SINOKLE CDOF Technology Solves the Advanced Treatment Challenge of Distillery Wastewater
Alcohol (ethanol) production is an important basic industry of the national economy. Its products are widely used in chemicals, food, daily cosmetics, pharmaceuticals and hygiene, and often serve as the base material of alcoholic beverages, as extractants and dissolution media, and as surfactant components of cleaning products.
At present, domestic ethanol feedstocks come mainly from three categories: about 75% comes from starchy materials such as corn, dried sweet potato and cassava; about 20% uses molasses, a by-product of the sugar industry; and about 5% is obtained through chemical synthesis. Starch-based feedstocks therefore constitute the absolute mainstream of ethanol production.
The stillage generated during production is one of the most prominent pollution sources of the food and fermentation industries. Owing to various constraints, many producers still have considerable room for improvement in comprehensive resource utilization.
This wastewater is notable for its high organic content, high temperature and abundant suspended solids. Research on its treatment started early and the technology iterates rapidly. The fibrous matter contained in the waste liquid, such as crushed cassava peel and rhizomes, constitutes insoluble chemical oxygen demand (COD); polysaccharides such as cellulose and hemicellulose contained in cassava itself are difficult for yeast to utilize effectively during fermentation and therefore remain in the form of soluble COD; in addition, the wastewater also contains impurities such as inorganic ash and silt. Together, these constituents constitute the main challenges in the purification and treatment of this wastewater.
Although biochemical methods can usually treat this kind of wastewater effectively, in order to further optimize the feasibility of subsequent biochemical treatment and focus on solving the problem that the residual COD does not fully meet discharge standards, SINOKLE Technology Co., Ltd. has launched a new advanced treatment process based on its own innovative achievements.
The process shown in the figure is CDOF (Cyclonic Dissolved Ozone Flotation unit), a technology independently developed by SINOKLE. CDOF creatively combines ozone advanced oxidation technology, cyclonic separation technology and dissolved-air flotation technology to achieve efficient comprehensive removal of various difficult-to-treat wastewaters.
The ozone catalytic oxidation process has a short flow, simple equipment, small and compact treatment units and a small footprint, with few electric devices, low power consumption and low operating costs. It is easy to operate and can be automatically controlled, simplifying the requirements for on-site operation. When the water quantity and quality change, regulation of water quality and quantity can be carried out, showing strong adaptability and strong shock-load resistance. It can be combined with other technologies (such as biochemical methods) to give full play to their respective advantages and further improve the treatment effect.
Ultra-fine micro-nano bubble generation technology: a micro-nano bubble generation system with efficient gas dissolution, release and mixing as its core equipment. Micro-nano bubbles are extremely fine bubbles with diameters smaller than 50 microns. They rise slowly in water, stay for a long time and dissolve with high efficiency, and possess properties such as self-increasing dissolved oxygen, negative surface charge and an abundance of strongly oxidizing free radicals.
Bench-scale data for cassava ethanol wastewater from an enterprise
Experimental conclusion: after treatment by this process, at an ozone dosage of 150 mg/L, the effluent COD was 238.8 mg/L, the COD removal was 186.55 mg/L, and the ozone consumption ratio was 0.80. The test not only confirmed that this process can effectively solve the problem of meeting the wastewater COD standard, but also significantly improved the biodegradability of the wastewater, creating more favorable conditions for the subsequent biochemical treatment stage.
