Carbon conditions

The main difference between gas works and coke oven practice is that, in a gas works, maximum gas yield is a primary consideration whereas in the coke works the quality of the coke is the first consideration. These effects are obtained by choice of a coal feedstock that is suitable to the task. For example, use of lower volatile coals in coke ovens, compared to coals used in gas works, produces lower yields of gas when operating at the same temperatures. In addition, the choice of heating (carbonizing) conditions and the type of retort also play a principal role (10,35). 

Carbonate and phosphate control is vital. If a minimum carbonate alkalinity of 250 mg/1 expressed in terms of CaC03 is consistently maintained when carbonate control or sodium ion exchange softening is used, a residual of soluble phosphate need not be maintained. A residual of soluble hardness up to 5 mg/1 expressed in terms of CaC03 is then usually found in the BW, but scale formation may be minimized by phosphate or carbonate conditioning treatment. 

NOTE It has been shown that in the absence of phosphate, carbonate conditioning can produce precipitated solids in a non-adherent and mobile form by adjusting the proportion of calcium, magnesium and silica to correspond with the relationship ... 

At heat fluxes greater than or equal to 300 kW/m2 it is recommended that caustic alkalinity be maintained at 10 to 15% of the TDS concentration, if phosphate conditioning is practiced. If carbonate conditioning is practiced, see note 11. 

Where carbonate conditioning programs are employed, it should be noted that, apart from high sludge volumes, C02 also results from the added sodium carbonate and the alkaline earth FW contaminants, as shown here ... 

It is difficult to manage the problem of high sludge production in lower pressure boilers where precipitation programs, especially carbonate conditioning, are used because it has a knock-on effect resulting in condensate line corrosion. The answer is always to install a water softener. The payback time is very short because of the reduced BD necessary as a result of decreased sludge production. 

In most of these reactions, it is nitrogen of a urea, thiourea, isothiourea, or an amidine which is the nucleophile for the addition to an appropriately situated electrophilic carbon. Conditions which enhance the electrophilic character of the carbon, or the nucleophilicity of the nitrogen, promote cyclization. Most commonly, this cyclization is affected by nitrogen addition to the electrophilic / -carbon of a Michael acceptor, and can be performed under acid or basic conditions. 

Dr. Friedel. No. Products of the pyrolysis of coal under high temperature carbonization conditions surely must arise from degradation. The quantitative prediction of C7 alkane isomers from coal may possibly indicate a relationship in compositions of coal and petroleum. The hydrocarbons from each perhaps should be similar since both are supposedly derived from organic plants ... 

It is my contention that the optical and physical properties and the optical structure produced during the destructive distillation or thermal decomposition of vitrinite is closely related to mode of carbonization and, in the case of pitch, is intimately related to the method of pitch preparation. For instance, a pitch may be produced from a high or low temperature tar, from a primary cooler tar, or from a flushing liquor tar. In addition, it may be air blown, thermally or chemically treated, straight distilled, or cut back, just to mention a few. Under similar carbonization conditions almost any one of these pitches will produce a coke which has certain characteristics that are related to the parent pitch. Even pitches similarly processed from the tar can differ in the content of quinoline- and benzene-insoluble material and P-resin, and can contain more than one distinct liquid phase. None of these points of difference has been discussed by Dr. Taylor or even recognized in the preparation. To interpret the structure of pitch coke divorced from a knowledge of the pitch source and/or carbonization conditions can lead to erroneous conclusions. These are pertinent data omitted by the authors. 

The preparation of a carboxylic ester by a variant of the Grignard carboxylation route has been described.61 The arylmagnesium bromide is first prepared and added to an excess of diethyl carbonate, conditions which... 

Modification of porous inorganic materials by carbon makes it possible to obtain porous carboniferous composites with high thermal and chemical stability and strength. To introduce carbon into pores, both gas phase pyrolysis and carbonization through thermochemical solid-phase reactions are employed. The formation of carbon structures depends on carbonization conditions process rate, precursor concentration, presence of catalyst, etc. [1-3]. Phenolic resins, polyimides, carbohydrates, condensed aromatic compounds are most widely used as polymeric and organic precursors[4-6]. 

In Section 4 we report on a broad precursor screening with regard to polymer composition, additives, influence of spinning parameters, stabilization and carbonization conditions. 

By careful control of carbonization conditions this is done by controlling heating rate, heating temperature, and choice of inert gas or vacuum during the process [76]. 

Kumar M, Gupta R.C. (1997). Influence of Carbonization Conditions on the Pyrolytic Carbon Deposition in Acacia and Eucalyptus Wood Chars. Energy sources. 19,295-300. 

Austenitic stainless steels like 31 OS, 316, or 316L are typically used for the construction of cathode and anode current collectors and bipolar separator plates. Corrosion of these steel components is a major lifetime-limiting factor in MCFC. The corrosion behavior of stainless steel components in molten carbonate conditions has been studied extensively during the past decade. Research is being aimed at increasing the corrosion resistance of these components by altering the alloy composition or by surface modification techniques. ... 

The SPARG process is essentially the same as a conventional steam methane reformer except for the addition of sulfur to the catalyst [9]. An important feature, however, is a prereformer to convert heavy hydrocarbons in the natural gas to methane to prevent them from cracking under the extremely low steam to carbon conditions of the reformer [10]. 

Fluorine cells use carbon anodes, steel cathodes, and nickel or monel wine mesh diaphragms contained in a monel tank with a water jacket for cooling. Cells operate at about 6 kA, 10—12 V, and 95—105°C. Energy consumption for fluorine production is about 22 kWh/1. Figure 6 is a diagram of a fluorine cell. Fluorine cell voltages ate iacteased by the formation of fluorinated carbon. Conditions for the formation of (CF) and on anode... 

Carbon precursor Template zeolite Carbonization conditions Pore structure parameters ... 

Most of the literature in the past, including that by the author (13). reflected composition of tars produced as a byproduct of charcoal manufacture. These tars, from different biomass materials, exhibit like chemical compositions. The chars produced under similar carbonization conditions also exhibit similar physical and chemical properties (24). During the last decade or so, pyrolysis process research has confirmed that both the yield and chemical composition of pyrolysis oils are very dependent on reaction conditions (see e.g., 14-16.25.26). All biomass oils are not the same oil formation conditions determine oil composition. Similarly, it has been reported that different biomass feedstocks pyrolyzed under similar process conditions can give oil products with similarities in chemical composition (e.g., 27-30). 

The amount of heat required to decompose wood (AHr) will depend on the operating conditions used and the degree of conversion that has been reached. Under usual carbonization conditions, overall the reaction is known to be exothermic. Under vacuum pressure... 

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