How to control foul gases during the production process

Establishing a negative-pressure washing system does not require significant investment. By creating a negative pressure, unpleasant odors are drawn into the washing system, where they are destroyed using water or other alkaline substances; this can be beneficial for the surrounding environment. As for the method of creating this negative pressure, it needs to be determined based on the specific conditions in your situation

The negative pressure washing method is good, but the sealing issue of the entire system is very difficult to resolve. Also, if there are many emission points, the investment will be substantial.

– It is necessary to address the pollutants that cause odors and their sources separately. －－The odors from the slaughter industry can be absorbed using activated carbon (activated carbon fibers are preferred, as they have an odor-absorbing capacity more than 10 times that of ordinary activated carbon), and then released through exhaust stacks of a certain height. – Methods for dealing with the unpleasant odors generated during sludge concentration and dewatering processes in the biochemical treatment of industrial wastewater, urban sewage, and other types of waste water: Dilution before discharge is generally used; in areas where the surrounding environment is sensitive and appropriate conditions exist, methods such as incineration or activated carbon adsorption can be employed ； —in chemical manufacturing, gases with strong odors such as methanethiol and amines are often produced; chemical absorption is required to completely eliminate these odor-causing pollutants through chemical reactions, for example by using alkaline solutions for absorption ； Pesticide manufacturers such as Shandong Dacheng Group (which produces dozens of products including chlorine, dichlorvos, paraquat, etc.) use pipelines to convey the foul-smelling substances generated in various production areas of the company to incinerators, where they are burned using hydrogen as fuel. This approach is feasible only if there is a chlor-alkali workshop available to provide hydrogen (most pesticide factories have such workshops). Additionally, the design of the incinerators must take into account measures to control dioxin pollution, as well as the installation of dust removal systems. Although measures such as combustion in draft boilers, oxidation, and absorption are currently being employed, the effects are not very significant due to sealing issues. – In my opinion, introducing odors into the boiler hardly serves any purpose: the boiler’s structure is not suitable for burning, and it can also reduce the boiler’s combustion efficiency, among other things. — I’ve blurted out all this nonsense; I hope the moderator will forgive the mistakes! (PS: Mods’ posts can be discussed enthusiastically in the crafting section.) :) )

Waste gases are generally classified as acidic or alkaline; acidic gases are easier to treat. For alkaline gases, multiple absorption stages are usually required. There are absorption units in the main processing area, and the gases are then processed collectively before being sent to incinerators for burning. Incinerators require significant investment – I once visited Syngenta’s incineration facilities; the entire system with an air intake capacity of 80,000 cubic meters cost over 20 million. Our factory has thermoelectric boilers, which can be utilized for this purpose; however, the gas fed into the boilers needs to be alkaline and dry, so further pre-treatment is required. But the sealing of the system is currently the most difficult issue to resolve. The problems in our factory have not been completely resolved yet. This post was last edited by The Western Assassin Ouyang Feng on 2008-12-22 20:53.]

The moderator is absolutely right! But I strongly disagree with using thermoelectric boilers and similar devices to burn malodorous pollutants. Doing so may result in a high oxygen content in the boiler and a large excess air coefficient, affecting the flue gas emission concentration and making it easy for it to exceed the specified limits ； Air leakage also affects the efficiency of the boiler. The investment in incinerators is quite substantial; Heilong Chemical Pesticides Company spent around 10 million as well. You might want to take a look at Shandong Dacheng Group – they do an excellent job! In practical work, odor treatment sounds simple, but few people manage to do it well in reality!

Biological trickling beds can be used to treat malodorous gases and VOC gases. The biological method has strong adaptability, can treat various pollutants with different physical properties, and has low operating costs. It is recommended that everyone communicate more. neterli@hotmail.com

Collect the locations where there is leakage, and address each problem one by one

Organic sulfurs such as methanethiol generally have a very strong unpleasant odor; it is advisable to design the system in such a way that leaks are minimized. The exhaust gases should be directed to an absorption tower using exhaust fans, and alkaline solutions are typically used for absorption. Depending on the concentration of the gases, single-stage or multi-stage absorption can be employed; in cases where the odor is particularly severe, additional treatment using activated carbon before discharge may be necessary； For foul-smelling gases that leak into the workshop air, fans are generally used to draw them together for subsequent absorption, in order to minimize the unpleasant odor in the workshop air.