis* and *Spirulina maxima* in Korea [33, 39, 40], but further progress was not reported. In 2011, the first pilot-scale *Spirulina* plant with semi-open raceway ponds was established in Ansan [41]. The purpose of this chapter is to present for construction technology of BIM-based ORS allowing year-round culture in the environment with four seasons, so that an ORS was constructed in a glass greenhouse structure and a culture study was performed on a pilot scale

quality analyses on year-round batch culture of *S. maxima* that has a characteristic of strong

The city of Ansan was selected for the pilot study for production of *Spirulina*. Ansan is located in Western South Korea (37.287°N, 126.833°E), about 30 km south of Seoul, on the coast of the Yellow Sea. Recent average temperatures generally exceed 30°C in summer, and in winter are above −5°C. The average temperature is 12.5°C, and number of sunny days per year generally ranged from 86 to 124, with >10 h of sun per day for the whole year. Mean monthly temperatures are shown in **Figure 1A**. **Figure 1B** shows that weekly average solar radiation ranged

99 to 138, and average annual rainfall was about 1150 mm in the locality of the cultivation area.

**Figure 2** shows schematic processes for planning and construction of *Spirulina* culture system using BIM technology. A pilot system for microalgae production was constructed in the Korea Institute of Ocean Science and Technology based on BIM technology which analyzes atmospheric environment data (temperature, solar radiation, and shadow effect etc., **Figure 3**) of the past for a long time, and predicts the future based on the data in order to design an

**Figure 4A** is a vertical section of microalgae pilot system constructed based on BIM, in which the roof and side windows were designed with a maximal consideration of natural ventilation, and optimal construction cost and efficiency was realized by a four-way slide window at the side and the introduction of automatic opening and shutting system on the roof. **Figure 4B** is a horizontal section of the modified ORS culture facility. Each size of the culture facility was 10,000 (W) × 3250 (L) × 550 (H) mm, and the culture raceway was finished with concrete after vertical excavation of the ground as deep as 600 mm for the purpose of using geothermal heat as shown in **Figure 4**. Depth of medium for the culture was maintained as 400 mm. Boiler pipes were buried in the concrete floor of the modified ORS for maintenance of culture temperature in the winter. Computational fluid dynamics (CFD) was conducted to analyze and optimize the mixing (e.g., water flow and paddle rotational speed) of medium with *S. maxima* cells in the ORSs. The main purpose is to find the suitable rotational speed of the paddle to maximize mixing in the flow field.

. From 2006 to 2010, the number of rainy days per year ranged from

alkaline culture and on produced-dried biomass were performed at the same time.

**2. System construction and strategies for culture plan**

**2.2. Construction of culture system and its structure**

). In addition, in order to verify sustainability of the system, year-round biochemical

Cultivating *Spirulina maxima*: Innovative Approaches http://dx.doi.org/10.5772/intechopen.74265 63

(173.5 m2

**2.1. The production site**

from 1721 to 5671 Wh/m2

optimal eco-friendly structure.

Nowadays, microalgae are mostly cultured in photobioreactors (PBRs) and open raceway systems (ORSs) for industrial production [2, 19, 20]. Advantages of PBR include applicability of various designs in production, easy control of growth condition, prevention of biological contamination, and high productivity. On the contrary, it requires high expenses in initial investments, device maintenance, and expansion of mass production facility [20–22]. In contrast, ORS can directly use solar energy and CO2 in the air though it has a low aerial productivity than PBR, and it is also advantageous due to inexpensive materials for facility (PVC, FRP, concrete, plastic, and soil) and easy to scale up structure. In respect of commercialization, ORS needs a low initial investment cost, while it has a highly efficient productivity, so that ORS has been attracting more interest [15, 20, 23–30]. However, there are still steps that need to be taken for the commercialization of ORS, which includes a control of water temperature and light intensity depending on season, elevation of aerial productivity, development of highly efficient microalgae species, development of low cost and highly efficient culture medium, technology of contamination improvement, and establishment of protocol for year-round culture and harvest [19, 20, 31–33].

Culture conditions of microalgae in ORS and designing of system are closely related with environment of selected area. *Spirulina* was the most widely used in outdoor cultivation trials and interests for commercial production have been increasing in many places based on the studies of intensive ecological and physiological research and development over four decades. However, this cyanobacterium needs high temperatures for optimal growth, thus commercial production has been limited until subtropical areas. In temperate regions, high temperatures are recorded in summer season, while the temperature is certainly low in fall and winter seasons. The overall temperature range should not be a suitable range for *Spirulina* growth in a year. Consequently, little information of commercial production has been reported in temperate areas [32, 34, 35]. Thus, an environmental analysis needs to be carried out on selected area for a culture system with maximal productivity based on which culture system needs to be constructed. Recently, the concept of building information modeling (BIM) developed in construction field was first introduced by the National Institute of Standards and Technology (NIST) of the Department of Commerce in the USA in 2007. BIM refers to a recent construction process that analyzes data with 3D modeling method using big data and information of the past and then applies it from designing to installation process, avoiding existing 2-D design. Therefore, BIM technology is advantageous due to cost saving for installation operation and prediction of future [36–38]. As shown in success cases such as the Disney Concert Hall of the US, the Olympic Main Stadium of Beijing, and Melbourne Recital Center, BIM technology has emerged as an important issue in architectural industry, so that it is considered beneficial to apply it to a microalgae production facility.

From 2008, small-scale (laboratory to 1.5 ton) experiments have been conducted to investigate the biomass production combined with culture conditions and low-cost medium of *S. platensis* and *Spirulina maxima* in Korea [33, 39, 40], but further progress was not reported. In 2011, the first pilot-scale *Spirulina* plant with semi-open raceway ponds was established in Ansan [41]. The purpose of this chapter is to present for construction technology of BIM-based ORS allowing year-round culture in the environment with four seasons, so that an ORS was constructed in a glass greenhouse structure and a culture study was performed on a pilot scale (173.5 m2 ). In addition, in order to verify sustainability of the system, year-round biochemical quality analyses on year-round batch culture of *S. maxima* that has a characteristic of strong alkaline culture and on produced-dried biomass were performed at the same time.
