ADDITIVES Can effectiveness be standardized? T. D. Ellison

Transcription

1 ADDITIVES Can effectiveness be standardized? T. D. Ellison 1

2 The question was asked by Prof. Mike Hoover, University of South Carolina to the NSF International Joint Committee on Wastewater Treatment Technology in 2010; He and others published research reports in the Journal of Environmental Health, in December 2011; 3 products tested in 20 tanks: poorly maintained, intermediately maintained and well-maintained tanks. Findings: No effects on poorly or intermediately maintained tanks; In well-maintained tanks, 2 reduced sludge levels, one with reduced effluent BOD5 One with no increase in effluent BOD5 or TSS 2

3 After many reviews a Task Group of the JC was set up in 2013 to attempt to answer it. Barely 50% of the JC thought it worthwhile pursuing. Initially there were two draft standards: Safety Efficiency Now, a combined standard in 2 parts. Safety a mandatory first step. 3

4 Objective of NSF JC WWT Task Group Produce a standard that enables the performance of additives to be demonstrated at a reasonable certification cost. 4

5 SCOPE Criteria and requirements for assessing the safety of wastewater additives intended for use in wastewater treatment systems and their effectiveness in promoting biological reactions. 5

6 State and Provincial Regulation Over 30 US States publish a list of approved additives; All State lists caution that approval only implies that the additive is safe to use; EPA s Safer Choice Program has only 2 products listed in the Biological-based products : Septic system treatments category CLR business and CLR home; No Canadian jurisdictions publish such lists. 6

7 Canadian Background-Sanitary Services Latest detailed data 2011 only: 80% had sewer connections 14% had a private septic system 1% were connected to a communal system 5% did not provide information In 2011, the population was million: 27.5 million connected to sewers 4.8 million had a private septic or communal system Assume = 1.5 million residences. This does not include seasonal access to cottages, etc. primarily with septic systems. 7

8 Canadian Background Rough residential market size (1.5 m properties): Once a year dose by 1/3rd of residences: 500,000 units sold Monthly dose by 10% of residences: 1,500,000 units sold Three times a year dosage by 50% the residences 2,250,000 units sold There are more than 15 Additives sold in Ontario. 8

9 Typical products Septic Drain Field Repair Kit 1 Case Septic Drainer 1 Quart Bio-Septic Boost $ (Plus S/H) For a failed septic system add 4 Gallons of Septic Drainer to the septic tanks outgoing drain or leach field or the distribution box or directly in the cesspool or drywell. Be sure to have the tank pumped along with the distribution box, be sure to remove debris from the drain lines or cesspool and drywell before applying Septic Drainer. Add in Bio-Septic Boost to increase the metabolic reproductive rate of naturally occurring bacteria by a million fold. 9

10 Typical products 1 QUART BIO-SEPTIC BOOST $59.99 Bio-Septic Boost increases the metabolic reproductive rate of naturally occurring bacteria by a million fold. Reduces grease, sludge and odours. 10

11 Typical products Pour & Go product works instantly Begins to biodegrade grease and organic matter the minute it reaches the septic tank Can also be used as a drain opener and in boat and RV holding tanks EPA's DFE formula for safer chemistry Eco-friendly formula From Amazon.com CDN$ CDN$ shipping Usually ships within 4 to 5 days. 11

12 Typical products Formulated in conjunction with the Environmental Protection Agency - uses only environmentally friendly ingredients Does not contain any soaps, enzymes or emulsifying ingredients Use in any drain or toilet Goes to work instantly to biodegrade grease and organic matter Restores the precise stability of healthy bacteria Canadian Tire: Regular Price: $8.99 Home Depot: Regular Price: $

13 Additive are heavily promoted on TV Ads FAQ from the CLR website: Is CLR safe for septic tanks? Use in septic systems up to 1,500 gallons. Shake before use. Using the measuring window on the side of the bottle, pour 1/3 of the bottle directly into any toilet or drain line monthly. CLR Septic System Treatment is safe on pipes and porcelain and works on fats, oils, grease and other stubborn organic matter. Does it work? This question is not offered. 13

14 However: Scientific Studies Kansas State University and Agricultural Experiment Station and Cooperative Extension Service findings: This research has found no benefit in septic tank function to using any type of septic system additives. In fact, some additives potentially could be detrimental to the function or components of the septic system or to groundwater quality. 1 One research study, for example, found that the use of a biological additive caused the solid sludge layer at the bottom of the septic tank to decompose too rapidly. This led to rapid gas production

15 However: Scientific Studies Studies from Purdue University 4 and Baylor University 5 concluded that: the addition of an aeration system to a septic tank improved the over all system operation and prevented early septic system failures %20Univ 15

16 Canadian Market Value Based on CLR retail price at $9.00: Once a year dose by 1/3rd of residences: 500,000 units sold - $4,500,000 Monthly dose by 10% of residences: 1,500,000 units sold - $13,500,000 Three times a year dosage by 50% of the residences 2,250,000 units sold - $20,250,000 And no clinical proof they work! 16

17 NSF 409 conceptual structure Provide a simple but effective certification standard; Field trial certification likely to be too expensive to induce certification requests; Field trial certification not necessarily replicable; Question: Could this be done as a laboratory test with controlled conditions? 17

18 SAFETY ASPECT Manufacturer s Declaration of ingredients and raw materials complete product composition including all intentionally added ingredients; reaction process of the additive once introduced; bacterial genus, species, strain accession number (if applicable and available); synonyms, common names, and superseded names; known residuals or suspected impurities if present at greater than 0.05% by weight. A 100% MSDS will suffice. 18

19 Safety Review Two methods: Literature review; Chemical Analysis as required. Leading to assessment that the product is either: safe to use, or not safe to use. 19

20 SAFETY to be declared safe to use must meet all three conditions: Public health No prohibited or restricted substances as declared in state or federal legislation. Environmental Health EPA-821-R Short-term methods for estimating the chronic toxicity of effluents and receiving waters to freshwater organisms. When tested at the recommended dosage must show an LC50 below regulated limits Protection of Infrastructure Absence of ingredients that would adjust the ph of the effluent to below 6.0 or above 8.0. EPA-8260 Volatile Organic Compounds by Gas Chromatography/Mass Spectrometry (GC/MS) any concentration less than 0.5 ug/l (ppb). 20

21 Effectiveness in use only if the product is safe to use General Test Method equipment L flasks without stoppers; 1 shaker table capable of rotational speeds between 10 and 100 rpm; an evaporating chamber; and a weigh scale. All of which are readily available. 21

22 Test Equipment 22

23 Test Equipment 23

24 Test Equipment 24

25 Effectiveness in use Two test Procedures for: Maintenance additives Additives intended to be used on a regular and continuing basis following the initial removal of sludges and FOG scums. Restorative additives Additives intended to be used to remove or diminish the levels of sludges and FOG scums existing in a non-regularly treated system. 25

26 Maintenance additives - Procedure Ambient temperature in the laboratory: 22 o C ± 2 o C; Tested wastewater taken from a municipal sewage plant prior to treatment; The CBOD 5, TSS and TKN levels of the wastewater used are recorded; 10 flasks will be filled with 2 L of the wastewater; Eight of the 10 flasks shall be dosed with the additive according to manufacturers recommendations; Flasks to be mounted on shaker table(s), set to rotate at 20 rpm; Rotation continues for 28 days; On the 15 th day of the test, a sample of the liquid in the flasks shall be taken and analyzed for the presence of the active ingredient; On the 28 th day, the liquid from each flask will be analyzed to determine the level of the active ingredient and the CBOD 5, TSS and TKN levels of the liquids in the control and test flasks separately. 26

27 Maintenance additives Pass Fail Additive concentration on day 15 shall be less than dose, and on the 28 th day, less than 10% of dose; On day 28, the CBOD 5, TSS levels in the test flasks shall both be lower than the levels recorded at the beginning of the tests and the levels in the control flasks; On day 28, the TKN levels shall be less than 40 mg/l; There shall be no visual evidence of the formation of sludge or scum in the test flasks. 27

28 Restorative additives - Procedure Ambient temperature in the laboratory 22 o C ± 2 o C; Tested wastewater taken from a municipal sewage plant prior to treatment; The CBOD 5, TSS and TKN levels of the liquid effluent used are recorded; 10 flasks will be filled with 500 ml of sludge taken from an anaerobic digester containing 6-8% solids and 1,500 ml of liquid effluent; Four additional 500 ml samples of the sludge will be dried in the evaporation chamber to determine the average dry mass of the solids contained; Eight of the 10 flasks shall be dosed with the additive according to manufacturers recommendations; Flasks shall be mounted on shaker table(s), set to rotate at 20 rpm; Rotation continues for 28 days; On the 15 th day of the test, a sample of the liquid in the flasks shall be taken and analyzed for the presence of the active ingredient; On the 28 th day, the liquid from each flask will be analyzed to determine the level of the active ingredient and the CBOD 5, TSS and TKN levels of the liquids in the control and test flasks separately; Any residual sludge in the test flasks will be evaporated and weighed. 28

29 Restorative additives Pass Fail Additive concentration on day 15 shall be less than dose, and on the 28 th day, less than 10% of dose; On day 28, the CBOD 5, TSS levels in the test flasks shall both be lower than the levels recorded at the beginning of the tests and the levels in the control flasks; On day 28, the TKN levels shall be less than 40 mg/l; The average dry mass of the sludge remaining in the test flasks shall be less than the average dry mass of the sludge remaining in the control flasks, and in any case less than the average dry mass of the sludge measured separately; There shall be no visual evidence of the formation of sludge or scum in the test flasks. 29

30 Product control, labelling and consumer information Standard requirements and language from NSF standards. 30

31 Current situation No agreement has been reached that NSF 409 is workable; Verification of the procedure is required; No additive manufacturers have indicated a willingness to subject their products to testing. 31

32 Questions Contact 32