MEETING NEVADA DEP-BMRR PROFILE II PARAMETERS WITH ... · meeting nevada dep-bmrr profile ii parameters with electrocoagulation based treatment solutions b. denney eames, bryan nielsen,

MEETING NEVADA DEP-BMRR PROFILE II

PARAMETERS WITH

ELECTROCOAGULATION BASED

TREATMENT SOLUTIONS

B. DENNEY EAMES, BRYAN NIELSEN, CHARLES LANDIS

IWC-14-20

International Water Conference 2014

Executive Summary

•Electrocoagulation (EC) introduction• History and basics

• Overview of the Science of Electrochemistry

•Review three Mine water treatment case

studies for EC treated water meeting

Nevada Profile II targets

Introduction to Electrocoagulation• First patented in 1906 by A. E.

Dietrich

• Original patent was used to treat

bilge water from ships

• Multiple attempts have been

made to commercialize the

technology with varying degrees

of success

• New regulations have put

pressure on industries to explore

innovative solutions

• Electrocoagulation has re-

emerged as a viable technology

Electrocoagulation Today

International Water Conference 2014

• Electrocoagulation is

used in many industries

today

• Stormwater Treatment

• Environmental Remediation

• Marine Pollution Prevention

• Automotive Cleaning

• Food and Beverage

• Mining

• Oil & Gas

Electrocoagulation PrinciplesElectrocoagulation is a process

utilizing “sacrificed” anodes to

form active coagulants which are

used to remove pollutants by

precipitation and flotation in-situ.

“Compared with traditional chemical

coagulation, electrocoagulation has,

in theory, the advantage of removing

the smallest colloidal particles; the

smallest charged particles have a

greater probability of being

coagulated because of the electric

field that sets them in motion.”

-MF Pouet, 1995

Electrocoagulation Principles

• The electrical current releases

positively charged metal ions that

attract a disproportionate quantity of

negatively charged contaminants

• Small particles agglomerate into larger

particles through precipitation and

adsorption

• Gas generated at the cathode assists in

separating the lighter coagulated

particles and forming a stable floc

Electrocoagulation Targets

1. Coagulation of

suspended solids

2. Precipitation and

agglomeration of

dissolved metals

3. De-emulsification

of oil and grease

from water

Electrocoagulation

Electrocoagulation Process

Gravity Separation

Electrocoagulation Makes Particles

Larger

Coagulation of Suspended Solids

• Coagulation is one of the most

important physiochemical reactions

used in water treatment

• Coagulation is brought about by the

reduction of the net surface charge

where the colloidal particles (previously

stabilized by electrostatic repulsion) can

approach closely enough for Van Der

Waals forces to hold them together and

allow aggregation

Coagulation of Suspended Solids

• Coagulation can be achieved by

chemical or electrical methods

• Metals salts like Aluminum Sulfate and

Ferric Chloride have been used for

over 100 years in water treatment

• In the EC process, the coagulant is

generated in-situ by electrolytic

oxidation of an anode

• Ions are removed from water by

reacting other ions of opposite

charges, or through floc of metallic

hydroxides generated within the

effluent

Electrocoagulation

Chemical Treatment

“Alum, lime and/or polymers…tend to generate

large volumes of sludge with high bound water content that

can be slow to filter and difficult to dewater. These treatment

processes also tend to increase the total dissolved solids (TDS)

content of the effluent, making it unacceptable for reuse within

industrial applications.”*

*Benefield, Larry D.; Judkins, Joseph F.; Weand, Barron L. (1982). Process Chemistry for Water and Wastewater Treatment. Englewood Cliffs, NJ: Prentice-Hall. p. 212.**Woytowich, David L.; Dalrymple, C.W.; Britton, M.G. (Spring 1993). "Electrocoagulation (CURE) Treatment of Ship Bilge Water for the US Coast Guard in Alaska". Marine Technology Society Journal (Columbia, MD: Marine Technology Society, Inc.) 27 (1): 92.***MF Pouet, 1995

“The characteristics of the electrocoagulated flock differ

dramatically from those generated by chemical coagulation. An

electrocogulated flock tends to contain less bound water, is more shear

resistant and is more readily filterable.”**

Literature

Project Background

• Nevada Profile II standards introduction

Analytical Parameter

Description

Units Limit Value

Aluminum mg/L 0.2

Antimony mg/L 0.006

Arsenic mg/L 0.010

Barium mg/L 2.0

Beryllium mg/L 0.0004

Cadmium mg/L 0.005

NV Profile II Standards (cont.)


Description

Units Limit Value

Chloride mg/L 400

Chromium mg/L 0.1

Copper mg/L 1.0

Fluoride mg/L 4.0

Iron mg/L 0.6

Lead mg/L 0.015

Magnesium mg/L 150

Manganese mg/L 0.10



Description

Units Limit Value

Mercury mg/L 0.002

Nickel mg/L 0.1

Nitrate + Nitrite (as N) mg/L 10

Nitrogen, Total (as N) mg/L 10

pH (standard units) s.u. 6.5 – 8.5

Selenium mg/L 0.05

Silver mg/L 0.1

Sulfate mg/L 500



Description

Units Limit Value

Thallium mg/L 0.002

Total Dissolved Solids mg/L 1,000

WAD Cyanide mg/L 0.2

Zinc mg/L 5.0

Note: All analyses for the dissolved fraction.

Targets: Arsenic and Antimony

• Dissociation of Arsenite [As(iii)]

Targets: Arsenic and Antimony (cont.)

• Dissociation of Arsenate [As(v)]

ARSENIC PRECIPITATION

As(iii) Fe3+

Arsenic (III)

No Attraction

OCL-

Oxidation

As(iii) As(v)

Created

Negatively

Charged As (V)

Fe3+

Arsenic (V)Attracted and

Bound to

Ferric

Precipitate

As(v)

PERIODIC TABLE

ARSENIC POURBAIX DIAGRAM

Arsenic (v)

Arsenic (iii)

ANTIMONY POURBAIX DIAGRAM

Antimony (v)

Antimony (iii)

FERRIC CHLORIDE COAGULATION

Fe3+

Lot’s of Competition

CL-

Fe3+

CL-CL-

CL-

CL-

CL-

CL-

CL-

CL-

Fe3+As(v)

-

As(v)-

As(v)-

OH-

OH-

OH-

OH-

OH-

OH-

OH-

OH-

EC COAGULATION

Fe3+

Less Competition, Higher Potential Energy

Fe3+

Fe3+ As(v)-

As(v)-

As(v)-

An

ode

+

Cath

ode

OH-H2

H2

H2

OH-

OH-

OH-

OH-

OH-

Treatment

Methods• Untreated raw influent

• Aerated and ORP raised

with EOX

• EC cell treatment,

settling, and filtration

Site Characteristics

• Mine Water Sample #1

• Mine surface water/rain simulated stormwater mix

• Elevated arsenic and antimony


• Mine water storage pond

• Elevated arsenic, antimony, and thallium


• Mine water storage pond

• Elevated arsenic, antimony, aluminum, iron, sulfate,

thallium, and pH level

Sample #1 ResultsParameter

Description

Units NV PII Influent Effluent

Aluminum mg/L 0.2 ND<0.2 ND<0.2

Antimony mg/L 0.006 0.017 ND<0.005

Arsenic mg/L 0.010 1.5 ND<0.003

Barium mg/L 2.0 ND<0.05 ND<0.05

Beryllium mg/L 0.0004 ND<0.004 ND<0.004

Cadmium mg/L 0.005 ND<0.004 ND<0.004

Chloride mg/L 400 14 170

Chromium mg/L 0.1 ND<0.01 ND<0.01

Sample #1 Results (cont.)Parameter

Description


Copper mg/L 1.0 ND<0.02 ND<0.02

Fluoride mg/L 4.0 0.15 0.13

Iron mg/L 0.6 ND<0.56 ND<0.56

Lead mg/L 0.015 ND<0.015 ND<0.015

Magnesium mg/L 150 3.5 3.5

Manganese mg/L 0.10 ND<0.011 ND<0.011

Mercury mg/L 0.002 ND<0.0005 ND<0.0005

Nickel mg/L 0.1 ND<0.05 ND<0.05


Description

Units NV

PII

Influent Effluent

Nitrate+Nitrite (N) mg/L 10 0.49 0.52

Nitrogen, Total (N) mg/L 10 1.08 0.94

pH (standard

units)

s.u. 6.5-

8.5

7.45 6.57

Selenium mg/L 0.05 ND<0.005 ND<0.005

Silver mg/L 0.1 ND<0.02 ND<0.02

Sulfate mg/L 500 150 150

Thallium mg/L 0.002 ND<0.002 ND<0.002


Description

Units NV

PII

Influent Effluent

Total Dissolved

Solids

mg/L 1,000 250 400

WAD Cyanide mg/L 0.2 ND<0.005 ND<0.005

Zinc mg/L 5.0 ND<0.05 ND<0.05


Description

NV PII Influent Effluent

Lab #1

Effluent

Lab #2

Aluminum 0.2 0.09 ND<0.056 0.0126

Antimony 0.006 0.03 0.0042 0.0053

Arsenic 0.010 0.28 ND<0.003 0.0021

Barium 2.0 0.0959 0.0810 0.0789

Beryllium 0.0004 ND<0.0014 ND<0.0014 ND<0.0014

Cadmium 0.005 ND<0.0002 ND<0.0002 ND<0.0002

Chloride 400 69.9 190 204.4

Chromium 0.1 ND<0.0006 ND<0.0006 ND<0.0006

Copper 1.0 0.0034 0.078 0.0069

Fluoride 4.0 0.5 ND<0.02 ND<0.02


Description


Lab #1

Effluent

Lab #2

Iron 0.6 0.27 0.20 0.25

Lead 0.015 0.052 0.0056 0.0047

Magnesium 150 30.1 27.4 30.3

Manganese 0.10 0.047 0.076 0.079

Mercury 0.002 ND<0.0001 ND<0.0001 ND<0.0001

Nickel 0.1 0.0066 0.0028 0.0208

Nitrate+Nitrite (N) 10 0.05 ND<0.02 ND<0.02

Nitrogen, Total (N) 10 0.69 0.72 1.37

pH (standard units) 6.5-8.5 8.22 6.96 7.29

Selenium 0.05 0.0046 0.0106 0.0086


Description


Lab #1

Effluent

Lab #2

Silver 0.1 ND<0.0002 ND<0.0002 ND<0.0002

Sulfate 500 61 59.6 55.7

Thallium 0.002 0.0025 ND<0.002 ND<0.002

Total Dissolved

Solids

1,000 403 590 585

WAD Cyanide 0.2 ND<0.005 ND<0.005 ND<0.005

Zinc 5.0 0.0556 0.0569 0.0571


Description


Aluminum mg/L 0.2 11 ND<0.11

Antimony mg/L 0.006 0.059 0.0058

Arsenic mg/L 0.010 6.3 ND<0.0033

Barium mg/L 2.0 0.23 0.1100

Beryllium mg/L 0.0004 ND<0.002 ND<0.002

Cadmium mg/L 0.005 ND<0.004 ND<0.004

Chloride mg/L 400 47 53

Chromium mg/L 0.1 0.017 ND<0.010


Description


Copper mg/L 1.0 ND<0.020 ND<0.020

Fluoride mg/L 4.0 0.55 NS

Iron mg/L 0.6 7.4 ND<0.050

Lead mg/L 0.015 0.0055 ND<0.001

Magnesium mg/L 150 17 12

Manganese mg/L 0.10 0.13 ND<0.010

Mercury mg/L 0.002 0.0075 ND<0.0005

Nickel mg/L 0.1 0.05 ND<0.050


Description


Nitrate+Nitrite (N) mg/L 10 <0.02 <0.02

Nitrogen, Total (N) mg/L 10 0.246 NS

pH (s.u.) s.u. 6.5-8.5 9.29 6.64

Selenium mg/L 0.05 ND<0.025 ND<0.025

Silver mg/L 0.1 ND<0.020 ND<0.020

Sulfate mg/L 500 590 470

Thallium mg/L 0.002 0.0087 ND<0.0019

TDS mg/L 1,000 810 790


Description


WAD Cyanide mg/L 0.2 ND<0.005 ND<0.005

Zinc mg/L 5.0 0.055 ND<0.050

Conclusions

• Increasing challenges in mine wastewater

• New approaches must target multiple pollutants

• EC advantages

• Full compliance demonstrated

• Breadth of pollutants targeted

• Lack of trade-offs with other contaminants

Documents

MEETING NEVADA DEP-BMRR PROFILE II PARAMETERS WITH ... · meeting nevada dep-bmrr profile ii parameters with electrocoagulation based treatment solutions b. denney eames, bryan nielsen,