Talk:Vermifilter

Application of standard headings?

Recommended that I apply the standard manual of style to the structure (table of content)? See here: https://en.wikipedia.org/wiki/Wikipedia:Manual_of_Style_(Sanitation)#Articles_on_technologies

Article needs images or schematics

Great to see this new article online now, well done! I think it urgently needs several images of schematics though so that people can picture what this is all about. Do you have any, User:Satchie12? EvMsmile (talk) 13:14, 18 August 2016 (UTC)

Proposed merge with Vermifiltration

I don't think we need two pages. Merge into the page on vermifilter. EvMsmile (talk) 21:59, 24 October 2016 (UTC)

• Merge. There is very little here anyway, not enough to warrant a separate article.--Gronk Oz (talk) 07:19, 25 October 2016 (UTC)

I'm improving the vermifiltration page. So I believe two pages will be okay since vermifiltration is the process and vermifilter is the system. — Preceding unsigned comment added by Noslenlou (talk • contribs) 12:03, 12 November 2016 (UTC)

I don't see the advantage of two separate pages. There is bound to be lots of overlap. What is your definition of "process" and "system" here and what's the advantage of having it as two separate pages? EvMsmile (talk) 15:05, 9 December 2016 (UTC)

• Merge. I think this will be clearer if described in a single page. No sense in repeating most of the information on both pages and having to keep both updated. Ajpolino (talk) 22:21, 9 December 2016 (UTC)
• Merge. I Agree. The system and process should be described together. Satchie12 (talk) 23:56, 14 December 2016 (UTC)

Done. EvMsmile (talk) 21:09, 3 January 2017 (UTC)

Unclear sentences in the lead

I don't find this sentence clear to lay people: is an aerobic treatment system comprising a passive aerobic biological reactor that treats wastewater by removing organic matter, pathogens and oxygen demand under a bio-oxidative process.

Problems:

• Mentions aerobic twice; once is enough.
• It does not remove all organic matter but only some; same applies to pathogens.
• Lay persons don't understand what "remove oxygen demand" means. This needs to be made clearer in the lead. There is an article on biological oxygen demand which you should link to (either here in the lead or later in the article)
• The term "bio-oxidative process" means nothing to a layperson. I would remove that here. If the term exists, then it should be on Wikipedia already, in which case we should link to it. If it doesn't exist yet on Wikipedia then it would need to be explained, but not right there at the beginning of the lead.
• My revision (which you reverted) tried to make it clearer that it is not just for wastewater but also for solid matter (i.e. fecal matter) - note the image in the lead also shows the process for excreta directly not for wastewater (wastewater is much more diluted); could mention and wikilink the term blackwater here. EvMsmile (talk) 00:35, 7 January 2017 (UTC)

Hi User:SatchieNZ, thanks for your improvements to the lead but my concerns are not fully addressed.

* "Removes" still makes it sound like all of it is removed which is not true.

Also this part here: that removes organic matter, pathogens and oxygen demand from wastewater. - BOD is a way to measure organic matter. Therefore, it is misleading to say it removes organic matter and BOD. You could say "reduces organic matter content as measured by the BOD of the wastewater". My fifth bullet point has also not been addressed yet. I would change it myself but I am scared that you would undo my change so I thought better to reach consensus on the talk page first. EvMsmile (talk) 20:39, 8 January 2017 (UTC)

Hi User:EvMsmile Regarding "removes": Try googling 'removal of biological oxygen demand'. Or you could have a look at this youtube video: https://www.youtube.com/watch?v=S0v2ycyjvWA or this one https://www.youtube.com/watch?v=SQR76d3PKrE

Sure, the consequence of removing organic matter is that the biological oxygen demand of the wastewater is reduced. Both are "removed", but one is a state and the other is a a process. "Removed" is not an absolute term, so is not misleading: Removal can be partial or full. Importantly there is a rate for removal of BOD, so its removal is beyond just removal of organic matter via filtration. Not all organic compounds are "organic matter" that can be physically filtered out of the water - biodegradeable wastewater organics include dissolved organic compounds and living bacteria in the water, thus not just degrading organics and filterable solids. That is, treatment is taking place in the water also, with oxygenation of the water influencing the rate of removal of oxygen demand, but not the organic matter directly like the filter process.

Regarding your fifth bullet point, you will see that the first sentence uses wastewater, because vermifiltration can even be used on petrochemical wastewater, so all encompassing. Then the second and third sentence use sewage and link to blackwater (a subset of wastewater) because this is what vermfilters are usually used for. I also mention fecal matter in the third paragraph. — Preceding unsigned comment added by SatchieNZ (talk • contribs) 05:48, 9 January 2017 (UTC)

I am hoping that others will also partake in this discussion in future as it will help us to get more opinions on what is clear and what is not clear. Basically, I worry that the text is not yet good enough to be understood by a lay person. Have you tried showing it to a Highschool Year 12 person? It should be understandable for someone at that level. Another good test is one's mother or mother-in-law. - Can we say something about how much removal is taking place? 50%? 90%? Not in the lead but in the main text. EvMsmile (talk) 20:38, 10 January 2017 (UTC)

I've just improved the lead section. In my view this is concise, clear and understandable for the layperson. Any words that the reader might not understand are linked to wikipedia pages if the reader requires clarification. SatchieNZ (talk) 06:41, 11 January 2017 (UTC)

Yes, the lead is taking shape. We should still get it checked with a layperson though. Well hopefully some other editors will join us eventually. Now the other thing that would be good is to make the lead more of a summary of the entire article, i.e. with some snippets of information from each section. The length of the lead can be up to 4 paragraphs, by the way. EvMsmile (talk) 20:52, 11 January 2017 (UTC)

Using simple, clear language

I am still looking through how to improve the language of the main text further. I came across this: "but with potentially higher hydraulic processing capacities". Can this please be clarified. What is it supposed to mean? Are we talking about space requirement? Hydraulic loading? Organic loading? I.e. kg BOD / m2 /d ? Please clarify this, thanks. EvMsmile (talk) 20:52, 11 January 2017 (UTC)

It's in the reference under Discussion - treatment efficiency. The paper is not very clear however in terms of comparing size. From the reference: "Higher hydraulic loading indicated more processing capacity of wastewater." The sentence in this article could be clarified to say "Vermifilters offer treatment performance similar to conventional decentralised wastewater treatment systems but with potentially higher hydraulic loading and wastewater processing capacities for the same land area.[2]" SatchieNZ (talk) 00:43, 12 January 2017 (UTC)

If we genuinely want non-technical people to be curious and interested in vermifiltration, I think we need a less technical opening paragraph. I'm new to this page, so didn't want to tinker without getting others' thoughts.

How about starting with: Put simply, the term "vermifilter" refers to the use of worms to filter out pathogens. Vermifiltration requires an aerobic environment because worms and other organisms that assist in vermifiltration need oxygen. The aerobic environment is created by............. The presence of oxygen enables............

I don't know what is meant by "passive biological reactor" or by "removal of.... oxygen demand from wastewater."

I'm proposing this article be written for an audience who doesn't yet even know that worms eat the stuff, process it in their gut, and excrete teeny tiny amounts of cleaner stuff, resulting in cleaner liquid.PlanetCare (talk) 15:06, 17 March 2017 (UTC)

I am all for simplifying language and writing for the lay person. But let's not use the words "put simply" ;-) I suggest you gently go ahead with your planned changes, saving frequently so that others watching the page can easily see the changes. EMsmile (talk) 13:20, 17 March 2017 (UTC)

I'm going to do a little more reading on the vermi-composting page, as it might be important to clarify the difference between processing solids and processing material that's mostly liquid. Agreed on the danger of ever saying "put simply." PlanetCare (talk) 15:04, 17 March 2017 (UTC)

Agree with your point but the subject is quite complicated. The worms don't actually eat the organics, they eat the bacteria that is eating the organics... certainly the liquid they excrete would be "cleaner" than what they ingest, but its a matter of putting it in simple terms that are not misleading. What does "cleaner" mean? Perhaps the first paragraph could simply state "...that produce humus and purify the wastewater. "SatchieNZ (talk) 19:08, 18 March 2017 (UTC)

Mentioning examples

I've added an examples section because I think it helps the reader to understand what this is all about. The first example I have added is the one on Tiger Toilets (there is also a redirect for the term Tiger Toilet to here; when the reader gets to this page they need to know why they have been redirected, so the term "tiger toilet" does need to appear in the article at least once). I would like to add more examples, whether they are "branded" or not does not matter. I don't think we need to differentiate exactly the technologies either. This is not a technical textbook but should just give the reader a general overview. When you look at the UDDT page in the examples section (https://en.wikipedia.org/wiki/Urine-diverting_dry_toilet#Examples) we do mention the name that they have chosen "ecoLay". Another example which is a bit different is this page, where company names are also mentioned: https://en.wikipedia.org/wiki/Female_urination_device#Female_urinals There is also an examples section on the composting toilet article (https://en.wikipedia.org/wiki/Composting_toilet#Examples). Note that any example provided should have a good solid reference to go with it. EvMsmile (talk) 21:02, 11 January 2017 (UTC)

Reference #10 is "The Potential of Subsurface Infiltration for the Treatment of Biofil Toilet Technology Effluent", there will be others on BioFil vermifilters. Also there is GSAP vermifilter which will have published papers. What comprises a 'good solid reference'? SatchieNZ (talk) 00:49, 12 January 2017 (UTC)

I think for the examples section we can pretty much use any reference we can get our hands on. But in general, we need to follow these guidelines: WP:RELIABLE and when it comes to health content: WP:MEDRS. One key consideration is that we are not meant to cite primary research articles. So quite a few of the articles in this vermifilter page are not according to the guidelines. We should improve on them over time. As this is a very practical topic there are however fewer publications available than for some of the other Wikipedia articles. So let's use whatever we have for now but keeping in mind that primary research papers are not ideal. Books, reviews and documents from e.g. WHO, UNICEF, WSP or alike are better if they are available. EvMsmile (talk) 15:23, 12 January 2017 (UTC)

Here are some commercial blackwater/greywater vermifilter products for you to add:

http://www.wormfarm.com.au http://www.zenplumb.com/onzite/ http://www.naturalflow.co.nz/ http://swwsnz.co.nz/ http://www.autoflow.net.nz/ Thats just some of them from Australia and New Zealand, the technology is not new and is available worldwide. Once you've included the appropriate information from each of these I'll give you more to add. There is also plenty available on GSAP and Biofil SatchieNZ (talk) 21:17, 12 January 2017 (UTC)

I've added a sentence. Would be good to add one or several references (ideally, e.g. a conference paper talking about several systems at once?); I am hesitant to put links to company websites (if someone wants, they can easily find them with Google once we have mentioned the names). We might need to group the examples by vermi-toilets (tiger toilet, GSAP, Biofil) and others (greywater, domestic wastewater)?EvMsmile (talk) 22:17, 12 January 2017 (UTC)

In my view you need to describe both the system and the countries. Primary and/or secondary treatment, greywater and blackwater, surface or subsurface... domestic/municipal. SatchieNZ (talk) 22:21, 12 January 2017 (UTC)

I don't understand what you mean? You could just go ahead and expand the examples section, then I will probably see what you mean. References will be needed though in any case (and not just the websites of the suppliers); also keeping in mind that we are writing for laypersons and not writing a new technical handbook or listing of all available suppliers. EvMsmile (talk) 23:12, 12 January 2017 (UTC)

Correct paragraphing in lead section

I'm not comfortable with the sentence/paragraph structure in the lead section. The second sentence is actually a different subject to the first sentence so should be a separate paragraph. The second sentence of the first paragraph is actually the same subject as the second paragraph. I originally had the second sentence of the first paragraph as the first sentence of the second paragraph and it seems to me that this is the way it should be. SatchieNZ (talk) 07:29, 17 January 2017 (UTC)

could be but overall I am actually still not happy with the lead at all. Remember the lead is the part of the article that would first be translated into another language (when people do article language translations). So it is really important. It should be a good summary of the article. See e.g. here for a good lead: https://en.wikipedia.org/wiki/Autism (this is a high quality article). The lead should be about 4 paragraphs long. Each paragraph around 4-6 lines (roughly). See here in the sources editor the hidden sub-headings in the lead: https://en.wikipedia.org/w/index.php?title=Autism&action=edit , e.g. <!-- Causes and diagnosis -->

So I would like to have a similar lead for this article. Therefore, if you move the second sentence of the first paragraph away, then what goes into its place? The first paragraph is then only one sentence long?? It would be great to have a really good lead section with 4 clear, easy to understand paragraphs which summarise all the different sections of the article. EvMsmile (talk) 21:08, 17 January 2017 (UTC)

Have had a first attempt at expanding the lead section. Undo this if it's not going in the right direction. We could discuss subjects for each paragraph... SatchieNZ (talk) 22:45, 17 January 2017 (UTC)

It's better but we could still do more. Yes, hidden paragraph headings in the lead are good to have. Each paragraph could be around 4-6 lines long. It's worth putting effort into the lead (and citations) as the lead is the first piece that would get translated in future, and it's also the first bit (and often the only bit) that people read... EvMsmile (talk) 21:35, 7 February 2017 (UTC)

Working on first paragraph of lead

I've had a go at making the first paragraph of the lead easier to understand. This is a really important paragraph as Google search results and Alexis will only bring this up in a box and many people won't read past that. Please check if it's correct and easy to understand? Is wood chips a good example for the filter media? User:PlanetCare and User:SatchieNZ.EMsmile (talk) 13:30, 13 April 2017 (UTC)

Sorry, but in my view the lead has been turned into a dogs breakfast. Its waffly, nondescript, has spelling errors and reads terribly:

A vermifilter (also called vermi-digester or many other names) is treatment system for organic waste or wastewater that uses an aerobic environment and earthworms. In the vermifilter reactor, organic matter and pathogens are removed from the wastewater. The organic matter content of the wastewater is commonly measued by its biological oxygen demand - which is lower after it has been treated in the vermifilter. Therefore, the treated wastewater is "cleaner". The reactor contains certain filter media, such as wood chips, that filters organic material from the wastewater and provides a habitat for earthworms. These earthworms produce humus in a composting process and purify the wastewater. The "trickling action" of the wastewater through the media also provides oxygen to the wastewater. 

It should be returned to:

A vermifilter (also called vermi-digester or many other names) is an aerobic treatment system comprising a passive biological reactor that removes organic matter, pathogens and oxygen demand from wastewater. This is achieved via media that filters organic material from the wastewater and provides a habitat for composting earthworms that produce humus. The trickling action through the media also oxygenates the wastewater.SatchieNZ (talk) 08:11, 15 April 2017 (UTC)

Sorry but please be more specific. What exactly is wrong with this?:

A vermifilter (also called vermi-digester or many other names) is treatment system for organic waste or wastewater that uses an aerobic environment and earthworms. In the vermifilter reactor, organic matter and pathogens are removed from the wastewater. The organic matter content of the wastewater is commonly measured by its biological oxygen demand - which is lower after it has been treated in the vermifilter. Therefore, the treated wastewater is "cleaner". The reactor contains certain filter media, such as wood chips, that filters organic material from the wastewater and provides a habitat for earthworms. These earthworms produce humus in a composting process and purify the wastewater. The "trickling action" of the wastewater through the media also provides oxygen to the wastewater.

If it has typos, they are easy to correct. In which way does it "read terribly"? Remember sentences should be short so they are easy to understand for non-English native speakers. I tell you what I don't like about the paragraph that you prefer by putting my comments after each sentence:

A vermifilter (also called vermi-digester or many other names) is an aerobic treatment system comprising a passive biological reactor that removes organic matter, pathogens and oxygen demand from wastewater. 

-- what is a "passive biological reactor"? The wikilink goes to bioreactor which is actually something rather different. To say that the reactor removed organic matter and BOD is silly - BOD is simply a way of measuring the organic matter -- This is achieved via media that filters organic material from the wastewater and provides a habitat for composting earthworms that produce humus. -- when you say "media" I have simply clarified it with "certain media, such as wood chips" - isn't that clearer? -- The trickling action through the media also oxygenates the wastewater. -- the word "oxygenates" is unclear. Isn't it better to say "provides oxygen"?

The sentence "These earthworms produce humus in a composting process and purify the wastewater." that I had used is a simple copy & paste of what you had proposed here earlier in response to a comment by User:PlanetCare. I would actually like to hear from User:PlanetCare, too, as she would look at it from a layperson's perspective which would be helpful. - I will take another look now and remove bits that you might consider as "waffly". EMsmile (talk) 12:55, 15 April 2017 (UTC)

P.S. It's nice for you to be honest but isn't it a bit harsh to say "has been turned into a dogs breakfast. Its waffly, nondescript, has spelling errors and reads terribly."? I've really tried my best. :-( Let's also get the opinions from others, sometimes it helps to step away and get a new person to look at this. EMsmile (talk) 13:03, 15 April 2017 (UTC)

Changes made to the lead paragraph should really have been discussed individually above in "unclear sentences in the lead" before implementing.

Now that we have divided the changes into individual issues, lets look at these:

-- what is a "passive biological reactor"? The wikilink goes to bioreactor which is actually something rather different.--

Take another look at the bioreactor page, under types of bioreactors (2), 2.3 Sewage treatment.

Passive? Well, here is a link to a good paper describing the difference between active and passive wastewater treatment: http://www.soils.wisc.edu/sswmp/pubs/10.23.pdf

If Wikipedia does not yet define active and passive wastewater systems then I'm happy to put a page together!

--To say that the reactor removed organic matter and BOD is silly - BOD is simply a way of measuring the organic matter --

Try googling "removal of BOD". The following sentence correctly and concisely states that both bod and organic matter are removed: "that removes organic matter, pathogens and oxygen demand from wastewater." This is exactly what the vermifilter does. Sure, organic matter can be solids (including suspended solids), but oxygen demand is also generated by dissolved organics such as sugars. Please understand that BOD is not simply a way of measuring organic matter, but a way of measuring degradability of organic matter over a stated period of time (usually 5 days). Not all organic matter degrades in 5 days (most "solids" don't), therefore BOD is NOT a way of measuring organic matter at all...

Next, the lead paragraph now is several paragraphs mixed in as one:

A vermifilter (also called vermi-digester or many other names) is a technology for treating organic waste or wastewater using an aerobic environment and earthworms. In a vermifilter reactor, organic matter and pathogens are removed from the wastewater. The organic matter content of the wastewater is commonly measured by its biological oxygen demand - which is lower after it has been treated in the vermifilter. The reactor contains various types of filter media, such as wood chips, which filters organic material from the wastewater and provides a habitat for earthworms. These earthworms purify the wastewater and produce humus in a composting process. The "trickling action" of the wastewater over the filter media also provides oxygen to the wastewater. 

Note that a paragraph must contain one subject, the key is either the first sentence or last sentence. Lets look at one of those paragraphs contained in the lead paragraph:

"In a vermifilter reactor, organic matter and pathogens are removed from the wastewater. The organic matter content of the wastewater is commonly measured by its biological oxygen demand - which is lower after it has been treated in the vermifilter."

This is actually two additional paragraphs as currently worded. It is also nondescript and I would suggest misleading. Note that organic matter can be physically removed (filtration) and biologically removed (decomposition). For example dissolved organics are only removed biologically. Generally we think of decomposition of "compost" or solids rather than dissolved organics in water. You describe this as a "composting process" but I don't agree that production of humus within a substrate is actually "composting". Bacteria capture nutrients in the wastewater, are ingested by worms and digested into inert humus.

-- when you say "media" I have simply clarified it with "certain media, such as wood chips" - isn't that clearer? --

I don't believe so. The media can be virtually anything... plastic, textile, stones, gravel, bark, sawdust, soil, wood chips...the lead section does not need this level of detail. Furthermore "certain media" is waffly and nondescript.

-- the word "oxygenates" is unclear. Isn't it better to say "provides oxygen"?--

Currently: "The "trickling action" of the wastewater over the filter media also provides oxygen to the wastewater."

Previously: "The trickling action through the media also oxygenates the wastewater.".

It is not the trickling action over the media, but trickling THROUGH the media that "provides oxygen to the wastewater". Note that "providing oxygen to the wastewater" is meaningless, it is what happens to the oxygen, not the provision of it that matters! If you don't like "oxygenates the wastewater" then this could be changed to "to increase dissolved oxygen in the wastewater" or "dissolves oxygen into the wastewater".

Three lines of concise explanatory text have been turned into six lines that say less than the original three lines. As a starting point please take the lead section to this:

A vermifilter (also called vermi-digester or many other names) is an aerobic treatment system comprising a passive biological reactor that removes organic matter, pathogens and oxygen demand from wastewater. This is achieved via media that filters organic material from the wastewater. The media provides a substrate for aerobic bacteria and a habitat for composting earthworms that produce humus. The trickling action through the media dissolves oxygen into the wastewater, ensuring an aerobic environment for bacteria and worms to purify the wastewater.

..and then we can discuss and make improvements one at a time.SatchieNZ (talk) 23:56, 15 April 2017 (UTC)

Thanks for the additional explanations which makes it a lot clearer. I still don't agree with everything you said (I do agree with some parts). But anyway fine, feel free to take it back to the version that you liked better - just go ahead (don't wait for me). Some comments on your comments:

• I have been in wastewater treatment for a long time but the term "passive treatment" is not something that I find terribly important to explain to a layperson in the first sentence here. For me it is a waffly term. You probably mean for it to mean "lower energy using" treatment (similar to intensive vs. extensive treatment). Most of the time, a term like that is used to differentiate with the activated sludge process which is more energy intensive (e.g. some people would call a constructed wetland "passive"). There is by the way this article in WP on a related topic "Passive treatment system". Anyhow, this whole active vs. passive thing is not so important in my opinion. Isn't it just easier to speak about low energy usage as that's the main point, isn't it? In any case, a pump might still be required, depending on the setup. So if you said "low energy use" or "no external aeration" then you don't need to introduce the term passive which you would then have to explain.
• OK so let's make it: "increase dissolved oxygen in the wastewater" which is better than "oxygenate".
• Just because media can be all sorts of types doesn't mean it wouldn't help the reader's understanding to give one or several examples.
• Biological oxygen demand is commonly used to measure how clean a wastewater is, as per its Wikipedia article: "BOD is the amount of dissolved oxygen needed (i.e., demanded) by aerobic biological organisms to break down organic material present in a given water sample at certain temperature over a specific time period." So clearly, it is related to the organic material present, but in any case I don't know if a layperson really needs to know this in the first paragraph. So I don't think we necessarily need to mention BOD in the first paragraph of the lead.
• You said "Note that a paragraph must contain one subject, the key is either the first sentence or last sentence."? Why? I don't agree with that. The lead of the article should be about 4 paragraphs long, but a paragraph can contain several subject, as long as overall it summarises the article. I invite you to take another look at how leads are meant to be written here: WP:LEAD. It says "The lead is the first part of the article that most people will read. For many, it may be the only section that they read. A good lead section cultivates the reader's interest in reading more of the article, but not by teasing the reader or hinting at content that follows. The lead should be written in a clear, accessible style with a neutral point of view. The lead should stand on its own as a concise overview of the article's topic. It should identify the topic, establish context, explain why the topic is notable, and summarize the most important points, including any prominent controversies." - Have you ever shown this article (or only the lead) to someone not work-related (wife, mother, friend etc.) and asked them if they understand it? I am trying to look at it with a layperson's perpective. Yes, it has to be technically accurate. But it should also be easy to understand.
• About the composting, I was trying to implement what you had written some time ago above here where you had said "Perhaps the first paragraph could simply state "...that produce humus and purify the wastewater."". So producing humus sounds to me like a composting process - did I misunderstand?EMsmile (talk) 19:41, 16 April 2017 (UTC)

It's a real pity that only you and I are discussing this article. I wish more people would take an interest in making this really good, accurate and easy to understand! I will ask again on the Forum if anyone wants to help. EMsmile (talk) 19:39, 16 April 2017 (UTC)

Okay, so progressing the first paragraph of the lead based on this discussion, how about:

A vermifilter (also called vermi-digester or many other names) is an aerobic treatment system comprising a biological reactor containing media that filters organic material from wastewater. The media also provides a substrate for aerobic bacteria and a habitat for composting earthworms that produce humus. The trickling action through the media dissolves oxygen into the wastewater, ensuring an aerobic environment for bacteria and worms. Wastewater is purified by removing pathogens and oxygen demand.

SatchieNZ (talk) 21:07, 16 April 2017 (UTC)

OK, we're getting there, sound good. I've copied it across. Do we really need the term "composting earthworms" - what is the definition of that? (and I think we still need to make somehow the connection between organic matter and oxygen demand, so I've put it in brackets - perhaps still not ideal though. - I think from here on let's make edits directly in the article, but each time only few edits at a time with an explanation in the summary field. - We don't need to prediscuss every change on the talk page unless it's a "bigger" change.EMsmile (talk) 20:26, 17 April 2017 (UTC)

Explaining the issue of oxygen demand

The last sentence of the first paragraph was better left as

Wastewater is purified by removing pathogens and oxygen demand

than changed to

Wastewater is purified by removing pathogens and organic matter (oxygen demand)

This is because filtration of organic matter (removing it from the water into air) was already mentioned in the first sentence. The layperson thinks of organic matter as something solid. Purification of the water results from removal of oxygen demand. Lets use an example: It doesn't matter how much you filter urine, the oxygen demand will be high until decomposition takes place, because the organics such as urea are dissolved and highly degradeable. The dissolved oxygen is quickly used up so unless more oxygen is added the decomposition will become anaerobic (either way decomposition takes place on dissolved and highly degradeable organics first, then less degradeable organics). The process (decomposition) for removing oxygen demand is not the result (purification). "Purification" of wastewater is achieved by removal of oxygen demand (in this case via the process of aerobic decomposition + addition of oxygen). The demand on dissolved oxygen by micororganisms reduces over residence time because both oxygen is being dissolved and microorganisms are using oxygen and decomposing highly degradeable organics... bah... again simply defined as "removing oxygen demand"! By filtering out solid organics oxygen demand is reduced, provided those solids are exposed to an aerobic environment and therefore no longer demand oxygen from the water to decompose. This is different than traditional treatment where all decomposition takes place in the water. SatchieNZ (talk) 22:03, 17 April 2017 (UTC)

I don't really follow your reasoning, seems overly complicated and perhaps academic. How about "removing dissolved and solid organic matter as well as pathogens" (I would put pathogens second; see also next section below) The link to BOD can be made somewhere in the main text but do we really need it in the first paragraph of the lead? I am not sure. For me, as a wastewater person, BOD is something that we used to measure the strength of pollution. If you want to point out that organic matter can be soluble than let's say so - solid or dissolved organic matter would capture it, I think. EMsmile (talk) 22:18, 17 April 2017 (UTC)

Main thing for me is that it has to be accurate. We'd need to be careful about using the term "removing" organic matter. This means either physically removing (filtration) or decomposition. Reducing the "strength" of pollution = increasing the purification right? If oxygen demand were measured before and after a process, and it was reduced, some of the oxygen demand is removed. To remove oxygen demand, "removing dissolved and solid organic matter" through (bacterial) decomposition isn't enough in itself IF you want to retain an aerobic environment. Replacement of oxygen lost to oxidation from decomposition is the key. So removal of oxygen demand cannot mean just removal of organics, but also the simultaneous addition of oxygen (to remain aerobic). Thus removal of organic matter is a subset of removal of oxygen demand. Put another way removal of oxygen demand in water = loss of oxygen through decomposition of organic matter + addition of oxygen. You could say that

"Wastewater is purified by removing pathogens and organic matter via decomposition, which creates a flux of oxygen levels in the wastewater resulting from simultaneous oxidation of organics and replenishment of oxygen"....

but really all that needs to be said is "Wastewater is purified by removing pathogens and oxygen demand". SatchieNZ (talk) 02:41, 18 April 2017 (UTC)

Pathogen removal?

The lead mentions pathogen removal but this is not mentioned again anywhere in the article. Remember the lead is meant to be a summary. So if we know something about pathogen removal, it should be in the main article, too. Which pathogens is it removing? Helminth eggs OK but how much of the others? It is unlikely to be "full" pathogen removal but I assume a similar performance as constructed wetlands could be expected? Data and references?EMsmile (talk) 22:18, 17 April 2017 (UTC)

Its also in "Overview" section: "As a result of oxidation reactions, biodegradation and microbial stimulation by enzymatic action, organic matter decomposition and pathogen destruction occur in the vermifilter." There is a reference (faecal coliforms).SatchieNZ (talk) 02:47, 18 April 2017 (UTC)

Oh, strange, I missed it there when I searched with ctrl+F. But it's not a very good reference. It says submitted, has no year and no URL. Do we not have a better one? Also, this means nothing to a lay person: "It is possible to eliminate faecal coliforms to 2.0 Log10 of Most Probable Number (MPN) per 100 mL−1". Can it be simplified and wikilinks added? For example 99% removal. Also, do we need this overly scientific way of writing with the -1 in the superscript? Why not just mg/L (also in another place where that reference is used). If we talk about pathogen removal it would be good to have more information than just fecal coliform count. Let's not raise too high expectations, it's not a process for disinfection... (it doesn`t need to be either).EMsmile (talk) 12:21, 18 April 2017 (UTC)

Agreed. I didn't put that paragraph in there but can work on it when I have time. Happy with all of your suggestions and issues that need addressing. Aren't fecal coliforms used to as a representative measurement for pathogens in general? Then there are helminths which might be a "can of worms"... SatchieNZ (talk) 21:05, 18 April 2017 (UTC)

I have deleted that sentence in question for now. The way it was worded it was confusing. We should add a more accurate description of pathogen removal with the relevant references, as per our discussion on the Forum here. EMsmile (talk) 10:34, 15 May 2017 (UTC)

User:SatchieNZ - I just wanted to explain again why I had removed this sentence "It is possible to eliminate fecal coliforms to 2.0 Log₁₀ of Most Probable Number (MPN) per 100 mL⁻¹." Ask any layperson if they understand what 2.0 log10 means!? Anything wrong with just saying 99% removal? Also, as you pointed out on the Forum, the removal rates of fecal coliforms can be adjusted based on need, i.e. you change the design to get more or less removal. This is not reflected in this sentence which makes it sound like this is the maximum removal possible, but it is actually just quoting from one piece of research. I think we should rather have a more generalised statement and not have 2.0 log10. I also don't think we need to have "Most Probable Number (MPN) per 100 mL−1". The way it is worded in the example from Bear Valley is fine and correct, isn't it? EMsmile (talk) 23:19, 18 May 2017 (UTC)

I agree completely that the paragraph and terminology within could be simplified. This is being discussed in the Forum, so should we keep discussion to the forum? My point is that the whole paragraph refers to quantities from one research paper, so either remove them all or remove none. These removal efficiencies are a moving target, so in my view should not be quantified from results from one test in one research paper. It could just say "High removal efficiencies are possible for Chemical Oxygen demand, Total Suspended Solids (TSS), pathogens and NH4+" ...with more than one reference if requiring justification. SatchieNZ (talk) 02:09, 19 May 2017 (UTC)

That's a good idea. Do we have additional references we could use here? Meanwhile, I have changed the sentence a bit to make it clearer this is just from one example (I haven't check yet if it was lab scale, pilot or full scale).EMsmile (talk) 23:16, 22 May 2017 (UTC)

References

Typo on third diagram ? Says Fibber

https://en.wikipedia.org/wiki/Vermifilter#/media/File:Generic_domestic_vermifilter.jpg Not sure how to re-insert corrected diagram.

First, log in so we know who you are. Then, go into EDIT and click on the image. It will let you upload the corrected diagram. Best wishes Bio-CLC (talk) 23:42, 13 December 2020 (UTC)

yes, but how to make the edit inside of that diagram? I don't think it's possible without having access to the source file of the image? EMsmile (talk) 14:13, 5 January 2021 (UTC)