System for producing bioethanol from algae

Abstract

A system for producing bioethanol from algae, comprising: (i) a body (23) made of a foam board, configured to hold a fermentation substrate and yeast intended for the production of bioethanol; (ii) a plurality of impellers (20) embedded in the body (23), the impellers (20) rotating to mix the fermentation substrate and yeast uniformly; (iii) a pair of sensors (21) for monitoring the temperature inside the body (23) during the mixing of the fermentation substrate and yeast; (iv) a digital temperature display (21) projected onto the body (23) to show the monitored temperature and to notify a user regarding temperature control;(v) a motorized plywood shaft (22) arranged inside (23) to ensure continuous movement of the substrate and yeast to guarantee uniform nutrient and gas distribution and to mimic natural water currents; and (vi) a cooling fan (24) arranged on the bioreactor, rotating about its axis to maintain the internal temperature and thereby support the production of highly efficient bioethanol.

Description

TECHNICAL FIELD OF THE INVENTIONThe present invention relates to a system for producing bioethanol from algae, in particular macro- and microalgae from fresh water and seawater, for the lasting and controlled production of bioethanol, in particular biodiesel.BACKGROUND OF THE INVENTIONThe population growth in the last century has resulted in an increase in worldwide energy consumption. In order to meet the increased energy demand, crude oil has been used as the most important resource. World oil production would decrease from about 25 billion barrel to 5 billion barrel. Because of this inevitable depletion of world-wide petroleum resources in the coming years, interest is paid world-wide to search for alternative, non-petroleum-based energy sources. One of the best alternative fuels to seriously overcome energy crisis is bioethanol. Energy is obtained from biomass by biological carbon fixation. Various factors such as the need to increase energy safety and increases, as well as increasing scientific and public attention to biomass are being driven.In industrial and developing countries, the need for bioethanol / biodiesel has become a serious problem in the last century, and thus the production of bioethanol is of greatest importance. The cost of ethanol production, however, depends on the fermentation process, the optimum fermentation conditions and environmental factors.Existing bioreactor systems often have problems with insufficient distribution of fermentation substrate, insufficient pH and temperature control, and insufficient uniform agitation. The lack of uniformity of these systems reduces productivity and increases operating costs. Maintaining optimum conditions such as temperature, pH and substrate distribution enhances ethanol production in a short time.US20200172939A1 describes a low cost method for making lignocellulosic biomass accessible to cellulase enzymes and producing fermentable sugars. Some variants provide a method for producing ethanol from lignocellulosic biomass (such as sugarcane bagasse or corn stalks) comprising introducing a lignocellulosic biomass feedstock into a single stage fermenter, exposing the feedstock to a reaction solution of steam or liquid hot water in the fermenter to solubilize the hemicellulose in a liquid phase and provide a cellulosic solid phase, refining the cellulosic solid phase together with the liquid phase in a mechanical refiner to provide a mixture of refined cellulosic solid solids and the liquid phase, enzymatically hydrolyzing the mixture in a hydrolysis reactor with cellulase enzymes to produce fermentable sugars, and fermenting the fermentable sugars to produce ethanol. Many alternative process configurations are described. The disclosed processes may be used for other fermentation products.US10927388B2 describes a process for producing bioethanol from lignocellulosic biomass. The method of the present invention is capable of: minimizing the impurity content of an enzymatic saccharification raw material by extracting the biomass before the pretreatment with hot water and removing extractables such as inorganic salts; substantially suppressing the production of excessive sugar decomposition products by pretreating the biomass from which the hot water extractables have been removed under conditions for maximizing the xylan yield; producing fermentable sugar at low cost without washing a pretreated solid obtained from a subsequent solid-liquid separation but only by concentrating a sugar solution obtained after the enzymatic saccharification (acid hydrolysis) using a separation film; and producing bioethanol therefrom in high yield.From the above cited documents it is evident that the existing systems are inefficient and lack monitoring and regulating the internal environmental conditions in the bioreactor. In addition, they combat inefficient distribution of the fermentation substrate, insufficient control of pH and temperature, and uniform agitation. Moreover, they use enzymatic methods which are relatively expensive.In order to overcome the above-mentioned problems, an efficient and cost-effective system is required with which the bioethanol production from macroalgae and microalgae can be increased.Objects of the InventionThe main object of the present invention is to develop a low cost and efficient system for the production of ethanol from fresh water and marine macro and micro algae suitable for biodiesel production.Another object of the present invention is to develop a system that is energy efficient and scalable, making the system adaptable for laboratory research and larger industrial applications.Another object of the present invention is to develop systems which constantly provide light to maintain the temperature required for fermentation.Another object of the present invention is to develop a system that is light weight, portable, and durable, and provides a practical and scalable solution for bioethanol production, thereby reducing process costs and complexity.SUMMARY OF THE INVENTIONThe present invention discloses a system for producing bioethanol from macro and micro algae in fresh and seawater, comprising a system for producing bioethanol comprising an elongated body of a foam plate for storing a fermentation substrate comprising micro and macro algae and yeast for producing bioethanol, a plurality of impellers embedded in the body, the impellers rotating to uniformly mix the fermentation substrate and the yeast, a pair of sensors (cooling and heating) for monitoring the temperature in the body during mixing of the fermentation substrate and the yeast, a digital temperature display mounted on the body for displaying the monitored temperature to notify a user of the temperature control, a motorized plywood shaft in the body for continuous movement of the substrate and yeast for uniform nutrient and gas distribution and for mimicry of natural water flows, and a cooling fan mounted on the bioreactor and rotating about its axis to maintain the internal temperature and thus contribute to the production of high efficiency bioethanol.The system also comprises the body equipped with a direct current (DC) motor that supplies power to the impellers to rotate continuously and mix the fermentation substrate and yeast, a plurality of knobs for controlling and regulating motor function, a cooling fan, and a pair of sensors including a cooling and a heating sensor. By phytochemical studies, carbohydrate, lipid and protein content were determined using standard methods. Carbohydrates were extracted by acid hydrolysis with concentrated sulfuric acid followed by filtration to separate the algal substrate. The resulting fermentation substrate is inoculated in an individually developed bioreactor with Saccharomyces cerevisiaeand yeast extract-potato-dextrose (YEPD) medium and maintained under controlled conditions: 30°C temperature, pH 5.5 and agitation at 65 U / min. After a fermentation time of 15 days, the ethanol yield was between 14% and 16% (w / v).BRIEF DESCRIPTION OF THE DRAWINGSThe accompanying flowcharts and drawings are provided for enhancement of understanding of the present disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate an exemplary block diagram of the present disclosure method and, together with the description, serve to explain the principles of the present disclosure. Figure 1 is an isometric view of a system for bioethanol production. FIG. 2 shows a rear view of the bioethanol production system.DETAILED DESCRIPTIONA system for producing bioethanol from algae consists of an antifoam inlet, a steam inlet, a nutrient or inoculum inlet, a sterile nutrient medium inlet, an impeller, a cooling jacket, a cold water inlet, a crop tube, a pH probe, a temperature probe, a cold water outlet, a filtered exhaust outlet, pressure gauges, a motor, and an acid-base inlet.Antifoam inlet: Antifoam inlets are configured for the introduction of antifoam agents which are critical in the system to control and prevent the formation of excess foam. The choice of antifoam will depend on several factors including the type of cells or microorganisms to be cultured, the specific bioreactor design and downstream processing requirements. It is important to select an antifoam agent which is effective, nontoxic to the cells and compatible with the overall bioprocess.Steam inlet: The steam inlet plays a decisive role in the system, especially in sterilization. Steam is essential in bioreactor operations to maintain a sterile environment which is of fundamental importance for successful bioprocesses.Nutrient or Inoculum Inlet: Nutrients and inoculum are discharged into the bioreactor system via the inlet. Nutrients are the essential building blocks for the growth and metabolism of the cells or microorganisms in the bioreactor. They provide the necessary elements such as carbon, nitrogen, vitamins and minerals required for cell growth, cell maintenance and product formation. The inoculum is the population of desired cells or microorganisms that are introduced into the sterile nutrient medium in the bioreactor.Inlet for sterile nutrient medium: The sterile nutrient medium is the system's life blood. It is the carefully designed environment that provides all the cells need to grow, function, and produce the desired product. Without a properly prepared and sterile medium, the bioprocess will likely fail.Impeller: The main object of the impeller is to create a well mixed environment. This ensures that the nutrients are distributed uniformly so that all cells have access to the required resources, that the temperature is uniform throughout the vessel so that hot or cold spots which could damage cells are avoided and that oxygen (for aerobic organisms) is easily available to all cells.Cooling jacket: The cooling jacket is an important component for maintaining the precise temperature required for a successful bioprocess. It provides optimal conditions for cell growth, metabolism and product formation and ultimately contributes to the overall efficiency and effectiveness of bioreactor operation.Cold water inlet: The cold water inlet is of decisive importance for the temperature control system. It is the cooling source that allows precise control of bioreactor temperature and provides optimum conditions for cell growth and productivity.Sampling tube: The sampling tube is responsible for sampling the culture from the bioreactor, whether it be it for collecting the end product or for sampling during the bioprocess. It plays a decisive role for the overall efficiency and success of the bioprocess.pH probe: The pH probe is an important tool for monitoring and controlling pH. It helps maintain optimal conditions for cell growth and productivity, thus ensuring the success of the bioprocess.Temperature probe: The temperature probe is an important component for monitoring and controlling the temperature. It helps maintain optimal conditions for cell growth and productivity, thus ensuring the success of the bioprocess.Cold water outlet: The cold water outlet is a decisive part of the temperature control system. It allows the continuous circulation of the coolant and ensures that the heat is effectively removed from the bioreactor and the temperature remains optimum for the bioprocess.Filtered Exhaust Gases: Filtered exhaust gases are important to avoid contaminants, control odors, and protect the environment. They play a decisive role in ensuring the safety and sustainability of bioprocesses.Motor: The motor is essential for driving the impeller and ensuring proper mixing in the system. It plays a decisive role in the maintenance of a homogeneous environment and the optimization of the conditions for cell growth and productivity.Acid-base feed: Acids and bases are important tools for maintaining optimum pH. They allow precise control of the pH environment and ensure that the cells or microorganisms can grow and efficiently produce the desired products.The present invention provides a bioreactor system, in particular a bioreactor system specifically developed for the production of biodiesel (ethanol) from macro and micro algae from fresh water or seawater.Figures 1 and 2 show an isometric view and a rear view of the system for producing bioethanol from algae. The system presented here is an elongate body with suitable devices for aeration, agitation, temperature and pH control and outflow or overflow opening for removing the waste biomass of the cultured microorganisms together with their products. The system provides agitation (for mixing cells and medium), aeration (aerobic fermenter), O2 supply, regulation of factors such as temperature, pH, pressure, aeration, nutrient supply and liquid level, sterilization and sterility maintenance, and cell / medium extraction.They consist of various elements such as an agitator, an oxygen supply system, a foam control system and a variety of other systems such as a temperature and pH control system, sampling ports, a cleaning and sterilizing system, and conduits for filling and emptying the reactor. The system of the present invention therefore focuses on increasing the efficiency of ethanol production from algae and shortening the duration of the fermentation period by controlling and monitoring all internal environmental conditions of the bioreactor.The system for producing bioethanol from algae consists of an elongated body (23) made of a foam sheet configured to hold a fermentation substrate and yeast for producing bioethanol. The foam sheet used herein is corrosion resistant, adds no toxic substances to the fermentation medium, tolerates the steam sterilization process, and is capable of withstanding high pressure and withstanding pH changes. The size of the body (23) used here may vary according to the user's need. Its lightweight and durable foam panel construction makes it portable, easy to use, and adaptable to various environments so that it can be used in both laboratory research and industrial applications.Another important renewable energy source is the recovery of energy from biomass. These fuels are mainly produced from biological organic substance derived from plants, algae, microbial organisms and their wastes including dead organisms. Ethanol or bioethanol (C2H5OH) is often mixed with petroleum products and used for shipping purposes, which lowers costs as well as environmental pollution. Ethanol is one of the environmentally friendly fuels that can be produced by both chemical and biological processes. Algae are used to produce bioethanol from the fermentation of algal polysaccharides (starch, cellulose and other unique polysaccharides that occur in them). Algae are simple organisms that contain chlorophyll and use sunlight, carbon dioxide and other nutrients to produce bioethanol for photosynthetic purposes. Phototrophic algae convert carbon dioxide in the atmosphere to produce food in the form of carbohydrates, cellulose and starch, protein and lipids. For microalgae, their carbohydrate content (mainly starch) reaches up to 70% under certain conditions.The body (23) used here may be designed for small-scale fermenters and some for large-scale industrial applications, from the microbial cell (a few mm3) via shake flasks (100-1000 ml) to the laboratory-scale fermenter (1-501) and pilot scale (0.3-10 m3) to the large-volume plant scale (2-500 m3). The size of the mold sheet used here is 8 mm, which is a light, durable and cost-effective solution for experimental applications.Moreover, the capacity of the body (23) is 5 liters for storing the fermentation substrate for ethanol production. This construction ensures optimum conditions for fermentation in terms of temperature, pH, movement and a sensor pair (21) comprising cooling and heating sensors for controlling the whole fermentation process.Further, the plurality of impellers (20) are embedded in the body (23), the impellers (20) rotating to uniformly mix the fermentation substrate and the yeast. The stirrers (20) used herein are preferably three stirrers (20) mounted in the middle of the body (23) to uniformly mix the fermentation substrate and yeast for ethanol production. (Height -10.5 cm). The three stirrers (20) are mounted in the middle of the bioreactor and rotate at a speed of 25, 50 and 65 U / min (revolutions per minute) to uniformly mix the fermentation substrate and the yeast (Saccharomyces cerevisiae).Moreover, there are a pair of sensors (21) for monitoring the temperature in the body (23) during the mixing of the fermentation substrate and the yeast. The sensors (21) used here are cooling and heating sensors. The cooling and heating sensors provide stable conditions which are critical for an optimum fermentation rate. Moreover, a digital temperature indicator (21) is mounted on the body (23) to indicate the monitored temperature and inform the user of the control of the temperature.The body (23) used here is equipped with a motorized plywood shaft (22) of 12 mm diameter and 81 cm length, which is attached to the underside of the model to facilitate the forward and rearward movement of the bottles [bioreactor]. This movement mimics the natural water movement and promotes the uniform distribution of fermentation substrate and yeast as well as fermentation culture media. The fermentation time is 15 days in order to achieve maximum production of ethanol from algae. This innovative design significantly reduces the costs and time required for producing ethanol from algae.An 18 cm high foam plate box provides additional structural support and the stability and functionality of the photobioreactor for optimal microalga cultivation is further improved.A cooling means (24) is also mounted on the bioreactor and rotates about its axis to maintain the internal temperature and thus assist in the production of high efficiency bioethanol. The body (23) is also equipped with a direct current (DC) motor which supplies current to the impellers (20) so that they can rotate continuously and mix the fermentation substrate and the yeast. A 12-volt DC motor at 60 U / min is mounted behind the bioreactor to ensure continuous rotational movement. Also mounted behind the bioreactor is a 12-volt DC adapter for converting AC power to DC power.Moreover, the body (23) is provided with a plurality of knobs (25), preferably three knobs (25), for regulating the function of the motor, the cooling fan (24) and the sensor pair (21). Moreover, the body (23) is equipped with a light emitting diode (LED) having lumens and a warm white color essential for the fermentation process. These lights are positioned to ensure uniform illumination in the bioreactor and ensure that the entire fermentation process is run under optimum conditions.Thus, the present invention provides a cost effective platform for enhancing ethanol production from algae. By minimizing the construction costs of the bioreactor and improving the environmental control, the bioreactor ensures a higher ethanol yield with a simultaneous reduction in the operating costs, whereby biodiesel production becomes more economical and more sustainable.In one embodiment of the present invention, phytochemical analysis of the characterized algae was carried out using standard methods for the determination of carbohydrates, lipids and proteins. Carbohydrates were extracted from macro- and microalgae by acid hydrolysis with concentrated sulfuric acid and filtration was performed to separate the algal substrate. The fermentation substrate was inoculated into a designed bioreactor together with yeast ( Saccharomyces cerevisiae) and YEPD (yeast extract-potato-dextrose medium) under controlled conditions such as 30°C temperature, 5.5 pH, stirring speed 65 U / min, while the motorized stirring system ensures uniform mixing of substrate and Saccharomyces cerevisiae, which increases the efficiency of ethanol production. To better mix fermentation and yeast powder, a wood shaft (22) was attached below the bioreactor with a motor for continuous forward and backward movement. The fermentation time for maximum ethanol production from algae is 15 days. Thus, the present invention substantially reduces the cost and time required for producing bioethanol, preferably algae biodiesel. After 15 days, bioethanol production ranged from 14 to 16% by volume.Therefore, the present invention provides a low cost platform for enhancing the production of bioethanol from algae. By minimizing the construction cost of the system and improving environmental control, the system ensures a higher bioethanol yield while reducing the running cost, thereby making the production of bioethanol, preferably biodiesel, more economical and durable.Moreover, the system is light, long-lived and portable, requires only low capital investment and less maintenance, requires extracts from each of a micro- and macroalgae species for ethanol production, has a lower risk of contamination by fungi and bacteria, and also has an automatic temperature control system.References included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedUS 20200172939A1

[0005] US 10927388B2

[0006]

Claims

A system for producing bioethanol from algae, comprising: (i) a body (23) made of a foam sheet configured to store a fermentation substrate and yeast intended for producing bioethanol; (ii) a plurality of impellers (20) embedded in the body (23), the impellers (20) rotating to uniformly mix the fermentation substrate and the yeast; (iii) a pair of sensors (21) for monitoring the temperature within the body (23) during mixing of the fermentation substrate and the yeast; (iv) a digital temperature indicator (21) mapped to the body (23) to indicate the monitored temperature and notify a user of the control of the temperature; (v) a motorized plywood shaft (22) disposed within (23) to provide continuous movement of the substrate and yeast to provide uniform nutrient and gas distribution and mimic natural water flows; and (vi) a cooling fan (24) disposed on the bioreactor which rotates about its axis to maintain the internal temperature and thereby assist in the production of high efficiency bioethanol.The system according to claim 1, wherein the body (23) is equipped with a direct current motor (DC) that energizes the impellers (20) to rotate continuously and mix the fermentation substrate and the yeast.The system according to claim 1, wherein the body (23) is provided with a plurality of knobs (25) for regulating the function of the motor, the cooling fan and the sensor pair (21).The system of claim 1, wherein the fermentation substrate is a microalgae or a macroalgae.The system of claim 1, wherein the sensor pair (21) is a cooling and a heating sensor.

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