Steward has a state of the art testing facility capable of measuring to less than 1 ppt mercury concentration, and most other elements within ppt levels. Steward has the facility for material characterizations such as BET, pore size, particle size, surface morphology, etc. Steward also has multiple lab scale and pilot scale Thiol-SAMMS® treatment systems to study and demonstrate, in both lab and field conditions, the Thiol-SAMMS treatment approach for customer waste streams.

Facilities

• 5,000 sqare foot test facility
• ICP-MS: Agilent 7500 cx. The state-of-the art Agilent 7500 cx is equipped with fully automatic computer controlled torch position, Shield Torch System, high efficiency digital drive 27 MHz ICP RF generator, highest frequency digitally synthesized 3 MHz RF Quadrupole Driver, MicroMist glass concentric nebulizer, additional carrier gas option, Omega lens, Octopole reaction system and many other features. It can analyze wide range elements: Hg, Ag, Au, Pd, Cu, Cd, Fe, Ni, Zn, As, Cr, Se, Ge, Br, I, V, Mo, Tc, Th, U, Pu, Am, Cs and many others. The detection limit for most of elements is in part per trillion range.
• Hg testing: Tekran 2600 Cold Vapor Atomic Fluorescence Spectrometry. This Hg analyzer is capable of determining mercury concentration in liquid phase to the detection limit of EPA 1631 (0.5 part per trillion). This system is equipped with an auto sampler and able to analyze many samples a day. It is also able to determine mercury concentration in gas phase.
• Micromeretics Tristar Surface Area and Porosity Analyzer
• Microtrac S3500 particle size analyzer
• Optical microscopes
• Scanning electron microscope equipped with EDAX
• Thermal gravimetric analyzer
• Other general lab equipments: sub-miligram scales, bench top shaker, hot plates, oven, DI-water system (1 and 18 MΩ) and many others.
• Lab scale continuous stirred tank reactors coupled with a membrane system: this system is able to study and determine the suitable treatment approach for customer waste streams using Thiol-SAMMS.
• Pilot scale continuous stirred tank reactors coupled with a membrane system: this system is able to evaluate the treatment approach using Thiol-SAMMS at the pilot scale (from 1 gpm to 10 gpm).

Steward can conduct treatability studies to help develop a suitable treatment approach in order to reduce the mercury, lead, cadmium and other soft heavy metal concentrations from the client’s effluent stream.

Treatability study description

Step 1 – Characterization of the Waste Stream

Although only a few chemicals have a strong interfering effect on SAMMS performance, gaining as much information on the waste stream as possible is essential to design and develop the most cost effective treatment strategy. Steward will begin by first gaining a thorough understanding of the waste stream and then perform an initial bench test on SAMMS adsorption performance using the client samples to determine the best chemical and equipment design approach for optimum metal reduction using SAMMS.  Steward has the capability, but is not limited to, measuring inorganic, non-metallic constituents, metallic constituents, and organics. In addition, total dissolved solids, total suspended solids and solid particle size may be determined prior to designing solutions.

Step 2 – Selection of Treatability Laboratory Methods

After determining the chemical makeup of the influent, Steward will explore methods to achieve the best performance of SAMMS. If there are interfering species in the influent, these methods may involve using pretreatments such as chemical precipitation, oxidation, pH adjustment, micro-filtration or combinations of these treatment methods.

Step 3 – Perform Bench Testing

Steward will perform a series of laboratory scale bench tests to define and address elements that may impact SAMMS performance, reaction kinetics and mass transfer and maximum adsorption of mercury.

Examples of laboratory bench methods utilized by Steward in a study are as follows:
a. Filtration – if required we will evaluate physical pretreatment and filtration methods.
b. Pretreatment – Steward is not concerned about the effect of most cations and anions with SAMMS but will evaluate and develop the best pretreatment method to address any interfering compounds present in the waste stream. One such method is ozone injection. Other interferences, if any, may be addressed after chemical analysis of the sample for in depth evaluation.
c. Static bench testing – To establish a baseline, Steward performs a series of static bench tests. This may include, but not be limited to - pH effect, SAMMS concentration effect, SAMMS Step Addition effect, and interference effect.  Data validation is done with matrix spike analysis.
d. SAMMS Lab Scale Multi-Cell Membrane System – To gain insight into SAMMS performance we may evaluate the selected influent sample using our unique SAMMS lab scale multi-cell membrane system with four contactor tanks.

Step 4 - Analyze and Report Results

Steward will analyze the results and provide a full report with next step recommendations.

If you have a need for testing, please contact us.