Re-Envisioning Sanitation As a Human-Derived Resource System

[NNadir]

The paper I'll discuss in this post is this one: Re-Envisioning Sanitation As a Human-Derived Resource System (John T. Trimmer,* Daniel C. Miller, Diana M. Byrne, Hannah A. C. Lohman, Noble Banadda, Katherine Baylis, Sherri M. Cook, Roland D. Cusick, Fulgensio Jjuuko, Andrew J. Margenot, Assata Zerai, and Jeremy S. Guest, Environ. Sci. Technol. 2020, 54, 10446?10459)

This is an interdisciplinary paper, the authors include Civil and Environmental Engineers, Agricultural & Crop scientists and economists, Natural Resource Scientists, Biosystems Engineers, a representative of a human development organization, and a sociologist. All but two of the authors are based at various institutions in the United States, two of the authors are based in Africa, one from Makerere University in Kampala, the other at the Community Integrated Development Initiative, also in Kampala.

It is also a policy paper, not a research paper - scientists suggesting policy in review of the associated science - which obviously has no meaning now, but in a better, saner world, would have meaning. Science and facts would matter.


(I wish the world were more like those 1950's Japanese monster movies where national emergencies, usually represented by the frat boy behavior of the members of the Godzilla Clan (Godzilla, Rodan, Mothra, Gamera...etc) with respect to power lines, would involve political figures calling on scientists, and doing whatever it was that scientists advised to deal with the monster emergency.)

The big monsters today are much worse than Godzilla and friends wading through the wires coming out of substations; they are air pollution, climate change, and Covid-19, listed in order of likely associated daily death tolls. The science of all three are easily swamped by public opinion, which is another monster which most of time can also be described as "ignorance unchained."

Right now, according to the World Health Organization, from which the orange racist national ignoramus, the "President" of the United States has caused us to abandon, about 2 billion people lack access to improved sanitation. I often discuss this state of affairs when remarking on the more than 3 trillion dollars that has been squandered on so called "renewable energy" since 2004, with the result that the rate of climate change is increasing not decreasing. We're not doing as well as those Japanese scientists recommending procedures to deal with Rodan.

About 300,000 people under the age of 5 die from diseases associated with inadequate sanitation, or about 820 a day. This is dwarfed by the number of people killed by air pollution every day (about 19,000 people per day) but still...but still...

Source: UNEP/Bloomberg Global Investment in Renewable Energy, 2019

Annual Mean Growth Rate for Carbon Dioxide Concentrations, Mauna Loa CO2 observatory, Hawaii

WHO fact sheet: Sanitation and Health

Decades ago, when I abandoned my parents politics and became a political liberal, liberalism included a huge concern for the impoverished, not just in the United States, but elsewhere. Today liberalism seems increasingly to include things like worshipping Elon Musk and his car for millionaires and billionaires and the conversion of the continental shelf and huge tracks of wilderness into industrial parks for wind turbines, but I think, there is still some interest in human development goals on the left, I think. I certainly hope so.

One thing that should concern environmentalists, agricultural scientists, human development workers, and in fact, everyone on Earth who cares about the future - not that many people do these days - is the disruption of, and likely collapse of, the phosphorous cycle.

Phosphorous is not a so called "renewable resource." All of the world's agricultural productivity is very much dependent on mined phosphate rock which is rapidly being depleted.

A subject addressed in this paper, among others, is phosphorous flows, since phosphorous is one of the valuable components of human fecal waste.

From the paper's introduction:

Globally, over two billion people lack basic sanitation access, and even more use systems that do not safely manage human excreta.(1,2) Progress toward the Sustainable Development Goal (SDG) of universal sanitation coverage by 2030 remains limited: of 123 countries with <95% basic sanitation coverage, only 14 are on track for universal coverage.(1) In resource-limited communities characterized by poverty, poor infrastructure, and constrained access to food, water, and other basic needs, high failure rates plague sanitation systems, leading to increased environmental and human health risks.(3,4) Simultaneously, global agriculture continues to consume finite nutrient resources (e.g., phosphate rock) while large quantities of phosphorus and anthropogenically fixed reactive nitrogen are discharged to pollute aquatic environments.(5,6)

Recovering human-derived resources from sanitation (e.g., water, nutrients, organic matter from bodily excreta) has the potential to offset treatment costs, substitute for expensive or nonlocal inputs (e.g., synthetic fertilizers, polyhydroxyalkanoates), and improve resource access for populations facing financial or productivity constraints.(7?9) Recent research and policy efforts, particularly those associated with sustainable and circular economies, have promoted shifts from pollutant removal to resource-oriented management.(9?12) However, although technology options are rapidly expanding, multiple socioeconomic, environmental, and engineering challenges coconstrain sanitation-based resource recovery efforts (e.g., economic viability of recovery, market potential, and consumer acceptance of products).(9,13?16) Recognizing these challenges, sanitation research is becoming more interdisciplinary and incorporating broader stakeholder involvement. Consequently, many studies have developed and applied models, tools, and approaches linking sanitation with social, environmental, and resource systems, with the goal of examining multiple dimensions of sustainability and supporting decision-making.(14?31) Work in Mexico City, for example, linked social acceptance (through participatory scenario development) with environmental outcomes (through resource flow analysis) to evaluate water and sanitation possibilities.(32) More generally, authors have used nutrient recovery to reframe sanitation as an overlooked component of food and farming systems.(10,33) Others have noted the importance of integrating economic, social, and engineering systems to ensure the effectiveness of natural wastewater treatment systems (e.g., constructed wetlands, lagoons), particularly concerning pathogen control and human health protection.(34) The phosphorus cycle has received particular attention,(35?39) and human-derived phosphorus recovery pathways were recently reviewed from an integrated social, ecological, and technical perspective.(40)...

...Sanitation represents an interface between society and nature. It is an integrated system that can be both beneficial, through human-derived resources recirculated toward positive use, and detrimental, when improper disposal degrades natural resources (Figure 1). Beyond sanitation, efforts to analyze coupled human and natural systems have been underway for over a decade.(46,49,50) Scholars have developed a generalized social-ecological systems (SES) framework,(41,44,51,52) which emerged from studying governance of common-pool resources (e.g., forests, irrigation systems, fish stocks)(53) and has been tested in many contexts.(42,54?60)...

This is a rather long paper, covering a broad range of practical and technical issues and I cannot discuss everything that is in it at this time, but it is an important paper of the type that I think is critical to sustainability and is, as public policy goes today, being almost completely ignored: Waste to resource, which is something that all life on Earth worked by until disrupted by anthropogenic practices, largely associated with industrialization. Restoration of sustainability, in my opinion, need not ban industrial practices, but it should to the maximum extent depend on closed waste to resource cycles. All I can do in the present case is to offer up some graphics and captions from the paper. Interested parties can seek out the full paper through academic institutions - when and if they are reopened for use by the general public - or by subscription.

Pictures from the paper:

The introductory cartoon:



Graphics from the text:



The caption:

Figure 1. Illustrative components of human-derived resource systems. Sanitation can function as an interface connecting multiple aspects of social, ecological, and resource systems. These linkages can be positive, as in cases where resources (water, organics, nutrients) are recovered and recirculated toward beneficial uses, or negative, as in cases where disposal displaces resources, contaminating environments and degrading ecosystem services.

The caption:

Figure 2. The sanitation social-ecological systems (S-SES) framework. (a) The diagram shows the seven first-tier variables (also called core subsystems; e.g., sanitation, actors, related ecosystems) of the S-SES framework and includes distinct categories (second-tier variables; e.g., technology selection, sanitation users, water) within each core subsystem. The framework structure extends beyond the first and second tiers to provide additional layers of detail as needed; structured lists of third- and fourth-tier variables can be found in SI Tables S1–S7. (b) Flows of human-derived resources through the core subsystems of the S-SES framework suggest how the safety and accessibility of resources may change as they move through various stages. Appropriate management, treatment, and recovery strategies, implemented by actors operating within a policy and regulatory environment defined by governance institutions, can increase safety and minimize risks associated with recovered resources. However, these processes may introduce constraints on access related to technology availability, economic resources, and knowledge of sanitation and hygiene.

The supplemental information should be available for free at the link to the parent paper at another link therein.



The caption:

Figure 3. An illustration of the framework’s multitiered structure, using the sanitation subsystem as an example. The sanitation subsystem is expanded into four second-tier variables. Of these, we further expand technology and system selection (SAN.T) and outcomes (SAN.O) to show nested third-tier variables (the other two second-tier variables also contain lower tiers not pictured here). Two third-tier variables are then expanded to the fourth tier. For all core subsystems, full structured lists showing four tiers of variables can be found in SI Tables S1–S7. Additional variables, in levels beyond the fourth tier, can offer even greater levels of system detail and contextual depth. As they are likely to become increasingly context-dependent, we have not specified variables beyond the fourth tier. On the left, we show how a tiered structure is important when developing a shared vision and lexicon. Many studies may benefit from high levels of generality or precision, but finding a balance is important for effective interdisciplinary communication. Otherwise, researchers may remain trapped within existing boundaries by keeping other topic areas too vague or being too dependent on implicit disciplinary assumptions. A multitiered conceptual framing can help researchers speak to others with different perspectives, balancing these two extremes at midlevel tiers. Researchers can delve deeper to identify key aspects of ancillary topics, or translate specialized results to identify generalizable knowledge, typologies, and guiding principles.

The caption:

Figure 4. The changing nature of human-derived resources. This figure illustrates how a conceptual framework can provide an integrated lens across disciplines and concepts, suggesting new ways of understanding sanitation that can then be studied further. Here, we show a synthesis that arose organically as we developed the framework and allowed it to influence our own thinking. Integrating ideas from fields including economics, natural resources, and health, we considered how different types of reuse pathways change the nature of human-derived resources. Specifically, we consider the types of goods these resources represent, as defined by their excludability (i.e., the degree to which actors can be barred from using the resource) and rivalry (also called subtractability; i.e., the degree to which resource use diminishes the quantity or quality of the remaining supply). Sanitation systems manage and treat bodily excreta to reduce risks associated with reuse or disposal, but limited access to technologies, economic resources, and knowledge regarding appropriate strategies can function to exclude vulnerable populations. Advanced recovery processes that generate more expensive, higher-value products (private goods) may further increase excludability. Alternatively, other pathways (for example, those connected with ecosystem services) may generate common-pool resources (e.g., provisioning of forests or fish stocks) or public goods (e.g., regulation of water or air quality). In the interest of completeness, the figure includes club goods—the fourth general category of goods, defined by high excludability but low rivalry—although this category does not enter directly into our discussion of human-derived resources.

I trust you are enjoying Labor Day safely.

[Laelth]

1. That's a serious contribution. Thank you.

How fortunate (for us all) that you abandoned your parents’ politics way back when and became a political liberal.

I am still chewing on the meat of this policy proposal, but I am all for the idea that we should maximize the value of human waste.



-Laelth

[ihas2stinkyfeet]

2. cook county water rec

mixes their solids w woodchips, and sells by the truckload to farmers. has for a long time.
but last year they started selling bagged solids as fertilizer.

it it the one thing i have to add to my garden, as composted organic matter doesnt have it. next time i need it, i intend to get it from them.

plus, i do usually wear a dress in the garden. a little pee in the right place makes the tomatoes happy.
if only i could get the pendejos who drink beer in the alley and pee behind the trash cans to pee in my composter.

eta- this makes me want to install a composting toilet on my alley. fair number of homeless around here. it would be a service. wouldnt bother me to hose it out when needed.
assuming they are frowned on in houses. but...

[Warpy]

3. Until very recently in the west, there's been a lot of money in muck

Gong farmer was a well paid if not well respected occupation from the Middle Ages forward in England. Cess pits were often just what we now sweetly call the basement in town houses and the gong farmer was called to dig it out when it got full. Early gong farmers either sold their wagon loads at rural lands outside the city or composted it themselves, mixing it with chaff, straw, and other organic waste.

By the beginning of the eighteenth century, there was another important use for it in the manufacture of gunpowder.

Urine had always provided the basic household chemical, urea converted into ammonia which is a potent degreaser for linens and surfaces. It had been so important in the ancient world that Rome had put a tax on it.

It's only since the invention of sanitary systems that it has fallen out of favor as either a fertilizer (which reamains the case in much of the world) or a precursor to the manufacture of gun powder.

It has certainly been an overlooked resource, especially in big cities where getting rid of it is an increasingly urgent problem. In underdeveloped rural towns, there are already pilot programs harvesting the methane generated during decomposition for cooking fires. Translating those pilot programs into wide usage has always been the problem.

[hunter]

4. We have a very sophisticated sewage treatment plant serving our city.

It can turn sewage into potable water that's currently used for irrigation and groundwater recharge.

Unfortunately the sludge is too contaminated with industrial waste, pharmaceuticals, etc., to use directly as fertilizer. Alas, the sludge is dried and used as landfill cover so the nutrients it contains are wasted.

In Mexico City these contaminants in treated sewage are generally ignored and the water and sludge are used for agriculture. These contaminants end up in the soil, ditch water, and to a lesser extent agricultural produce.

Science and engineering could solve these problems. All it takes is a commitment to protect our environment and recycle our waste.

Every human deserves toilets that don't spread disease, don't pollute the environment, are not difficult to maintain, and recycle water and nutrients.

My parents and my wife's parents live in rural areas and their toilets are connected to septic systems. They drink surface water, rain or snow melt, and their wastewater goes into the ground. Most of this lower quality water is pumped up for agricultural uses, but a certain amount of it ends up in domestic water supplies and surface water, some of it in the domestic water of people who are not as well off as they are.

This is a recognized problem where my wife's parents live and new conventional septic tank installations have been prohibited. Expensive micro sewage treatment plants are required instead. These are powered by electricity and produce consumable waste (filters, etc...) that end up in landfills. If they are not maintained they are no better than septic tanks.

Composting toilets are frequently mentioned as an alternative to septic systems but these are not flush-and-forget and require a certain commitment to safety and maintenance. Affluent people who enjoy flush-and-forget toilets themselves really shouldn't be promoting alternative sanitation systems to those not as fortunate as themselves.

Human communities need sophisticated sewage treatment systems. That's just the way it is. My great grandma lived with an outhouse on the family ranch, but that's not a safe sanitary system when there are near eight billion humans mostly living in cities, suburbs, and villages.

[NNadir]

5. When your most explored and favorite tool is a hammer, you try to make every problem as a nail.

I'm no exception, to be sure.

Hydrogen production and phosphorus recovery via supercritical water gasification of sewage sludge in a batch reactor (Weijin et al., Waste Management Volume 96, 1 August 2019, Pages 198-205)

Supercritical water gasification of sewage sludge: Gas production and phosphorus recovery (lNancy Y.Acelas Diana P.López, D.W.F. (Wim)Brilman, Sascha R.A.Kersten, A. Maarten J.Kootstra, Bioresource Technology Volume 174, December 2014, Pages 167-175)

I've actually given a lot of thought - surprising considering my limited view on things - to utilizing this approach for sewage sludge - which happily contains quite a bit of water, using oxyfuel combustion as opposed to nuclear heat, although nuclear heat would also work.

I saw this as an application, admittedly, for the oxygen generated from the nuclear heat driven thermochemical splitting of carbon dioxide or water.

Sewage sludge is currently utilized in many places as fertilizer, but as you correctly point out, urban sewage contains a lot more than phosphorous and salts, personal care products, metals, notably lead from waste lines and old solder, other heavy metals, excess copper, and pharmaceuticals and their metabolites. The role that sewage plays in the generation of antibiotic resistant bacteria is a very active area of investigation.