Biocar ash emerging as a solid by-product from updraft fixed-bed gasification reactor and production of activated carbon from biocar ash and using it as an adsorbent agent

Abstract

The invention relates to the use of biochar ash, which is a solid by-product of an updraft fixed bed gasification reactor, and the activated carbon produced from this biochar ash as an adsorbent material. Said adsorbent material has use in the removal of colour from water and purification of pollutants of biochar formed as a solid by-product during the processing of organic wastes by the gasification process, as opposed to high-cost wastewater treatment processes, and of the adsorbent material obtained from biochar.

Description

[0001] BIOCAR ASH EMERGING AS A SOLID BY-PRODUCT FROM UPDRAFT FIXED- BED GASIFICATION REACTOR AND PRODUCTION OF ACTIVATED CARBON FROM BIOCAR ASH AND USING IT AS AN ADSORBENT AGENT

[0002] Technical Field of the Invention

[0003] The invention relates to using biochar ash, a solid by-product of an updraft fixed bed gasification reactor, and the activated carbon produced from this biochar ash as an adsorbent material. The adsorbent material made from the biochar ash, which is the subject of the invention, has applications in areas such as environmental engineering, environmental technology, renewable energy technologies, gasification, beneficial use of solid by-products as adsorbents, and obtaining high value-added products from biomass.

[0004] State of the Art

[0005] Wastewater occurs as any rainwater flow, industrial, domestic, or commercial wastewater or any combination of these carried by water. Wastewater carries microorganisms that cause many diseases and continues to produce microorganisms logarithmically during the waiting phase. Wastewater can also contain harmful chemicals and heavy metals. Therefore, wastewater-related diseases cause various environmental and health problems. The methods applied in wastewater treatment and removal of colour from wastewater require high costs. In chemical treatment methods such as coagulation-flocculation applied to textile industry wastewater, high disposal costs occur due to high amounts of chemicals and the hazardous properties of the chemical sludge formed. Wastewater with harmful content nature is released due to the colors contained in the water used in the production of textile products after production. One of the pollutants in wastewater is methylene blue. This pollutant, which is a cationic dye, is difficult to biodegrade. However, since it is not possible to release wastewater into nature without treatment, the pollutants in it must be removed.

[0006] Various physical-chemical and biological processes are used to remove pollutants from industrial wastewater before it is released into the environment. When adsorbed substances such as heavy metals and ionic dyes are in low concentration in wastewater, traditional treatment processes such as chemical precipitation and coagulation are low-effective and expensive

[0001] .

[0007] Membranes can be used in the treatment of wastewater. The most important problem encountered in systems using membranes is membrane clogging. In addition, the initial investment and operating costs of systems using membranes are high. In addition, there are systems using ozone in wastewater treatment. With the use of ozone, both viruses and bacteria in wastewater can be killed and all microorganisms and toxins can be oxidised. Ozone is an allotropic form of oxygen and a special oxidising agent. Ozone is a light blue coloured, strong smelling, unstable gas. For this reason, ozone should be manufactured when used. Ozone is used not only as a disinfectant but also as an oxidising agent to remove the colour and odour of water and its operating cost is also high. Activated carbon adsorption can also be preferred in wastewater treatment. Activated carbon adsorption is the process that uses activated carbon in powder or granular form to retain unwanted taste, odour, colour, trihalomethane, some organic compounds, humic acid and organic substances in water. Activated carbon is obtained by subjecting natural materials such as coconut shells, wood, and coal to high heat treatment in an oxygen-free environment and has a porous structure. The pollutants in the water that are to be removed are adsorbed into these pores and held. The contact time of water with activated carbon is very important in the adsorption process and is operated with an average contact time of 4 minutes. The pores of the activated carbon filling material become clogged over time and a backwash process with water and air must be performed to remove this blockage. In addition, since activated carbon filters with a porous structure create a suitable environment for bacterial growth, this material must be replaced every 1 -2 years on average. Considering the depletion of fossil fuel reserves and the environmental damage caused by their use, biomass is an important carbon neutral fuel source for obtaining energy. The gasification process is a thermochemical conversion method that provides energy and material recovery from biomass.

[0008] In the state of the art, various methods are applied to remove dye from wastewater, including coagulation-flocculation, membrane separation, ion exchange, chemical oxidation, electrochemical techniques and photocatalysis. However, these methods are more expensive and difficult to operate than the adsorption method in terms of cost-benefit. Therefore, the problems caused by the expensiveness and difficulty of operation of adsorption methods used in wastewater treatment cannot be prevented.

[0009] In another practice in the state of the art, among various physical and chemical methods, adsorption methods containing chemical adsorbents are preferred due to their easy design and performance. However, due to the properties of the adsorbent material and the fact that the adsorbent is mostly supplied from abroad, these applications are also economically limited. In this case, the problem of high costs cannot be prevented due to the supply of adsorbent materials used in wastewater treatment from abroad.

[0010] In another practice in the state of the art, resins are used to replace one ion with another ion in the ion exchange method used in wastewater treatment. In this method, regeneration must be done when the resin capacity is exhausted. The costs of the regeneration processes to be applied after the capacity and life of the resin used in the ion exchange method are high. Although ion exchange resins are introduced as effective commercial adsorbent in the treatment of industrial wastewater, their high cost prevents their effective use [2], In this case, in the method where resins are used for ion exchange in wastewater treatment, the cost problems arising from the regeneration processes to be applied after the capacity and life of the resin expires cannot be prevented.

[0011] Due to the reasons such as the limitations and inadequacies of the solutions in the state of the art, the economic limitations of these applications due to the fact that the adsorbent materials used in wastewater treatment are mostly supplied from abroad, the high cost of the chemicals used in wastewater treatment, the cost problems arising from the regeneration processes to be applied after the capacity and life of the resin expires in cases where ion resins are used, and the cost increase problem arising from expensive and difficult to operate adsorption methods, have made it necessary to make a development in this area. Brief Description and Aims of the Invention

[0012] The invention relates to the use of biochar ash, which is a solid by-product of an updraft fixed bed gasification reactor, and the activated carbon produced from this biochar ash as an adsorbent material. The types of adsorbent materials produced with said method show high performance in colour removal from aqueous solutions. By means of said method, adsorbent materials are produced to remove colour from textile wastewater and coloured waters.

[0013] One aim of the invention is to ensure the reuse of waste organic materials in wastewater treatment. In said method, by producing adsorbent material from biochar, which is a solid by-product obtained as a result of the gasification process, waste organic materials are reused in wastewater treatment.

[0014] Another aim of the invention is to develop materials with high adsorption capacity. With said method, biochar coming out of the gasification facility is converted into activated carbon, thus turning it into a material with high added value that is beneficial to the economy, and its adsorption capacities are increased.

[0015] Another aim of the invention is to reduce the use of extra chemicals used for colour removal in wastewater. With said method, the use of extra chemicals is reduced by converting biochar coming out of the gasification facility into activated carbon and using it for colour removal in wastewater. In addition, by using the activated carbon produced with said method as an adsorbent, colour removal in methylene blue solution can be achieved.

[0016] Another aim of the invention is to reduce the treatment costs in wastewater. The use of the adsorbent obtained from said biochar in the pre-treatment of the wastewater of a textile factory helps to reduce the pollutant load in organised industrial area wastewater treatment facilities and to ensure standard values. Thus, said adsorbent is effective in reducing treatment costs in both indirect and direct wastewater.

[0017] Another aim of the invention is to ensure that existing valuable wastes are transformed in a way that is beneficial to the environment and humans based on the zero waste principle. With the production of the adsorbent material that is the subject of the invention, it is possible to evaluate the wastes that many industrial establishments are obliged to dispose of in relation to biodegradable waste production. It is aimed to use the activated carbon produced with the biochar ash coming out of this updraft fixed bed gasification reactor as an adsorbent material especially in textile wastewater, to minimise the cost problems arising from the use of chemicals in wastewater treatment and to ensure the reuse of waste organic materials in wastewater treatment.

[0018] Detailed Description of the Invention

[0019] The invention relates to the use of biochar ash, which is a solid by-product of an updraft fixed bed gasification reactor, and the activated carbon produced from this biochar ash as an adsorbent material. The activated carbon obtained from biochar formed as a solid by-product during the processing of organic wastes, which is the subject of the invention, has use in the removal of colour from water and the purification of pollutants. The production of the adsorbent material, which is the subject of the invention, enables the evaluation of sludge, agricultural wastes and wastes with high biodegradable carbon content originating from treatment plants. In the method that is the subject of the invention, the method of obtaining activated carbon from biochar, which is the solid product obtained as a result of the gasification process, and their effectiveness in the removal of colour in methylene blue solution as an adsorbent material are explained. The types of adsorbent materials produced with said method show high performance in colour removal from aqueous solutions. By means of said method, adsorbent materials are produced to remove colour from textile wastewater and coloured waters.

[0020] The method for obtaining biochar ash as a solid by-product from an updraft fixed bed gasification reactor, which is the subject of the invention, comprises the process steps of: i. gasification of olive pomace, green waste, sewage sludge or the biomass as a mixture thereof in a fixed bed updraft gasification reactor, and ii. obtaining biochar ash from biomass after gasification.

[0021] Dry air and pure oxygen are used as gasification agents in a fixed bed updraft gasification reactor for the production of the adsorbent substance of the invention. In one embodiment of the invention, 0.05 L / min dry air and 0.05 L / min pure oxygen are used as gasification agents in a fixed bed updraft gasification reactor for the production of the adsorbent substance.

[0022] In another embodiment of the invention, 0.1 L / min dry air and 0.05 L / min pure oxygen are used as gasification agents in a fixed bed updraft gasification reactor for the production of the adsorbent substance.

[0023] In another embodiment of the invention, 0.2 L / min dry air and 0.05 L / min pure oxygen are used as gasification agents in a fixed bed updraft gasification reactor for the production of the adsorbent substance.

[0024] In another embodiment of the invention, 0.4 L / min dry air and 0.05 L / min pure oxygen are used as gasification agents in a fixed bed updraft gasification reactor for the production of the adsorbent substance.

[0025] In one embodiment of the invention, the gasification temperature of the fixed bed updraft gasification reactor used for the production of the adsorbent material is 700°C.

[0026] In one embodiment of the invention, the gasification temperature of the fixed bed updraft gasification reactor used for the production of the adsorbent material is 800°C.

[0027] In one embodiment of the invention, the gasification temperature of the fixed bed updraft gasification reactor used for the production of the adsorbent material is 900°C.

[0028] The production method of activated carbon from biochar ash to be used as adsorbent material, which is the subject of the invention, comprises the process steps of: i. weighing biochar ash samples, ii. mixing with phosphoric acid (H3PO4) and waiting, iii. carbonizing the resulting mixture by burning in the furnace, iv. washing with pure water to remove product impurities, and then drying in a drying oven. In one embodiment of the invention, the production method of activated carbon from biochar ash to be used as adsorbent material, which is the subject of the invention, comprises the process steps of: i. weighing biochar ash samples as 75 grams, ii. mixing with 41 .67 mL phosphoric acid (H3PO4) at a rate of 1 g / g and waiting for 30 minutes, iii. carbonizing the resulting mixture by burning in the furnace at 600 °C for 1 hour with a heating rate of 5 °C / min, iv. washing with pure water to remove product impurities, and then drying in a drying oven at 100 °C.

[0029] In the production method studies of the adsorbent material, which is the subject of the invention, gasification studies of olive pomace, green waste, sewage sludge and the mixture of these in the biomass sample were carried out in the updraft gasification reactor. Biochar ash with different properties was obtained from 4 different biomass. 4 different activated carbons were obtained from these biochar ash samples with different processes. Their efficiency and effects on colour removal were determined. It was determined that these materials have strong adsorbent material properties. A fixed bed updraft gasification reactor is used for the production of said adsorbent material. Green waste, sewage sludge, olive pomace or a mixture of these are used as biomass in the gasification reactor. The amount of biomass was used as 75 g in each gasification experiment. After each gasification experiment, 20-40 g of biochar was obtained depending on the sample used.

[0030] REFERENCES

[0031] [1] Crini, G., 2006. Non-conventional low-cost adsorbents for dye removal: a review. Bioresource Technology, 9 (7), 1061 -1085.

[0032] [2] Vijayarakhavan, K. and Yun, Y.-S. 2008. Bacterial biosorbents and biosorption. Biotechnology Advances, 26, 266-291 .

Claims

CLAIMS1. The production method of biochar ash as a solid by-product from an updraft fixed bed gasification reactor comprises the process steps of: i. gasification of olive pomace, green waste, sewage sludge or the biomass as a mixture thereof in a fixed bed updraft gasification reactor, and ii. obtaining biochar ash from biomass after gasification.

2. A method according to claim 1 , wherein the gasification agent in the fixed bed updraft gasification reactor comprises dry air and pure oxygen.

3. A method according to claim 1 , wherein the gasification agents in a fixed bed updraft gasification reactor comprises 0.05 L / min dry air and 0.05 L / min pure oxygen.

4. A method according to claim 1 , wherein the gasification agents in a fixed bed updraft gasification reactor comprises 0.1 L / min dry air and 0.05 L / min pure oxygen.

5. A method according to claim 1 , wherein the gasification agents in a fixed bed updraft gasification reactor comprises 0.2 L / min dry air and 0.05 L / min pure oxygen.

6. A method according to claim 1 , wherein the gasification agents in a fixed bed updraft gasification reactor comprises 0.4 L / min dry air and 0.05 L / min pure oxygen.

7. A method according to claim 1 , wherein the gasification temperature of the fixed bed updraft gasification reactor used for the production of the adsorbent material is 700°C.

8. A method according to claim 1 , wherein the gasification temperature of the fixed bed updraft gasification reactor used for the production of the adsorbent material is 800°C.

9. A method according to claim 1 , wherein the gasification temperature of the fixed bed updraft gasification reactor used for the production of the adsorbent material is 900°C.

10. Biochar ash obtained by a method according to any one of claims 1 -9.

11. Method for producing activated carbon from a biochar ash according to claim 10 for use as an adsorbent material, comprising the process steps of: i. weighing biochar ash samples, ii. mixing with phosphoric acid (H3PO4) and waiting, iii. carbonizing the resulting mixture by burning in the furnace, iv. washing with pure water to remove product impurities, and then drying in a drying oven.

12. A method according to claim 11 , comprising the process steps of: i. weighing biochar ash samples as 75 grams, ii. mixing with 41.67 mL phosphoric acid (H3PO4) at a rate of 1 g / g and waiting for 30 minutes, iii. carbonizing the resulting mixture by burning in the furnace at 600 °C for 1 hour with a heating rate of 5 °C / min, iv. washing with pure water to remove product impurities, and then drying in a drying oven at 100 °C.

13. Activated carbon obtained by a method according to any one of claims 11 or 12 for use as an adsorbent material in wastewater.