Compact, mobile and autonomous unit for odor control through biofilter

Abstract

This compact, mobile, and autonomous unit for odor control using a biofilter consists of a biofilter constructed from modifications made to a marine container. The biofilter will consist of a false bottom made of fiberglass mesh, where the odorous gas will be distributed homogeneously in the support medium; a support medium composed of gravel, peat, and wood chips, where the biological removal of odorous compounds will occur; and an automatic humidity control system for the support medium using a micro-spraying system, programmable logic controller, and timer.

Description

1 / 4 Compact, mobile, and autonomous unit for odor control using a biofilter. This refers to the Utility Model Patent application. In recent years, there has been an increase in the number of complaints regarding odors released from sewage systems. According to POMEROY, 1982, apud MATOS, 2002, BELLI FILHO et al 2001, there are many alternatives for the treatment of foul-smelling gases, which, depending on the characteristics of the pollutants, can be removed through physical and chemical methods such as thermal oxidation / chemical scrubbers, ozonation and adsorption, using activated carbon, and biological methods such as biofiltration. Although physicochemical techniques can efficiently remove odorous compounds from the gas stream, under certain conditions, the need for daily addition of chemicals and the replacement of the adsorbent results in a relatively high operating cost when compared to biological treatment techniques. Therefore, biofilters could be an attractive alternative for odor control if mechanisms are incorporated that allow for better process control, a critical aspect of biofilters. Odor treatment using biofilters, in simplified terms, consists of passing the odorous gas through a support medium containing active biomass where the biological treatment of the 25 odorous compounds will take place. 2 / 4 The performance of the biofilter depends, among other factors, on the material that constitutes the support medium, the adequate distribution of the odorant gas in the biofilter, and the humidity control of the support medium. Therefore, seeking to optimize these aspects, the biofilter, the subject of patent application 5, will have the following characteristics: • The biofilter support medium will consist of gravel, peat, and wood chips. With this composition and in appropriate proportions, the support medium will exhibit: a high specific surface area and a high moisture retention capacity provided by the peat; Maintaining porosity over time due to wood chips is an important aspect in terms of saving electrical energy (lower power of the exhaust system) and resisting the acidity of the product generated in the biological oxidation of hydrogen sulfide gas. The high specific surface area of ​​the support medium is a fundamental aspect in the transfer of odorant compounds from the gas phase to the biofilm. Insufficient transfer is probably the reason for the poor performance of some biological systems (WEF, 1995). 2. To prevent preferential flow of the odorous gas into the support medium, a false bottom will be created in the container. The false bottom will consist of fiberglass grids supported on the sides and in the center of the container. To provide good distribution of the odorous gas without increasing pressure loss, the opening of the grids will be greater than 50%. • According to Von Bernuth et al (1999 apud ZHANG et al, 2002), maintaining microbial activity requires levels of 3 / 4 humidity of 40 to 70%. Very high humidity can cause compaction of the filter medium, resulting in reduced porosity and compromising gas flow. To ensure the humidity of the support medium remains within this range, the biofilter will be closed, thus eliminating the effects of sun and rain; and equipped with an automated micro-spraying system to control the humidity of the support medium. Humidity control will be achieved through a micro-spraying system, a programmable logic controller, and a timer. The timer adjustment will be made during pre-operation, at which time the amount of water to be added to the support medium at each time period will be defined. The biofilter will be constructed using adaptations made to a 20-foot Dry Box shipping container and will have the capacity to treat up to 1,300 Nm3 / h of odorous gas. Drawings 1 / 3, 2 / 3 and 3 / 3 show the plan and cross-sections of the biofilter. The biofilter will consist of: a shipping container (01); a nozzle through which odorant gas will be blown (02); a false bottom through which the odorant gas will be distributed in the support medium (03); a support medium composed of gravel, peat and wood chips (04); an automated micro-spraying system for adjusting the humidity of the support medium (05) and nozzles for the treated gas outlet (06). It is estimated that the support medium has a useful life of more than 2 (two) years. Its replacement can be carried out on-site or by centralizing this operation in another unit. This is possible due to the ease of transporting the biofilter (container). 4 / 4 Using a container to construct a biofilter offers advantages such as low cost compared to fiberglass or polypropylene, materials typically used in biofilter manufacturing, and ease of transport. To mitigate the aggressive effects to which the biofilter will be exposed during operation, the container will be internally coated with sulfuric acid-resistant paint. The ease of transporting the biofilter will allow for the centralization and mechanization of the activity of changing the support medium, which is the most laborious activity in the operation of this system. The possibility of transporting the biofilter, combined with its modulation, will allow the replacement of the device with a saturated support medium by a new one, with minimal interruption of the odor control system operation (just have a spare unit). To accelerate the start of biological activities in the support medium, during the replacement of the support medium, a fraction of it will be mixed with the material that will be placed in the biofilter.

Claims

1 / 1 Claim 1. Compact, mobile, and autonomous unit for odor control using a biofilter, odor control device, of the type comprising: a. at least one odor gas inlet nozzle (2); b. false bottom (3) consisting of grates; c. support medium (4) for filtering odorous gases; d. automatic control of the moisture content of the support medium (4) through an automated micro-spraying system (5), programmable logic controller and timer; and and at least one treated gas outlet nozzle (6); characterized by the biofilter being constructed on a base of a shipping container (1), by means of adaptations made inside said shipping container (1), the biofilter being closed, in which, - the false bottom (3) is positioned at the bottom of the shipping container (1) and consists of grids supported on the sides and in the center of said shipping container (1), through which the odorant gas is distributed into the support medium (4); - the inlet nozzle (2) is positioned in the false bottom (3); - the inlet nozzle (2) is located at the bottom of the shipping container (1), through which the odorant gas is blown; - the support means (4) is positioned on the false bottom grids (3); and - the micro-spraying system (5) and outlet nozzle (6) are fixed to the top of the shipping container (1). Petition 870260076879, dated 07 / 31 / 2026, page 13 / 15

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