Explore chapters and articles related to this topic
Simultaneous Optimization Aspects in Industrial Gas Sweetening Process for Sustainable Development
Published in Satya Bir Singh, Alexander V. Vakhrushev, A. K. Haghi, Materials Physics and Chemistry, 2020
Debasish Tikadar, Chandan Guria, Ashish M. Gujarathi
Bisulfide ion dissociation: HS−(aq)⇌H+(aq)+S=(aq)
Plastics
Published in Ronald M. Scott, in the WORKPLACE, 2020
Some accelerators are listed below: hexamethylenetetraminethiocarbanilidebenzothiazolyl disulfidetetraethylthiuram bisulfide (disulfiram)diphenylguanidine phthalatetetramethylthiuram disulfide (thiram)thiocarbanilidemercaptobenzothiazole
Ancillary Substances
Published in Robert H. Kadlec, Treatment Marshes for Runoff and Polishing, 2019
Hydrogen sulfide exists in water solution as un-ionized (H2S) or singly or doubly ionized (bisulfide, HS– or sulfide, S–2), depending on water temperature and pH. The two dissociation reactions are:
Syngas cleaning for coal to methanol demo plant – H2S and COS removal
Published in Chemical Engineering Communications, 2021
Aykut Argonul, Omer Orcun Er, Ufuk Kayahan, Alper Unlu, Mustafa Ziypak
The syngas leaving the COS hydrolysis reactors was cooled down almost to ambient temperature by a water-cooled heat exchanger. The cooled syngas was then fed to a packed column gas scrubbers. A caustic (NaOH) solution with a pH of 11–11.5 was sprayed from the top of the column onto the packing using an L/G mass ratio of approximately six. NaOH reacts with H2S to form sodium bisulfide and sodium sulfide (see reaction (2) & (3)). It should be noted that CO2, due to its acidic nature, also reacts with caustic as an unwanted side reaction in such systems (see reaction (4)).
Sulfate and metals removal from acid mine drainage in a horizontal anaerobic immobilized biomass (HAIB) reactor
Published in Journal of Environmental Science and Health, Part A, 2020
Juliana Kawanishi Braga, Omar Mendes de Melo Júnior, Renata Piacentini Rodriguez, Giselle Patricia Sancinetti
Once the total dissolved sulfide (TDS) is divided into unionized sulfide (H2S) and bisulfide (HS−) at neutral pH (Eq. (1)),[84] the concentrations of these sulfur species in the liquid medium was calculated according to Eq. (2).
Fouling Detection in Industrial Heat Exchanger Using Number of Transfer Units Method, Neural Network, and Nonlinear Finite Impulse Response Models
Published in Heat Transfer Engineering, 2022
Željka Ujević Andrijić, Nenad Bolf, Nikola Rimac, Adriana Brzović
The heat exchanger (E-007) of interest is located in the integrated hydrotreatment and hydrocracking plant, which examined segment is shown in Figure 1. Typical piping and instrumentation diagram symbols (process measurements and control loops) for examined segment are also seen in Figure 1. LI and LIC indicate Level Indicator and Level Indicator and Controller, FC and FIC indicate Flow Indicator and Flow Indicator and Controller, PI and PIC indicate Pressure Indicator and Pressure Indicator and Controller, and TI and TIC indicate Temperature Indicator and Temperature Indicator and Controller. Numbering under FIC and TI shown in Figure 1 represents the control loop number or instrument number. The hydrocracking process starts with the preheating of a diesel product coming from the fractionation section. This raw material then enters heat exchangers where it gets additionally heated by reactor effluents. It then enters the furnace, to be heated to the target temperature. The hydrocracker reactor converts raw material inputs into diesel and light products while removing sulfur, hydrogen and metals. The reactor effluent is used for the production of high-pressure steam E-006, shown in Figure 1. The cooled reactor effluent enters the hot high-pressure separator V-005 (HHPS). The input flow is separated into hydrogen-rich steam and liquefied hydrocarbons. Hot steam from the HHPS, cooled and partially condensed by preheating recycled gas from the reactor first in the heat exchanger E-010 and followed by the heat exchanger of interest E-007 is shown in Figure 1. Partially condensed stream then flows into the HHPS vapor air cooler (EA-008). During the cooling of HHPS steam, ammonium bisulfide salt precipitation occurs in heat exchanger pipes. Ammonia and hydrogen sulfide, formed in the reactor from sulfur and nitrogen in the feed, combine to form solid ammonium bisulfide. These solids can deposit along the air cooler tubes, thus reducing heat transfer efficiency. Special nozzles are installed in the exchangers that occasionally wash the deposits with water.