Air stripping Wikipedia

Air stripping is the transferring of volatile components of a liquid into an air stream It is an environmental engineering technology used for the purification of groundwaters and wastewaters containing volatile compounds Volatile compounds have relatively high vapor pressure and low aqueous solubility characterized by the compound s Henry s law coefficient which is the ratio of the


from the water in a process called stripping The stripping process Figure 1 uses a gas stream to force both the hydrogen sulfide H 2S and ammonia NH 3 out of solution and into the gas phase for further treatment Although air stripping can be used steam stripping which liberates more H


Like cyanide thiosulphate leaching is an alkaline process usually operated in the pH 8 to 10 range so there are no concerns with corrosion and materials used in construction and the process can be applied to heaps and dumps or to stirred tanks The thiosulphate process offers advantages over cyanide leaching in the following situations

Carbon Stripping – Denver Mineral Engineers

A typical glycol stripping solution contains 20 to 25 wt ethylene or propylene glycol and 2 wt sodium hydroxide Sodium cyanide is sometimes added to the solution but it is frequently unnecessary The solution is heated to about 190 deg F and pumped through the carbon stripping vessel at a flow rate of about 2 Bed Volumes per hour Gold and

Elution and Carbon Reactivation Resource book

temperatures low cyanide concentrations low pH and high gold concentration in solution although some of these conditions aren t practically achievable By simply reversing these conditions elution desorption of gold from the carbon occurs The main factor that makes desorption or stripping a simple process is the fact that gold will

Stripping of Plated Finishes Products Finishing

Sep 29 2011 · Cyanide based stripping solutions use sodium hydroxide caustic soda as a source of alkalinity and protection for the steel substrates Cyanide is the complexing agent that helps to remove plated deposits into solution Nitro aromatic compounds are the source of the oxidizing power

An Investigation of Techniques for Removal of Cyanide from

Three difficulties were encountered 1 the stripping of cyanide from the column for Run 1 was slow requiring 48 hours to remove about 50 percent of the adsorbed cyanide 2 the stripping of cyanide was incom plete and 3 cyanide was not effectively and rapidly removed from the sulfuric acid regenerating solution by air sparging

Activated Carbon in Gold Cyanidation

The gold cyanidation process is a primary method of gold beneficiation Activated carbon is a critical component in the beneficiation of gold ore allowing this widespread process to occur because of its ability to recover gold from the gold cyanide complex Depending on the deposit some silver ores may also be processed via cyanidation

Process of stripping gold and silver from carbon Drew

Dec 17 1991 · We claim 1 A process for stripping a metal value selected from gold and silver from activated carbon on which said metal value is adsorbed as a metal cyanide complex which comprises subjecting said metal cyanide complex adsorbed carbon to an aqueous solution of a compound selected from a benzoic acid and substituted benzoic acids and b polyacrylic acids of less than about

US5073354A Process of stripping gold and silver from

Gold and silver are stripped from activated carbon on which they are adsorbed as cyanide complexes by subjecting the activated carbon to a stripping solution comprising as the strippant an effective amount of a compound containing the carboxylate functionality The compound is preferably selected from benzoic and substituted benzoic acids and polyacrylic acids of less than about 100 000 m w

Investigation of Mercury Reduction in Gold Stripping

Furthermore mercury stripping using conventional pressurized cyanide alkaline Zadra was best performed at 80oC minimal amount of mercury reduced and volatilized whereas using the same process only 40 of gold was stripped which makes this process not viable When alcohol was added to the stripping solution at

Seperation of Gold using Cyanide Processing YouTube

Apr 07 2013 · Explanation of Gold Separation Using Cyanide Processing at Milling Plant in the Philippines Ancient gold smelting rare today extract recovery process of refining gold to remove any

Copper Finishes for Various Metals – Electroplating – EPi

Alkaline non cyanide process E Brite 30 30 is an easy to use one tank process that eliminates the need for cyanide or pyrophosphates Optimal adhesion allows for plating directly onto a variety of metals Uniform low current density distribution with greater throwing power than cyanide copper

Instructions for the Gold Stripping Process

Step By Step Process Heat the stripping solution to just below boiling Some of the gold that is stripped into the cyanide water will plate out onto the sides of the pot or onto the graphite rod Some will remain in solution Contact Shor for instructions for recovery of the gold

PDF ZADRA Elution Circuit Optimisation and Operational

ZADRA Elution Circuit Optimisation and Operational Experience at the CIL Plant of Gold Fields Ghana Limited 4 th UMaT Biennial International Mining and Mineral Conference

Precious Metal Recovery Cyanide Destruct Systems

Our specialized precious metal recovery process for Cyanide solutions and gold plated scrap enables us to process electronic circuit boards on site and attain a level of 100 recycled With Cyanide stripping you get a faster return and a more accurate assay

Zadra elution circuit Pyrometallurgy Roasting Smelting

The inlet screens to the strip vessel are one location for scale formation due to the pressure drop The heat exchangers are another location due to temperature and pressure drop Have these two locations been checked Flow restriction due to scale will reduce the amount of heat that can be transferred to the elution process

Choosing and Troubleshooting Copper Electroplating Processes

Feb 22 2011 · Alkaline Non Cyanide Solutions Concern for worker safety and government regulations on cyanide have made the use of non cyanide coppers desirable However it is questionable if they can replace cyanide processes in all applications especially for rack plating zinc die castings due to the formation of a non adhering immersion copper deposit

Leo Chang YouTube

Usually we used to use chemical methods aqua regia or cyanide to strip Au plating layer However aqua regia has strong corrosion and easy to damage underneath Moreover it is hard to purchase o


The treatment process at the IWTP requires the use of toxic chemicals such as sulfuric acid caustic chlorine and other hazardous materials There are a number of commercially available non cyanide metal stripping processes that can be implemented to replace cyanide based metal stripping

Gold recovery from loaded activated carbon ScienceDirect

Ion exchange technology may be used in the stripping gold cyanide from aqueous organic solutions 4 Conclusions This study demonstrates that gold cyanide which is adsorbed on the activated carbon is quickly recovered from the activated carbon by a two step process at ambient temperature This method is relatively safe and simple


stripping copper plating a discussion started in 2000 but continuing through 2017 2000 q we manufacture very precise aircraft engine jet seals from 17 4ph stainless steel they are copper plated 0 4 mils min selected areas to prevent nitriding after nitriding the copper is stripped in a non electric immersion sodium cyanide solution


In the gold stripping operation time there is only one fifth of the traditional cyanide alchemical method Non toxic and environmentally friendly At present most miners in China Asia and Africa still use cyanide stripping technology but the cyanide stripping process will cause great damage to the human body

Cyanide Leaching Of Gold Mine Engineer Com

Gold Cyanide Solution Leaching Gold With Cyanide Since the 1890 s cyanide has been used to recover gold from gold bearing ores And today over 115 years later most of the worlds gold is recovered with cyanide playing a large part in the beneficiation of the yellow precious metal


Alkaline cyanide free process for electroless stripping of nickel from steel copper brass and German silver 01041 Stripper L 60 30 KB Two stage chemical process for the removal of tin tin lead and lead deposits from copper by spray methods Application in continuous plating lines

Sampling and Analytical Methods Cyanide Occupational

Filter samples are transferred to a 50 mL plastic beaker and desorbed with 25 mL 0 1 N NaOH for at least 30 minutes with occasional agitation If an analysis other than cyanide is to be done then an aliquot of the sample is measured out for cyanide analysis into a

7 Air Stripping ScienceDirect

7 AIR STRIPPING 7 1 Physico chemical Principles of Air Stripping The stripping process is used to remove volatile gases such as hydrogen sulfide hydrogen cyanide and ammonia by blowing air through the waste water The process is therefore to be considered as

Fundamentals ofFundamentals of Sour Water

Fundamentals ofFundamentals of Sour Water StrippingSour Water Stripping Presented at the Brimstone Sulfur Symposia V il C l d S t b 2008Vail Colorado September 2008 Gasification and Other Thermal Process Cyanide Caustic Chloride