Carbon monoxide incineration

Direct-Flame Incinerators. In direct-flame incineration, the waste gases are heated in a fuel-fired refractory-lined chamber to the autoignition temperature where oxidation occurs with or without a visible flame. A fuel flame aids mixing and ignition. Excess oxygen is required, because incomplete oxidation produces aldehydes, organic acids, carbon monoxide, carbon soot, and other undesirable materials. 

The common treatment methods are acidification, neutralization, and incineration. When oxahc acid is heated slightly in sulfuric acid, it is converted to carbon monoxide, carbon dioxide, and water. Reaction with acid potassium permanganate converts it to carbon dioxide. Neutralization with alkahes, such as caustic soda, yields soluble oxalates. Neutralization with lime gives practically insoluble calcium oxalate, which can be safely disposed of, for instance, by incineration. 

Generation and Emission Rates for Polynuclear Organic Material (POM) and Carbon Monoxide (CO) from Incinerators... 

Carbon monoxide, propylene, propane, hydrogen cyanide, acrylonitrile, acetonitrile NOj from by-product incinerator... 

Carbon monoxide Catalyst regenerators, compressor engines, coking operations, incinerators... 

Public concerns about air quality led to the passage of the Clean Air Act in 1970 to amendments to that act in 1977 and 1990. The 1990 amendments contained seven separate titles covering different regula-toiy programs and include requirements to install more advanced pollution control equipment and make other changes in industrial operations to reduce emissions of air pollutants. The 1990 amendments address sulfur dioxide emissions and acid rain deposition, nitrous oxide emissions, ground-level ozone, carbon monoxide emissions, particulate emissions, tail pipe emissions, evaporative emissions, reformulated gasoline, clean-fueled vehicles and fleets, hazardous air pollutants, solid waste incineration, and accidental chemical releases. 

Incineration produces gases and solids, in the form of ash and slag. Combustion gases are composed primarily of carbon dioxide and water, as well as small quantities of carbon monoxide, nitrogen oxides, and small concentrations of organic and inorganic compounds. 

The stable gases produced by incineration are primarily carbon dioxide and water. Depending on waste composition, however, small quantities of carbon monoxide, nitrogen oxides, HC1, and other gases may form. Also, if combustion is not complete, compounds known as products of incomplete combustion (PICs) may be emitted. RCRA regulations control the amount of HC1 released from the APCD. 

PCDD/F and other chlorinated hydrocarbons observed as micropollutants in incineration plants are products of incomplete combustion like other products such as carbon monoxide, polycyclic aromatic hydrocarbons (PAH), and soot. The thermodynamically stable oxidation products of any organic material formed by more than 99% are carbon dioxide, water, and HCl. Traces of PCDD/F are formed in the combustion of any organic material in the presence of small amounts of inorganic and organic chlorine present in the fuel municipal waste contains about 0.8% of chlorine. PCDD/F formation has been called the inherent property of fire. Many investigations have shown that PCDD/Fs are not formed in the hot zones of flames of incinerators at about 1000°C, but in the postcombustion zone in a temperature range between 300 and 400°C. Fly ash particles play an important role in that they act as catalysts for the heterogeneous formation of PCDD/Fs on the surface of this matrix. Two different theories have been deduced from laboratory experiments for the formation pathways of PCCD/F ... 

Releases carbon monoxide, carbon dioxide, and ammonia when heated to 900 °C (Kennedy, 1972, 1972a). Incineration may also release hydrofluoric acid in the off-gases (Sittig, 1985). 

Off-gas from the coke burner ( -Gas) contains nitrogen, sulphur dioxide (SO2), hydrogen sulphide (H2S), carbon monoxide (CO), carbon dioxide (CO2), water vapour and other trace contaminants. The -Gas is directed to the CO Boiler for incineration where sulphur compounds are converted to SO2. The Boiler flue gas is passed through electrostatic precipitators for particulate control and then emission to atmosphere. The CO Boiler also serves as the Sulphur Plant tail gas incinerator. Maximum sulphur emissions are 146 tonnes/day or 10.6% of sulphur contained in bitumen feed to the cokers. 

Products of Incomplete Combustion Emission Limits. Products of incomplete combustion typically are not diiecdy measured during the trial bum. Instead, levels of carbon monoxide (qv) emissions are used as an indication of combustion efficiency. High combustion efficiencies are assumed to result in acceptable levels of products of incomplete combustion. If carbon monoxide emissions are measured at less than 100 ppmv dry basis, the standard is met. However, if emissions are greater than 100 ppmv, no more than 20 ppmv of total hydrocarbons (qv) are allowed at the incinerator stack during the trial bum. 

Acetaminophen is stable under ordinary conditions of use and storage. In the presence of heat and water, acetaminophen will hydrolyze into acetic acid and p-aminophenol. Incineration may produce carbon monoxide, carbon dioxide, nitrogen oxides. 

Incineration is a rapid, exothermic reaction between a fuel (waste) and oxygen (O2). Incineration produces the same end products and by-products, whether the material burned is municipal solid waste, hazardous waste, or medical waste. This is because of the fact that complex fuel molecules first undergo thermal decompositions upon being preheated by the preceding flame, forming smaller molecules such as methane, acetylene, ethylene, carbon monoxide, hydrogen, and alike, and it is the combustion of these smaller molecules that primarily influence the nature of combustion products and pollutants formed. This aspect of combustion chemistry has significantly helped in the development of detailed kinetic mechanisms of combustion for all types of hydrocarbon fuels. Solid decomposition... 

Destruction is accomplished by pyrolysis rather than oxidation therefore, typical products and by-products produced by incineration such as carbon monoxide, carbon dioxide, and oxides of nitrogen are not formed in significant concentrations. The principal products from soil-affixed TCDD using the Huber process are hydrogen, chlorine, hydrochloric acid, elemental carbon, and granular free-flowing soil material. 

Miller and co-workers show an on-stream sampler and a portable GC system to analyze stack gases as part of the requirements of determination of particulate matter from incinerator stacks. The concentrations of carbon dioxide, oxygen, and carbon monoxide are measured and that of nitrogen is calculated by difference. This method is of higher precision and can save time and labor when compared with the Orsat analyzer method. Further, this GC system is portable and all the components are mounted on a 2 ft by 3 ft laboratory cart, which makes mobile measurements possible. A summary of some of the techniques used is presented in Table 6.2. 

Inorganic gases Carbon monoxide, hydrochloric and sulphuric acid, nitrogen oxides (ozone), metal vapours, carbon dioxide, ammonia Firing systems, incinerators, engines, industry... 

---