Effluent plant design

The principal source of solid waste in coal gasification is ash or slag from the feed coal. The amount of this solid waste is a direct function of the ash content in the feed coal. This ash is normally the only solid waste coal gasification generates. Plant operators commonly add (or leave in) about 20-30 wt% water to solid waste for dust control and optimum bulk density. This water may contain dissolved salts and minerals if it is part of the plant water effluents. Some zero water effluent plant designs may also add a small amount of solid salts and minerals (from water effluent evaporation) to the coal ash. 

A larger number of researchers have measured FMs in final effluent from wastewater treatment (Table 5) because this is the most important wastewater parameter for accessing FM discharge to aquatic ecosystems. The concentration of FMs in final effluent is a function of the FM concentration in influent and the efficiency of FM removal across the plant (including plant design and operation). 

Preliminary design of a central effluent plant (Section V.B) pH control of a strong-acid/strong-base system (Section V.C)... 

The objective of this case-study was to evaluate a proposed design for a treatment system for a central effluent plant dealing with waste streams from many sources. 

Not all power plant designs fit into an upstream or downstream category. Integrated systems let carbon move through the entire process, but they prevent normal dilution of the output flue gas, so that the effluent is concentrated CO2. While most of the plants in this category are still in an early development phase, they promise to combine high efficiency, virtually zero atmospheric pollution, and complete capture of all CO2. All avoid the intake of air. 

In the latest version of aluminum chloride plant designs, the alkylation reactions occur in a homogenous liquid phase at 160-180" C. The conditions of the alkylation reactor prohibit the recycle of PEB to the reactor. As a result, these plants have a separate transalkylation reaction zone. The recycle PEB stream is mixed with the alkylation reactor effluent and fed to the transalkylation reaction zone. The aluminum chloride present in the alkylation reactor effluent catalyzes the transalkylation reactions. 

Better environmental performance. Modem process design should aim to zero-effluent plants by minimisation of gaseous emissions and of process waste, including wastewater. 

This should also be everybody s concern ETP. Precautions shall be taken for plant design, operation and maintenance to minimise generation of wastes, recycle of effluents (if possible), and treatment of effluents. Disposal of wastes generated during plant operations can be done through suitable paths for disposal of incineration, secured land fiU, etc. 

Design and qualification of a heat treatment effluent plant... 

Assuming that heat is the chosen method of processing the effluent generated by the bioindustrial process, what design considerations are there for the effluent plant itself ... 

The most recently designed effluent plant at CAMR is shown in Figure 12.5. In this case, the design emphasis is on containment and operational versatility in the type of agents which can be accommodated. 

Removal of Carbon Dioxide and Methanation. About 17 to 19% of the effluent gases is carbon dioxide. This undesirable byproduct is usually removed by a number of methods, such as physical absorption, chemical reaction, or a combination of both. Removal methods include monoethanolamine process for removing acid gases, activated carbonate process based on absorption of carbon dioxide by potassium carbonate, and physical absorption systems in which solvents and agents that remove carbon dioxide are us. Generally, the choice of carbon dioxide removal depends on the overall plant design and the integration procedures needed. 

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