CYANIDE

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BAPPG CYANIDE PRESENTATION
Team Cyanide
Fact Sheet:
Sarah Scheidt, City of Sunnyvale
Presentation:
Norm Domingo, SBSA
Michael Dunning, USD
BAPPG PRESENTATION OUTLINE: CYANIDE
INTRODUCTION:
The goal of this presentation will be to:
• Identify industrial sources of Cyanide to the influent of San
Francisco Bay Area Wastewater Treatment Plants.
• Explain how Cyanide is used in these industrial sources.
• Explain treatment methodologies
• Explain analysis methods
• Identify industrial Cyanide discharge regulatory requirements
• Identify RWQCB Cyanide discharge requirements for POTWs
PRESENTATION OULTINE
I)
Define Cyanide
II)
Identify Industrial Users
III)
Treatment methodologies
IV)
Analytical Methods
VI)
Identify RWQCB discharge requirements for POTWs
CYANIDE
CN , (C≡N) , –C≡N
Chemical Structure
A cyanide is any chemical compound that
contains the cyano group (C≡N), which
consists of a carbon atom triple-bonded to a
nitrogen atom. Inorganic cyanides are
generally salts of the anion CN−. Organic
compounds that have a –C≡N functional group
are called nitriles. Of the many kinds of
cyanide compounds, some are gases; others are
solids or liquids. Those that can release the
cyanide ion CN− are highly toxic to animals.
INORGANIC FORMS
• Two basic forms
• Simple Cyanides represented by the formula:
A(CN)X where A is an alkali (sodium,
potassium, ammonium) and X is the valence of
A.
• Complex Cyanides represented by the formula:
AYM(CN)X where A represents the alkali
present Y times, M the heavy metal (iron,
cadmium, copper) and X the number of
cyanide groups.
ORGANIC FORMS
• Organic compounds that have a cyanide
functional group are called NITRILES
• An example of a nitrile is CH3CN, acetonitrile
(ethanenitrile per IUPAC), also known as methyl
cyanide.
• Nitriles do not release cyanide ions.
• A functional group with a hydroxyl and cyanide
bonded to the same carbon is called cyanohydrin,
and cyanohydridins are hydrolyzed into hydrogen
cyanide and a carbonyl compound (ketone or
aldehyde).
FUN FACTS
• Cyanides are produced by certain bacteria, fungi, and algae and are
found in a number of foods and plants. Cyanides are found, although
in small amounts, in certain seeds and stones, e.g. those of apple,
mango, peach, and bitter almonds.[5] In plants, cyanides are usually
bound to sugar molecules in the form of cyanogenic glycosides and
defend the plant against herbivores. Cassava roots (also called
manioc), an important potato-like food grown in tropical countries
(and the base from which tapioca is made), also contain cyanogenic
glycosides.[6][7]
• The cyanide radical CN· has been identified in interstellar space.[8]
• Hydrogen cyanide is produced by the combustion or pyrolysis of
certain materials under oxygen-deficient conditions. For example it
can be detected in the exhaust of internal combustion engines and
tobacco smoke. Certain plastics, especially those derived from
acrylonitrile, release hydrogen cyanide when heated or burnt.[9]
TOXICITY
• Cyanide is a rapidly acting, potentially deadly chemical that
can exist in various forms.
• Cyanide can be a colorless gas, such as hydrogen cyanide
(HCN) or cyanogen chloride (CNCl), or a crystal form such as
sodium cyanide (NaCN) or potassium cyanide (KCN).
• Cyanide sometimes is described as having a “bitter almond”
smell, but it does not always give off an odor, and not
everyone can detect this odor.
TOXICITY
• Many forms of cyanide are toxic to humans. Toxicity can be
attributed to interactions with low pH (acidic) solutions and some
biological systems to produce hydrogen cyanide.
• Most of the inorganic salts have exposure limits of a few parts per
million. Exposure can occur by absorption through the skin, by
inhalation of dusts or gas, or by ingestion. Exposure to minor
amounts of cyanide on the skin can result in dermatitis.
• Certain species of fish are extremely sensitive and can be killed by
low levels of cyanide (US EPA, 1979). Bluegill, salmon and trout are
killed by levels slightly over 0.1 ppm cyanide. Compound levels
below 0.1 ppm can functionally effect metabolic and reproductive
cycles. Cyanide levels that kill fish often do not adversely impact
lower aquatic organisms like crustaceans and mussels.
• Toxicity may extend to microorganisms that digest sewage and
sludge.
Table 3. Toxicity of Cyanide Compounds
NAME/FORMULA
PHYSICAL FORM
TLV
LD50
HYDROGEN
CYANIDE (HCN)
GAS
5mg/m3
1mg/kg human
POTASSIUM
CYANIDE (KCN)
SOLID
5mg/m3
2.85 mg/kg
human
SODIUM CYANIDE
(NaCN)
SOLID
5mg/m3
2.85 mg/kg
human
• Sources: (Sax, Merck)
• TLV threshold limit value is the time time-weighted average
concentration for an 8-hour workday and 40-hour workweek to
which a worker may be repeatedly exposed without adverse effect.
• LD50 lethal dose to 50% of a specified population.
SAFETY
• The most dangerous cyanides are hydrogen cyanide (HCN)
and salts derived from it, such as potassium cyanide (KCN)
and sodium cyanide (NaCN), among others.
• If accidentally ingested (swallowed), chemicals found in
acetonitrile based products that are used to remove artificial
nails can produce cyanide.
SAFETY
The hazards associated with cyanide use cannot be minimized;
however, the risks can be reduced through safe handling practices.
Cyanide safety procedures should include instructions for:
• chemical storage
• Containment
• piping, transportation
• handling, use
• protective equipment
• personal hygiene
• monitoring and emergency contingencies
• All personnel who are exposed to cyanide, including contractors
and visitors, should receive appropriate training.
SAFETY GUIDELINES
• Managing cyanide safely requires effective segregation of cyanide
solutions. The accidental mixing of acids with cyanide causes a
reaction that can quickly release dangerous amounts of hydrogen
cyanide gas.
• Handling of solids should be limited to trained personnel, and
solutions should be prepared in areas with adequate ventilation to
prevent exposure to dust. Use of dust masks is recommended.
• Safe cyanide handling requires careful attention to personal hygiene.
Workers must avoid skin and eye contact through the use of
protective clothing and equipment. Ideally, workers should shower
and change clothes at the end of the work shift and workers should
always wash up before handling food or other items. Exposure to
small amounts of cyanide over a period of time can result in
dermatitis.
SAFETY
• Air agitation of cyanide solutions should be avoided
because it causes misting and carbon dioxide in the air
is acidic enough to liberate hydrogen cyanide.
• Alkaline chlorination treats cyanide wastewater. A
residual concentration of free chlorine will be present
after treatment, and it is important that the residual be
reduced. If chlorine gas is used an excessive
concentration of chlorine can result in the release of
chlorine gas during pH adjustment. Other sources of
Cl2, such as sodium hypochlorite, may be safer.
USES
Cyanide has many industrial and commercial
uses. It is used in industry for mining, metal
finishing,
medical
applications
and
pharmaceutical manufacturing.
Commercial businesses such as printers have it as
a component of their inks. Pest companies use it
as a pesticide and algaecide. It is used by fishing
poachers to capture tropical fish near live coral
reefs for the aquarium and seafood markets.
Jewelers may have small quantities on site.
MEDICAL USE
• The cyanide compound sodium nitroprusside is occasionally
used in emergency medical situations to produce a rapid
decrease in blood pressure in humans; it is also used as a
vasodilator in vascular research. The cobalt in artificial
Vitamin B12 contains a cyanide ligand as an artifact of the
purification process. During World War I, a copper cyanide
compound was briefly used by Japanese physicians for the
treatment of tuberculosis and leprosy.[12]
• It is used in pharmaceuticals such as the anti cancer drug
laetrile. Also in surgical dressings that foster healing and
reduce scarring.
SOURCES
• There are three main wastewater sources of Cyanide. They
are industrial, commercial and residential.
• Cyanide is naturally present in some foods and in certain
plants such as cassava. Cyanide is contained in cigarette
smoke and the combustion products of synthetic materials
such as plastics. Combustion products are substances given
off when things burn.
• In manufacturing, cyanide is used to make pharmaceuticals,
paper, textiles, and plastics. It is present in the chemicals
used to develop photographs. Cyanide salts are used in
metallurgy for electroplating, metal cleaning, and removing
gold from its ore. Cyanide gas is used to exterminate pests
and vermin in ships and buildings.
INDUSTRIAL SOURCES
The biggest source of Cyanide in the SBSA
service area, as is for other POTWs, is from
Metal Finishers.
Industrial use of Cyanide is also regulated at
Centralized
Waste
Treatment
and
Pharmaceutical facilities.
CENTRALIZED WASTE TREATMENT
METAL FINISHERS
Electroplating
PLATING SHOP TANK LAYOUT
PROCESS SCHEMATICS
TREATMENT
TREATMENT AREA
SEGREGATED PLATING AREA
TREATMENT BY CHLORINATION
HCN MONITORING
ALARM SET POINTS
• 2 PPM HCN SETS OFF
ROOM ALARM
• 10 PPM BUILDING
EVACUATION ALARM
AND ALARM TO FIRE
DEPARTMENT
AREAS MONITORED
• 3 AREAS MONITORED
• PLATING ROOM
• BY CONTROL PANEL
LOCATED OUTSIDE THE
PLATING ROM
• ROOF VENT FROM THE
PLATING ROOM
METAL FINISHING
BEST MANAGEMENT PRACTICES
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Develop a cyanide management plan, and integrate it with the facility environmental and
safety management plan.
Establish initial and refresher cyanide management training for managers, workers and
contractors.
Establish well-defined personnel responsibilities and clear chains of command for cyanide
use and management.
Develop safe procedures for handling cyanide, i.e., storage, transportation, containment, spill
management, production processes, raw material additions, solution sampling and analysis,
solution maintenance, waste treatment, waste disposal and equipment maintenance.
Develop rinsewater quality standards for all cyanide processes and pre-cyanide processes.
Generally 5 ppm is a reasonable rinsewater standard for a final cyanide process rinse.
Develop and implement an integrated pollution prevention strategy encompassing point
source waste minimization, recovery, and recycling, waste treatment and off-site disposal.
Conduct regular cyanide audits, with corrective action, and update the cyanide management
plan on a regular basis.
Maintain primary containment tanks, drums, piping, valves, pumps and other equipment to
prevent leaks and spills.
Segregate cyanide processes, pretreatment, storage and other operations from non-cyanide
operations in a separate secondary containment system.
BMPs
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Store cyanide-based raw materials in a secure, dry and ventilated storage area.
Monitor work areas for hydrogen cyanide and wastewater treatment areas for
hydrogen cyanide and cyanogen chloride
Ventilate all cyanide process, wastewater treatment and storage areas
Provide workers and visitors with proper protective equipment including gloves,
aprons, face shields, goggles, safety glasses, respirators and other protective
clothing.
Provide workers and visitors with access to lavatories and showers to maintain
appropriate personal hygiene.
Dispense and weigh raw materials in a ventilated area.
Develop and practice emergency procedures for cyanide spills.
Develop and practice emergency procedures for human exposure (skin, eye,
ingestion) to cyanide mists and fumes.
Use the minimum amount of cyanide required for adequate process or operation.
Avoid air agitation of cyanide solutions as carbon dioxide can liberate hydrogen
cyanide.
Alternatives to Cyanide
Non-cyanide Plating Processes
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Metal
Brass
Bronze
Cadmium
Copper
Gold
Indium
Silver
Zinc
Cyanide
Proven
Proven
Proven
Proven
Proven
Proven
Proven
Proven
Non-cyanide
No
No
Yes
Proven*
Developing
Yes
Developing
Proven
* New alternatives in development for specific cyanide processes.
Alternatives
Non-cyanide process alternatives provide
surface finishing facilities with significant
advantages
in
specific
circumstances.
However, non-cyanide processes are often
more difficult to treat in conventional
wastewater treatment systems, more difficult
to recover or recycle and are, generally, more
difficult to control.
Analysis
• All wastewater sampling and analysis is
required to be performed in accordance 40
CFR 136.
• Sampling : Grab, dark amber glass/plastic,
NaOH
• Analysis: Total Cyanide
Cyanide Amenable to Chlorination
Regulated by Federal, State and Local Regulations.
http://www.dtsc.ca.gov/HazardousWaste/Cyanide/index.cfm#Permit_by_Rule:
_Treatment_for_Aqueous_Waste_Containing_Cyanide
• Permit by Rule: Treatment for Aqueous Waste Containing Cyanide
The following are highlights of the new regulations for Permit by
Rule for Aqueous Waste Containing Cyanide. Please refer to the
Permit by Rule fact sheet or the regulations for more details.
• New Permit by Rule Eligible Treatment Methods for Aqueous
Waste Streams Containing Cyanide
• 1. oxidation by addition of hypochlorite;
• 2. oxidation by addition of peroxide or ozone, with or without the
use of ultraviolet light;
• 3. alkaline chlorination;
• 4. electrochemical oxidation;
• 5. ion exchange; or
• 6. reverse osmosis.
RWQCB REQUIREMENTS
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Cyanide Site Specific Objectives and Cyanide Action Plan Fact Sheet
Resolution R2-2006-0086 – To amend the Water Quality Control Plan (Basin Plan) for the San Francisco
Bay Region to adopt Site-Specific Objectives for Cyanide for San Francisco Bay and an Implementation
Plan. The Basin Plan requires cyanide source control programs, or “Cyanide Action Plans”, as incorporated
into municipal NPDES Permit provisions. Dischargers shall implement monitoring and surveillance,
pretreatment, source control and pollution prevention for cyanide in accordance with the following tasks:
Cyanide Action Plan Task
Additional Resource / Reference
Task (1) Review Potential Cyanide Contributors The Discharger shall submit an inventory of potential contributors of cyanide to the wastewater treatment
facility (e.g., metal plating operations, hazardous waste recycling, etc.). If no contributors of cyanide are
identified, Tasks 2 and 3 are not required, unless the Discharger receives a request to discharge detectable
levels of cyanide to the sanitary sewer. If so, the Discharger shall notify the Executive Officer and
implement Tasks (2) and (3). Compliance Date December 1, 2009
Task (2) Implement Cyanide Control Program
The Discharger shall submit a plan for, and begin implementation of, a program to minimize cyanide
discharges to the sanitary sewer system consisting, at a minimum, of the following elements: Compliance
Date February 28, 2010 with 2009 annual P2 report
i. Inspect each potential contributor to assess the need to include that contributing source in the control
program.
ii. Inspect contributing sources included in the control program annually. Inspection elements may be based
on USEPA guidance, such as Industrial User Inspection and Sampling Manual for POTWs (EPA 831-B-9401).
Cyanide Control Plan
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Review POTW Influent Data
Review Pretreatment Program Significant and Categorical Industrial User, and Commercial / Industrial User
Inventories
Pretreatment Inspections and regulations cover Action Plan requirements for inspections.
Review sanitary sewer trunk line monitoring data for commercial, industrial, and residential service areas.
BAPPG P2 and the Cyanide SSO Presentation August 2008 by Betsy Elzufon
BAPPG Factsheet on Approaches to Pollution Prevention for Cyanide – August 2008
City of San Jose Cyanide Fact Sheet
BAPPG Presentation Cyanide; 6/2/2010
iii. Develop and distribute educational materials to contributing sources and potential contributing sources
regarding the need to prevent cyanide discharges.
Wastewater Discharge Permits
DTSC Fact Sheets January 2002, 1) Jewelry Manufacturing Pollution Prevention Recommendations; and 2) Cyanide
Waste Produced in Jewelry Manufacturing
iv. Prepare an emergency monitoring and response plan to be implemented if a significant cyanide discharge
occurs.
v. If ambient monitoring shows cyanide concentrations of 1.0 μg/L or higher in the main body of San Francisco
Bay, undertake actions to identify and abate cyanide sources responsible for the elevated ambient concentrations.
BAPPG Cyanide SSO / Action Plan Fact Sheet with ERP Fact Sheet 6/2/2010.
Regional Monitoring Program (RMP) through BACWA
Task (3) Report Status of Cyanide Control Program
Submit a report to the Regional Water Board documenting implementation of the cyanide control program.
Compliance Date Annually with P2 reports due February 28.
POTW Annual Pollution Prevention Reports:
Cyanide Monitoring and Emergency
Response Plan Fact Sheet
• The Basin Plan Cyanide Site Specific
Objectives require POTWs to prepare an
emergency monitoring and response
plan that will be implemented if a
significant cyanide discharge occurs.
• Purpose is to respond to illicit
discharges
Potential Monitoring and Emergency Response Plan Contents
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POTW influent monitoring, typically per NPDES Permit influent and effluent monitoring
requirements.
Agency should define what a “significant discharge” of cyanide means as it pertains to influent or
effluent monitoring data. This could be done by creating performance based limit for cyanide using
existing cyanide data.
When significant discharge occurs take another effluent sample and an influent sample.
Sanitary sewer surveillance monitoring at a specified frequency for a number of trunkline,
commercial, and residential area sites. One example would be monitoring quarterly at seven sewer
trunkline locations, three commercial area locations and three residential area locations. The seven
trunkline locations are the same every quarter. The commercial and residential sampling locations
change every quarter.
If any of the sampling results for cyanide are detectable, the POTW will sample the same location
the next quarter.
In addition when cyanide is detected from trunkline, commercial or residential surveillance, the
Pretreatment Inspectors will audit the area to determine if there are any potential sources of cyanide.
If there are any potential industrial or commercial sources in the area they will be inspected.
Contact all potential cyanide sources and discuss any recent activities that could have caused high
value.
Investigate suspected cyanide dischargers that may have contributed to high value include review
of delivery, use, and shipment of cyanide.
Develop procedures for follow-up sampling and enforcement response if an IU discharges above the
appropriate Federal categorical limits or local limits.
Ensure procedures are in the Pretreatment Program Enforcement Response Plan and the Pretreatment
Sampling Standard Operating Procedure (SOP).
Report all findings in SMR, or in a letter to Regional Board. Follow up actions, and summarized
program results will be reported in the Annual Pollution Prevention Report.
Ambient San Francisco Bay
Monitoring
• Cyanide SSO resulted in NPDES Permit language stating:
• “If ambient monitoring shows cyanide concentrations of 1.0 ug/L or
higher in the main body of San Francisco Bay, undertake actions to
identify and abate cyanide sources responsible for the elevated
ambient concentrations.”
• Most agencies are participating in the Regional Monitoring Program
(RMP) through BACWA. The RMP has been tasked with sampling
the San Francisco Bay for cyanide and compiling the data for
BACWA.
• If the RMP ambient monitoring cyanide concentrations are equal to
or greater than 1.0 ug/L, agencies will compile and review their
effluent cyanide data to determine if the POTW could potentially be
a source responsible for the elevated ambient concentrations.
• Agencies will also work through BACWA to undertake actions on a
regional level to identify and abate cyanide sources responsible for
the elevated ambient concentrations.
References
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Capsule Report, Managing Cyanide in Metal Finishing, EPA 625/R99/009December 2000
Pollution Prevention for the Metals Finishing Industry - A Manual for Pollution
Prevention Technical Assistance Providers
Permit By Rule - Management of Aqueous Waste Containing Cyanide
WIKIPEDIA
THANKS TO:
INDUSTRIAL PLATING CO. IN SAN CARLOS, CA
SLAC , NATIONAL ACCELERATOR LABORATORY IN MENLO PARK, CA
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